Part at One General Aspects of Surgical Care
A Survey of Evacuation, Resuscitation, and Mortality in a Forward Surgical Hospital*
Captain Yoshio Sako, MC, USAR
Lieutenant Colonel Curtis P. Artz, MC, USA
Captain John M. Howard, MC, USAR
Captain Alvin W. Bronwell, MC, USAR
Captain Frank K. Inui, MC
Although more effective weapons have been devised with each succeeding war, the case fatality rate of the wounded soldier has steadily declined. An evaluation of the methods of treatment of the battle casualty requires accurate and complete recording of data concerning patient care, complications, and case fatality rate. These data may then be compared with data obtained from similar groups in previous wars. The dissemination of such information is a very important factor in the continued improvement in the treatment of battle casualties.
This report covers the period from January 1, 1952, to August 1, 1953,** of the Korean conflict, during which time the Surgical Research Team was active in studying various problems at the 46th Surgical Hospital (Mobile Army). This hospital was located approximately 10 miles behind the battle lines on the eastern front. The building was of tropical-shell construction and had a concrete floor. The hospital was equipped and staffed to do all types of major surgical procedures.
During the period covered by this report, large numbers of projects were being carried on and, as various ones were completed, others were initiated. In some instances, new projects were begun when there was a change in personnel. One of the last projects to be initiated was the survey of evacuation, resuscitation, complications, and mortality on every casualty admitted to the general surgical service.
Section I. Evacuation and Resuscitation of Casualties During the Final Three Months of the Korean Conflict
In this particular survey, the period covered was from May 1, 1953, to August 1, 1953. Although this represents a relatively short period
*Previously published in Surgery 37: 602, 1955.
**Records were lost for the month of January 1953.
of time, some of the information gathered appears to reflect experiences gained in the previous 15 months. The survey was made when there was little change in the tactical situation, patient load, mode of evacuation, and when there was no change in the site of the hospital.
Study sheets covering statistical data were completed for all general surgical patients. These sheets were made an integral part of the patient`s record while he was in the hospital; and they were removed only after the patient was evacuated to the rear or discharged to return to duty. The admitting officer completed all pertinent administrative data, and additional information on the patient`s care from injury to discharge from the hospital was completed by the medical officer assigned to the particular patient. The statistical-data sheets were tabulated each month, and the staff utilized this information in discussions. Patients included in the survey were those sustaining wounds of the abdomen, chest, or combined wounds of the chest and abdomen, those requiring amputation, and those having open fractures.
Table 1 shows the total number of casualties and the mode of evacuation. There were 250 patients in this group; 75 had abdominal wounds, 29 thoraco-abdominal wounds, and 33 thoracic wounds. There were 31 patients who required amputations; and 82 sustained open fractures. Except for the group sustaining open fractures approximately one-half of this group was evacuated by helicopter.
Table 1. Case Fatality Rates and Mode of Evacuation
Table 2 shows the average time interval for various phases of care. In the five groups, the average period from injury to admission was 3.6hours, and from injury to surgery 6.6 hours. The operative procedure averaged 1.8 hours. The length of the operation for casualties with abdominal and thoraco-abdominal wounds was greater than for casualties with other types of wounds.
Table 2. Time Intervals
Table 3 lists the average amount of blood administered to the various types of casualties. Several in this group received 1 unit of dextran or albumin prior to admission; whereas only a few received blood prior to admission. All but the open fracture group were given an average of 2 liters of blood preoperatively. During operation, patients received an average of more than 2 liters of blood, except in the casualties sustaining chest wounds and those having open fractures.
In the first 24 hours following injury, patients having abdominal wounds and those requiring amputations were given an average of 3.5 liters of blood. Patients having thoraco-abdominal wounds, thoracic wounds, and open fractures, received an average of 2.9, 1.9, and 0.9 liters of blood respectively in the first 24-hour period.
