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Title page Comprehensive treatment for gas gangrene of the limbs in earthquakes WANG Yue1, M.D. LU Bo1, M.D. HAO Peng1, M.D. Department of Orthopaedics, Sichuan Provincial People’s Hospital, Sichuan Academy of Medical Sciences, Chengdu, Sichuan, China DAI Kerong2*, M.D., Ph.D, Department of Orthopaedics, The Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, R.R.China Please address all correspondence to: DAI Ke-rong, MD Department of Orthopaedics Ninth People’s Hospital Shanghai Jiaotong University School of Medicine 639 Zhizaoju Road, Shanghai, 200011 P.R.China Phone: (+86)2163139920 FAX: (+86)2163139920 Email:[email protected] 2 Comprehensive treatment for gas gangrene of the limbs in earthquakes Summary Background: Mortality rates for patients with gas gangrene from trauma or surgery are as high as 25%, but they increase to 50% to 80% for patients injured in natural hazards. Early diagnosis and treatment are essential for these patients. Methods: We retrospectively analyzed the clinical characteristics and therapeutic results of 19 patients with gas gangrene of the limbs who were injured in the May 2008 earthquake in the Wenchuan district of China’s Sichuan province and treated in our hospital, seeking how best to diagnose and treat earthquake-induced gas gangrene. Results: Of 226 patients with limbs with open injuries sustained during the earthquake, 53 underwent smear analysis of wound exudates. Of those, gas gangrene was diagnosed in 19. The average elapsed time from injury to arrival at the hospital was 72 hours, from injury to definitive diagnosis was 4.3 days, and from diagnosis to conversion of negative findings on wound smear analysis to positive findings was 12.7 days. Anaerobic cultures were also obtained before wound closure. The average elapsed time from completion of surgery to recovery of normal vital signs was 6.3 days. Of the 19 patients, 16 were treated with open amputation, 2 with closed amputation, and 1 with successful limb salvage; 18 patients were successfully treated and 1 died. Conclusions: In earthquakes, rapid, accurate screening and isolation are essential to successfully treating gas gangrene and helpful in preventing nosocomial diffusion. Early and thorough 3 débridement, open amputation, and active supportive treatment can produce satisfactory therapeutic results. 4 INTRODUCTION Gas gangrene (Clostridium septicum myonecrosis) is a serious, acute, specific infection resulting from a severe open injury. The pathologic changes develop quickly and result in high mortality and disability rates.7 Large-scale natural hazards such as earthquakes lead to large numbers of patients with traumatic injuries, some of them quite complicated. How best to provide timely diagnosis and effective treatment to patients who develop gas gangrene from injuries sustained in earthquakes, so as to lower mortality rates and prevent nosocomial diffusion of infection, is a Gordian knot yet to be resolved. There are few reports about gas gangrene in earthquake-caused injuries in the medical literature. On May 12, 2008, a catastrophic earthquake with a magnitude of 8.0 on the Richter scale struck the Wenchuan district of the Sichuan province of China, after which our hospital treated 19 patients with gas gangrene in 21 limbs. Despite treating a large number of people with other kinds of injuries at the same time, we provided active treatment to those with gas gangrene, effectively preventing nosocomial diffusion and achieving a high survival rate. What follows here is our retrospective report. PATIENTS and METHODS Study targets After the earthquake, the People’s Hospital of Sichuan Province admitted 1,613 earthquake survivors between May 12 and May 31, 2008, of whom 820 had limb fractures and 226 had open limb injuries (including 157 with open limb fractures). After initially visually examining these patients at admission, we conducted wound smear bacteriologic screening in 53 patients with 5 open limb injuries. Of those, 19 patients (21 limbs) had definite gas gangrene (18 patients with open fractures and 1 patient with an open soft-tissue injury), and for 3 patients the initial diagnosis was suspected gas gangrene, but later observation proved that diagnosis incorrect. For the 19 patients who had gas gangrene, local medical agencies failed to give health-care providers any special reminder right after these patients had been extricated from rubble, so the first-aid medical teams provided only the simple wound bandaging that is normally provided for uncomplicated open injuries and transferred the patients to our hospital for treatment. The 19 patients include 9 males and 10 