Medical Science Publication No. 4, Volume 1
THERMAL BURNS*
LIEUTENANT COLONELEDWIN J. PULASKI, MC
With every war the menace of thermal injuries seems to be increasing.The expanded use of gasoline in transportation of supplies and troops onthe ground and in the air, the use of napalm and high explosives both formilitary operations and the destruction of cities, culminating in the nuclearfission weapons with their prospect of thousands of burns casualties-allthese compel us to ask what has been learned from Korea, and what, if anything,could be done in the event of another outbreak of hostilities to improvethe care of burns casualties.
In the past, the standard of treatment of burned patients in both civilianand military hospitals has often been poor, usually because, compared tomany other emergencies, the management of such patients is more difficult.Few hospitals receive sufficient numbers of patients to attract and maintainthe interest of the senior surgeons, or to keep the standard of treatmentat a high level. More often than not, the care of the occasional burn injurypatient admitted to the general surgical service of a hospital becomesthe responsibility of a junior member of the staff. After costly delayin terms of healing time, chronic anemia, avitaminosis and secondary infection,the patient is then transferred to another hospital for plastic surgery,before or after previous trials of skin grafting.
In 1948 the Surgical Research Unit located at Fort Sam Houston, Texas,established a burns study program as its major activity. The immediatereturns from the program at the Surgical Research Unit included revisionof the Berkow scale for estimating the extent of the burn to the "Ruleof Nines" formula, recognition of the Brown Electrodermatome as asimple, rapid, efficient means of cutting skin for grafting, demonstrationof untoward reactions following infusions of Swedish dextran in human volunteers,and definition of the potentialities of the exposure principle of localcare of burns.
The opportunity was afforded Major Artz and me in November 1950, toextend these observations and make others on Korean burns casualties atTokyo Army Hospital, where special facilities were provided.
*Presented 21 April 1954 to the Course on Recent Advances in Medicine and Surgery, Army Medical Service Graduate School, Walter Reed Army Medical Center, Washington, D. C.
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One estimate is that thermal injuries constituted 2 percent of casualtiesin Korea admitted to hospitals. This is attested by the fact that in the3 months of our stay, over 100 such casualties were admitted to Tokyo ArmyHospital. In the overwhelming majority of instances (80 percent) the burnswere accidentally incurred and were, therefore, preventable. There wasno organized program for the care of burns casualties, for which reasonthe Unit was set up in Tokyo. Later another unit was established on theGeneral Surgical Service, Osaka Army Hospital.
Principles of Treatment
1. Early, Accurate Diagnosis. It should be realized that anyextensive deep thermal burn is a complex specialized problem. A brief historyof previous illness, and a careful history of the details of the accidentare essential. The latter may give clues as to the depth of the burn andthe degree of the emergency which it presents. The minimum of informationshould include: (1) the possibility of respiratory tract burn; (2) thelocation, extent and estimated degree of surface burns, with a quick sketchof the burned area; (3) notation and assessment of associated injuries,and (4) a record of the agent causing the burn (fire, flash, chemicals,steam, electricity). Accurate diagnosis of the depth of the burn is notalways possible on first inspection. A common tendency, even for the experiencedobserver, is to underestimate depth.* But the importance of diagnosingcorrectly burn depth lies in the fact that only thus can the magnitudeof the problems facing the patient be appreciated.
2. Diagnosis of Extent. The "rule of nines" is a convenientmeasure. Each arm is 9 percent of body surface, the head is 9 percent,front of trunk 18 percent, back of trunk 18 percent, each leg 18 percent,and perineum 1 percent. The importance of correct estimate of extent liesin the fact that treatment will be partly guided by extent of the burn,and prognosis likewise.
3. Triage of Burns Patients. The risk of burns increases withthe age of the patient and the body area burned. In general, the effectsof burning are lethal in patients over 50 years of age with deep burnsover 50 percent of the body surface. This trend has been expressed
*It seems preferable to classify depth in terms of partial thickness and full thickness. Partial thickness connotes first and second degree burns. A first degree burn, like a sunburn, is manifested by erythema and edema, small blisters and superficial desquamation, or the formation of serous bullae, under which is the familiar red, tender, painful, exudative skin. An obvious full-thickness burn can present as a firm, black or dark brown leathery eschar or a cold white marble or gray appearance with or without heavy desquamation and underlying pale pink or white dermis, or the presence of a network of thrombosed vessels within the corium. Such a burn is usually anesthetic to pinprick. It represents destruction of all epithelial elements and leads to separation of the eschar to an open granulating wound.
