Michael H. Thomason

Prospective Study of Blunt Aortic Injury: Multicenter Trial of the American Association for the Surgery of Trauma

BACKGROUND Blunt aortic injury is a major cause of death from blunt trauma. Evolution of diagnostic techniques and methods of operative repair have altered the management and posed new questions in recent years. METHODS This study was a prospectively conducted multi-center trial involving 50 trauma centers in North America under the direction of the Multi-institutional Trial Committee of the American Association for the Surgery of Trauma. RESULTS There were 274 blunt aortic injury cases studied over 2.5 years, of which 81% were caused by automobile crashes. Chest computed tomography and transesophageal echocardiography were applied in 88 and 30 cases, respectively, and were 75 and 80% diagnostic, respectively. Two hundred seven stable patients underwent planned thoracotomy and repair. Clamp and sew technique was used in 73 (35%) and bypass techniques in 134 (65%). Overall mortality was 31%, with 63% of deaths being attributable to aortic rupture; mortality was not affected by method of repair. Paraplegia occurred postoperatively in 8.7%. Logistic regression analysis demonstrated clamp and sew (p = 0.002) and aortic cross clamp time of > or = 30 minutes (p = 0.01) to be associated with development of postoperative paraplegia. CONCLUSIONS Rupture after hospital admission remains a major problem. Although newer diagnostic techniques are being applied, at this time aortography remains the diagnostic standard. Aortic cross clamp time beyond 30 minutes was associated with paraplegia; bypass techniques, which provide distal aortic perfusion, produced significantly lower paraplegia rates than the clamp and sew approach.

Penetrating colon injuries requiring resection: Diversion or primary anastomosis? An AAST prospective multicenter study

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.

Thoracic Aorta Injuries: Management and Outcome of 144 Patients

Rupture of the thoracic aorta from blunt injury is often lethal. Methods of operative repair vary, based on the surgeons preference and circumstances. The primary hypothesis of this study was that operative management choices would correlate with outcome. Data on demographics, injury mechanism, initial evaluation, diagnostic procedures, operative treatment, and outcome were obtained from chart review at the states eight trauma centers. Rates of paraplegia and survival were compared for different methods of operative repair. Of 63,507 hospitalized trauma patients, 144 patients sustained thoracic aortic injury (incidence = 0.23%). Sixty-four died (44.1%), most of whom died in the emergency department (26) or the operating room (12). Eighty-six patients had complete operative data for analysis, including cross-clamp time and methods of repair. No patient in the group with a cross-clamp time of less than 35 minutes developed paraplegia (p = 0.02). For the patients with longer cross-clamp times, 6 of 14 patients (42.9%) undergoing clamp and sew repair developed paraplegia, as compared to 2 of 37 patients (5.4%) repaired on bypass (p = 0.005). This study suggests that the rate of paraplegia after repair of thoracic aortic injury can be minimized with short cross-clamp times or the use of bypass when long cross-clamp times can be anticipated.

FAST (Focused Assessment With Sonography in Trauma) Accurate for Cardiac and Intraperitoneal Injury in Penetrating Anterior Chest Trauma

Objective. To evaluate the FAST (focused assessment with sonography in trauma) examination for determining traumatic pericardial effusion and intraperitoneal fluid indicative of injury in patients with penetrating anterior chest trauma. Methods. An observational prospective study was conducted over a 30‐month period at an urban level I trauma center. FAST was performed in the emergency department by emergency physicians and trauma surgeons. FAST results were recorded before review of patient outcome as determined by 1 or more of the following: thoracotomy, laparotomy, pericardial window, cardiologic echocardiography, diagnostic peritoneal lavage, computed tomography, and serial examinations. Results. FAST was undertaken in 32 patients with penetrating anterior chest trauma: 20 (65%) had stab wounds, and 12 (35%) had gunshot wounds. Sensitivity of FAST for cardiac injury (n = 8) in patients with pericardial effusion was 100% (95% confidence interval, 63.1%–100%); specificity was 100% (95% confidence interval, 85.8%–100%). The presence of pericardial effusion determined by FAST correlated with the need for thoracotomy in 7 (87.5%) of 8 patients (95% confidence interval, 47.3%–99.7%). One patient with a pericardial blood clot on cardiologic echocardiography was treated nonsurgically. FAST had 100% sensitivity for intraperitoneal injury (95% confidence interval, 63.1%–100%) in 8 patients with views indicating intraperitoneal fluid but without pericardial effusion, again with no false‐positive results, giving a specificity of 100% (95% confidence interval, 85.8%–100%). This prompted necessary laparotomy in all 8. Conclusions. In this series of patients with penetrating anterior chest trauma, the FAST examination was sensitive and specific in the determination of both traumatic pericardial effusion and intraperitoneal fluid indicative of injury, thus effectively guiding emergent surgical decision making.