females, with an average age of 49.2 years (range, 8–87 years). Eighteen patients had been crushed by collapsed houses and 1 was injured by falling stones. The average time spent trapped under rubble was 16.3 hours (range, 7–68 hours). Injuries were distributed as follows: 9, left leg only; 4, right leg only; 2, both legs; 3, right arm only; and 1, left arm only. One patient had a closed chest injury, multiple rib fractures, traumatic wet lung, acute respiratory distress syndrome, disseminated intravascular coagulation, and multiorgan dysfunction. One patient sustained multiple fractures in the first and second metacarpal bones and fracture of the proximal phalanx on the left middle finger. None of the 19 patients had ever received immunosuppressive drugs. Among them, 3 had abnormal renal function; 1 patient recovered normal function after the correction of circulating blood volume, and the other 2 were treated with blood dialysis. 6 Screening examination On arrival at our hospital, the 226 patients with open limb injuries underwent initial examination in the temporary consulting rooms (figure 1) that were built especially to handle patient overflow caused by the earthquake. Routine débridement was done for those patients with small, slightly contaminated wounds who were free of any obvious symptom of infection or tissue necrosis. Of those, 53 with extensive soft-tissue damage or contaminated wounds underwent prompt sampling and smear analysis. The choice of which of four types of treatments to use was based on the results of clinical and bacteria smear analysis: 1. Patients with negative findings on smear analysis and free of any typical clinical symptoms of gas gangrene—extensive soft-tissue necrosis in local muscles; tissue that turned grayish or blackened, associated with a foul odor, a lot of blebs, and extensive effusion—were sent to the ordinary débridement room for routine débridement, and then kept in ordinary wards for further treatment. Of the study group of 53 patients, 31 received this treatment. 2. Patients with negative findings on bacteria smear analysis but who manifested some typical clinical symptom of gas gangrene (e.g., foul odor, darkened or blackened tissues) were designated as having suspected gas gangrene, sent to an infection-control operating room for wound management, and then kept in an isolation ward for patients with suspected gangrene and observed. If smear analysis findings during the observation period became positive, the patient was transferred to 7 the isolation ward immediately. For those with continuously negative smear analysis (once-daily smears) results (i.e., no Gram-positive bacilli with spores or capsules detected, and both local and general manifestations appearing better off after treatment), anaerobic cultures were obtained to verify the results of smear analysis before wound closure. If no pathologic condition recurred within 3 days of wound closure, the patient was deemed not to have gas gangrene and was released from isolation. Two patients from the study group had this treatment regimen. 3. Patients with positive results on bacteria smear analysis who were nevertheless free of typical clinical symptoms were listed as possibly having gas gangrene, sent to an infection-control operating room for wound for treatment, and then kept in an isolation ward for patients with suspected gangrene and observed. If typical clinical symptoms appeared during the observation period, the patient was transferred to an isolation ward immediately. If the results of smear analysis became negative and no pathologic condition recurred within 3 days of injury closure, then the diagnosis was not gas gangrene and the patient was transferred out of isolation. One patient from the study group had this treatment regimen. 4. Patients with positive results on bacteria smears (i.e., Gram-positive thick bacilli with spores or capsules were detected) and who had typical clinical symptoms were given a definite diagnosis of gas gangrene, sent to an infection-control operating room for treatment, and then kept in an isolation ward for further treatment. Nineteen patients from the study group had this treatment regimen. 