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in a chart of mortality probabilities for different combinations ofages and body area burned prepared by the Birmingham Burns Unit-the mortalityis shown as a decimal of 1.0. Zero denotes less than 5 percent chance ofdying and 1.0 denotes a greater than 95 percent chance. For example, ayoung adult with a 50 percent burn has a 50 percent chance of dying.
From the foregoing a preliminary classification of the burn patientcan be made:
1. Hopelessly burned (deep burns exceeding 70 percent of body surface).
2. Emergency cases.
a. Acute or impending respiratory emergency at the time of admission.
b. Chemical burns and ocular burns.
c. Extensive burns with concomitant visceral injuries, lacerationswith profuse continuing hemorrhage, or compound fractures.
d. Patients with burns involving 15 to 70 percent of the bodysurface, who can be saved by vigorous therapy.
3. Patients with major burns in no immediate danger but requiring formalinstitutional care: partial-thickness burns of 10 to 15 percent of bodysurface, and full-thickness burns over 1 to 15 percent of body surface.
4. Patients for ambulatory treatment: burns less extensive than above,with no respiratory or ocular injury.
Plan of Treatment
A major cause of death after thermal injury is shock, and infectionis the second most common cause. Scarring is the chief cause of deformityand disability. All these complications are easier to prevent than to cure.Shock may be prevented by early and adequate restoration of the fluid lostfrom the circulation. Clinical infection may be prevented by protectionof the burn against colonization by bacteria by immobilization and by earlygrafting. Contractures and fibrosis may be prevented by early elevation,prevention of infection, correct positioning of the patient, and earlydébridement and grafting.
Immediate (Emergency) Treatment. Prevention of the complicationsof burning begins with support of blood volume, appropriate sedation, dressingand transportation to experienced hands. After noting the extent and severityof the burn, the clothing is examined for possible smoldering, which, ifdetected, is extinguished by dousing with water. Otherwise, it is probablybetter that the clothes be left
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undisturbed until the patient reaches the hospital, and that the burnsurface be covered with a clean sheet or towels held in place with a bandage.No local medications of any sort are applied. If the burn involves theface or perineum, it is left exposed. The only indications for immediatetreatment of the local wound are the chemical burn, for which antidotesare applied if available, and the corneal burn, for which a protectivedressing is applied over the eye.
Sedation is best effected with barbiturates given intramuscularly. Theamount of morphine, if administered at all, should not exceed 15 mg. intramuscularlyin the first 4 hours, and it is contraindicated in the patient with acuteor impending respiratory emergency. Most burns greater than 10 percentof body surface will require intravenous fluid replacement therapy. Ifthese are available at the emergency station, an infusion is started, withwhatever fluid is at hand. Albumin, plasma volume expander, dextrose insaline, saline, or dextrose in water may be used, in that order of preference.The fluid administered should be correctly recorded. The patient is evacuatedas soon as possible to a hospital.
Therapy in the Hospital. As a burned patient is first seen, thepresence of established respiratory emergency is diagnosed by rapid respirationsand cyanosis. Crowing noises, gasping, frothing, coughing, or hoarsenessmay or may not be present. Pulmonary signs of ronchi, rales or atelectasisare also variable. In the presence of any or all of these, tracheotomyshould be considered. In the presence of cyanosis, it should be done atonce. If there is a burn of the face along with any warning signs of respiratoryinjury, it is well to remember that burn edema soon to follow will maketracheotomy difficult and it should be done at once. Although severe respiratorytract injury may be below the trachea, the tracheotomy facilitates bronchialsuction and direct oxygen insufflation. Oversedation with depression ofrespiration and cough reflex must be avoided. Fluid therapy must be administeredwith caution because of the tendency to pulmonary edema.
