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Objective. Prehospital transport, resuscitation, and operative intervention are all critical to the care of the penetrating trauma victim. We determined which factors most affected mortality in patients with penetrating abdominal vascular injuries.Methods. Consecutive patients with penetrating abdominal vascular injuries from an urban Level I trauma center from January 1993 to December 1998 were identified from the trauma registry and their charts reviewed. All patients who died prior to operative intervention were excluded. Data collected included mortality, age, scene time (ST), EMS transport time (TT), time in the emergency department (ED), initial systolic blood pressure in the ED (BP), operating time, intraoperative estimated blood loss (EBL), and worst base deficit in the first 24 h (BD). These variables were compared between nonsurvivors and survivors by univariate ANOVA. Multivariate ANOVA (MANOVA) determined independent effects on mortality.Results. Forty-six penetrating abdominal vascular injuries were identified in 31 patients, 11 of whom died (38.7%). Examining prehospital parameters, mean ST averaged 16.5 ± 3.6 min, while TT was 31.8 ± 7.1 min. For ED parameters, initial BP was 94.8 ± 6.4 mm Hg and initial heart rate was 109 ± 7 beats per minute. Mean operative EBL for all patients was 3518 ± 433 ml. The mean BD for all patients was −12.9 ± 1.8. Significant differences were noted in the univariate analysis between survivors and nonsurvivors for BD (P < 0.0001), BP (P = 0.0062) and EBL (P = 0.0002). MANOVA revealed that only base deficit (P < 0.0001) had an independent effect on mortality.Conclusions. In patients with penetrating abdominal vascular injuries who survive their ED stay, adverse physiologic parameters reflecting the adequacy of resuscitation are more predictive of mortality than identifiable prehospital parameters. [Copyright &y& Elsevier]

Preventing hurricane-related injuries (HRI) has historically centered on the pre-event and event phases of the disaster. To date, no study has focused on injuries occurring during the postevent phase. We examined HRI that occurred after Hurricane Isabel struck a U.S. urban city. HRI presenting 1 week prior to the hurricane were collected from emergency department electronic records. HRI that presented to our level 1 trauma center were prospectively collected for 1 week after the hurricane. Nine hundred seventy-eight patients with possible HRI were identified. Fifty-one patients with trauma directly attributed to the hurricane were used for analysis. The number of HRI occurring before, during, and after the hurricane were 7 (14%), 3 (6%), and 41 (80%), respectively. The majority of HRI (37%) occurred on posthurricane day 1. Head, chest, upper and lower extremities accounted for 9 (18%), 8 (16%), 13 (26%), and 14 (28%) of HRI. More than one third of HRI patients were admitted to the hospital, and 12 (24%) underwent an operation. The average hospital length of stay was 4.7 days. Of our trauma alerts, 75 per cent had an Injury Severity Score (ISS) >8, and 20 per cent had an ISS >15. Tree-related injuries (TRI) accounted for 59 per cent of HRI. Males, ages 50-60, had the highest incidence of injury (63%). Significant injuries occur in the wake of a hurricane. Optimization of disaster preparation must include prevention strategies targeted to the postevent recovery phase of disasters. [ABSTRACT FROM AUTHOR]

