CHAPTER II
Evaluation of the Vascular Status in Traumatic and Nontraumatic Lesions of the Blood Vessels
Ambrose H. Storck, M.D.*
The evaluation of the vascular status of patients with traumatic and nontraumatic lesions of the blood vessels encountered in World War II went considerably beyond mere diagnosis and differential diagnosis. It was useful, or essential, or both: (1) to determine the exact location and extent of a lesion or injury and to follow the progress of the disorder; (2) to determine vascular tone, patency of arteries and veins, functional capacity of blood supply, and adequacy of collateral circulation; (3) to establish need for surgical intervention, to select correct operative procedure and optimum time for operation and to assess the results of surgical therapy; (4) to establish therapeutic procedures other than surgical and to assess their results; (5) to determine the disposition of the patient whether for return to duty or for discharge, and, in the event of the latter, to establish degree of disability for pension purposes and to advise the patient regarding the resumption of his civilian occupation.
In medical installations in zones of combat and of communication the excessive workload of the medical personnel and the lack of special equipment made it mandatory to depend upon clinical methods alone for the study of casualties with injuries to the blood vessels. Clinical methods also constituted the major part of the investigation of the vascular status of casualties admitted to the three vascular centers in the Zone of Interior. The main reason for this reliance on clinical methods was that they yielded far more useful information than other types of investigation. There were, however, other reasons. In the beginning when the centers were first established, procurement of special facilities and diagnostic equipment was very slow, and the patient loads were heavy. In addition there were serious shortages in various categories of individuals, professional and technical, able to operate the special equipment as it became available. In fact it became necessary to institute a training program to overcome the lack of experience in management of vascular lesions and to develop teamwork among the ever-changing personnel.
The outstanding results achieved at all the vascular centers in spite of the initial shortages in equipment, supplies, and personnel, as well as of certain shortages which persisted to the end of the war, demonstrated two things clearly: (1) it is possible to provide safe and satisfactory care for patients with vascular lesions with limited facilities and equipment for special diagnosis; (2) given a nucleus of experienced personnel, it is possible to train personnel
* Professor of Clinical Surgery, Tulane University School of Medicine. Colonel, MC, USAR.
18
and to develop teamwork to meet all the essential requirements of avascular center.
It should be mentioned, however, that the value of and need for certain special facilities-controlled temperature and humidity rooms and a minimum of certain other equipment--were never questioned. Each center was provided with a soundproof, specially insulated room built with 3 inches of cork block and with accoustically treated celotex on the ceiling, floor, and walls (Fig.1). Apparatus with automatic thermostatic controls made it possible to regulate the temperature within these rooms at levels ranging from 40o to 110o Fahrenheit. Changes between the possible extremes of temperature could be effected within 45 minutes and changes of 10o or less, within 15 minutes. The air, which was filtered, was kept at a low humidity, usually 40 to 45 percent. Details of the provision of essential special diagnostic equipment have been given in Chapter I.
Consideration of the various objectives of the vascular evaluation and of their implications will make it clear why in most cases serial studies were carried out before and after operation and why in many cases testing was an essential part of the operative procedure. There were other reasons for the use of such studies including the possibility of error in the first test or tests; transient
19
psychic, environmental, and other influences which might affect the results; and possible improvement in, or worsening of, the patient's condition over a period of days, weeks, or months. As a rule, the diagnosis had been established before operation was undertaken, but in an occasional instance it proved impractical or impossible to localize the lesion accurately or to arrive at a diagnosis by indirect methods. In such cases surgical exploration was necessary for diagnostic as well as therapeutic purposes.
In this chapter the various clinical and laboratory techniques employed in the evaluation of the vascular status of patients admitted to the vascular centers at Ashford, Mayo, and DeWitt General Hospitals during World War II will be described. The techniques were for the most part the same at all three centers; any variations will be specified.1 An occasional method will be described in greater detail in other chapters in this volume; however the indications for the various tests, the techniques, and the interpretation of results will be discussed completely, though in some instances briefly, in this chapter.
Clinical Material. The types of disorders encountered in the vascular centers were, with the exception of cold injuries, the same as those commonly encountered in the peacetime civilian population, but with a different distribution.
With comparatively few exceptions all patients were in the age group between 18 and 45. The younger patients far exceeded the older. An overwhelming majority were males, but as the war progressed, members of the Army Nurse Corps and of the Women's Army Corps were seen in increasing numbers with various noncombat-incurred vascular disorders.
The racial distribution of patients with vascular lesions was as varied as the racial makeup of the Army; however there were certain disproportions. Comparatively few Negroes were seen at any of the centers and at Ashford General Hospital, where a special study was made, a disproportionately large number of Caucasians with thromboangiitis obliterans were noted to be of the Jewish faith. Percentagewise these latter patients accounted for 35.8 percent of those with the disease.
Trenchfoot, immersion foot, and frostbite, especially high altitude frostbite, presented problems new to most medical officers. As a result, rapid formulation of diagnostic methods was necessary. Numerically, immersion foot and frostbite were not important, but trenchfoot by reason of the overwhelming number of cases was extremely important. On the other hand arteriosclerotic vascular disease, frequently observed in civilian practice, furnished few problems because of the youth of most of the military personnel.
Recording Methods. Standard data concerning vascular casualties (history, physical findings, and laboratory reports) were entered on the sheets regularly in use in Army hospitals. In most cases special and repeated tests proved necessary and the data thus secured were entered on special forms which had
1 Standardizedtechniqueswhich were employedwithout modification will not be described indetail.
20
been devised at the three vascular centers. These forms were by no means ideal but the heavy workload and the number of relatively or completely inexperienced persons who were recording the observations made shortcuts of this sort necessary. The use of these forms assured the uniform recording of pertinent data and also simplified the tasks of review and analysis of the records when lessening of the workload permitted these investigations. The special forms devised for patients with trenchfoot and other cold injuries proved invaluable when the centers were suddenly called upon to test and treat large numbers of casualties with these conditions.2
In cases exhibiting vascular lesions of particular interest, photographs, including color photographs, were employed to supplement the initial records as well as to show the intermediate status of the patient and the final results of treatment. Infrared photography was used to demonstrate collateral venous channels not visible by inspection. Photographs were taken at the operating table and specimens photographed according to the indications in special cases. These photographs were often supplemented or replaced by illustrations drawn by artists.
Both photographs and drawings were regarded as essential parts of the record. They were provided as often as circumstances permitted because physical appearances could thus be correlated with the results of various tests.
CLINICALHISTORY
GeneralInformation
The special vascular history secured data which covered the patient's chief complaint, given in his own words; family history including any occurrence of vascular disease in his forebears; previous history including any occurrence of venereal disease, previous operations or injuries, possible exposure to excessive cold, incidents of phlebitis or migratory thrombophlebitis, and any isolated symptoms or manifestations of preexisting vascular disease; also his military history including assignments in the Zone of Interior and overseas with details of duties and experiences.
In addition, every patient with a vascular injury or nontraumatic vascular disorder was carefully questioned in order to secure a chronologic, factual, circumstantial account of its occurrence or development and to elicit symptoms and happenings which might have a possible relation to the vascular system. The taking of this history afforded an excellent opportunity to gain some insight into the patient's general attitude and characteristics. His own estimation of the disease or injury was frequently revealing, especially in regard to his evaluation of the related degrees of disability and functional limitation.
The patient was questioned concerning the use of tobacco in the form of cigarettes, cigars, pipe, chewing tobacco, and snuff, the amount used, and the
2 Vascular Surgery--Forms. HD: 730.
21
duration of the habit. He was similarly questioned concerning the use of alcohol and drugs. His dietary habits were inquired into with special emphasis on those which might result in vitamin deficiency or general nutritional deficiency.
SpecificInformation
As far as was practical, data concerning the patient's present illness or injury were obtained in his own words, supplemented by such questioning as might be necessary in order to obtain the essential information concerning:
1. The time and place of injury or the place and date of the onset of symptoms.
2. The conditions or circumstances under which the injury was sustained or the symptoms first experienced. If the lesion was traumatic, a special note was made about the amount of the blood loss and whether or not infection had followed.
3. The methods and circumstances of evacuation were elicited including times and places, the manifestations en route, the findings so far as the patient knew them, previous treatment, and results obtained during previous hospitalizations for the present condition.
4. All symptoms experienced. Detailed questions were asked about those symptoms which might reflect abnormal vascular tone, vascular occlusion, or impaired vascular functional capacity. Details were also secured upon the location, onset, duration, and severity of special symptoms and signs, as well as on environmental conditions, activities, or other circumstances which relieved or aggravated them.
5. Specific data concerning the character, intensity, and chronicity of pain, as well as the circumstances under which it occurred, was aggravated, or relieved. The occurrence of rest pain or pain following exercise was noted. A distinction was made between pain in the small muscles of the foot and pain in the calf muscles; the experience at the vascular center of Mayo General Hospital showed that this distinction was important in thromboangiitis. Other symptoms and signs about which the patient was questioned if he did not himself supply the information included coldness or abnormal warmth of the hands and feet and other areas of the skin, excessive dryness of the skin or excessive sweating, abnormal fatigability, numbness, tingling, burning, anesthesia, hypesthesia, hyperesthesia, alternating warmth and coldness, cold or heat sensitivity as distinguished from coldness or abnormal warmth, pallor, rubor, cyanosis, edema, stiffness, vesicle-formation, desquamation, ulceration, gangrene, loss of nails, varicosities, and symptomatic evidence of associated nerve injuries.
6. Injuries or lesions occurring in parts of the body other than the extremities. Here a different line of questioning was adopted. If an intracranial vascular lesion was suspected, such as an intracranial aneurysm or a carotid-cavernous sinus arteriovenous fistula, inquiries were made concerning
22
such symptoms as headache, vertigo, tinnitus, syncope, periods of unconsciousness, convulsions, motor or sensory abnormalities, nausea, and vomiting. If an intrathoracic vascular lesion was suspected, the questioning was directed to such symptoms as cough, expectoration, chest pain, voice changes, dysphagia, and dyspnea. Myocardial changes, cardiac decompensation, and other cardiac alterations were regarded as possible associated states in special types of injuries and lesions and the questioning in these cases was directed to the occurrence of palpitation, dyspnea, orthopnea, cough, and other symptoms and signs indicative of cardiac involvement.
Emotional Status. Emotional and psychologic factors played a more important role in the military casualty than in the civilian patient. They had to be taken into consideration in obtaining the clinical history and interpreting certain subjective reactions to physical examination such as pain, tenderness, and claudication. Phlegmatic individuals, just as in civilian life, tended to minimize their symptoms, while excitable or poorly adjusted patients tended to exaggerate theirs. Intentional or unintentional distortion or inaccurate description of symptoms was not uncommon.
Emotional factors connected with life in the Army were especially likely to assume importance in the vasospastic group of patients. The most important of these factors were regimentation, separation from family, fear, including fear of return to duty, which was especially prominent in enlisted men as compared with officers, and the desire to be compensated for injuries. Judicious questioning was necessary to elicit and evaluate these various factors. It was also necessary to observe the patient and to consider him from the standpoint of general appearance, attitude, off-guard behavior, and habits. These indirect observations were often of great importance in the evaluation of the emotional and psychologic components of the vascular status. In some instances neuropsychiatric consultation was necessary for complete evaluation and disposition.