When respiratory emergency does not threaten, the patient's clothingis removed, the extent of the burn is mapped out according to the "ruleof 9's," an estimate is made of the patient's weight (most patientscan tell their weight with accuracy), an indwelling plastic tube or needleis inserted under local anesthesia into an accessible vein, and a bloodsample is obtained for hemoglobin and hematocrit determination as wellas for typing and cross-matching, and finally, an indwelling Foley-typecatheter is placed in the bladder for hourly measurement of urine volumeand detection of renal damage as evidenced by albumin, casts and hemoglobin.The extent of the surface area
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burned is a guide to planning the amount and kind of fluids needed.Renal output is the best guide by which to modify this plan.
There is general agreement that the main cause of burns shock is oligemia,chiefly due to loss of plasma. To the external loss into blisters and fromopen surfaces is added the edema of tissues deep to and surrounding thosedestroyed. Unlike patients with other forms of traumatic shock, in theburn patient fluid loss and threatened shock continue over a period of24 to 36 hours. The aim of fluid replacement is to keep pace with thisloss with a minimum of other disturbance. In addition, red blood cellsare directly destroyed in a burn sufficiently deep to coagulate the dermalcapillaries. There is also a delayed hemoglobinemia which may be due, eitherto intravascular hemolysis of cells not completely destroyed but renderedmore fragile by some process, or to a hemolytic factor produced at thesite of injury. In an extensive burn the blood loss in the initial phaseamounts to 8 to 10 percent of the blood volume. The plasma loss approximates0.5 to 1.0 cc. per kilogram of body weight for each 1 percent of body surfacearea burned. The loss of water and electrolytes into the burn, coupledwith insensible and renal loss, approximates double or more the plasmaloss. Unless these fluids are replaced, death from cell damage due to dehydrationor tissue anoxia may supervene. If replacement is continuously accomplished,the continuing tendency toward shock will be avoided or relieved.
The treatment of burns shock is its prevention. This requires recognitionof the cases which will develop shock, and the best guide is the extentof the burn as measured in percentage of the body area. Patients with lessthan 10 percent of body surface burned ordinarily will not require intravenoustherapy. In these supplemental fluids by mouth may be given in the formof a solution containing 3.5 gm. of salt and 1.5 gm. of bicarbonate ofsoda dissolved in a quart of water, and chilled and flavored to taste.In more extensive burns, the following simple formula may be used as astarting guide to fluid replacement therapy, subject to extension upwardsfor children, and downwards for the elderly patient, the presence of pulmonaryinjury, and the involvement of more than 50 percent of the body surface.
Percent body surface burned X weight in kg. X 0.5 to 1.0 = ml. of colloidneeded in 24 hours. The use of plasma carries with it the risk of jaundice.This risk makes it desirable to examine alternatives to plasma in the treatmentof burns. Whole blood, albumin and dextran are suitable. Electrolytes and5 percent dextrose in water should be administered in amounts sufficientto maintain a urinary output of no less than 30 ml. per hour. If wholeblood or albumin are not used, it is wise to administer a liter of 1/6Molar lactate to correct acidosis as part of the electrolyte replacement.For example, the fluid re-
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quirements in the first 24 hours for a 70 kg. man with a 30 percentburn can be illustrated as follows:
Whole blood, or plasma volume expander | 0.5 X 30 X 70 = 1050 ml. |
Electrolyte solutions | 1.5 X 30 X 70 = 3150 ml. |
5 percent dextrose in water | 2000 ml. |
| Total | 6200 ml. |
These fluids are rationed so that one-fourth of the total amount isgiven in the first 6 hours after burning, the second one-fourth in thenext 6 hours, and the remainder in the final 12 of the 24 hours. Oral fluidintake should be included in this calculation. It is reiterated that acommon error is to overestimate the extent of the burn and to be overzealousin fluid replacement. If the urinary output exceeds 30 ml. per hour butnot 60 ml., the amount and rate of fluid administration can be consideredadequate. When the urinary output falls below this minimum, a test of theadequacy of fluid intake is the rapid intravenous administration of 500ml. of 5 percent dextrose in water; if prompt diuresis follows, the fluidintake is cautiously increased.