8 Diagnosis criteria The criteria for gas gangrene are as follows: 1. Foul odor, darkened or blackened soft tissues in wounded muscle, and associated fever, crepitation, distension pain in the wounded limb, low blood pressure, and altered state of consciousness, along with the typical feathering pattern of gas in soft tissue as shown on radiographs (figure 2) 2. Gram-positive thick bacilli with spores or capsules detectable on bacteria smear analysis Once both criteria have been met, the diagnosis of gas gangrene is definite. If only one criterion is met, the patient is considered to have suspected gas gangrene. If the patient has the typical clinical manifestation but the initial bacteria examination findings are negative, then daily smear analysis must be conducted for 3 successive days. If Gram-positive thick bacilli with spores or capsules can then be detected at any time during those 3 days, then gas gangrene is definitely the correct diagnosis. Because the number of earthquake survivors who arrived at our hospital simultaneously was quite large and because of the possibility that patients with suspected gas gangrene could be exposed to infection during radiographic examination, which could result in infection diffusion, we did not obtain radiographs for all patients as we usually would have done. 9 Data for the following parameters were recorded for all patients with definite gas gangrene and for those suspected of having it: 1. The time elapsed from injury to having a suspected diagnosis, from then to having a definite diagnosis, from then to recovery of normal vital signs after surgery, and from then until wound bacteria culture results became negative 2. Corresponding clinical symptoms and signs and any changes in them 3. Changes in laboratory examination results for such tests as hemoglobin (Hgb) level, packed red blood cell volume, serum total protein, albumin level, blood sugar level, aspartate aminotransferase (AST) level, and alanine aminotransferase (ALT) level during various treatment stages (We report data here as mean values and standard deviation. SPSS statistical software [version 12.0; SPSS Inc., Chicago, IL, USA] was used, and the data were analyzed with repeated measures analysis of variance.) 4. Drug use, transfusion of blood or plasma, and corresponding effects 5. The type of associated bacterial infection and the length of the positive-to-negative conversion period Criteria for exclusion If no Gram-positive thick bacilli with spores or capsules were detected in the successive three wound bacteria smear analyses (once per day for successive 3 days) and if the patient’s condition was obviously better after débridement, then the patient was designated as not having gas gangrene. 10 Wound management and sterilization of isolation wards This is the procedure for surgical treatment for both patients with suspected gangrene and those with diagnosed gangrene: Obtain a sample of wound secretions during surgery for bacteria smear examination. Apply adequate physiologic saline solution to repeatedly wash the wound. Treat the wound with hydrogen peroxide solution and apply a wet compress with iodoform gauze. Thoroughly remove any infectious agents. Débride necrotic tissues insofar as possible. For patients with ischemic necrotic limbs, carry out first-stage amputation. As a routine, administer clindamycin and amoxicillin to all patients with suspected gas gangrene and to those with diagnosed gangrene, to prevent and treat infection. For those infected with a combination of different bacteria, administer empiric antibiotic treatment with levofloxacin, adjusting the dosage until the results of a bacteria culture and drug sensitivity test are available. Moreover, we corrected electrolyte imbalances, transfused blood or blood plasma, and provided hyperbaric oxygen treatment in chambers specialized for patients with gas gangrene. During hyperbaric oxygen treatment, patients breathed 100% oxygen for 150 minutes: We increased the pressure to the equivalent of 2.5 kPa after 30 minutes, maintained that level for 60 11 minutes, and then decreased the pressure for 60 minutes. They were treated once every 8 hours the first day, once every 12 hours the second and third days, and then once a day from the fourth day until wound secretion bacteria smear results were negative three successive times (one smear examination per day and continuing for successive 3 days). All disposable medical items used in wards for patients with suspected gangrene and in isolation wards should be incinerated. Other apparatuses or instruments should be separately sealed, transported, and cleaned and disinfected, and sterilized at high temperature and high pressure before being used in other procedures. We used air-sterilization facilities for continuous sterilization, and all surfaces and operating-room articles were sterilized with benzalkonium bromide daily. Wounds should be closed only after patients with diagnosed gas gangrene meet the criteria of wound closure. Patients in isolation cannot be moved to regular wards until there has been no recurrence of bacteria within 3 days of wound closure. Patients’ personal articles must be sterilized before they leave