Repetition of Questioning. The more or less sudden changes which often occurred in patients with vascular lesions as a result of physical and other environmental influences or of emotional reactions, or as the result of rapid regression or progression of the vascular lesion, made it necessary to question the patient frequently concerning the status of his symptoms, the possible appearance of new symptoms, and his own evaluation of his condition. Repeated questioning was as necessary as repetition of objective studies. It was observed, for example, that patients with trenchfoot who had complained of great pain, had actually manifested excessive sweating and color changes in the affected part, and had gladly accepted litter transportation, often, shortly after their arrival in the Zone of Interior, experienced rapid reduction of pain and showed great improvement in other subjective manifestations. Improvement was always notable when these patients learned that it was not Army policy to return patients with trenchfoot to duty. Failure to appreciate the likelihood of these rapid changes and to look for them in patients with trench-
23
foot and other vascular lesions could conceivably have resulted in unnecessarily radical, actually harmful, therapeutic measures.
PHYSICALEXAMINATION
GeneralConsiderations
Ordinary methods of physical examination were combined with special methods which required no complicated apparatus or equipment. In the course of routine physical examination search was made for indications of injury to, or occlusion of, blood vessels, abnormal arteriovenous communications, abnormal vascular tone, impaired functional capacity, and trophic or other changes. Special tests were then carried out according to the indications of the particular case. Inspection, palpation, percussion, auscultation, and mensuration were found to be essential phases of all such examinations. The vascular findings were described in as much detail as time permitted and were also indicated on special diagrams.
The initial physical examination was usually performed in ordinary environmental circumstances, in the ward, the patient's room, or the standard examining room. Subsequent examinations were conducted in a room in which the temperature and humidity could be controlled. The temperature was usually kept at 68o to 78o F. and the humidity at 40 percent. All examinations were carried out with the patients entirely, or almost entirely, disrobed.
The possible effects of environmental temperature and humidity at the initial (routine) physical examination, and of psychic and emotional influences at all examinations, had to be taken into consideration in the interpretation and evaluation of all findings. Another reason for repetition of physical examinations was the possibility of rapid regression or progression of physical manifestations of vascular lesions. This was particularly true in such types of lesions as pulsating hematomas and aneurysms which sometimes increased rapidly in size and consequently produced nerve damage and circulatory impairment distal to the site of the lesion.
Height and weight were recorded at the original examination, and weight was determined as often as seemed indicated thereafter provided the patient was not weighed at regular (usually weekly) intervals.
Vital Signs
In the absence of infection the oral temperature supplied no special information in patients with vascular injuries and lesions, but its observation formed part of every physical examination. Pulse rate was determined in an artery presumed free of injury or disease. Respiratory rate was recorded routinely but seldom furnished information of much significance.
Blood pressure was also taken in some artery not directly involved in the vascular injury or lesion and regarded as least affected by it. Determination
24
of comparative pressures proved a useful method of examination in vasospastic and obliterative vascular lesions, as well as in arteriovenous fistulas, arterial aneurysms, and arterial occlusions which had been produced surgically. When the extremities were fat or edematous determination of blood pressure was often unsatisfactory and unreliable. Better results were secured in such cases when a special wide cuff was substituted for the usual sphygmomanometer cuff. Serial determinations of the blood pressure were important as findings might alter from time to time, sometimes from day to day. It was noted that after the closure of large arteriovenous fistulas the blood pressure was sometimes considerably elevated, even to hypertensive levels. Blood pressure determinations after temporary obliteration of the blood flow through an arteriovenous fistula will be discussed later in this chapter.
Inspection
General inspection of the entire body was followed by detailed inspection of special parts, particularly the extremities. Comparative observations were always made on both extremities.
Inspection was directed to the following points:
1. General development and nutritional status of the body.
2. The facies, particularly for the presence of exophthalmos.
3. The poise, attitude, manner of speech, and general behavior.
4. The gait, whether normal, limping, asymmetrical, or of the heel type, and whether there was weight-bearing on the lateral edges of the feet.
5. The respirations, whether normal, dyspneic, or orthopneic.
6. The general coloring, with special reference to pallor, cyanosis, or mottling.
7. The distribution of hair on the toes, feet, legs, fingers, hands, and forearms.
8. The muscular status, with special reference to atrophy or hypertrophy.
9. The skin, with special reference to vesiculation; pigmentation of abnormal degree or distribution; trophic changes, including thickening (hypertrophy) or thinning (atrophy); callus-formation; fibrosis; scleroderma; desquamation, with special reference to the degree and distribution.
10. The presence of amputations or contractures of the digits or of portions of the extremities.
11. The presence of healed or unhealed wounds, and of scars.
12. The presence of ulceration of the digits or of other areas.
13. The presence of infection and its differentiation into pyogenic and mycotic types.
14. The presence of gangrene (moist, infected, or dry) and of lines of demarcation and separation.
15. The condition of the nails and finger tips, with special reference to ridge-formation, rolling, cracking, cornification, and clubbing.
25
16. The presence of masses and their differentiation into pulsating and nonpulsating types.
17. The presence of other abnormal pulsations.
18. The status of the blood vessels with special reference to visibly tortuous arteries, collateral venous channels, and varicosities.
19. Abnormal sweating or abnormal dryness of the skin, its degree, distribution, symmetry or asymmetry, and constancy or intermittency. Special sweating tests were carried out as indicated.
20. Edema, with special reference to location, degree, extent, and character (whether pitting or nonpitting).
21. Color changes in the affected extremity.
Careful observation of changes of color in the extremities was of great importance in vasospastic and obliterative arterial diseases and was occasionally of value in the estimation of circulatory impairment in patients in whom there had been loss of continuity of blood flow in the main arterial stems as the result of trauma or operation. The examination called for no refined methods of judging color but merely for careful observation of the involved extremity and comparison with the opposite extremity. Good daylight was essential and the preferable environmental temperature 76o Fahrenheit. Observations were made with the patient recumbent and with the limb to be investigated placed successively in the horizontal, dependent, and elevated positions. Note was made of the extent and degree of cyanosis, rubor, pallor, and livedo reticularis, and of the changes of color occasioned by return of the extremity to the horizontal position after either elevation or dependency.
In addition to the observations already listed, two possible clinical entities were looked for: (a) phlebitis, with special reference to the location, extent, degree of clotting, and activity or inactivity of the involved veins, and (b) migratory phlebitis, with special reference to the distribution and character of the lesion, the presence of local pigmentation and fibrosis, and the appearance of areas of fresh venous inflammation.
Palpation
Palpation was an indispensable method of examination in patients with penetrating wounds. It was done with great care in the vicinity of the wounds of entry and exit and in the area between them in order to detect possible thrills and pulsations. When a penetrating wound had been produced by a bullet, shell fragment, or other foreign body which had not made its exit, the area between the wound of entry and the site of roentgenologic visualization of the retained foreign body was carefully palpated. When there were multiple and widely distributed penetrating wounds, it was the usual practice to palpate the entire body. Areas contiguous to fractures were also palpated with special care.
Certain data secured by palpation were in confirmation of, or in extension of, data already obtained by inspection; these particularly concerned edema,
26
abnormal dryness or excessive sweating,trophic changes in the skin, and the presence of massesand abnormal pulsations. Other data obtained by palpation included:
1. Surface temperature, with particular reference to grossly detectable deviations from the normal, including coolness or coldness, localized hot spots, and diffusely increased heat.
2. Variations in sensation, including anesthesia, hypesthesia, hyperesthesia, and tenderness. Tenderness in the ball of the foot was always looked for in patients with trenchfoot, and tenderness in the calf was always investigated in patients with suspected venous thrombosis.
3. Fixation of the skin as the result of recent or old traumatic or inflammatory processes.
4. The status of the musculature, with special reference to spasm and atrophy. When the scalenus anticus syndrome was known or suspected to be present, tenderness or spasm of the shoulder girdle was investigated.
5. Thrills, which indicated the presence of arteriovenous fistulas and arterial aneurysms.
6. Venous thrombosis, which might be present in phlebitis involving the superficial veins.
7. Varicosities not demonstrable on inspection, particularly in obese patients or in patients with edema and cutaneous and subcutaneous fibrosis.
8. Atheromatous changes in the peripheral arteries.
9. Anatomic vascular anomalies, including absence and/or displacement of arteries from their normal location as the result of aberrant development. In a fairly large number of apparently normal persons dorsalis pedis pulse could not be palpated at all, while in others it was found in anomalous locations.
In addition to generalized palpation of the whole body or of certain regions, main arteries of both the upper and lower extremities (dorsalis pedis, posterior tibial, popliteal, femoral, radial, brachial, and axillary) were palpated to determine the degree of elasticity, the presence of arteriosclerosis, tortuosity, thrills, and the volume or amplitude of pulsation. Special attention was directed, when indicated, to other arteries such as the temporal artery.
If the radial pulse was palpated with the arm in hyperabduction, it was borne in mind that compression of the subclavian artery may occur in some normal persons when the arm is in this position, with resulting diminution or obliteration of the radial pulse. It was also borne in mind that palpation of the radial pulse during forced respiration against resistance may likewise reduce or obliterate it and that a radial pulse may be absent as the result of a developmental anomaly.
The degree of pulsation was recorded either as good, moderate, faint, or absent, or on a scale of 0 to 4, 0 indicating absent and 4 normal. Care was taken to indicate whether the record concerned the pulse on the right or the left side; both were always tested.
27
Percussion
Percussion was employed routinely to define the borders of the heart, particularly for the demonstration of cardiac enlargement in patients with arteriovenous fistulas. It was probably the least useful of the various methods of physical examination employed in patients with vascular injury or disease.
Auscultation
Auscultation was carried out, as under ordinary circumstances, to detect cardiac murmurs and variations in the cardiac rate and rhythm. These data were of special importance in patients with arteriovenous fistulas. This method was also useful in searching for bruits in areas in which thrills had been palpated. It was done routinely:
1. In patients with multiple penetrating wounds. In such cases it was carried out, like palpation, over the entire body, especially along the course of major arteries in search for vascular lesions manifested by the presence of a bruit.
2. In the vicinity of wounds of entry and exit and in the area between them, or in the area between a wound of entry and the site of roentgenologic visualization of a retained foreign body.
3. In regions contiguous to fractures, in search for bruits which would indicate associated vascular lesions.
The ordinary stethoscope was used at all the vascular centers. At the DeWitt General Hospital there was used, in addition, the double stethoscope known as the symballophone. This instrument permitted auscultation at two separated points simultaneously.
Mensuration
Mensuration which demonstrated possible differences in the circumference of the extremities at various levels was particularly useful in patients with thrombophlebitis, arteriovenous fistulas, or arterial aneurysms. Comparative measurements were always made on the contralateral limb and the method was always used serially.
The practice differed somewhat at the three centers. At Ashford General Hospital five measurements in the lower extremity were taken, at the midpoint of the foot, the ankle, 18 cm. below the midpatella, at the level of the knee, and 18 cm. above the midpatella. In the upper extremity five measurements were also taken, at the midpalm, the wrist, 10 cm. below the olecranon process, at the cubital level, and 10 cm. above the olecranon process. These points were marked on the extremities before mensuration was begun.
At the Mayo General Hospital Vascular Center the procedure was as follows: The thigh was measured at a point 5 to 6 inches above the upper border of the patella; the leg 4 to 5 inches from the lower border of the patella; and the lower leg 1.5 inches from the upper border of the internal malleolus. All measurements were made first with the knee flexed and then with the extremity lifted from the bed. The lower edge of the tape measure was placed slightly
28
above the guide mark and the extremityencircled at exactly the same level all the way around.
Tests forNerve and Muscle Status
The frequent association of other injuries with vascular injuries required examination of the affected parts for bone, nerve, and muscle injuries which had practically always been detected before the patients reached the vascular centers but the sequelae of which were not always clear. Demonstration of the sequelae of nerve injuries required testing for normal and abnormal reflexes, areas of hypesthesia, hyperesthesia, and anesthesia, tenderness in the balls of the feet, and atrophy of the muscles of the feet and hands. Observations based upon active and passive movements and upon manipulation of the extremities or, in some instances, of the neck, furnished information about the limitation of motion caused by muscle weakness resulting from nerve injury, circulatory impairment, disuse, stiffness or ankylosis of joints, and pain resulting from movement but attributable to other causes.