Background: Several recent military and civilian trauma studies demonstrate that improved outcomes are associated with early and increased use of plasma-based resuscitation strategies. However, outcomes associated with platelet transfusions are poorly characterized. We hypothesized that increased platelet:red blood cells (RBC) ratios would decrease hemorrhagic death and improve survival after massive transfusion (MT)., Methods: A transfusion database of patients transported from the scene to 22 Level I Trauma Centers over 12 months in 2005 to 2006 was reviewed. MT was defined as receiving ≥ 10 RBC units within 24 hours of admission. To mitigate survival bias, 25 patients who died within 60 minutes of arrival were excluded from analysis. Six random donor platelet units were considered equal to a single apheresis platelet unit. Admission and outcome data associated with the low (>1:20), medium (1:2), and high (1:1) platelet:RBC ratios were examined. These groups were based on the median value of the tertiles for the ratio of platelets:RBC units., Results: Two thousand three hundred twelve patients received at least one unit of blood and 643 received an MT. Admission vital signs, INR, temperature, pH, Glasgow Coma Scale, Injury Severity Score, and age were similar between platelet ratio groups. The average admission platelet counts were lower in the patients who received the high platelet:RBC ratio versus the low ratio (192 vs. 216, p = 0.03). Patients who received MT were severely injured, with a mean (± standard deviation) Injury Severity Score of 33 ± 16 and received 22 ± 15 RBCs and 11 ± 14 platelets within 24 hours of injury. Increased platelet ratios were associated with improved survival at 24 hours and 30 days (p < 0.001 for both). Truncal hemorrhage as a cause of death was decreased (low: 67%, medium: 60%, high: 47%, p = 0.04). Multiple organ failure mortality was increased (low: 7%, medium: 16%, high: 27%, p = 0.003), but overall 30-day survival was improved (low: 52%, medium: 57%, high: 70%) in the high ratio group (medium vs. high: p = 0.008; low vs. high: p = 0.007)., Conclusion: Similar to recently published military data, transfusion of platelet:RBC ratios of 1:1 was associated with improved early and late survival, decreased hemorrhagic death and a concomitant increase in multiple organ failure-related mortality. Based on this large retrospective study, increased and early use of platelets may be justified, pending the results of prospective randomized transfusion data.

Non-closure of abdominal fascia and the resultant open abdomen after laparotomy has become a major advance in the management of critically ill or injured patients. The benefits of open abdomen are many and include the prevention of intra-abdominal hypertension and the consequent abdominal compartment syndrome. Appropriately and exquisitely managed, it can provide all the benefits and prevent highly morbid complications of leaving the abdomen open. This review will provide some insights into such management.

Background: Construction of gastrointestinal anastomoses utilizing stapling devices has become a familiar procedure. In elective surgery, studies have shown no significant differences in complications between stapled and sutured anastomoses. Controversy has recently arisen regarding the accurate incidence of complications associated with anastomoses in the trauma patient. The objective of this multi-institutional study was to determine whether the incidence of postoperative complications differs between stapled and sutured anastomoses following the emergent repair of traumatic bowel injuries., Methods: Using a retrospective cohort design, all trauma registry records from five Level I trauma centers over a period of 4 years were reviewed., Results: A total of 199 patients with 289 anastomoses were identified. A surgical stapling device was used to create 175 separate anastomoses, while a hand-sutured method was employed in 114 anastomoses. A complication was defined as an anastomotic leak verified at reoperation, an intra-abdominal abscess, or an enterocutaneous fistula. The mean abdominal Abbreviated Injury Scale score and Injury Severity Score were similar in the two cohort groups. Stapling and suturing techniques were evenly distributed in both small and large bowel repairs. Seven of the total 175 stapled anastomoses and none of the 114 hand-sewn anastomoses resulted in a clinically significant leak requiring reoperation (RR = undefined, 95% CI 1.08-infinity, p = 0.04). Each anastomotic leak occurred in a separate individual. Nineteen stapled anastomoses and four sutured anastomoses were associated with an intra-abdominal abscess (RR = 2.7, 95% CI 0.96-7.57, p = 0.04). Enterocutaneous fistula formation was not statistically associated with either type of anastomoses (stapled cohort = 3 of 175 and sutured cohort = 2 of 114). Overall, 22 (13%) stapled anastomoses and 6 (5%) sutured anastomoses were associated with an intra-abdominal complication (RR = 2.08, 95% CI 0.89-4.86, p = 0.076)., Conclusion: Anastomotic leaks and intra-abdominal abscesses appear to be more likely with stapled bowel repairs compared with sutured anastomoses in the injured patient. Caution should be exercised in deciding to staple a bowel anastomosis in the trauma patient.

Our hypothesis is that in an established Level I trauma center general trauma surgeons should repair peripheral vascular injuries even in stable patients when there is time for a vascular consult. We reviewed all penetrating peripheral vascular injuries in stable patients operated on by nine experienced general trauma surgeons (1993-1996). Outcome measures were amputation, nerve damage, and vascular complications. There were 43 patients with 44 peripheral vascular injuries identified. Sixty per cent were from stab wounds. There were 27 arterial injuries (carotid four, subclavian one, vertebral two, axillary three, brachial eight, ulnar one, radial two, femoral five, and anterior tibial one). There were three venous injuries (one each subclavian, axillary, and popliteal). There were 14 combined injuries (vertebral two, femoral nine, and popliteal three). There were no mortalities. Morbidity was limited to patients with lower extremity injuries. In the nine patients with combined femoral vessel injury there were three complications (nerve damage, thrombosed arterial repair, and thrombosed venous repair). In the four patients with popliteal venous injuries there were two complications, both venous thrombosis. Our early arterial patency rate was 97.6 per cent. These data support the hypothesis that general surgeons with trauma experience can provide effective treatment of peripheral vascular injuries. The significance of these findings in improving the image of trauma surgery as a career is discussed.