isolation. Hyperbaric chambers specialized for patients with gas gangrene must be thoroughly sterilized after each use, including chamber surfaces, the air, and the floor and walls of the therapy room. Criteria for terminating isolation After surgery on the limb with gas gangrene, the wound can be closed if no Gram-positive thick bacilli with spores or capsules are detected in three successive wound bacteria smear analyses (once per day for 3 successive days). If there is no recurrence of bacteria within the following 3 12 days, the patient can be removed from the isolation ward. To prevent infection recurrence after wound closure, anaerobic cultures should be conducted concurrent with bacteria smear analysis before wound closure to verify the results of smear analysis. RESULTS Of the 53 patients seen in an initial screening, 21 were sent to wards for patients with suspected gas gangrene, 18 had wounds with a definite diagnosis of gas gangrene after observation, and 3 with suspected gangrene were found, after further observation and treatment, not to have gangrene. However, gangrene was missed in 1 patient at the initial screening, and the patient was sent to an ordinary ward. Both thighs of this patient had ischemic necrosis because they were trapped by earthquake rubble for 68 hours. When the patient arrived at the temporary consulting room, the results of the wound bacteria smear analysis appeared to be negative and the patient had no typical clinical symptom of gas gangrene; open amputation at the lower thigh was performed on both legs. However, on the second day after surgery, the wounds emitted a foul odor and the wounded muscle turned black and necrotic and developed profuse effusion and blebs. A second smear analysis was conducted, and bacilli with spores and capsules were detected. The patient was immediately transferred to an isolation ward and underwent a second débridement, and the patient’s condition was gradually controlled. In all patients studied, the limb wounds were extensive and deep, some reaching to the bone surface or joint cavity, with long bones or joint cavities exposed. All wounds were severely contaminated and contained with a great deal of dust, sand, or crushed stones and emitted a 13 heavy stench that was perceptible even when the wounds were wrapped with multiple layers of dressing. The skin surrounding the wounds appeared pale, varicose, and bright and were highly tense; normal skin texture had disappeared. An extensive area of soft tissues, including muscles, showed color changes (presenting as grayish, wine colored, or purple-black). The involved muscle had lost elasticity, failed to contract on stimulation, and appeared stagnant and wan, like boiled meat. There was extensive effusion, presenting as a malodorous thin, bloody secretion. Crepitation was apparent in 73.7% of patients, and blebs appeared on their wounds when they were under pressure; 68.4% of patients had distension pain of the wounded limb, on which routinely provided analgesia had no effect; and 31.6% patients presented with low blood pressure (table 1). We found that in earthquake survivors without gas gangrene, wounds may be similarly extensive and wounded muscle may be similarly blackened and may fail to contract on stimulation, but the degree of wound contamination was comparatively lighter than in patients with gangrene. Also less severe in patients without gangrene were degree of wound malodorousness, degree of tumefaction of skin surrounding the wound, degree of skin tension, and amount of effusion from the wound. These patients also had no blebs, crepitation, or distension pain. The presence of fever was not consistent in earthquake survivors. The average body temperature of the group was 38.4° ± 0.7°C (range, 37.3°C–40.4°C) on arrival at the hospital; 8 patients had a temperature of <38°C, 9 had a temperature between 38.1°C and 39.9°C, and 2 had a temperature of >39.1°C. 14 Table 2 provides laboratory results after initial examination on arrival at the hospital, during the period when patients’ conditions were primarily controlled, and during the transition period from positive to negative findings on smear analysis for each patient. The average values for Hgb, hematocrit (Hct), total protein, albumin, AST, and ALT were significantly improved after treatment. This suggested that patients gradually became healthier as parameters were corrected throughout treatment. Among the 19 patients with gas gangrene, 16 underwent amputation immediately because of ischemic necrosis and severe infection, and the other 3 underwent limb-salvage débridement. Among the 16, 13 patients (13 limbs) underwent open amputation and 3 patients (5 limbs) underwent