The functional limitations manifested by the presence of claudication will be discussed later in this chapter.
Ophthalmoscopy
The use of the ophthalmoscope was a routine part of the general examination in patients in the upper age groups and in patients of all age groups with intracranial aneurysms or with arteriovenous communications between the internal carotid artery and the cavernous sinus. Examination of the retinal vessels by this means often yielded information of considerable value.
CLINICALLABORATORY TESTS
The majority of clinical laboratory tests were found to be of little or no help in evaluating the status of patients with either organic or vasospastic obliterative vascular diseases. This statement holds for the blood coagulation time, the bleeding time, the sedimentation rate, and hematocrit determinations. Prothrombin time determinations, while they were of no help in evaluation of the vascular status, were essential in patients receiving dicumarol (bishydroxycoumarin) therapy. Coagulation time determinations did not reflect the anticoagulant effects of dicumarol as they did in patients receiving heparin.
Blood chemistry determinations seldom furnished significant data in the patients seen at the vascular centers. This might have been expected as most of them were young and healthy adults in whom abnormalities of the blood chemistry were unlikely to be present.
The heparin tolerance test suggested by De Takats 3 was used in a limited number of cases at the vascular center of DeWitt General Hospital but did not yield uniformly dependable results and was considered of little clinical value.
3 De Takats, G.: Heparin tolerance; test of clotting mechanism. Surg., Gynec. & Obst. 77: 31-39, Jul 1943.
29
SPECIAL TESTS WITHOUT INSTRUMENTS
To supplement the data obtained by ordinary methods of physical examination, certain maneuvers and tests which did not require special diagnostic equipment were employed. One such group of tests consisted of Allen's blanching test, Samuels' plantar test, the exercise test for the upper extremities, the ischemic pain test, and Homans' dorsiflexion test.
Blanching Test (Allen)
Allen's test, which was used when one of the main pulses in the wrist was not easily palpable, was performed by elevating the patient's hand above the level of the head until blanching appeared. The radial artery was then compressed and the hand brought down. Persistency of blanching in the dependent position was taken to mean occlusion of the ulnar artery, while prompt return of color was taken to mean that the ulnar artery was patent. The test was sometimes repeated after a 1-percent procaine solution had been injected into the stellate ganglion in order to eliminate a possible vasospastic element.
Plantar Test (Samuels)
Samuels' plantar test, which is an exercise test for the lower extremities, was performed with the patient recumbent and the lower extremities elevated at an angle of 45 degrees or more. The color of the soles was noted before and after the limbs had been raised. The patient flexed and extended the feet with the ankle as a pivot for 2 to 3 minutes. If the arterial supply to the feet was adequate, the plantar surfaces kept their normal pinkish tinge. In the presence of arterial occlusion of even minimal degree a decided pallor became apparent usually within 2 to 3 minutes, though it did not necessarily involve the whole sole; in some instances pallor was confined to the toes or the forepart of the foot. The Samuels exercise test yielded positive results in a number of patients in whom positional color changes could not otherwise be demonstrated. It was the general experience that the pallor produced by elevation of the extremity in thromboangiitis and in surgical arterial occlusion was almost always accentuated when this test was employed. The experience at Mayo General Hospital, where the test was widely used, was that results were invariably negative in Raynaud's disease and in thrombophlebitis.
ExerciseTest for the Upper Extremity
The exercise test employed for the upper extremities was the counterpart of the Samuels' plantar test for the lower extremities. The patient elevated his hands with palms directed toward the observer and flexed and extended his fingers for 2 minutes. Blanching occurred in areas affected by arterial obstruction of any origin, while areas to which the blood supply was normal kept their normal pinkish tinge. When stellate ganglionectomy was contemplated, this test, following injection of the stellate ganglion with 1-percent procaine solution, furnished some evidence of the results to be anticipated from the operation.
30
IschemicPain Test (Schecter and Ragan)
The ischemic pain test for diagnostic use in peripheral vascular disease was devised by Capt. Adolph A. Schecter and Maj. Charles A. Ragan 4 in the Mediterranean Theater of Operations, when trenchfoot had become a serious problem there. With the patient recumbent, the cuff of a sphygmomanometer was placed around the leg just above the knee and the pressure within it elevated enough to obliterate the gross arterial flow (usually 220 mm. of mercury). Occlusion of the blood flow was continued for a maximal period of 5 minutes during which time the patient described any unusual sensation in the limb. After a 5-minute rest period the arterial supply was again occluded for a maximal period of 5 minutes and this time the patient flexed and extended the foot once every 3 seconds. In this period he again described any unusual sensation. The results of the test were considered positive if the patient complained of pain in or around the base of the toes in the region of the metatarsal or longitudinal arch of the foot as distinguished from pain on the dorsum of the foot at the level of the malleoli and along the anterior surface of the lower leg which is the pain caused by exercise.
The results of this test were too variable to permit much reliance to be placed upon it in the study of patients with vascular lesions. The time of onset and the intensity of the pain after occlusion of the blood supply could not be correlated definitely with other diagnostic criteria or with the actual progress of patients with trenchfoot. Moreover, a control study of normal individuals revealed that minor sensations which they described while the test was in progress could be interpreted as similar to, or identical with, those experienced by patients with trenchfoot.
Another consideration which made the ischemic pain test of questionable value was that its results depended upon the patient's subjective interpretation of his experience. Prolonged observation of patients with trenchfoot made it clear that a fair evaluation of their subjective complaints was most difficult. With continuous hospitalization even slight complaints tended to become intensified in their minds, and only men of strong character and high morale were likely to resist the subconscious temptation to enlarge on their troubles when they were given the opportunity offered by this test.
DorsiflexionTest (Homans)
Homans' dorsiflexion test, which is widely used in civilian practice in the diagnosis of thrombosis of the deep veins of the leg and foot, was also widely used in the vascular centers. The results were regarded as positive if pain occurred in the calf muscles when the foot was placed in dorsiflexion. Compression of the plantar portion of the foot was also practiced to determine whether pain would be produced in it by this maneuver. In military practice this test was often found to yield positive results in the absence of thrombosis
4 Ragan, C., and Schecter, A. E.: Clinical observations on early trenchfoot. M. Bull. Mediterranean Theat. Op. 3: 264-266, Jun 1945.
31
if there had been trauma to the leg,particularly to the calf muscles or to the Achilles tendon.
Other Tests
Occlusion of the direct flow of blood between the artery and vein involved in an arteriovenous fistula, by pressure at or proximal to the fistula, gave rise to two phenomena which were elicited as part, of the special vascular examination. Branham's (Nicoladoni's) sign is a temporary reduction in the pulse rate following occlusion. It was present in all arteriovenous fistulas observed at the vascular centers except for a few in which the opening between the artery and vein was extremely small. Studies at the vascular center of Ashford General Hospital showed that this sign did not occur when atropine in appropriate dosages was administered intravenously before digital compression was applied.
Gunderman's sign is a transient rise in the diastolic blood pressure following digital compression of the artery. The systolic blood pressure is either unaltered or only slightly elevated. This sign was present in all the arteriovenous fistulas observed at the vascular centers unless the opening between the artery and the vein was unusually small.
TESTS OF THECOLLATERAL CIRCULATION
The extent and adequacy of the collateral circulation was a matter of great significance in the diagnosis, management, and prognosis of vascular lesions. It was determined by a variety of tests and observations including Delbet's test, observation of the effect of prolonged compression of the artery involved in an aneurysm or arteriovenous fistula, reactive hyperemia tests, the claudication time test, and the reflex vasodilatation test. A number of other clinical tests were introduced at the vascular centers but proved unreliable and were not widely employed. Additional studies of the collateral circulation were made by special methods such as arteriography and determinations of intravascular pressure during operation. These methods will be described later in this chapter under appropriate headings.
The safety of an operative procedure, predicated on preoperative studies which indicated the existence of an adequate collateral circulation, was based on the premise that no important collateral vessels would be sacrificed during operation. If this condition was not met, disaster was likely to follow.
Delbet's Sign
Delbet's sign 5 is the clinical evidence of adequate circulation distal to an aneurysm, even in the absence of distal arterial pulsations in the part. When this sign was present the collateral circulation could be assumed to be good. Its presence was of particular value in aneurysms. It was repeatedly observed, even when the arterial pulses had disappeared distal to the lesion, that if good circulation had been maintained in the limb, ligation of a major artery was unlikely to be followed by any ischemic difficulties.
5 Delbet, P.: Extirpation d'un an?vrisme poplit?; gu?rison. Bull. et m?m. Soc. de chir. de Paris35: 865-870, 1909.
32
In some cases observed at the vascular centers Delbet's sign was not present originally but appeared after sympathetic block or sympathectomy had been performed. It was often present in high subcutaneous ruptured aneurysms in which other tests for the collateral circulation could not be satisfactorily performed because of the great size of the aneurysm or because tenderness and pain on pressure precluded compression of the artery.
OcclusiveCompression Test
Another useful test of the adequacy of the collateral circulation was observation of the color and warmth of the hand or foot during prolonged occlusive compression of an aneurysm. If the part remained warm and of good color, good collateral circulation could be assumed. The position of the extremity during the period of occlusion was important in the evaluation of the circulatory status. It was considered necessary to assay the circulatory status of the hand or foot in positions other than the horizontal one. Marked pallor has been found to occur when the extremity was elevated, although both color and warmth would remain normal in the horizontal position during periods of compression lasting as long as 30 minutes.
When ligation of the internal carotid artery had to be performed for cavernous sinus-internal carotid fistulas or similar lesions, it was customary to determine by means of a mechanical compressor (Fig.2) whether the patient could tolerate compression of the carotid vessels, eventually for as long as 30 minutes, without symptoms. One of the chief drawbacks to the satisfactory performance of this test was the difficulty of maintaining precise and complete compression of an aneurysmal lesion over a prolonged period of time. With mechanical compressors it is often impossible to maintain exact occlusion of
Figure 2. Mechanicalcompressor for carotidartery.
33
the desired portion of the artery for a longperiod and with digital compression the fingers soonbecome exhausted.
ClaudicationTime Test
The distance that a patient with peripheral vascular disease was able to walk before the onset of annoying or incapacitating claudication proved a practical criterion of the competency of the circulation. This very simple test could be employed not only as an index of the patient's functional vascular capacity but also as a means of weighing the possible effectiveness of various therapeutic regimens including general measures, drug therapy, sympathetic block, and surgical procedures performed directly on the blood vessels. The test also proved useful after treatment, partly to determine results in the individual patient and partly for the group evaluation of various methods of management. By this means, for instance, it was possible to weigh the relative merits of quadruple ligation and excision in arteriovenous fistulas against those of restorative procedures of one kind or another.
In patients who suffered from claudication, sympathetic block with procaine hydrochloride was a useful and dependable means of determining before operation the improvement to be expected in this symptom from sympathectomy. The effect of reflex dilatation on the claudication time was also studied as an index to the element of vasospasm present and the expected results of sympathectomy.
ReactiveHyperemia Test
The combination of observation of Delbet's sign, prolonged occlusive compression of the blood supply, and the reactive hyperemia test proved a generally safe and satisfactory method of determining the adequacy of the blood supply of the part before operation. The reactive hyperemia test, which was introduced by Moschcowitz 6 in 1907 to determine the safe level for amputation in gangrene of the extremities, was proposed as a method of estimating the efficiency of the collateral circulation by Matas 7 in 1910 and has been widely used for this purpose ever since. In the vascular centers it proved particularly useful in instances of arterial aneurysms and arteriovenous fistulas in which surgical correction was contemplated.