Half the amount of fluid required in the first 24 hours is adequateto maintain the patient during the second 24 hours. Close observation ofthe urinary output and of the hematocrit will reveal exceptions, and thefluid ration should be altered as necessary. During the third 24 hours,spontaneous diuresis should be watched for and the fluid intake shouldbe gauged accordingly. In general, oral and intravenous electrolyte therapyis not required after the first 48 hours. After the fourth day, the patientbeing stabilized, the urinary catheter should be removed.
Treatment of shock must be conditioned by simultaneous treatment ofthe injury under the following circumstances: (1) Chemical burns, whichmust be treated concurrently; (2) respiratory burns; (3) burns with extensivevisceral injuries, lacerations with profuse hemorrhage and complicatingfractures may require simultaneous treatment of these complications andthe shock.
The local treatment of partial- and full-thickness burns is based onthe triad of nursing care, resistance of the patient and rest of the affectedpart. By resistance of the patient, is implied avoidance of anything whichmight interfere with the reparative processes of the body. This means effortsare directed toward production and maintenance of a wound environment unfavorableto the growth of bacteria and favorable to wound healing. If the woundis grossly dirty, an effort is made to make it cosmetically clean withoutproducing undue additional trauma. This is accomplished by general cleansingwith a detergent and warm water, and débridement of loose tags ofskin and blisters. Intravenous morphine analgesia usually is suffi-
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cient for this purpose. Following cleansing, the whole area is carefullydried by soft towels. No local antiseptics or antibiotics are employed.The resistance of the patient is best aided by obtaining and maintainingan early dry surface which is kept cool. A moist warm exudate is a suitablebacterial pabulum favorable to the rapid colonization of the burns surfacewith microorganisms; conversely, a dry cool surface is less favorable forbacterial growth.
The dry surface, once effected, consists of a coating of fibrin, which,in the partial-thickness burn, then acts as a matrix for the ingress andcoalescence of epithelium from the depths and margins of the wound. Inthe full-thickness burn it seals off the wound from invading bacteria andprovides optimal conditions for the demarcation and separation of the burneschar. Fibrin deposition is aided by rest and immobilization, and elevationto limit edema, whenever practicable. Once fibrin formation has been completed,the burn is no longer painful unless it becomes infected.
At present, there are two principal methods of bringing about a drywound surface: the open or "exposure" method, and the absorptiveor occlusive dressings method. In connection with the latter, it shouldbe noted that the word "pressure" has been left out. The importanceof absorptive dressings has often been erroneously attributed to theirability to prevent or minimize, by compression, the leakage of plasma fromthe burn surface by a dressing which does not need changing for approximately10 days. Therefore, absorptive dressings should be sufficiently bulky toserve their purpose, so that fluid is blotted up and fibrin depositioneffected. The "open" or "exposure" method results ina dry fibrin-covered surface. Formation of this coagulum is hastened byimmobilization and a cool, dry environment, and is retarded by motion andthe abrasive action of linens, etc. Once the crust has formed, which takesabout 36 hours, the term open or exposure no longer applies. As epithelizationtakes place, the crust separates and can be lifted or cut away. Partial-thicknessburns so treated heal in 12 to 24 days, depending on their depth and location.
A large burn dressing developed by the National Research Council isbest used on encircling burns of the trunk and extremities and burns withcomplicating mechanical injuries. Burns of the hands require a smallertype of dressing which will permit elevation and splinting of the partin the position of function. A simple sterile covering is employed forminor burns of limited configuration. If such materials are unavailable,or in short supply, burns of moderate extent may be covered with clean,dry, freshly laundered or sterilized linen or toweling loosely kept inplace by a bandage.
The principal indications for the open method are: uncomplicated burnsof the face and the perineum and profile burns so located that
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positioning will permit free access to the circulating air and recumbencyof the patient on the unaffected side. Partial-thickness unilateral burnsof the hand have also been successfully treated by the open method; however,full cooperation of the patient is required to maintain elevation and theposition of function while the eschar forms. A combination of absorptivedressings and exposure has been employed in circumferential burns, suchas those of the trunk and the thighs. This method carries with it the riskof suppuration in the areas which cannot be immobilized, where fibrin depositionis inhibited. In a disaster the closed method should preferably be usedfor all burns where complete eschar formation is unlikely to result followingexposure.