closed amputation initially that evolved to open amputation (5 limbs) because gas gangrene had not been completely controlled. Among the 3 patients who underwent limb-salvage débridement, 2 later underwent closed amputation (2 limbs) because of diffusion of gas gangrene associated with regional limb necrosis, and 1 underwent successful limb salvage (figure 3). The latter patient arrived at the hospital 7 hours after injury, which is the earliest point in time that any of the 19 patients with gas gangrene received treatment. After thorough débridement, local necrotic tissues were removed, the wound dressing was replaced every day to remove newly formed necrotic tissues, and the wounds and the patients’ general conditions gradually improved. Anaerobic cultures were obtained, in addition to smear analyses, before wound closure to verify negative smear analysis findings, and limb salvage eventually succeeded. Among the 31 patients free of gas gangrene, 17 underwent amputation because of crush syndrome and limb necrosis, and the other 14 underwent successful limb salvage. 15 The average amounts of transfused erythrocyte suspension and of transfused fresh frozen plasma were 4.4 U (range, 0–16 U) per patient and 1430 mL (range, 0–5200 mL) per patient, respectively. Among the 19 patients (21 limbs) with gas gangrene, combined bacterial infections detected by wound culture included Acinetobacter calcoaceticus-baumannii (6 patients), Enterobacter cloacae (3), Enterococcus faecalis (3), Escherichia coli (3), Staphylococcus aureus (2), Enterobacter amnigenus (1), S. epidermidis (1), Alcaligenes faecalis (1), Klebsiella pneumoniae (1), Morganella morganii (1), Pediococcus pentosaceus (1), S. haemolyticus (1), and Moraxella catarrhalis (1). The time elapsed for conversion of C. perfringens from positive to negative findings on bacteria smear was 15.1 ± 7.9 days for those with combined bacteria infection (14 patients) and 3.6 ± 6.4 days for those without combined bacteria infection (5 patients), which demonstrated that the conversion period was obviously shorter for patients without combined bacterial infection. During treatment, abnormal renal function was diagnosed in 3 patients: 1 patient recovered after blood volume improved, 1 recovered after blood dialysis, and 1 died from multiorgan failure caused by multiple injuries. Because of excessive wound effusion before and after surgery, 5 patients developed hypokalemia, with output ranging between 2.8 and 3.32 mmol/L, and recovered after correction of electrolyte imbalances. In the studied group, 2 patients who underwent closed amputation healed by first intention. For patients who underwent open amputated or limb salvage, their wounds were closed after wound secretion cultures produced 16 negative results. No infection recurrence was observed. Two patients were given 12 U and 36 U of blood platelets each during dialysis. Among the 19 patients with definite gas gangrene, 18 were successfully treated and 1 died. The patient who died had gas gangrene of the right leg, associated with closed chest injury and multiple rib fractures; the causes of death were acute renal failure, traumatic wet lung, acute respiratory distress syndrome, disseminated intravascular coagulation, and multiorgan failure. The average time elapsed from injury to arrival at the hospital was 72 hours (range, 7–144 hours), from injury to definite diagnosis of gas gangrene was 4.3 days (range, 3–7 days), from completion of surgery to recovery of normal vital signs was 6.3 days (range, 4–18 days), and from definite diagnosis of gas gangrene to negative findings on wound bacteria smears was 12.7 days (range, 0–23 days). DISCUSSION Clinical characteristics and related treatment of earthquake survivors with gas gangrene Gas gangrene is most often caused by severe open injury. Common nosogenetic bacteria include C. perfringens, C. aerogenes capsulatus, edematigenous bacillus, septicemic bacillus, and C. histolyticum. These bacilli generate various enzymes and toxins that cause tissue edema, necrosis, toxemia, and quick diffusion of pathologic changes,2 in which case both mortality rates and disability rates will be high. Spontaneous gas gangrene is related to colon cancer, leukocythemia, diabetes, and drug-induced human immunodeficiency virus.3-5, 8 17 All patients in the study group were injured in the earthquake, and all except 1 had limbs injured by collapsed houses, underwent a long period of limb entrapment (an average of 16.3 hours), and had severe local soft-tissue injury. Because of the obstructed motor-vehicle traffic and difficulties in extracting wounded persons from rubble after the earthquake, patients could not immediately be