In the performance of the test two observers always participated to be certain that the blood flow through the aneurysm or fistula had been successfully checked and to facilitate observations on color changes in the extremity.
The reactive hyperemia test was performed as follows: With the patient recumbent, the limb to be tested was elevated after which as much blood as possible was drained out of it. If the lesion was in the lower extremity, this was accomplished by applying digital pressure on the dorsal and plantar sur -
6 Moschcowitz, L.: Die Diagnose des Arterienverschlusses bei Gangraena pedis. Mitt. a. d. Grenzgeb. d. Med. u. Chir. 17: 216-228, 1907.
7 Matas, R.: Some of the problems related to the surgery of the vascular system; testing theefficiency of the collateral circulation as a preliminary to the occlusion of the great surgical arteries. Tr. Am. S. A. 28: 4-54, 1910; also inAnn. Surg. 53: 1-43, Jan 1911.
34
faces backward toward the heel and up towardthe ankle. If the lesion was in the upperextremity, the hand could be thoroughly blanched by asking the patientto make a tight fist, or bymilking the blood from the fingers and hand by the same procedureemployed in the foot. Themilking maneuver was continued until adequate blanching had beenobtained.
A blood pressure cuff, which had previously been applied about the limb distal to the aneurysm or fistula, was then quickly inflated to a pressure of 200 to 220 mm. of mercury and complete interruption of the arterial inflow below this level achieved. The hand or foot, which by now was extremely pale, was lowered to a comfortable horizontal position. Before the test the most distal point at which digital compression of the artery completely stilled the aneurysm or fistula had been determined. This was indicated by absence of pulsation, thrill, and bruit. Four minutes after inflation of the blood pressure cuff, digital pressure was applied to this predetermined area and was maintained for 3 minutes during which the absence of pulsation and thrill was checked by palpation and the absence of bruit by auscultation. One minute after digital pressure had been applied (that is, 5 minutes after occlusive pressure had been produced by means of blood pressure cuff), the cuff was suddenly deflated and the rapidity, completeness, and intensity of the resulting flush were observed and recorded in seconds. The time interval which elapsed before hyperemia began in the most distal portion of the extremity, that is in the digits which it reached last, was recorded and the number of seconds which elapsed before it became complete in extent and in intensity was also recorded. After digital pressure was released, it was noted whether any further improvement occurred in the completeness or intensity of the hyperemia. If full and complete hyperemia occurred in less than 2 minutes, the collateral circulation was regarded as adequate.
The basal conditions under which the reactive hyperemia test was performed, as well as the precise technique, were matters of considerable importance. Reactive hyperemia was always more pronounced when the limb to be tested was in a state of vasodilatation rather than of vasoconstriction. In the absence of sympathetic denervation, limbs which were the site of aneurysms or arteriovenous fistulas were, like normal limbs, capable of a wide variation in vascular tonus. On the other hand, in deciding at the vascular centers whether the test should be performed under conditions conducive to vasodilatation or vasoconstriction, it was concluded that the initial test should be performed in circumstances which would induce neither vasodilatation nor vasoconstriction, for the practical reasons that the patient was destined to live in an ordinary environment after the test and that constant maintenance of vasodilatation could not be assured unless sympathectomy was performed.
Although Matas had determined that the reactive hyperemia test could be carried out with a blood pressure cuff, he believed that an Esmarch bandage was preferable because it brought about a more complete deprivation of blood and therefore a more intense reaction. In the vascular centers, however,
35
compression by the Esmarch bandage wasreserved for those unusual cases in which adequateblanching of the limb could not otherwise be achieved, and even inthese instances it was usedonly to milk the blood out of the limb; obstruction of the blood flowwas maintained by means ofthe blood pressure cuff.
Digital rather than mechanical compression of the artery was preferred because more accurate occlusion could be achieved with less hazard of compressing adjacent or collateral vessels at the same time. Much emphasis was placed upon complete compression of the lesion. If this was not achieved and some blood still flowed through the compressed vessels, faulty deductions concerning the efficacy of the collateral circulation were likely to be made with disastrous consequences.
The site of compression of the artery was selected with great care since the most distal point at which digital occlusion produced cessation of pulsation, thrill, and bruit was taken to represent that portion of the artery which opened into the aneurysmal sac or communicated with the vein or sac in instances of arteriovenous fistulas. This was therefore the point at which, unless a reparative procedure could be performed, it would be necessary to ligate the artery.
Compression of the artery at some point proximal to the optimum point, though it might bring about cessation of pulsation, thrill, and bruit, could give rise to misleading conclusions. On the one hand, it might occlude the blood flow through collateral vessels which would be preserved if operative ligation proved necessary; the test would therefore demonstrate less adequate collateral circulation than actually existed. On the other hand, compression proximal to the aneurysm might leave open collateral channels which it might be necessary to sacrifice at operation; the test would therefore suggest that the collateral circulation was better than was actually the case. In one instance the misinterpretation apparently arose chiefly from transmission of pressure to the laminated thrombus in a saccular aneurysm. Incorrect interpretation might, also result when the collateral channels were so located that the aneurysm could not be stilled by pressure without direct compression of these vessels also.
Misleading or actually erroneous concepts could be derived from the reactive hyperemia test if an uninvolved main arterial stem was compressed together with a minor artery which was the site of the lesion. Even under these circumstances, however, it was sometimes possible to locate the lesion definitely and to demonstrate that pulsation, thrill, and bruit could be eliminated while at the same time the blood flow in the main arterial stems remained unaffected. When this could be demonstrated there was little need for anxiety concerning the nutrition of the part after excision of the lesion.
It was sometimes possible, in a patient who presumably had an axillary aneurysm or arteriovenous fistula, to demonstrate that the lesion actually involved the thoracoacromial trunk, the subscapular vessels, or other branches. However, in a single instance the lesion involved not only a minor branch but also the main artery. The patient, observed at the vascular center of Mayo General Hospital, was a 41-year-old soldier who had an arteriovenous fistula
36
of 6 months duration which was thought toinvolve one of the circumflex humeral vessels. Bruitand thrill could be eliminated by direct pressure without disturbingthe brachial pulse. Duringoperation it was found, as had been thought, that the anteriorcircumflex humeral artery and veincommunicated through a small sac, but it was also found, as had notbeen suspected, that thesuperior portion of the axillary artery opened into this sac through alarge fistula. The confusionarose because it had been possible to compress the sac in such a mannerthat the openings fromthe two arteries and the vein were occluded while the axillary arteryitself was left patent.Ligation was required because the damage to the axillary artery was tooextensive to permitrepair. Consequently, the efficacy of the collateral circulation had tobe confirmed during theoperation by observing the color and warmth of the hand duringprolonged temporary occlusionof the axillary artery with a rubber-shod clamp.
The reactive hyperemia test was frequently performed serially before and after induction of reflex vasodilatation, or before and after sympathetic block or sympathectomy. It was by no means uncommon for a test which had indicated inadequate circulation before one or the other of these procedures, to indicate an adequate circulation after removal of the vasoconstrictor influence.
MiscellaneousTests of the Collateral Circulation
The tests already described were those chiefly used to test the adequacy of the collateral circulation in the presence of vascular lesions. Two other tests were tried out but were not found sufficiently useful to warrant their continued use. The first was performed by milking the blood from the subpapillary venous plexus by compressing the arterial lesion while rolling a snugly fitting rubber band from the tip of a digit to its base, then noting the time required for return of color after release of the constricting band. Results were not uniformly in accord with the time components of the reactive hyperemia test. Another test in this category was performed by simultaneous digital pressure upon the arterial lesion and on some area on a finger or a toe. The time in seconds required for the return of color was compared with the time required for the return of color in the same digital area in the contralateral limb. The test was also carried out without compression of the arterial lesion. The results of this test, like those of the preceding, were not uniformly in accord with the time components of the reactive hyperemia test.
TESTS OFVENOUS FILLING TIME
The simple venous filling test proved of considerable value in demonstrating the rate of circulation in an extremity. It was performed by first elevating the extremity to collapse the veins, then replacing it in the dependent position and noting in seconds the time required to fill the veins on the dorsum of the
37
hand or foot. Periods up to 10 seconds were considered within the normal range.
However, unreliable results were obtained from this test when vasospasm was present since arterial inflow is slow under these circumstances. Moreover, the results did not distinguish between reduction of blood flow caused by organic arterial involvement and that caused by vasospasm. In order to obtain this differentiation it was necessary to perform the test after injecting 1-percent procaine solution into the appropriate sympathetic ganglia, a supplemental procedure which also furnished useful data concerning the results to be expected from sympathectomy.
The modification of the simple venous filling time test devised by Tuffier and Hallion in 19128 was particularly intended for use in aneurysms and arteriovenous fistulas. As the test was performed at the vascular centers the limb was elevated 30 degrees above horizontal and kept in that position until the veins were well emptied. The aneurysm or arteriovenous fistula, was then occluded by digital pressure and a blood pressure cuff, previously placed about the limb distal to the lesion, was inflated to a pressure of 60 mm. of mercury after which the limb was lowered to the horizontal position. If the veins filled within 30 to 60 seconds the collateral circulation was regarded as adequate.
Experience at the vascular centers revealed certain defects in this test. When edema or venous stasis was part of the picture the results were likely to be unreliable. If the veins did not fill well, as frequently happened when vasospasm was marked, an accurate estimation of the venous filling time was impossible. Finally, in some patients, particularly those with large arteriovenous fistulas, venous filling sometimes occurred as soon as the fistula was compressed even though the limb was elevated.
A test to determine the adequacy of the circulation in the fingers or toes (subpapillary venous filling time) was carried out by making firm digital pressure against the ball of the digit for about 3 minutes to empty the blood from the subpapillary venous plexuses. Pressure was then released and the time required for the area to flush was recorded as immediate or normal, slightly or moderately delayed, and markedly delayed.
TESTS FORSPECIAL CONDITIONS
Varicosities. All the tests employed in Army hospitals to determine the competency of venous valves and the patency of superficial or deep veins are well known and have been extensively used for many years. No new or significant data resulted from their use during World War II. The tests most commonly employed were the Perthes test, the Trendelenburg or Brodie-Trendelenburg test, and the Ochsner-Mahorner comparative tourniquet tests. At the vascular center of Mayo General Hospital it was thought that simple
8 Tuffier and Hallion: Sur un proc?d? permettant de pr?voir que 1'irrigation sanguine persistera dans un membre apr?s ligature de son art?re principale. Compt. rend. Soc. de biol. 73: 606, Dec 1912.
38
observation of venous filling with thetourniquet at various levels of the extremity was morehelpful than any other method in determining the site of vascularincompetency in patients withvaricose veins.
Scalenus Anticus Syndrome. The scalenus anticus test was used to study the effect upon the subclavian artery of an abnormally small compartment formed by the scalenus anticus muscle and the first rib. Results of this test were regarded as positive if diminution of radial arterial pulsation could be demonstrated while the patient turned his head toward the unaffected side with the chin extended upward. Another test consisted of pulling upward against a weight held in the hand on the affected side in an attempt to extend the arm tensely upward. Diminution of the pulsation of the radial pulse could be demonstrated in this test also. Sole reliance was not placed upon palpation of the pulse or the appearance of the extremity; a cuff was placed over the brachial artery before the test was begun, and additional comparative data secured by means of an oscillometer while it was in progress. In patients with the scalenus anticus syndrome significant tenderness or spasm could sometimes be revealed by simple palpation of the muscle.
Procaine hydrochloride solution was injected into the scalenus anticus muscle in order to confirm the tentative diagnosis of scalenus anticus syndrome and to ascertain the possible effects of scalenotomy. If relief of subjective and objective symptoms followed the injection, the diagnosis was regarded as established and it was concluded that scalenotomy would be beneficial.