Background: The management of colon injuries that require resection is an unresolved issue because the existing practices are derived mainly from class III evidence. Because of the inability of any single trauma center to accumulate enough cases for meaningful statistical analysis, a multicenter prospective study was performed to compare primary anastomosis with diversion and identify the risk factors for colon-related abdominal complications., Methods: This was a prospective study from 19 trauma centers and included patients with colon resection because of penetrating trauma, who survived at least 72 hours. Multivariate logistic regression analysis was used to compare outcomes in patients with primary anastomosis or diversion and identify independent risk factors for the development of abdominal complications., Results: Two hundred ninety-seven patients fulfilled the criteria for inclusion and analysis. Overall, 197 patients (66.3%) were managed by primary anastomosis and 100 (33.7%) by diversion. The overall colon-related mortality was 1.3% (four deaths in the diversion group, no deaths in the primary anastomosis group, p = 0.012). Colon-related abdominal complications occurred in 24% of all patients (primary repair, 22%; diversion, 27%; p = 0.373). Multivariate analysis including all potential risk factors with p values < 0.2 identified three independent risk factors for abdominal complications: severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis. The type of colon management was not found to be a risk factor. Comparison of primary anastomosis with diversion using multivariate analysis adjusting for the above three identified risk factors or the risk factors previously described in the literature (shock at admission, delay > 6 hours to operating room, penetrating abdominal trauma index > 25, severe fecal contamination, and transfusion of > 6 units blood) showed no statistically significant difference in outcome. Similarly, multivariate analysis and comparison of the two methods of colon management in high-risk patients showed no difference in outcome., Conclusion: The surgical method of colon management after resection for penetrating trauma does not affect the incidence of abdominal complications, irrespective of associated risk factors. Severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis are independent risk factors for abdominal complications. In view of these findings, the reduced quality of life, and the need for a subsequent operation in colostomy patients, primary anastomosis should be considered in all such patients.

Background: The purpose of this study was to determine the utility of magnetic resonance cholangiopancreatography (MRCP) in the evaluation of pancreatic duct trauma and pancreas-specific complications., Methods: Ten hemodynamically stable patients with clinically suspected pancreatic injury related to blunt abdominal trauma (n = 8), penetrating trauma (n = 1), or iatrogenic trauma (n = 1) underwent MRCP. Two abdominal radiologists conducted a review of the MRCPs to assess for the presence or absence of pancreatic duct trauma and pancreas-specific complications such as pseudocysts. The MRCP findings were correlated with endoscopic retrograde cholangiopancreatograms (n = 2), surgical findings (n = 1), computed tomographic scans (n = 10), and with clinical, biochemical or imaging follow-up (n = 10)., Results: Diagnostic quality MRCPs were obtained in each of the 10 patients. A mean imaging time of 5 minutes was required to perform the MRCPs. Pancreatic duct injuries were detected in four patients; pseudocysts were detected in three of these four patients. The pancreatic duct injuries in three patients were acute or subacute. In one of the three patients, disruption of a side branch of the pancreatic duct diagnosed with MRCP was not detected with endoscopic retrograde cholangiopancreatography but was confirmed surgically. In the fourth patient, the pancreatic duct injury was chronic; MRCP revealed a posttraumatic stricture in this patient who had sustained blunt abdominal trauma 17 years previously. In the remaining six patients, pancreatic duct trauma was excluded with MRCP. The information derived from the MRCPs was used to guide clinical decision-making in all 10 patients., Conclusions: MRCP enables noninvasive detection and exclusion of pancreatic duct trauma and pancreas-specific complications and provides information that may be used to guide management decisions.