The indications for the change of dressings may be categorized as eitherimmediate or late. The immediate indications include: (1) excessive pressureas a result of faulty application or excessive edema formation, (2) soakingthrough of the dressings, (3) slipping, and (4) unexplained fever or pain.If none of these occur, the dressing is left in place for 7 to 14 days.At this time reassessment of the burn makes possible clearer definitionof partial- or full-thickness involvement. If the burn is partial thicknessin its entirety, it is redressed and removed after the fourteenth day,by which time re-epithelization should be nearly complete. If there areareas of full-thickness involvement, plans are made for skin grafting.
The defenses against infection are abetted in severe burns by prophylacticantibiotic therapy. Systemic penicillin or other antibiotic is given parenterallyfor about 5 days. In the severely burned patient, the initial dose is givenin the intravenous infusion. The use of oral antibiotics early is inadvisablebecause of vomiting. Standard doses of tetanus antitoxin, tetanus toxoid,or both, are indicated. The prophylactic use of polyvalent gas gangreneantitoxin is not recommended. The use of ACTH or cortisone is also notrecommended since recent observations indicate that fulminating spreadof infection may attend their administration and, further, that their administrationdoes not diminish the need of the burned patient for blood, colloid, electrolyteor water therapy.
By the end of 5 days the microorganisms colonizing a burn are likelyto be drug-resistant. The concept of stopping antibiotics, waiting a fewdays depending on circumstances, and then reinstituting them, using a differentdrug or combination of drugs, has been practical and fruitful, particularlywhere the change of antibiotics may directly precede grafting. During theperiod of eschar separation the burn wound becomes increasingly painfulas new nerve endings in the subcutaneous tissues become active receptors;this pain is aggravated by the presence of infection, motion or contact,until wound
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closure has been secured. Dressings should be done under anesthesia,in the operating room. The golden moment is the time at which débridementcan be done safely and at which skin grafts can be placed. The conceptthat a burned area must show "healthy" granulations in orderto be "ready" for a graft is erroneous and invalid. In the burnedpatient the wound is ready for grafting when the eschar permits easy removaland clinical manifestations of infection are absent. In most burns theseconditions coexist sometime after the second week.
Nutritional Care. After a severe burn the nutritional state isprofoundly affected. The metabolic rate rises rapidly and may remain elevatedfor several weeks. The "reaction to injury" occasions an increasedloss of nitrogen in the urine and this loss is greatest in previously healthyadults. Nitrogen is also lost from the burned surface, particularly inextensive infected burns. Lastly, demands for protein are increased bythe processes of repair and healing.
At present, exact requirements for the various nutritional elementsare not fully defined. From the third day of injury a planned increasein oral intake should be instituted until the patient's fluid intake isestablished at the desired level. Immediately after burning, patients withsevere burns reject food or have poor appetite. Fluid feedings with orwithout nasogastric intubation are usually indicated. Gavage feeding insuresa measured caloric intake. Various formulae which provide a balanced foodintake with an adequate number of calories are available for this purpose.An optimal intake is 3,500 calories, 450 gm. of carbohydrate and 250 gm.protein. Vitamins should be given parenterally with emphasis on vitaminC (up to 1,000 mg. a day). Blood transfusions to correct anemia are givenas indicated. Tube feeding is continued until the patient's appetite isfully restored. Early muscle movement will increase the proportion of nitrogenretained from the diet and limit the process of bone decalcification.
Skin Grafting
The closure of the full-thickness burn by skin grafting should be initiatedas soon as practicable. Surgical excision of the eschar is feasible whenthe area involved does not exceed 5 to 8 percent of the body surface andthe risk of shock is not great. Other methods of management of the eschar,such as enzymatic débridement, are now under investigation.