Before the solution was injected, the patient was placed in a recumbent position with the head turned to the unaffected side. The scalenus anticus muscle was identified by palpation behind and lateral to the sternomastoid muscle. While the index finger of the left hand palpated the lateral border of the muscle, a needle was inserted into the lateral edge and the muscle was infiltrated with 1-percent procaine solution throughout the lower half, care being taken not to infiltrate the phrenic nerve or brachial plexus. Within 5 to 10 minutes it was usual to find the muscle completely relaxed and the patient temporarily relieved of his symptoms.
Axillary Vein Thrombosis. The objective of tests for axillary vein thrombosis was to demonstrate interference with the return flow of blood from the arm. One very simple test was to observe whether or not the veins collapsed when the patient elevated the affected arm. If thrombosis was present they did not collapse. In another test the patient opened and closed the hands in a pumping motion while the arms were dependent. If thrombosis was present the superficial veins of the forearm became overdistended on the thrombosed side, while on the normal side distention did not occur.
SKINTEMPERATURE DETERMINATIONS
Since sweating or moisture alters the results of skin temperature readings, all such determinations at the vascular centers were made in rooms in which
39
temperature and humidity were controllable. The room temperature was kept between 68o and 78o F. and the humidity at 40 percent for basal tests. Readings were made only after the patients had been exposed to this environment for 30 minutes.
Skin temperature determinations were chiefly of value in supplying an objective recording of the actual temperature of a part. They were seldom required for mere diagnosis though they were both valuable and necessary in such difficult diagnostic problems as the determination of possible differences in the mechanism of circulatory disturbances in one extremity as compared to the contralateral one, or in one digit as compared to others. They were also useful in cases in which it was necessary to determine whether the disorder was purely obliterative, had a vasospastic element, or was entirely vasospastic.
Several types of skin temperature meters were in use at the vascular centers. Although all were probably equally efficient, preference as to type varied from center to center.
The skin temperature of certain points on the body was taken routinely in addition to the temperature of whatever special areas might be implicated in the individual patient. The areas tested in the lower extremity were the dorsum of the terminal phalangeal area of each toe, the middorsal area, the midplantar surface, the heel, the intermalleolar region, the ankle, the midleg, the knee, and the midthigh. In the upper extremity the test points were the distal phalangeal portion of each finger, the midpalm, the middorsum, the wrist anteriorly, the midforearm anteriorly, the medial aspect of the elbow, and the midportion of the upper arm anteriorly. A chart indicating each of these points was posted in the controlled temperature rooms to assure uniformity in the skin temperature determinations. Even minute variations in the points at which control and subsequent determinations were made might affect the results. For this reason it was customary to mark with ink or dye the exact points at which initial readings were made so that subsequent readings could be made at precisely the same points. When this precaution was not observed, errors of as much as several degrees Fahrenheit sometimes occurred. The opinion was that such variations might possibly be accounted for by the presence of sizable intracutaneous capillaries at one point and not at another, even though the points of reading might not be more than a millimeter apart.
Psychogenic factors such as nervous tension, excitement, and noise, were found to have a decided influence on skin temperature readings. Every effort was therefore made to reassure the patient and put him at ease. All controlled temperature rooms in which tests were made were soundproof. Repeated determinations were made in cases in which the initial readings were thought to be inaccurate for any of the reasons listed. Successive temperature determinations were also made in some cases to study the effect of changes in the room temperature (Chart 1).
40
OSCILLOMETRY
Oscillometric studies were carried out with various instruments such as the Collins nonrecording oscillometer, the Samuels pulsimeter, and the Boullitte, Pechon, and Tycos instruments.
When the manual nonrecording method was used, the cuff of the oscillometer was inflated until the pulse in the extremity was completely obliterated. At this point readings were taken at 10-mm. levels until 0 pressure was reached. In the lower extremity readings were made in the foot, above the ankle, in the leg, at the popliteal level, and at the midthigh. In the upper extremity readings were taken at the wrist, in the forearm, and in the arm. The maximum oscillation and the level in millimeters at which it was observed were recorded as the oscillometric index (for example, a. 7.5 oscillation at 100 mm. was recorded as 7.5/100).
When the recording oscillometer was used, a record was made of oscillations from the level of the pressure at which obliteration of the artery occurred to 0. Readings were in millimeters of mercury. The curves recorded were studied for amplitude and character.
41
The opinion was expressed at all three vascular centers that while the oscillometer was of some value in the diagnosis of vascular lesions it was neither too reliable nor too useful. The following general observations were made:
1. Most of the patients who had been referred to the vascular centers merely because no dorsalis pedis pulse could be felt on either side in the usual location were found to have better than normal oscillometric readings across the feet. It was the impression that in these patients the lack of detectable dorsalis pedis pulses could be explained by a developmental absence of an anomalous position of the artery.
2. The oscillometer, while seldom necessary for the establishment of a diagnosis or for the evaluation of treatment, was useful in providing an objective recording of the volume of the larger peripheral pulsations and in an occasional difficult diagnostic problem. It was sometimes of value in demonstrating whether obliteration had occurred in a large arterial stem, especially when there were palpable peripheral pulses in the involved limb. This was true in spite of the instrumental lag or error inherent in the test.
3. The oscillometer recorded only gross pulsations as compared with the plethysmographic record which indicated quick pulse volume changes as small as 0.1 cu. mm., or more gradual changes as great as 800 cubic millimeters.
4. The oscillometer was found to give misleading information in arteriosclerosis, and to a lesser degree in thromboangiitis, in that oscillations were sometimes found to be small or absent even when there was a fair or a good arteriolar and capillary circulation. The explanation is obvious: The oscillometer does not depict the circulation in the smaller vessels. Oscillometric readings alone, therefore, could not be accepted as an index of circulatory adequacy but had to be interpreted in the light of other observations.
5. Oscillometric studies of patients with thromboangiitis obliterans frequently proved interesting because they revealed consistent asymmetry of the oscillations of the contralateral limb even when the readings on the poorer side were still within normal limits. This was observed consistently enough to be accepted as a sign in. thromboangiitis obliterans. Patients with clinical evidence of migratory thrombophlebitis, but without symptoms of arterial incapacity, also usually presented early asymmetry of oscillations.
6. Oscillometric readings frequently were within the normal limits in patients with trenchfoot and Raynaud's disease.
7. In a number of cases of thromboangiitis obliterans, oscillometric readings were normal even when there were clear-cut signs of impaired circulation in the toes, such as trophic and color changes. It was believed that in these cases the disease had affected only the smaller vessels. In other patients oscillations were reduced in the absence of color changes, while the results of such tests as the reactive hyperemia test and the reflex vasodilatation test showed that the circulation was still normal. In these cases it was thought that occlusion of a large vessel had occurred but that adequate circulation was being maintained through collateral vessels.
42
SWEATINGTESTS
Various tests were employed for the accurate demarcation of areas in which sweating did not occur or was excessive. They were most frequently used in hyperhidrosis, including the variety associated with trenchfoot, but they were also useful in any other condition in which abnormalities of sweating were apparent. They were employed for diagnostic purposes to determine the possible effects of sympathectomy, and as an index of the patient's progress. The starch-iodine test was most useful.
VENOUSPRESSURE DETERMINATIONS
Venous pressure determinations were made in an extensive series of cases at the vascular center of DeWitt General Hospital but furnished no important information except in an occasional case of arteriovenous fistula or arterial aneurysm which was causing pressure on an adjacent vein, or in an occasional case of venous obstruction resulting from either thrombosis or surgical ligation. These determinations were thought to be particularly significant in cases of suspected superior vena cava thrombosis and axillary vein thrombosis.
The only equipment necessary was a venous pressure manometer. Observations were made during rest and during or immediately following exercise. Determinations on patients with thrombophlebitis were sometimes normal in the resting stage while repetition of the test during or after exercise confirmed the suspected obliteration of the veins. In such cases the venous pressure rose above and did not return to the control level for 2 to 3 minutes.
At Ashford General Hospital venous pressure determinations were made in some cases by direct mensuration at the site of an arteriovenous fistula by the introduction of a ureteral catheter through an appropriate vein in the region of the fistula.
DETERMINATIONOF THE CIRCULATION TIME
Measurements of the circulation time were made through the introduction of a foreign substance into the blood stream at one point and subjective or objective perception of the time of its arrival at another point. At the DeWitt General Hospital equipment was supplied for the determination of the circulation time by the photoelectric-methylene blue method, but it was concluded that the information supplied by this, as well as by other methods, was not of much practical value.
BLOOD VOLUMEDETERMINATIONS
Blood volume determinations were frequently made before and after operation, particularly in patients with arteriovenous fistulas. These studies confirmed earlier observations to the effect that there is an increase in the blood volume in response to the presence of an arteriovenous fistula and a
43
return to the normal level following obliteration of the communication. Special studies with the dye dilution method and with the ballistocardiograph were made at the Ashford General Hospital and are reported in full in Chapter V.
SKINRESISTANCE DETERMINATIONS
Determinations of the skin resistance were made in a limited number of cases by means of a portable cutaneous resistance recorder or dermometer. Although this method proved of no practical value in the evaluation of the vascular status of patients with vascular injuries or disease, it did provide significant data concerning the influence of the sympathetic nerves on the vascular system and the possible effectiveness of sympathetic nerve block and sympathectomy.
PLETHYSMOGRAPHY
It was intended that each of the vascular centers would be supplied with plethysmographs, but these instruments did not reach the point of production and distribution before the end of the war. Although the vascular centers at Ashford and Mayo were able to acquire this instrument, the center at DeWitt, to which the author (A. H. S.) was assigned, was without one during the entire period of its operation. This was unfortunate for while no patient suffered because the instrument was lacking, investigation of the vascular status of many patients would have been expedited had it been available.
This instrument is capable of recording with great quantitative accuracy volume changes in the part under investigation caused by variations in the blood within the small arteries and the arterioles, venules, and capillaries, as well as changes in the intercellular and extracellular fluid and lymph. Plethysmographic recordings reveal with greater accuracy than any other method the differentiation between vasospastic phenomena and phenomena caused by organic occlusive disease, the degree of arterial patency or occlusion, the state of the collateral circulation, and the benefits to be expected from sympathectomy (the latter evaluation being made from observation of the changes produced by sympathetic procaine block).
Plethysmographic studies are reliable only if the test is made under standard conditions. The relative height of the part under investigation greatly influences both the magnitude and the character of volume deflections. All examinations are therefore made with the part in question at heart level. In the recumbent position the toes are essentially at this level, and the fingers are so supported during the test that they are also at this level. The extremity cups must not touch each other since if they do artefacts will occur. The patient must be comfortable for any discomfort will result in tremors and other movements which will be recorded as artefacts. The maximum amount of mental relaxation is essential because psychic disturbances are always reflected in the vascular response. For this reason noise, haste, excitement.
44
and even the sight of the instrument should be guarded against and the examination should be made under optimum conditions to produce relaxation. These conditions include indirect lighting, a comfortable room temperature, ordinary room furnishings, and calm and confidence on the part of the examiner. If plethysmographic studies are done under any other circumstances, they must be interpreted in the light of the environment.
WHEAL TESTS
The intradermal saline test was employed in a number of cases in an endeavor to determine the adequacy of the collateral circulation in patients with vascular injuries and disease, but it did not prove practical. In this test, if the circulation is good, the wheal should persist for nearly an hour but accurate compression of an artery for this period of time is almost impossible.