The case of a young woman presenting with fever, abdominal distention, and diarrhea is presented. While hospitalized, she developed peritonitis, and a laparotomy was performed emergently. Intraoperative and pathologic examinations are highly suggestive of Salmonella typhi as an etiology for her symptoms and eventual perforation. Salmonella enteritis can be a difficult diagnosis to make, but in most cases it is a self-limited disease process. In a minority of cases, multidrug antibiotic therapy may be required secondary to an increasing prevalence of resistant strains. Patients who perforate require prompt operation to limit morbidity and mortality. Outcome is significantly improved in those patients by directed resection of the affected segment of bowel and by aggressive perioperative care.

Minimally invasive surgery already has established itself as a useful tool in the management of trauma. The future holds exciting possibilities for this field, borne and fostered by innovative developments in imaging, computer technology, and artificial intelligence. The next millennium may witness the disappearance of trauma surgery as it is known today.

Reactive oxygen species have been implicated in the etiology of multiorgan dysfunction syndrome and infectious complications in trauma patients by either direct cellular toxicity and/or the activation of intracellular signaling pathways. Studies have shown that the antioxidant defenses of the body are decreased in trauma patients; these include glutathione, for which N-acetylcysteine is a precursor, and selenium, which is a cofactor for glutathione. Eighteen trauma patients were prospectively randomized to a control or antioxidant group where they received N-acetylcysteine, selenium, and vitamins C and E for 7 days. As compared with the controls, the antioxidant group showed fewer infectious complications (8 versus 18) and fewer organs dysfunctioning (0 versus 9). There were no deaths in either group. We conclude that these preliminary data may support a role for the use of this antioxidant mixture to decrease the incidence of multiorgan dysfunction syndrome and infectious complications in the severely injured patient. This remains to be confirmed in larger trials.

Critically ill patients in the surgical intensive care unit (SICU) continue to require operative procedures. Traditionally, this has meant the transport of these critically ill patients out of the safe, monitored confines of the SICU to the operating room (OR). This can be hazardous to the patient, as well as expensive. Performing the procedures in the OR can avoid both the dangers of transport and the expense of the OR. Herein is a descriptive study of 80 procedures performed on 36 patients in the SICU. We believe that these data show that the SICU can be a cost-effective alternative to the OR in a trauma center in critically ill patients. Significant cost savings may be realized without increasing the iatrogenic or infectious complications.

Percutaneous tracheostomy has been touted as the preferred route of tracheostomy. However, to date, no prospective randomized study comparing bedside percutaneous (BP) to bedside open (BO) tracheostomy has been performed. Surgical intensive care unit (sICU) patients were randomized to receive either a BP or a BO tracheostomy. Patients were monitored for complications. Procedure time was documented. A group of medical ICU patients had open tracheostomies in the operating room (OR) and served as contemporaneous controls. Over 11 months, there were 24 surgical ICU patients randomized to receive either BP tracheostomy or BO tracheostomy, 12 in each group. Forty-six medical ICU patients received standard open tracheostomy in the OR. The number of ventilator days before placing the tracheostomy was similar between the BP and BO groups, 9.8 and 12.4, respectively. The clinical indications for tracheostomy were similar between the two groups. The procedure time for the BP group was 14.5 minutes, whereas 25.2 minutes for the BO group. There were no postprocedure complications in the BP and BO groups. There was a trend toward more complications in the BP group, including the loss of the airway, leading to death. The procedure time and complications were similar between the BO and OR groups. These data do not support that BP tracheostomy is the preferred route of tracheostomy when compared with BO tracheostomy. These data support that experienced surgical intensivists can perform BO tracheostomies with lower risk and cost, when compared with BP tracheostomy.

The ACS is a clinical entity that develops from progressive, acute increases in IAP and affects multiple organ systems in a graded fashion because of differential susceptibilities. The gut is the organ most sensitive to IAH, and it develops evidence of end-organ damage before the development of the classic renal, pulmonary, and cardiovascular signs. Intracranial derangements with ACS are now well described. Treatment involves expedient decompression of the abdomen, without which the syndrome of end-organ damage and reduced oxygen delivery may lead to the development of multiple organ failure and, ultimately, death. Multiple trauma, massive hemorrhage, or protracted operation with massive volume resuscitation are the situations in which the ACS is most frequently encountered. Knowledge of the ACS, however, is also essential for the management of critically ill pediatric patients (especially those with AWD) and in understanding the limitations of laparoscopy. The role of IAH in the pathogenesis of NEC, central obesity co-morbidities, and pre-eclampsia/eclampsia remains to be fully studied.