sent to a hospital. On average, they were transported to a hospital 3.0 days after injury, and the average time from injury to definitive diagnosis was 4.3 days, so early and thorough débridement was impossible, which resulted in generation and diffusion of gas gangrene, leading to a high amputation rate.1 All wounds featured foul odors, color changes of the muscles and other soft tissues, and extensive effusion; 94.7% of patients had fever, 73.7% had crepitation, 68.4% had distension pain in the injured limbs, and 31.6% had low blood pressure. All patients had anemia and hypoproteinemia to some degree on arrival at the hospital. Erythrocyte suspension and fresh frozen plasma were transfused to maintain a stable internal environment. The average transfusion of erythrocyte suspension was 4.4 U per patient, with a maximum of 16 U; the average transfusion of fresh frozen plasma was 1430 mL per patient, with a maximum of 5200 mL. Owing to serious wound contamination, most of the patients had combined infections caused by more than one type of bacteria, so appropriate bacteria cultures were obtained to allow timely adjustment of antibiotics. The positive-to-negative conversion period after surgery was significantly shorter for patients without combined bacterial infections than for those with such infections. As far as the impacts of types and quantities of bacteria on infection were concerned, 18 we did not conduct relevant statistic processing because of the small size of the available sample group, but that is an issue worth further study. The catastrophic earthquake in China wounded large numbers of persons who were sent to hospitals, and many of them were in critical condition on arrival, leaving no time to wait for the results of bacteria cultures. In that situation, we deemed repeated bacteria smear examinations to be more practical than cultures. By the time these patients’ wounds had been closed, the number of in-hospital patients had been gradually reduced, so anaerobic cultures could be conducted to verify the results of smear examinations and to ensure that there were no infection recurrences after wound closure. Because of extensive effusion from their wounds, the patients were subject to electrolyte imbalances during treatment. Five of them developed hypokalemia. Regularly retesting for pathology, treatment aimed at achieving homeostasis, and reduction of wound effusion help prevent wound infection. For patients with abnormal renal function, blood dialysis can be used if necessary. When blood dialysis must be lengthy, care should be taken to supplement blood plasma and blood platelets to improve thromboxane function. Hyperbaric oxygen treatment can obviously inhibit growth of anaerobic bacteria, reduce or stop the production of clostridial α-toxin by C. perfringens, suppress peroxidase in necrotic tissue, enhance the clearance of Clostridium, and halt edema and gas production in the tissue. Thanks to these and other effects, hyperbaric oxygen therapy has a favorable effect on edema and the healing of hypoxic wounds. Moreover, the increased wound oxygen tension achieved with hyperbaric oxygen therapy promotes capillary angiogenesis and improves healing. 19 Furthermore, it can increase the host’s antimicrobial defenses and has a direct bacteriostatic effect on anaerobic organisms. In our experience, hyperbaric oxygen therapy can assist wound healing by improving the patient’s general condition and correcting blood-loss anemia and hypoproteinemia. It may also help control gas gangrene. Diagnostic process for suspected gas gangrene Any patients who have survived an earthquake should undergo careful wound examination on arrival at a hospital. If the wound emits a foul odor, if the soft tissues in the wounded muscle have changed color, if there is extensive effusion from the wound, or additionally if there are associated clinical manifestations such as fever, crepitation, distension pain in the wounded limb, or low blood pressure, a bacteria smear should be immediately obtained and the patient should be transferred to a special infection isolation ward. If Gram-positive bacilli with spores or capsules are detected during the smear examination, the patient should immediately be treated for gas gangrene infection with débridement or amputation, and then sent to a gas gangrene isolation ward. If no Gram-positive bacilli with spores or capsules are detected during two successive smear examinations, the patient can be transferred for surgery into an operating room under special infection-control conditions, and then sent to an isolation ward for suspected infections within an infection isolation ward. Isolation cannot be terminated until