The histamine wheal test, which was also devised to estimate the efficiency of the collateral circulation, was not highly regarded at the vascular centers for it revealed nothing which could not be determined equally well by other means, and sloughs of tissue at the site of the injection, sometimes accompanied by ulceration, contraindicated its general use. After the aneurysm or the vessels involved in an arteriovenous fistula had been occluded by digital compression, a drop of 1:1,000 solution of histamine phosphate was placed on the skin of the affected extremity and the area was needled through the drop until a wheal developed. If the collateral circulation was good, the wheal was apparent in 3 to 5 minutes. It was thought that the prompt occurrence of a flare prior to the development of the wheal was as important as the latter phenomenon.
Fluorescin Wheal Test
A method for determining the adequacy of the collateral circulation by means of fluorescin wheal testing was employed with considerable satisfaction at the DeWitt General Hospital by Capt. Theodore B. Massell. 9 It was based on the similar test developed by Neller and Schmidt 10 to determine the safe level for amputation in limbs which were the site of impending or early gangrene. These observers found that when fluorescin was injected into the veins, sites of minute trauma in an area in which the peripheral circulation was not severely impaired would display brilliant fluorescence, but that no fluorescence would appear if the circulation was inadequate to supply the normal metabolic needs of the tissues. They further found that the area of fluorescence corresponded to the wheal component of triple response to injury as described by Lewis.11
9 Massell, T. B.: The fluorescin wheal test for collateral circulation in the preoperative evaluation of patients with aneurysms and arteriovenous fistulas. Surgery 21: 636-645, May 1947.
10 Neller, J. L., and Schmidt, E. R.: Wheal-fluorescence; new method of evaluating peripheral vascular diseases; preliminary report. Ann. Surg. 121: 328-337, Mar 1945.
11 Lewis, Thomas: Vascular Disorders of the Limbs Described for Practitioners and Students. New York, The Macmillan Company, 1936.
45
This method was used at the DeWitt General Hospital in a small series of cases to study the vascularity of granulating wounds, particularly in cases of trenchfoot in which there had been spontaneous or surgical amputation of the toes with subsequent granulation of wound surfaces. It was hoped that observations by this method might indicate the degree of vascularization of the granulating tissue more decisively than simple clinical observation, and would thus serve as an index of the optimum time for skin grafting. In the 55 cases in which this method was used to determine the adequacy of the collateral circulation in aneurysms and arteriovenous fistulas, the results were found to be reliable. They so closely paralleled clinical impressions gained by simple inspection, however, that the time and trouble necessary to perform the fluorescin test were not considered justified.
The following conclusions concerning this test were reached at the vascular center of DeWitt General Hospital:
Wheal fluorescence provides a delineation of the end-point of adequate circulation. Comparison is usually possible with the opposite normal extremity so that a control criterion is constantly provided. Movement of the extremity is not necessary during the test and as a result there is little danger that the compressor may slip and erroneous conclusions concerning the collateral circulation be drawn.
Three defects exist in the test which are, however, also present in the reactive hyperemia test:
l. It has limited use in cases in which the compressor cannot be tolerated for anatomic reasons, or in cases in which a sensory nerve is involved in scar tissue at the site of the lesion and compression cannot be tolerated.
2. The compressor may occlude an important collateral branch in the immediate vicinity of the aneurysm.
3. It does not indicate how much activity a patient may enjoy following arterial ligation. Although the collateral circulation may be sufficient to prevent gangrene, ligation of a major artery often results in marked limitation of exercise tolerance because of weakness in an upper extremity or intermittent claudication in a lower extremity. The experience at the vascular center of DeWitt General Hospital suggested, however, that claudication was likely to be more severe in patients whose circulation, by the fluorescin wheal test, was barely adequate rather than good.
TESTS OFVASOMOTOR TONE AND LABILITY OR REACTIVITY
The frequent need for differentiation of vasospastic from obliterative vascular lesions, as well as the need for demonstration of a vasospastic element associated with organic obliterative lesions, required extensive employment at the vasular centers of various methods of testing for the degree of vascular tone and vasomotor lability. Tests most frequently used for this purpose were the reflex vasodilatation test, the basal vascular tone test, immersion of the
46
hands or feet in ice water, Kerr's triggerreflex test, the cold shower test, and general bodycooling test. The specialized technical procedures used for the samepurpose, including spinalanalgesia, sympathetic block, and peripheral nerve block, are discussedlater in this chapterunder the heading "Nerve Conduction Interruption Tests."
The reflex vasodilatation test employed extensively at all centers in both vasospastic and obliterative vascular lesions was carried out as follows: The patient was placed in a controlled temperature room in which the temperature was maintained from 68o to 72o Fahrenheit. The distal portion of the extremity to be studied was exposed to this temperature for at least 20 minutes, following which skin temperature determinations were made. Seven or eight hot water bags, filled with water as hot as could be tolerated, were then placed in the axillae and about the abdomen and the patient was wrapped in blankets except for the extremity being studied which was left exposed to the environmental temperature. When it was more convenient a portable body baker was used in place of the hot water bags and blankets. As soon as profuse sweating became evident, skin temperature determinations were made, and repeated at 20-minute intervals for at least an hour and a half.
In the normal person there was a rise of temperature in the digits to between 87.80o and 95o Fahrenheit. This type of response, associated with reduced oscillometric readings, was interpreted to mean that the collateral circulation was good. In the patient with occlusive vascular disease the temperature rise in the digits after body heating was usually only slightly above control initial levels.
The degree of reflex vasodilatation was also useful for studying relief of rest pain and increase in functional capacity as evidenced by lessening of claudication. A modification of this method was employed to test the reactivity to heat and cold. The patient was conditioned for 30 minutes in a controlled temperature room at 75o F. with the humidity kept at minimum saturation. Initial observations of the skin surface temperatures of the upper and lower extremities, together with oscillometric observations, were made for control purposes. The room temperature was then lowered to 65o F. and the patient kept in this environment for 45 minutes. Additional observations of the skin surface temperatures and additional oscillometric studies were made at this time, and repeated after the temperature of the room had been elevated to 85? F. and the patient exposed to this environment for 45 to 60 minutes. Curves were plotted to show graphically the response to environmental changes.
In still another method of testing, the patient was first placed in a controlled temperature room in which temperature was maintained between 68o and 71o F. with the distal portion of the extremity to be studied exposed to the room environment. At the end of 30 minutes, control skin temperature readings were obtained. The patient was then taken into a cold room (usually a large icebox used for the storage of food) in which the temperature varied between
47
32o and 14o Fahrenheit. He was accompanied by an observer who recorded changes in the appearance of the digits and any symptoms which might develop. At the end of 15 to 20 minutes he was returned to the controlled temperature room where skin temperature readings were repeated.
The precipitation of digital syncope and other symptoms by immersion of the hands or feet in ice water was attempted in patients with Raynaud's disease or other vasospastic conditions. Many patients, however, in whom digital syncope occurred when they went out of doors on a cool day failed to exhibit demarcated pallor following immersion of the affected part in ice water. This experience, which occurred at all the vascular centers, was contrary to what was expected and was never satisfactorily explained. It meant, however, that other methods of inducing digital ischemia had to be resorted to.
Kerr's trigger reflex test was used at the vascular center of DeWitt General Hospital where it proved extremely useful in Raynaud's disease. Both hands were immersed simultaneously, one in water at 59o F. and the other in ice water to which enough salt had been added to reduce the temperature to about 34o Fahrenheit. Invariably the hand immersed in ice water became and remained crimson, while the hand immersed in cool water (59o F.) usually became cyanotic as the result of spasm brought on by moderate cooling.
Chilling the entire body in a cold shower bath for 2 minutes almost invariably induced digital syncope in the hands of patients with Raynaud's disease although exposure to room temperature of 48o F. in a controlled temperature room, like immersion of the affected part in ice water, frequently failed to produce this result.
One method employed to determine the degree to which vasospasm contributed to the circulatory stasis was the application of heat to the contralateral unaffected extremity and the measurement of the height to which the temperature (reflex) rose in the affected extremity.
The injection of typhoid vaccine was occasionally employed to release vasoconstriction and to determine capillary dilatability. The ratio between the elevation in the oral temperature and the elevation in the temperature of the extremities following its use was termed the vasomotor index. The test is obviously not selective and was not regarded as of great value in the few cases in which it was employed.
NERVECONDUCTION INTERRUPTION TESTS
SympatheticGanglion Block
Chemical interruption of sympathetic nerve conduction by means of sympathetic ganglion blocks was considered an extremely reliable test at the vascular centers of Mayo and DeWitt General Hospitals where this method was extensively employed. It was regarded as of special value for indicating the contribution of vasospasm to circulatory deficiency and in providing
48
indications of what might be expected fromsympathectomy. At the vascular center of AshfordGeneral Hospital sympathetic block was not thought to be either aspractical or as reliable as thespinal analgesia vasomotor test.
Even at the centers in which nerve block was looked upon with favor, however, its limitations were realized. Like all tests for vasospasm it was useful simply in ruling out vascular occlusions. None of these tests indicated the degree of positive vasomotor activity with which the patient would respond to environmental factors or to psychogenic influences.
At DeWitt General Hospital when the lesion was in the lower extremity 1-percent procaine solution was injected into the first, second, third, and fourth lumbar ganglia first on one side and then on the other. At Mayo 1/2-percent procaine was injected singly at the level of the first or second sympathetic ganglion. At DeWitt when the lesion was in the upper extremity procaine was injected into the stellate ganglion, but at Mayo the block was carried out posteriorly at the level of the first dorsal ganglion.
Peripheral Nerve Block
The experience at DeWitt General Hospital warranted the conclusion that observation of the effects of peripheral nerve block on pain, color, temperature, and functional capacity was essential in ruling out arterial occlusion whenever the skin temperature of the affected part did not rise considerably following the application of heat to the body or following sympathetic ganglion block.
The Use of Anesthetic Agents for Testing Purposes
Neither general nor intravenous anesthesia was used for vasomotor testing at any of the vascular centers. Spinal analgesia was employed extensively at Ashford General Hospital where it was thought to be more consistently reliable than sympathetic ganglion blocks and to be attended with fewer complications or unsuccessful results. It was the belief at the other centers that the lowering of the blood pressure likely to occur after induction of spinal analgesia made this test less reliable than selective chemical interruption of sympathetic nerve conduction by sympathetic ganglion blocks.
Spinal analgesia was induced in a patient without preliminary medication and with his stomach empty, after he had been in the controlled temperature room for 30 minutes. At this time control readings of the skin temperature of the lower extremities and oscillometric determinations were made. When they had been concluded, 100 to 120 mg. of procaine hydrochloride were injected into the spinal canal at the interspace between the spinous processes of the fourth and fifth lumbar vertebrae. Analgesia was thus established from a level midway between the umbilicus and the symphysis pubis to the toes. When the complete effects of the injection had been felt, observations were made concerning pain, color, and sweating of the extremities, and the skin temperature and oscillometric readings were repeated.
49
At the end of the test the patient was returned to his bed on a litter and was kept flat on his back, without pillows, until the following morning. There were no untoward reactions in any of the large number of cases in which the test was used at the vascular center of Ashford General Hospital.
DETERMINATIONOF THE BASAL VASCULAR TONE
Studies along the lines of those carried out by Naide12 to determine the basal vascular tone of patients with vascular diseases and injuries were made at the vascular center of DeWitt General Hospital in the hope that this method of investigation might furnish a more accurate index of vascular tone than could be obtained by other means. Naide had found it necessary merely to observe the skin temperature response in the finger tips during a cooling period in order to classify patients into two basic groups, those with high and those with low vascular tone. A patient was regarded as having a high vascular tone if the hands were cool (below 77o F.) after he had spent 15 minutes, clothed only in a light gown, in a controlled temperature room at 68o Fahrenheit. If, on the contrary, the hands remained warm (77o F. or above) after the exposure, the vascular tone was considered low.