The cutting of the graft is best effected by the use of some form ofdermatome. The electrodermatome is especially suited for the casual operatorbecause it will remove thin grafts, will not damage donor sites, takesgrafts swiftly, and requires very little experience to insure
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proficiency. The grafts required are of intermediate thickness, 10 to15 thousandths of an inch. Such grafts take in the presence of a mild infection,except when the wound is colonized with hemolytic Streptococci. Intermediate-thicknessgrafts also leave better donor sites, which can be used for a second cropof skin after 21 days. It is recommended that skin in excess of the amountrequired to surface the burn be taken and stored in bottles containing10 percent human serum or in gauze moistened with saline solution. Thesebottles are stored in the ice box at 5° to 8° C. Such grafts canbe used up to 4 weeks after cutting. Antibiotics are given 48 hours beforeand after operation as a precaution against spread of infection. The agentchosen should be on the basis of culture sensitivity tests of the woundexudate.
Grafts are maintained for 48 hours by the plasma circulation. Thereafter,ingress of capillaries begins and is complete in 5 to 10 days, dependingon the body site and the thickness of the graft.
If the graft was applied to a clean area, the dressings are left aloneduring this period, that is, usually for 7 days or longer. If they wereapplied in the presence of suppuration, dressings are changed after 48to 72 hours, using extreme care not to dislodge the graft. The wound isgently cleansed and carefully redressed, using the strictest aseptic precautions.Nonadherent grafts and overlapping tags of skin are trimmed away at thetime of the first dressing.
The burned patient who is treated well can usually leave the hospitalin 3 weeks to 3 months, depending upon the extent and depth of the injury.If the patient has not been treated well by failure to institute efficientsystemic treatment, failure to prevent infection, or failure to institutegrafting procedures at the right time, one is confronted with the viciouscycle of anemia, infection and malnutrition, which prolong the treatmentfor months, increase disability and deformity, and enhance the drain onhospital time and personnel. Patient morale is badly shaken, for whichfrequent, painful and exhausting dressings and despondency over failureto make progress are contributing factors. Such patients require repeatedtransfusions, usually twice a week until skin cover has been provided.Efforts to correct hypoproteinemia must be vigorous. Combined parenteraland oral alimentation will be necessary. Control of infection is initiatedin the operating room where a total body cleansing is given to the anesthetizedsubject, with liberal use of a detergent and water. Débridementis indicated if dead tissue remains. Body defenses are aided by the useof antibiotics topically and parenterally, based on culture sensitivitytests. Septicemia is a threat in these patients until complete skin coveragehas been attained.
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Plan for Treatment of Burns Casualties in a Major Disaster. Theresults of the experiment of setting up a Burns Treatment Center at BrookeArmy Hospital and at Tokyo Army Hospital during the Korean action havebeen amply rewarding. It has been demonstrated beyond doubt that, providedpatients are seen early after injury and a high standard of surgical andnursing care is given in suitable facilities, disability and complicationscan be prevented. In the event of another war, as a basis for discussion,the following suggestions are put forth:
1. A plan should be executed to provide a short training for a largenumber of doctors, nurses and corpsmen in the modern treatment of burns.This training should be started at once in the Army center now available,and should be extended as soon as other centers are organized. Surgeonsshould be taught the essential principles of preventive treatment of shockand infection, and simple technics of débridement and skin grafting.This force of partly trained personnel would form the nucleus in an emergencyto direct others not so trained who would need to be recruited on the spot.
2. Establishment of Burns Specialty Centers in the theater of operations.Such a facility should have a sufficient number of beds to carry out itsmission, but no more than 40 in one center. An adequate staff for 24-hourduty is essential if supervised shock treatment is to be carried out, aswell as routine dressings and other ward work. The unit should have itsown operating facilities, preferably one room for septic cases and oneroom for the care of clean cases.
An adequate shock room is necessary, preferably several individual rooms,which, when the incidence of burns is small, could be converted to isolationrooms. Efforts to combat infection during dressings changes envision theneed for an operating room or its equivalent for older cases and anotherroom for recent, presumably clean cases.
The treatment of burns is the responsibility of a team and not any oneindividual. It is full of problems which can be faced only by adequatestaffing. The Brooke Center experience points to the wisdom of appointingan anesthetist, internist, psychiatrist, dietitian, bacteriologist, biochemistand physical therapist to work alongside the surgeon. Full recognitionof the emergency nature of the treatment of burns and of the problems ofthe treatment of shock, control of fluid and electrolyte imbalance, nutrition,anemia, sepsis and psychiatric disturbances, will be sufficient to makea plea for a Burns Center so staffed justifiable.