Objective: To define the incidence, prophylaxis, and treatment of intra-abdominal hypertension (IAH) and its relevance to gut mucosal pH (pHi), multiorgan dysfunction syndrome, and the abdominal compartment syndrome (ACS)., Methods: Seventy patients in the SICU at a Level I trauma center (1992-1996) with life threatening penetrating abdominal trauma had intra-abdominal pressure estimated by bladder pressure. pHi was measured by gastric tonometry every 4 to 6 hours. IAH (intra-abdominal pressure> 25 cm of H2O) was treated by bedside or operating room laparotomy., Results: Injury severity was comparable between patients who had mesh closure as prophylaxis for IAH (n = 45) and those who had fascial suture (n = 25). IAH was seen in 10 (22.2%) in the mesh group versus 13 (52%) in the fascial suture group (p = 0.012) for an overall incidence of 32.9%. Forty-two patients had pHi monitoring, and 11 of them had IAH. Of the 11 patients, eight patients (72.7%) had acidotic pHi (7.10 +/- 0.2) with IAH without exhibiting the classic signs of ACS. The pHi improved after abdominal decompression in six and none developed ACS. Only two patients with IAH and low pHi went on to develop ACS, despite abdominal decompression. Multiorgan dysfunction syndrome points and death were less in patients without IAH than those with IAH and in patients who had mesh closure., Conclusions: IAH is frequent after major abdominal trauma. It may cause gut mucosal acidosis at lower bladder pressures, long before the onset of clinical ACS. Uncorrected, it may lead to splanchnic hypoperfusion, ACS, distant organ failure, and death. Prophylactic mesh closure of the abdomen may facilitate the prevention and bedside treatment of IAH and reduce these complications.

Complete resuscitation from shock is one of the primary concerns of the surgeon taking care of injured patients. Traditionally, the return to normalcy of blood pressure, heart rate, and urine output has been the end point of resuscitation. Using these end points may leave a substantial number of patients, up to 50 to 85% in some series, in "compensated" shock, which if it persists may ultimately lead to the death of the patient. Because of this potential other end points are being used and include supernormal values for oxygen transport variables (cardiac index, oxygen delivery, and oxygen consumption), lactate, base deficit, and gastric intramucosal pH. We believe that the current data support the use of lactate, base deficit, and/or gastric intramucosal pH as the appropriate end points of resuscitation of trauma patients. The goal should be to correct one or all of three of these markers of tissue perfusion to normal within the initial 24 hours after injury.

Objective: To critically reevaluate the indications for fasciotomy in vascular trauma of the extremities., Design: Case-control study., Setting: Level I trauma center., Materials and Methods: One hundred sixty-three vascular injuries to the extremeties were analyzed. Fasciotomy as an adjunct to vascular repair was performed in 45 limbs (28%), based either on the nature of injury or measured compartment pressure of greater than 35 mm Hg., Main Outcome Measures: Need for fasciotomy or limb amputation., Results: Fasciotomy was performed for 29.5% of isolated arterial injuries, 15.2% of isolated venous injuries, and 31.6% of combined arterial and venous injuries, and was not related to venous repair or ligation. Seven delayed fasciotomies were performed either for vascular repair failure (5 patients) or compartment syndrome (2 patients). The highest incidence was for popliteal vessel injury (arterial 57%, combined 61%). Of the 33 lower-extremity fasciotomies, 58% were for popliteal vessel injury. In 51 combined injuries of the lower extremity, only 7 (19%) of 38 patients with injury above the knee required fasciotomy, as compared with 8 (62%) of 13 with injury to the popliteal vessels (P<.001), with or without venous repair. There were 3 amputations, all resulting from vascular repair failure., Conclusions: The presence of a combined vascular injury or the need for venous ligation does not necessitate routine fasciotomy. The need for fasciotomy may be maximal for injuries to popliteal vessels.