The tests made at the DeWitt General Hospital were carried out during the summer in the early morning when the environmental temperature was comfortably cool. The patients were in a basal resting state, had had no breakfast, and had not been permitted to smoke before the test was made. Skin temperature measurements were made with a galvanometer in a controlled temperature room with the environmental temperature at 68o F. and the humidity at 40 percent. The digital skin temperature was measured at the start of the test and every 10 minutes thereafter over a period of an hour.
Forty-five patients with lesions of the major arteries were studied by this test, 25 before operation for aneurysms or arteriovenous fistulas, 17 after ligation of the main artery to the extremity in the course of operations on arterial lesions, and 3 after ligation of a major artery shortly after injury and development of arterial thrombosis, also after injury.
The results of the test were in agreement with the clinical impression in 32 of the 45 patients. In 10 of the 13 patients in which agreement did not exist, analysis of the end results permitted a comparison of the clinical impression and the results of the test. In 7 of these 10, the test indicated normal or low vascular tone while clinical signs clearly indicated an abnormal degree of vasoconstriction; repetition of the test in several instances did not alter the findings. In another patient the special study indicated high vascular tone while the clinical study and end results indicated absence of vasoconstriction. In the 2 remaining patients the test for basal vascular tone proved superior to the clinical appraisal. In 1 of these patients persistent symptoms of inter-
12 Naide,M.: Test for vascular tone inhumans and its application to the study of vasculardiseases with special reference to etiology andprevention ofthrombophlebitis. Am. J. M. Sc.207: 606-620, May 1944.
50
mittent claudication suggested that sympathectomy should be performed even though other clinical evidence of abnormal vasoconstriction was lacking. The other patient, in spite of clinical evidence of increased vasomotor tone, did not develop symptoms of vascular insufficiency. Possibly the fact that the arterial lesion in the latter case was situated in the midfemoral region may have facilitated the development of collateral circulation in spite of the presence of vasoconstriction.
From the experience at DeWitt General Hospital it was concluded that the test for basal vascular tone could not be relied upon alone in the selection of cases for sympathectomy since in a series of 45 cases it proved superior to clinical judgment in only 2 instances, while in 8 others reliance upon it would have dictated incorrect therapy. It was tentatively concluded that the variation in the results of the test at DeWitt General Hospital and those obtained by Naide might be explained by the difference in the character of the case material. All the patients in the Army hospitals were vigorous young individuals who had sustained local vascular trauma. This trauma might well have set up some degree of segmental vascular spasm which was independent of the general vasomotor tone.
ELECTRODIAGNOSTICSTUDIES
Electrocardiograms were made before and after operation in practically all patients with aneurysms and arteriovenous fistulas, as well as those with peripheral arteriosclerosis and thromboangiitis. The marked abnormalities commonly found in patients in civilian practice with arteriovenous fistulas of long duration were unusual among the patients with the same condition examined at the vascular centers. The explanation is undoubtedly twofold: (1) in military practice diagnosis is made early; and (2) fistulas are eliminated surgically before pronounced cardiac damage occurs.
Electro-encephalographic studies were carried out in a few cases of cavernous sinus-carotid artery fistulas both before and after compression to control the passage of blood through the affected artery, but they provided little or no information which could not be obtained by simpler methods.
ROENTGENOLOGICMETHODS
Plain Roentgenograms
Plain roentgenograms of the extremities were employed to demonstrate or exclude (1) calcification in the arteries and veins and in aneurysmal sacs, (2) foreign bodies, (3) subcutaneous trabeculation, and (4) bone changes occurring in conjunction with vascular disease or injury.
Roentgenograms of bones of the extremities often revealed changes in the functional vasospastic group as well as in the organic group of diseases. Osteomyelitis and atrophy of the terminal phalanges associated with ulceration were sometimes observed in thromboangiitis obliterans and Raynaud's disease.
51
Marked diffuse atrophic changes (osteoporosis) were sometimes observed in the severe acrocyanotic syndrome which followed some cases of trenchfoot. Whether the demineralization was the result of disuse or of a chronic decrease in blood flow remains to be explained. It was usually observed, however, that some improvement in the roentgenologic picture followed use of the limb.
Sudeck's disease, with its pattern of pain, vasospasm, and dysfunction, was associated with a mottled form of decalcification of the bones of the affected limb. The roentgenographic appearance in such cases differed from the smooth type of decalcification observed in disuse atrophy or chronic ischemia. Some observers took the position that smooth atrophy was a transient stage likely to be found in all extremities that had been immobilized for reasons of disease or injury.
Arteriography and Phlebography
Arteriography. Arteriograms (Figs. 3A, B, and C) were used extensively at the vascular center of DeWitt, occasionally at that of Mayo, and never at Ashford.At DeWitt visualization of the arteries was thought to be a valuable method of making precise studies of aneurysms and arteriovenous fistulas both before and after operation and of arteriovenous fistulas and saccular aneurysms during and after spontaneous closure. The end results of arterial reconstruction were also evaluated by this method. Thorotrast (colloidal suspension of thorium dioxide) or diodrast (iodopyracet) were the radiopaque substances used for arterial visualization and there were no serious reactions to the use of either agent, though the injection of diodrast was in a few instances followed by hot flushes, transient nausea and vomiting, or a rash which lasted only a short time. There was also an occasional local reaction. Arteriography was not used at the vascular center of Ashford General Hospital because the staff believed that arteriograms were often misleading and further that serious reactions might result from the use of the agents.
At DeWitt General Hospital both diodrast and thorotrast were used, though thorotrast was preferred if impending gangrene was feared since mild to moderate spasm occasionally followed the use of diodrast. All patients scheduled for either arteriography or phlebography were given a preliminary sublingual, conjunctival, or intravenous test with the agent to be used, and adrenalin was kept at hand for immediate use if a reaction should develop. The technique for both agents was the same. A plain roentgenogram of the extremity was usually taken before the opaque substance was injected in order to determine the optimum x-ray factors to be used.
If the lesion was in the lower extremity the groin was shaved and prepared as for surgery. All exposures were taken in the dorsal decubitus. When the femoral artery had been identified by palpation of the skin crease, a 19-gage needle was inserted and directed obliquely downward at an angle of about 45 degrees to prevent its going through both walls of the artery. As soon as the vessel wall could be felt pulsating against its tip, pressure was decreased and
52
the needle was allowed to rest in that position until with very little additional manual pressure the pulsations forced it into the vascular lumen. Then, as soon as an assistant had compressed the artery proximal to the site of puncture by digital pressure, 25 to 30 cc. of the radiopaque fluid was injected as rapidly as possible and an exposure was made with the film held either in a Bucky tray or an ordinary cassette. Pressure was then released and an attempt was made to obtain another exposure in order to visualize the more distal parts. If the artery distal to the site of an arteriovenous fistula was of small size, the collateral circulation was regarded as adequate.
Arteriograms in other regions were made by the technique described. This was modified, as necessary, to fit the regional anatomy.
Phlebography. Phlebography by means of a contrast medium was not used at Ashford General Hospital for the same reasons that arteriography was not used. It was employed, however, at the vascular centers of both Mayo and DeWitt General Hospitals, 280 examinations being made at the latter. It was the opinion of the staff at both these centers that phlebography, when used with the proper precautions, was free from risk and that it was a valuable method of determining with accuracy the location and extent of venous thrombosis, venous patency or occlusion, and the results of reparative operations on veins. It was thought to be of particular value after restorative operations on veins implicated in arteriovenous fistulas.
The patient was placed on the table in the recumbent position and two films, 14 by 17 inches, were slipped under the affected extremity. The first extended from the groin to the popliteal space and the second, which slightly
53
overlapped the first, from the poplitealspace downward. The upper film was held in a speedcassette in a Bucky tray. The lower was at first placed in a bakelitecassette with the upper metalborder removed. Later a wooden stage was employed so that the filmcould be slipped in andout without moving the leg, and a cardboard holder was substituted forthe bakelite cassette.
After the films were in position, a heavy, rubber tourniquet was placed about the upper portion of the thigh and tied just tightly enough to occlude the long saphenous vein. Results were less satisfactory when the tourniquet was-applied too tightly. Another smaller, rubber tourniquet was applied just above the ankle and tied tightly enough to make the veins on the foot stand out. The radiopaque fluid was thus prevented from flowing directly into the saphenous system. Veins on the dorsolateral aspect of the foot were preferred as the site of injection since they do not enter the saphenous system directly. Occasionally the tibial vein was exposed at the ankle and the fluid injected directly into it.
Insertion of the needle into the vein was not always easy. Sometimes the patient had to be asked to swing his foot over the side of the table into a dependent position to dilate the veins. The best results were achieved with 20-gage needles and it was important that they be sharp.
After the films had been placed, the tourniquet applied, and the needle inserted, 20 to 30 cc. of diodrast (35 percent) or thorotrast were injected slowly into the vein over a period of 30 to 45 seconds. The tourniquet about the ankle was removed just before the last 5 cc. of material were introduced. While the diodrast was being injected the position of the extremity was readjusted, if necessary, and the leg steadied so that the film could be exposed immediately upon completion of the injection. The tube was centered over the knee, or placed just above it, and the extremity was elevated to the maximum height in order that all of it might be included in the roentgenogram. X-ray factors varied with the size of the patient and the extent, location, and type of vascular lesion, but were usually as follows: tube-target distance 40 inches, milliamperes 100, kilovolts 70 to 80.
After the first picture had been taken, an assistant who had taken up his position before the exposure was made, twisted the tourniquet about the thigh tightly so that most of the dye was held in the extremity while the Bucky tray was being reloaded. The tray was then centered beneath the pelvis underlying the course of the iliac vein, and the x-ray tube was centered to correspond with the new position. The assistant removed the tourniquet from the thigh with a quick, steady movement, and the exposure was made a fraction of a second later. The first films showed outlines of the veins of the thigh and lower leg, and the second the proximal iliac veins and sometimes the lower portion of the vena cava.
Following release of the tourniquet the patient usually experienced a hot flush over the head and neck and sometimes vomited. The reaction was always fleeting.
54
The same technique was followed forphlebography of the upper extremity. The exposure wasusually made while the dye was being injected into the antecubital vein.
OtherRadiopaque Techniques
Angiocardiography was not employed at any of the vascular centers. Cerebral angiography and aortography were employed in only a few instances, the radiopaque material being injected into the aorta for the purpose of visualization of the vena cava. Fairly satisfactory results were achieved in a few instances of arteriovenous communication between that vein and the aorta.
Soft-Tissue Techniques
Roentgenologic studies by soft-tissue technique were carried out chiefly when arteriosclerosis of the peripheral blood vessels was suspected. The mere demonstration of calcification of the blood vessels by plain roentgenograms was not considered conclusive evidence of arteriosclerosis obliterans, and confirmation by special techniques was required.
The incidence of calcification of the peripheral blood vessels in young males between the ages of 30 and 40 years was remarkable. At Ashford General Hospital, for instance, between March 1944 and September 1945, 10 of the patients x-rayed for reasons other than vascular disease (or complaints referable to the vascular system) were found to have calcification of these vessels. No patients in the group had any subjective signs of vascular incapacity nor, upon intensive study, could any objective signs of either organic or vasomotor disease be discovered. Oscillometric readings, skin temperature readings, and vasomotor tests were well within the limits of normal.
It was thought significant that none of the roentgenograms of these patients showed a spotty, mottled type of calcification. The shadows in every case were smooth and uniform and gradually faded proximally into the normal portions of the vessels. These observations are in agreement with those of others who have studied calcification in a large series of unselected patients for insurance purposes. It was invariably found that subjects with the smooth type of calcification were relatively or absolutely symptom-free as compared with those who showed the mottled type of calcification.