there is no bacteria recurrence within 3 days of wound closure. Those patients without typical clinical manifestation but whose smears produce positive results should be treated as having suspected gas gangrene. Within a short period, 1613 patients with 226 open injuries were treated. Among them, 19 patients with gas gangrene were treated and were free of nosocomial infection diffusion, 20 which showed that the diagnosis and treatment processes that we used were reasonable. On the basis of our success, and because earthquakes injure a large quantity of persons within a short period, we deem it necessary to set up a screening and management process especially for gas gangrene to deal with similar large-scale public-health emergencies. Integrated with the experience we obtained after the earthquake, the ideal screening process should include the following facilities and measures: Initial examination rooms, ordinary patient diagnosis rooms, and examination rooms for those suspected of having gas gangrene should be set up separately. Three types of operating rooms—general operating room, infection-control operating room, and specialized infection operating room—should be set up to deal with ordinary wounds, wounds with suspected gas gangrene, and wounds with diagnosed gas gangrene, respectively. Ordinary wards, observation wards for those suspected to have gas gangrene, and isolation wards for those with diagnosed gas gangrene should be set up separately. For initial diagnosis, physicians should carry out a first-stage local and general examination to distinguish ordinary patients from those suspected of having gas gangrene. Patients with suspected gas gangrene should be sent to an examination room used only for such patients; relevant wound specimens should be sent for bacterial examination. The second-stage examination should be integrated with clinical manifestations. Patients with definitive diagnoses should be sent to the special infection operating room and 21 placed in an isolation ward after surgery. Patients with suspected gas gangrene should be sent to the infection-control operating room for treatment. The third-stage examination should be conducted during surgery by sampling and sending specimens for bacterial examination. If the results are positive, the patient should be placed in an isolation ward after surgery; if negative, then in an observation ward for those with suspected infection. The fourth-stage clinical and bacteriologic examination should be continuously conducted until a definite diagnosis is obtained. In sum, the process that we recommend can be briefly described as a three-part system for facilities and a four-stage examination (figure 4). Timing and types of surgery for earthquake survivors with gas gangrene Patients with gas gangrene face a high mortality rate of up to 25%, whereas the mortality rate for those with limb gas gangrene caused by injury during natural hazards is reported to be even higher, between 50% and 80%.6 Early diagnosis and treatment are essential for patients with gas gangrene. Once gangrene has been definitely diagnosed, these patients should be immediately provided with extensive débridement and effective antibiotic treatment. However, because patients involved in earthquakes generally sustain severe injuries and are always sent to a hospital long after being injured, treatment is more challenging. In our study group, patients’ limbs had been severely crushed, soft tissues had been severely injured, diagnosis was quite delayed, gas gangrene had developed before diagnosis, there were multiple generalized symptoms, and the optimum time for early-stage extensive débridement and limb salvage had 22 already passed. Among the 19 patients with gas gangrene, only 1 underwent successful limb salvage; the injured limbs in all of the other patients had to be amputated. However, thanks to timely identification of patients with gas gangrene from among the numerous patients with open injuries, prompt provision of surgery, and provision of active general support treatment after surgery and treatment with hyperbaric oxygen, only 1 patient died and a high salvage rate was achieved. Among those 19 patients, 18 underwent amputation because of delayed diagnosis, 13 of whom underwent open amputation, 2 underwent closed amputation, and 3 underwent open amputation after failure of closed amputation. In our view, for those with severe soft-tissue injury sustained during earthquakes and with a definitive diagnosis of gas gangrene of the injured limbs, thorough débridement should be provided immediately and open amputation should be performed if necessary. In addition, wound closure by first intention should be