Table 3. Blood Transfusions
Deaths and Case Fatality Rates
Table 4 lists the deaths and the case fatality rates for each group. There were nine deaths in the group having abdominal injuries, a case fatality rate of 12 percent. Of this number, five patients died of uncontrolled hemorrhage, two of peritonitis, and one each of aspiration pneumonia and pancreatitis. There were three deaths in the thoraco-abdominal group, a case fatality rate of 10.3 percent. The causes of death were uncontrolled hemorrhage, postoperative shock, and cardiac arrest. There were two deaths among patients suffering from thoracic wounds, a case fatality rate of 6.1 percent. One patient died of a massive, uncontrolled hemorrhage from a lacerated pulmonary vein; and one patient died of air embolism which occurred during positive pressure transfusion. There were three deaths in patients suffering from traumatic amputations, a case fatality rate of 9.7 percent. One patient died of uncontrolled hemorrhage, one of cardiac arrest following excessive morphine, and one of massive hemorrhage from the thigh immediately after admission to the hospital. In the open fracture group there was only one death, an incidence of 1.2 percent. This patient died of uncontrolled hemorrhage from massive wounds of both upper thighs. He was given 12 pints of blood in 30 minutes, but failed to respond. In the casualties described above, more than half of the deaths were caused by uncontrolled hemorrhage.
Table 4. Causes of Death
SECTION II. Case Fatality Rates in 1952 and 1953
Data on total admissions were obtained for the period from January 1, 1952, to January 1, 1953. During this time, 3,716 general surgical patients were admitted to the 46th Surgical Hospital; and 83 of these died making a case fatality rate of 2.2 percent. During the period from February 1, 1953, to August 1, 1953, 995 general surgical patients were admitted to the hospital; and the case fatality rate for these patients was 3.2 percent. During the two periods mentioned, various types of patients were admitted. In 1952,all but a few casualties requiring operations were admitted to the hospital. In 1953, many of the less severely wounded soldiers were operated on at a clearing station. Over-all case fatality rate for these two periods was 2.4 percent.
From January 1, 1952, to January 1, 1953, 327 patients were admitted to the hospital who had abdominal injuries; and 42 deaths occurred in the group, a case fatality of 12.8 percent. From May 1 to August 1, 1953, 9 deaths occurred among the 75 casualties sustaining abdominal wounds, a case fatality rate of 12 percent. The combined case fatality rate for these two groups was 12.6 percent.
From January 23, 1952, to October 1952, and from February 1, 1953, to August 1, 1953, there were 140 casualties who required major amputations (Table 5). Of this number, 11 deaths occurred, a case fatality rate of 7.8 percent. Table 5 shows the distribution of the levels of amputation and the number of deaths in each category.
Table 5. Major Amputations*
Section III. Comparison of Experiences in Korea with a Similar Group in World War II
It is difficult to make an accurate comparison of mortality statistics of any two wars, or even of various groups in the same war, because of the many factors contributing to the mortality in the wounded. Forsee stated that no sizable group of American military surgeons ever had such a vast experience in the surgical care of the severely wounded as did the Second Auxiliary Surgical Group in World War II.1 This group worked in the first priority surgical hospitals whose location and function in the chain of evacuation was similar to that of a Mobile Army Surgical Hospital in Korea. For this reason, the findings of the Second Auxiliary Surgical Group were a comparable basis for evaluation of the statistical data gathered in Korea.
Table 6 shows a comparison between World War II and Korea of time intervals for evacuation of casualties with abdominal wounds. The time interval from injury to admission to the surgical hospital was shorter during the Korean conflict; but the interval from admission to surgery was not greatly changed. Usually, the interval from injury to admission was approximately twice as long during World War II as it was in Korea.
Table 6. Comparison of Time Intervals in Casualties with Abdominal Wounds
Comparative data on resuscitative fluid is difficult to obtain for World War II. Table 7 shows the report of the Second Auxiliary Surgical Group on the use of blood and plasma administered to casualties who had colon and rectal wounds. This report mentioned that rarely was there any limit to the supply of blood and plasma. No time interval was stated for periods during which blood was given;
however, it is assumed that the interval includes all periods during which blood and plasma were given while a casualty was at the First Priority Hospital. The total amount of blood given to the casualties who survived approximated 2 liters of resuscitative fluids per patient. The casualties who died had received approximately 3.5 liters, while the average for both groups was 2.5 liters.
Table 7. Blood and Plasma Transfusions in Casualties with Colon and Rectal Injuries, World War II*
In World War II, casualties who had colon and rectal wounds received an average of about 1 liter less of resuscitative fluids than did the casualties who sustained abdominal wounds in the Korean conflict (Table 3).
Comparison of Case Fatality Rates
It is difficult to make an accurate comparison of case fatality rates for World War II and for those reported in this survey, because no comparable groups are reported. In the Mediterranean theater of operations from January to June 1944, the case fatality rate of 34,731 casualties was 3.3 percent.2 This group excluded those injured soldiers who were returned to duty from the battalion aid stations, clearing stations, and dispensaries. In this 18-month survey of the Korean conflict, the over-all case fatality rate was 2.4 percent for the general surgical patients at the 46th Surgical Hospital.