IAH causes multiple and profound physiologic abnormalities both within and outside the abdomen. IAP monitoring is easily performed by bladder measurements. Careful monitoring and prompt recognition and treatment of IAP are critical in patients after damage control surgery because IAH is extremely common in these patients. Use of mesh fascial prostheses at the initial celiotomy in high-risk patients may prevent the deleterious effects of IAH. IAH should be considered an earlier manifestation of ACS. Surgical intervention should be indicated by IAH and not delayed until ACS is clinically apparent.

Background and Methods: Recent reports have documented a reduced mortality from injuries to the inferior vena cava (IVC). Few reports, however, have addressed the follow-up of the repaired IVC. From January of 1984 to December of 1995, we prospectively collected data on all patients with IVC injuries at Lincoln Medical and Mental Health Center, an urban Level I trauma center., Results: There were 81 patients with IVC injuries: 60 gunshot wounds, 17 stab wounds, and four blunt injuries. Overall, 45 patients survived (56%). Excluding those who arrived without vital signs and those who did not have emergency department thoracotomies, the survival was 68%. Of the survivors, 38 patients received lateral venorrhaphy, and seven patients underwent ligation. Of the 38 survivors with lateral venorrhaphy, 30 patients (79%) underwent noninvasive follow-up: 13 patients by sonography, 11 patients by computed tomographic scan, and six patients by both modalities. The IVC was visualized in 28 patients (93%) and was found to be patent in 24 (86%). There were four thromboses documented noninvasively, with three cases being confirmed by contrast venorrhaphy. All three resolved with systemic anticoagulation., Conclusions: We conclude that sonography and computed tomographic scan provide reliable noninvasive evaluation of the repaired IVC. We recommend that all patients with an IVC injury, which has been repaired, undergo evaluation for patency before discharge.

Background: Considerable skepticism still exists about the role of diagnostic laparoscopy in the evaluation of penetrating abdominal trauma. The reported experience with therapeutic laparoscopy has been limited., Methods: Retrospective analysis of a collective experience from three large urban trauma centers with 510 patients (316 stab wounds, 194 gunshot wounds) who were hemodynamically stable and had no urgent indications for celiotomy., Results: Laparotomy was avoided in 277 of the 510 patients (54.3%) either because of nonpenetration or insignificant findings on laparoscopy. All were discharged uneventfully after a mean hospital stay of 1.7 days. Twenty-six had successful therapeutic procedures on laparoscopy (diaphragmatic repair in 16 patients, cholecystectomy in 1 patient, hepatic repair in 6 patients, and closure of gastrotomy in 3 patients) with uneventful recovery. In the remaining 203 patients, laparotomy was therapeutic in 155. Fifty-two patients had nontherapeutic celiotomy for exclusion of bowel injuries or as mandatory laparotomy for penetrating gunshot wounds (19.7%). The overall incidence of nontherapeutic laparotomy was 10.2%. Complications from laparoscopy were minimal (10 of 510) and minor., Conclusions: Laparoscopy has an important diagnostic role in stable patients with penetrating abdominal trauma. In carefully selected patients, therapeutic laparoscopy is practical, feasible, and offers all the advantages of minimally invasive surgery.

The stable patient with an occult cardiac injury can represent a diagnostic dilemma. The trauma surgeon must maintain a high index of suspicion for cardiac injury with precordial penetrating trauma. Herein are reported two cases of stable patients with penetrating precordial trauma who refused to lie supine because of difficulty breathing, preferring to sit upright, who eventually had positive pericardial windows and sternotomies for repair of cardiac injuries. The presence of this clinical finding, unwillingness to lie supine, should make the trauma surgeon highly suspicious of a cardiac injury and to proceed quickly to echocardiography or, preferably, to subxiphoid pericardial window to rule out cardiac injury.

A case report and review of the exaggerated lithotomy position, in particular, and other position-related rhabdomyolysis is presented. The objective is to emphasize that the exaggerated lithotomy position, although providing good exposure for urethral and prostatic surgery, is associated with a low but definite risk of rhabdomyolysis and acute renal failure. Certain risk factors for the complication have been outlined. Close perioperative monitoring, including the use of pulmonary artery pressure and lower-extremity compartment pressure measurements in high-risk cases, is suggested for the prevention and the early detection of these cases. Prompt volume replacement and diuresis is the cornerstone of therapy in preventing acute renal failure in patients who develop rhabdomyolysis and myoglobinuria.