undertaken especially for those patients with combined bacterial infection, in order to strengthen infection control and reduce the possibility of infection recurrence or of a second amputation. In patients with gas gangrene of the limb extremities, wound closure by first intention is acceptable if the patients’ general condition is good and the amputated plane is far from the foci. Before wound closure, however, bacteria smears should be obtained routinely, and these patients should be closely monitored after surgery. In the case of infection recurrence, timely removal of sutures to open the wound is of pivotal importance. The patients we studied had combined severe limb extrusion and soft-tissue necrosis, so the amputation rate was higher than for general patients with gas gangrene. Among the 3 patients in whom limb salvage was attempted, the procedure 23 was successful for only 1, which shows that gas gangrene sustained during earthquakes presents special problems. CONCLUSIONS In earthquakes, rapid, accurate screening and isolation are essential to successfully treating gas gangrene and helpful in preventing nosocomial diffusion. Early and thorough débridement, open amputation, and active supportive treatment can produce satisfactory therapeutic results. References 1. Ateşalp AS, Erler K, Gür E, Solakoglu C. Below-knee amputations as a result of land-mine injuries: comparison of primary closure versus delayed primary closure. J Trauma 1999; 47: 724–7. PMID:10528608 2. Bryant AE, Chen RYZ, Nagata Y, Wang Y, Lee CH, Finegold S, et al. Clostridial gas gangrene. I. Cellular and molecular mechanisms of microvascular dysfunction induced by exotoxins of Clostridium perfringens. J Infect Dis 2000; 182: 799–807. PMID:10950744 3. Carter SA, Tate RB. The relationship of the transcutaneous oxygen tension, pulse waves and systolic pressures to the risk for limb amputation in patients with peripheral arterial disease and skin ulcers or gangrene. Int Angiol 2006; 25: 67–72. PMID:16520727 4. El-Masry S. Spontaneous gas gangrene associated with occult carcinoma of the colon: a case report and review of literature. Int Surg 2005; 90: 245–7. PMID:16548324 5. Lanting B, Athwal GS, Naudie DD. Spontaneous Clostridium perfringens myonecrosis of the shoulder: a case report. Clin Orthop Relat Res. 2007; 461: 20–4. PMID:17483728 6. Patiño JF, Castro D, Valencia A, Morales P. Necrotizing soft tissue lesions after a volcanic 24 cataclysm. World J Surg 1991; 15: 240–7. PMID:2031361 7. Perry BN, Floyd WE 3rd. Gas gangrene and necrotizing fasciitis in the upper extremity. J Surg Orthop Adv 2004; 13: 57–68. PMID:15281401 8. Zgonis T, Stapleton JJ, Girard-Powell VA, et al. Surgical management of diabetic foot infections and amputations. AORN J 2008; 87: 935–46. PMID:18512303 25 Table Table 1: Main clinical signs during hospitalization Blood Change in Distension pain Extensive Foul smell wound color pressure Crepitation effusion Fever decrease No. of patients 13 19 19 14 19 18 6 Percentage of 68.4 100 100 73.7 100 94.7 31.6 total group Table 2: Laboratory indicators at various stages of treatment Time period Total protein Albumin Hgb (g/L) Hct (%) (g/L) (g/L) AST (U/L) ALT (U/L) On admission 73.6 ± 24.3 14.4 ± 7.1 48.1 ± 8.8 26.4 ± 5.9 264 ± 350 90.4 ± 109.7 General condition 85.3 ± 22.4 25.7 ± 6.3 55.7 ± 11.7 29.8 ± 5.4 138.8 ± 229.4 64.3 ± 75.8 100.7 ± 16.7 30.4 ± 3.7 62.8 ± 7.9 33.5 ± 8.6 41.8 ± 13.4 33.1 ± 26.4 <0.01 <0.01 <0.01 <0.01 <0.05 <0.05 primarily under control Transition of smear findings from positive to negative P Value ALT = alanine aminotransferase; AST = aspartate aminotransferase; Hct = hematocrit; Hgb = hemoglobin. 26 Figure and Legend Figure 1: The temporary consulting rooms built for initial examination of patients injured in the earthquake. Figure 2: Radiography showed the typical feathering pattern of gas in the soft tissues of the foot. 27 Figure 3: Successful limb salvage in a 15-year-old girl with gas gangrene of the forearm. The wounds were severely contaminated, emitting a foul odor, with the surrounding skin appearing pale, varicose, bright, and highly tense. An extensive area of soft tissues, including muscles, showed changes in color. The involved muscles lost elasticity and failed to contract on stimulation (A). Bacteria smear findings were positive, with Gram-positive thick bacilli present with spores and capsules (B). Débridement of necrotic soft tissue was conducted. The forearm was successfully salvaged (C). 28 Figure 4: The screening examination and diagnosis process for gas gangrene. The first stage consisted of a clinical examination and the second, third, and fourth stages consisted of clinical and bacteriologic examinations. 29