Our study shows that among those who had abdominal injuries, the organ most frequently involved was the colon (Table 8). Second in frequency were injuries of the small intestine and liver. The next most commonly injured organs were the kidney, spleen, and stomach, in that order. Incidence of organ injury followed in order rather closely the figures compiled for World War II. During our series, the case fatality rates of all groups were consistently lower than in the World War II series; and, in many instances, the rate was approximately half that of World War II. An exception in our study was injury to duodenum; 17 patients had duodenal injuries, a case fatality
rate of 43.1 percent. Our survey indicated a high rate of mortality in patients1 with ureteral injuries. In four such patients, the case fatality rate was 50 percent; whereas, among 27 cases of ureteral injuries in the World War II series, it was 41 percent.
Table 8. Comparative Statistics for Case Fatality Rates of Abdominal Wounds by Organs injured -- Korea,1952-1953, and World War II, 1942-1945*
To equalize the time interval from injury to admission, the series covering the Korean conflict was grouped according to the number of organs injured in those casualties who were operated on within seven hours following injury (Table 9). This method was adopted in order to compare results with a similar group of casualties in World War II on which tabulation was made by Beebe and De Bakey. In their series of 1,185 casualties with abdominal wounds, the case fatality rate was 21 percent; whereas, in the 384 casualties reported here, it was 11.9 percent.2 In the World War II series, the casualties included those who were operated upon within 7 hours following injury; whereas, in the Korean conflict series, the casualties included those operated upon within an average of 7 hours after injury. Consequently, in the latter group, many casualties were undoubtedly operated on at a time which exceeded 7 hours after injury. Since the time element was essentially comparable, the lower case fatality rate in the Korean conflict series cannot be ascribed entirely to the shorter period of evacuation.
Comparison of data on thoraco-abdominal wounds again revealed that the case fatality rate according to organ injured in our series
Table 9. Comparative Statistics for Case Fatality Rates for Abdominal Wounds by Number of Organs Injured
Table 10. Case Fatality Rates of Thoraco-abdominal Wounds by Organs Injured
was approximately half of that in the group studied by Beebe and DeBakey (Table 10). The greatest difference occurred in those casualties sustaining gastric wounds. In our study, 23 patients having gastric injuries had a case fatality rate of 4.3 percent as compared with the World War II series in which there were 93 deaths among 211 casualties (44 percent).
Further analysis of the thoraco-abdominal injury groups was made in terms of the side of the chest involved. In our series, 72 of the 129 thoraco-abdominal injuries were primarily on the right side and 57 on the left, with a case fatality rate of 16.6 and 8.7 per cent respectively (Table 11). In the World War II series, of 883 thoraco-abdominal injuries, the number was approximately equal on the right and left sides (435 on the right side, and 448 on the left). The case fatality rates in the latter series were approximately the same for both sides (24 percent for the right and 30 percent for the left).
One of the important determining factors in the causation of death depends upon the body region which is injured and more particularly, the tissue involved. The study by Beebe and De Bakey of casualties in the Mediterranean Theater showed that, among the 36,000 wounded soldiers who had lost time because of injury during the first six months of 1944, the case fatality rate was higher in those suffering from abdominal injuries (17.4 percent). Chest wounds stood second to abdominal wounds in case fatality rate (8.1 percent), and head, face, and neck wounds were 5.7 percent; the lower extremities, 2.1 percent; and the upper extremities, 1.1 percent.2
For a number of reasons, a missile wound of the chest, abdomen, buttocks, and upper thigh which was equally extensive, would probably have a decreasing mortality in the order listed. In all probability, an extensive wound of the chest would prove fatal in a very short time following injury; whereas, an equally large wound of the abdomen would probably injure multiple organs and bring about an equally high case fatality rate (see Table 9). In the regions of the buttocks and thigh, a wound would probably bring about a case fatality rate directly proportionate to the ease or difficulty of hemorrhage control.
When comparing regions of the body involved with case. fatality rate, there appears to be a differential in the rates which have been unchanged during the different wars, even though the over-all rate has decreased. Case fatality rate may be related to blood loss because of injuries involving various regions of the body. However, it may be more closely related to the ease with which control of blood loss is brought about. For example, a simple laceration of an artery in the thigh is easier to control than in a wound where there is multiple extensive, soft-tissue damage in the same area.