A number of patients observed at the vascular centers with firm, noncompressible, easily palpable, cordlike peripheral arteries, who might have been expected to show roentgenologic calcification of the vessels, failed to show it. They had, however, other stigmata of generalized arteriosclerosis. They were in a higher age group than the younger men previously mentioned, and their symptoms could reasonably be attributed to cardiovascular degenerative disease. The possibility of generalized atheromatous disease, without visible evidence of calcification, suggested a form of medial sclerosis of the M?nckeberg type.
55
Teleoroentgenography
Preoperative teleoroentgenograms were made of the heart and aorta in all cases of arteriovenous fistula to serve as controls, and were usually made serially during the postoperative period in order to study changes in the dimensions of the heart after the closure of the fistula. Some degree of cardiac dilatation was usually demonstrable before operation even if the fistula had been present for as brief a period as 2 months, while the shadow was usually greatly reduced in size within a few weeks after the fistula had been closed.
MiscellaneousRoentgenographic Studies
Roentgenologic examination of parts of the body other than the extremities was sometimes carried out, usually by means of radiopaque substances, if it was thought that vascular lesions might be causing filling defects or displace ments or distortions of portions of the gastrointestinal tract, the biliary tract, or the urinary tract.
OBSERVATIONS DURING OPERATION
For several reasons, observations concerning the adequacy of the collateral circulation and the effects of temporary occlusion of the affected vessels were made during operation. In a few instances these furnished the only means of determining accurately the status of circulation in the part, the reactive hyperemia test and other preoperative studies having provided equivocal or obviously incorrect information. In the majority of cases, however, investigation during operation was supplemental to the preoperative investigation and was employed (1) to confirm the preoperative conclusion that a major blood vessel could or could not safely be occluded by ligation, suture, or endoaneurysmorrhaphy; (2) to establish the need for immediate sympathectomy or sympathetic ganglion block; and (3) to determine whether all vessels communicating with the arterial lesion had successfully been occluded by the procedure employed.
Observations were made with the artery patent and then with the artery occluded. It was desirable to occlude the vessel at a point just beyond the nearest proximal collateral branch in order to reduce the chance of occlusion of the collateral by progression of a thrombus from the blind arterial sac. Occlusion at this point provided the clearest evidence of the full potential collateral circulation and the best indication of what could be expected following permanent occlusion of the artery. Trial occlusion elsewhere left a blind segment of artery between the site of occlusion and the nearest collateral, and this segment, if of considerable length, might be responsible for sufficient absorption of pulsation to reduce the amount of blood flow through the collaterals.
Trial occlusion was carried out by digital compression or with a rubbershod clamp or a catheter. The Bethune tourniquet was also useful.
56
Inspection
When the vascular lesions or the component blood vessels were exposed, significant information was obtained. Simple inspection revealed:
1. The effects produced by prolonged direct occlusion of the involved artery (a) at the site of the vascular lesion, (b) distal to the operative field, and (c) at the proposed site of surgical obliteration.
2. The size and anatomic relationship of aneurysms and arteriovenous fistulas, with and without occlusion of the component vessels.
3. The size and relationship of the component vessels. In general, arteries proximal to an arteriovenous fistula were enlarged, but if the artery distal to the lesion was small then adequate circulation could be assumed to exist.
4. Pulseless aneurysms which occasionally were incompletely filled with blood. Aneurysms with little or no evident pulsation, suggesting obliteration of the sac with organized blood clot, were often found to be far from "dead."
5. The effect of prolonged occlusion of the involved artery on the color of a hand or foot. Color changes proved to be extremely reliable. The period of observation was often 20 to 30 minutes to allow time for full dilatation of the collateral vessels which occupies several minutes, and to allow for the appearance of whatever ischemic manifestations might occur. It had to be borne in mind, if ligation of the artery was done under spinal or general anesthesia, that the vasomotor impulses were in a state of inhibition and regardless of the observations during operation it might be necessary later to eliminate sympathetic impulses if the circulation should be compromised by vasoconstriction.
6. The adequacy of the collateral circulation as manifested by pulsation in or free flow of blood from the distal end of the involved artery during occlusion of the proximal artery. This is known as the Coenen-Henle phenomenon 13 and was the most widely used method of determining, during operation, the adequacy of the collateral circulation. The observation of a free flow of blood from the distal end of the involved artery was possible only after the aneurysm was opened, which was not done unless there was reasonable evidence of the existence of a satisfactory collateral circulation. This phenomenon indicated only that the local circulation was adequate. It did not necessarily follow that the collateral circulation was adequate throughout the entire extent of the vascular tree distal to the site of arterial involvement. It was also true that adequate collateral circulation could exist throughout the entire extent of the vascular tree distal to this site in the absence of retrograde pulsation or blood flow, the explanation being the presence of a thrombus or the existence of a cicatricial constriction of the artery distal to the point at which it was opened at operation.
13 Coenen, H.: Zur Indikationsstellung bei der Operation der Aneurysmen and bei den Gef?ssverletzungen. Zentralbl. f. Chir. 40: 1913-1916, Dee 1913. Henle, A.: Zur Indikationsstellung bei der Operation der Aneurysmen and bei den Gef?ssverletzungen. Ibid. 41: 91, Jan 1914.
57
7. The state of the intima, the possible presence of an inflammatory reaction involving all layers of the vessel wall, and the presence of arteriosclerosis or atheromatosis. This information had much to do with shaping the decision for or against restorative surgery. A final decision often could not be made until the vein and artery had been separated at the site of the fistula. The ragged appearance of the vessel sometimes made it seem impractical or actually impossible to restore the continuity of the vessel, while closer examination reversed the decision by revealing that the vessel wall was pliable and that there was little or no intimal damage. In some instances a considerable loss of substance made it seem unlikely that repair could be done without obliteration of the lumen. If, however, the arterial or venous defect was examined from the standpoint of possible transverse or oblique closure instead of longitudinal closure, a different decision might be reached.
Palpation
Palpation during operation was employed to furnish the following information:
l. Pulsation of the distal arteries following proximal occlusion. The significance of this observation has already been discussed in item 6 under the subheading immediately preceding.
2. Pulsation of an aneurysm or arteriovenous fistula before and after temporary or permanent occlusion of contributory vessels. This observation established which vessels were contributory and also established the effective ness or completeness with which obliteration of contributory vessels had been accomplished.
3. Thrill, with and without occlusion of contributory vessels.
4. Tension of aneurysmal sacs and the involved vessels or intervening sacs of arteriovenous fistula. High tension in an arteriovenous fistula indicated that the opening into the vein was small.
5. Grossly detectable temperature changes (coolness or coldness) of a hand or foot during a 20- to 30-minute or longer period on occlusion of the exposed involved segment of an artery. In observing the effect of arterial occlusion on the temperature of a part distal to the site of occlusion, it had to be kept in mind that there is a lag of variable duration in the occurrence of full dilatation of collateral vessels following occlusion of the main afferent artery to an aneurysm or arteriovenous fistula, as well as to a part which is not the site of such lesions. Instrumental determination of the temperature was used in some cases.
Auscultation
At the vascular center of DeWitt General Hospital direct auscultation with a sterile stethoscope applied over the lesion was extensively employed during operation, with and without occlusive compression of the component veins and arteries, in an investigation of bruits. The results were frequently
58
informative but were not invariablydependable for the same reason that the Coenen-Henlephenomenon could not always be relied upon. Direct stethoscopicexaminations of aneurysmalsacs were also employed before the conclusion of the operation to becertain that allcommunications had been surgically occluded, if such a result had beenintended.
Intrasaccular Inspection
In the occasional case in which the information definitely could not otherwise be obtained, it was necessary to inspect the inside of the aneurysmal sac to be sure that all vessels communicating with the sac had been identified and occluded. When occlusion of all visible communicating vessels had been achieved, either temporarily or permanently, the sac was quickly incised and bleeding points sought. Speed in opening the sac and locating possible bleeding points after occlusion of the afferent artery was essential if full advantage was to be taken of the delay in complete dilatation of the collateral vessels which follows occlusion of the afferent artery.
Temperature Determinations
At Ashford General Hospital a series of tests for circulation in the lower extremities was made in the course of operations in which the external or common iliac arteries were ligated and divided as part of the surgery for aneurysms and arteriovenous fistulas. For control purposes skin surface temperatures of the toes on both feet were recorded with the patient under spinal analgesia. Similar determinations were made at 5-minute intervals during the operative procedure, the temperature reading being correlated with the precise stage of the operation. It was thus possible to relate the temperature change to the effect of ligation and division of the iliac artery and vein. It was interesting to observe that in spite of complete anesthesia with corresponding inhibition of the sympathetic nerves, the major blood vessels reacted by spasm to manipulation, ligation, and division.
The toes of both feet were again tested after the effect of anesthesia had disappeared and followup temperature readings were made daily for 7 days. At the end of this time the temperature readings of all the toes of both feet were always equal. The patients were then subjected to vasomotor testing in a cold room. Despite the fact that the major arterial stem had been interrupted only 7 days before, the responses to temperature changes were found to be the same in all cases.
Direct Intravascular and Intrasaccular Blood Pressure Determinations
The need had long been evident for some quantitative test for adequacy of the collateral circulation which the surgeon could employ during operation when he felt some doubt about the safety of ligation of the main arterial blood supply to the extremity. Direct measurement of the blood pressure within the aneurysmal sac or distal artery was carried out in 23 cases at the vascular center
59
of DeWitt General Hospital as a means ofsupplying such information. The method proved ofparticular value when the proximity of large collateral arteries to thelesion made preoperativetests of the collateral circulation of doubtful value, or whenunsuspected collateral vessels ofconsiderable size were found communicating with the sac and had to betemporarily orpermanently occluded before the sac was opened to avoid excessivebleeding.
Since a Hamilton manometer, which would have been ideally suited for intraluminal pressure determinations, was not available, an apparatus for this purpose was devised by Maj. Norman Freeman of the vascular center of DeWitt General Hospital. It consisted of a small 3 -way stopcock fitted with short lengths of rubber tubing which connected a 20-gage needle with a 10-cc. syringe. An anaeroid manometer similar to that used with a blood pressure cuff was attached to the third outlet. The instrument, which was not itself sterile, was used in a transparent oiled silk cover which could be sterilized.
After surgical exposure ofthe lesion thecomponent vessels were encircled with heavy silkthread or rubber tubing. The needle was inserted directly into theartery or into the aneurysmalsac and a small amount (a few cubic centi meters) of physiologic salinesolution injected to clearthe system of blood. The pressure could then be read directly on thedial. Oscillations of themanometer needle, although small, indicated that the needle was withinthe blood stream. Afterthe initial pressure had been measured each of the component vesselswas temporarily occludedand variations in pressure recorded. In no instance was removal of theneedle from the artery orsac attended with bleeding of any consequence.
When this test was used one precaution was always taken: At least 2 to 3 minutes were allowed to elapse after occlusion of the main afferent artery, to permit full dilatation of the collaterals. If this was not done, grossly incorrect conclusions resulted concerning the adequacy of the circulation following major arterial ligation.
The mean initialintrasaccular pressure inthe 12 arterial aneurysms studied in this series variedbetween 110 mm. and 34 mm. of mercury and averaged 84 mm. of mercury.In the 11arteriovenous fistulas the mean initial pressure varied between 70 and30 mm. of mercury andaveraged 40 mm. of mercury. In aneurysms, constriction of the afferentartery caused a fall inthe intrasaccular pressure to an average of 58 mm. of mercury, while infistulas a similarprocedure caused an average fall of 10 mm. of mercury. It was foundthat with a pressure of 32 mm. of mercury tissuesurvival could be expected. This is in accord withKorotkow's observation that a pressure of 30 mm. of mercury is adequate.