In some areas of the body, a higher incidence of complications may be expected due to peculiarities of the specific region. In the abdomen, aside from blood loss, there is the grave complication of infection of the peritoneal cavity secondary to perforation of the gastro-
Table 11. Comparative Case Fatality Rates for Thoraco-abdominal Wounds
intestinal tract. In the case of muscle wounds of the thighs and buttocks, there is the ever-present danger of myositis. In chest wounds, the location of the vital organs and of major vessels and pulmonary function which maybe complicated postoperatively, contribute to a higher case fatality rate for injuries in this area.
Each war presents a different set of circumstances, and this may reflect upon case fatality rates. Rates would be higher in a fast-moving war where casualty loads would be heavy. An increased mortality rate would be reflected in this instance due to compromise of adequate preoperative and postoperative care because of the heavy patient load and the long hours of duty for surgeons, with subsequent loss of efficiency of personnel. On the other hand, in a long-drawn-out war, there may be better organization of the medical units, with improvement in patient care. Situations existing during the Korean conflict were almost ideal. The battle line was stable; control of the air was in friendly hands; and the hospital was situated close to the battle front. The casualty load was not excessive in one site; and the investigators were able to keep patients for a longer time in the postoperative period prior to evacuation. At no time was there need of compromising patientcare because of lack of supplies or shortages of whole blood.
The lower mortality rate in the Korean conflict may be ascribed to a number of factors: the shorter evacuation time, the administration of large quantities of resuscitative fluids preoperatively and during surgery, and the routine use of antibiotics. Undoubtedly all of these factors contributed to a lower mortality rate. Although a shorter evacuation time permits the wounded to be treated soon after injury, a shorter evacuation time will tend to increase the over-all mortality rate because the more severely wounded casualties will reach the surgical hospital. Because of the availability of helicopters for evacuation during the Korean conflict, no doubt many patients were admitted to surgical hospitals who ordinarily would not have survived. Consequently more seriously wounded casualties were seen frequently in the forward surgical hospitals in Korea. The greatest single difference in the management of casualties in Korea appears to be the large quantities of blood administered throughout resuscitative periods. Beebe and De Bakey state that deaths from shock in the Fifth United States Army hospitals during World War II showed that, of 254 who died of shock following surgery, 210 (82 percent) received no blood during or after surgery. Furthermore, 87 received no blood therapy prior to surgery.2 In the deaths that occurred during the period covered by 3 months` survey, all patients who died postoperatively of either uncontrolled hemorrhage or shock had received more than five pints of blood in the first 24 hours following surgery.3
Results of detailed study of evacuation, resuscitation, and case fatality rates at the 46th Surgical Hospital in Korea from May 1, 1953, to August 1, 1953, have been reported. The average evacuation time from injury to admission was 3.6 hours and from admission to surgery 3.0 hours. Casualties with extremity wounds requiring amputations received an average of 3,500 cc. of blood in the first 24 hours following injury. Casualties with abdominal wounds, thoraco-abdominal wounds, thoracic wounds, and open fractures were given an average of 3,428 cc., 2,867 cc., 1,890 cc., and 926 cc., respectively, during the first 24 hours following injury. The highest mortality rates occurred in those casualties with abdominal wounds, nine deaths among 75 casualties (12 percent); the lowest in those casualties with open fractures, one death among 82 casualties (1.2 percent).
The over-all case fatality rate for 4,671 casualties admitted to the general surgical service over the period from January 1, 1952, to August 1, 1953, was 2.4 percent. During this period, 402 casualties with abdominal wounds were admitted to the hospital. There were 51 deaths, a case fatality rate of 12.6 percent.
The most important single factor in the improvement in mortality rates appears to be the greater amounts of blood given during resuscitation for our series than for those reported for World War II.
1. Forsee, James, H., Colonel, MC, USA: Forward Surgery of the Severely Wounded. Reprint from The American Surgeon, (Vol. XVII, 508C526), June 1951.
2. Beebe, G. W., and DeBakey, M. E.: Battle Casualties. Charles C Thomas, Springfield, Illinois, 1952.
3. Artz, C. P.: Howard, J. M.; Sako, Y.; Bronwell, A. W., and Prentice, T.: Clinical Experiences in the Early Management of the Most Severely injured Battle Casualties. Ann. Surg. 141: 285, 1955 (Chapter 2 of this volume).