The spectrum of abdominal injuries associated with the use of seat belts

Several recent reports have described abdominal injuries occurring as a result of seat belt use, raising concerns about seat belts as an agent of injury in motor vehicle crashes. The purpose of this study was to characterize the distribution of abdominal injuries after motor vehicle crashes in belted and unbelted patients admitted to trauma centers. The mortality was higher in unbelted than belted patients (7% vs. 3.2%, respectively, p less than 0.0001). Unbelted patients also had significantly more frequent and more severe head injuries (50.0% vs. 32.9%, respectively, p less than 0.001). The incidence of abdominal injury was equal in both unbelted patients (13.9%), but the spectrum of organs injured was different in the two groups. Gastrointestinal tract injuries (stomach, small bowel, colon and rectum) were significantly more frequent in belted vs. unbelted patients (3.4% vs. 1.8%, respectively, p = 0.001). The frequency of liver and spleen injuries was the same in both groups. This study demonstrates that in patients admitted to trauma centers after motor vehicle crashes, belted and unbelted patients have an equal incidence of abdominal injury, but belted and unbelted patients have a different spectrum of injuries. Hollow viscus injuries are more common in belted crash victims. Seat belt use was associated with significantly fewer head injuries and deaths. Physicians evaluating trauma victims after motor vehicle crashes should be aware of the fact that the types of abdominal injuries may vary substantially depending on seat belt use.

Handsewn versus stapled anastomosis in penetrating colon injuries requiring resection: a multicenter study.

BACKGROUND Although the use of stapling devices in elective colon surgery has been shown to be as safe as handsewn techniques, there have been concerns about their safety in emergency trauma surgery. The purpose of this study was to compare stapled with handsewn colonic anastomosis following penetrating trauma. METHODS This was a prospective multicenter study and included patients who underwent colon resection and anastomosis following penetrating trauma. Multivariate logistic regression analysis was used to identify independent risk factors for abdominal complications and compare outcomes between stapled and handsewn repairs. RESULTS Two hundred seven patients underwent colon resection and primary anastomosis. In 128 patients (61.8%) the anastomosis was performed with handsewing and in the remaining 79 (38.2%) with stapling devices. There were no colon-related deaths and the overall incidence of colon-related abdominal complications was 22.7% (26.6% in the stapled group and 20.3% in the handsewn group, p = 0.30). The incidence of anastomotic leak was 6.3% in the stapled group and 7.8% in the handsewn group (p = 0.69). Multivariate analysis adjusting for blood transfusions, fecal contamination, and type of antibiotic prophylaxis showed that the adjusted odds ratio (OR) of complications in the stapled group was 0.83 (95% CI, 0.38-1.74, p = 0.63). In a second multivariate analysis adjusting for blood transfusions, hypotension, fecal contamination, Penetrating Abdominal Trauma Index, and preoperative delays the adjusted OR in the stapled group was 0.99 (95% CI, 0.46-2.11, p = 0.99). CONCLUSION The results of this study suggest that the method of anastomosis following colon resection for penetrating trauma does not affect the incidence of abdominal complications and the choice should be surgeons preference.

Validation of new trauma triage rules for trauma attending response to the emergency department.

INTRODUCTION The American College of Surgeons Committee on Trauma has suggested triage criteria for the immediate attendance of a trauma surgeon to an injured patient in the emergency department. This study validates the accuracy of these criteria in identifying high-risk trauma patients and assesses the impact of trauma surgeon response time. METHODS A study group of trauma patients with a systolic blood pressure (SBP) < 90 mm Hg, Glasgow Coma Scale (GCS) score < 8, airway compromise managed with endotracheal intubation (ETI) or surgical airway, or gunshot wound (GSW) to the neck or torso were compared with a control group of patients meeting none of these criteria. Outcome measurements included Injury Severity Score (ISS), duration of hospitalization (length of stay [LOS]), intensive care unit (ICU) days, direct transfer to the ICU or operating room, and mortality. For the study group, trauma surgeon response times, < or = 15 minutes and > 15 minutes, were compared for age, ISS, LOS, ICU days, mortality, and direct transfer to the ICU or operating room. Statistical analysis was performed using the t test and the Yates-corrected chi(2) test (p < 0.05), with odds ratios calculated on the basis of trauma activation criteria and outcome measures. Multiple logistic regression was used to assess the relation between the independent variables SBP, GCS, ETI, and GSW with direct transfer to the ICU or operating room and mortality. RESULTS A total of 4,910 patients were identified, including 791 study group patients. The mean ISS, LOS, ICU days, and mortality were significantly higher in the study group (p < 0.01). Odds ratios of the study group for direct transfer to the ICU or operating room were 91 and 2 for ETI, 23 and 1.4 for GCS score < 8, 8 and 2.2 for GSW, and 7 and 1.6 for SBP < 90 mm Hg, respectively. The odds ratios for mortality were 39 for ETI, 104 for GCS score < 8, 12 for GSW, and 74 for SBP < 90 mm Hg. Regression analysis demonstrated that GSW, SBP < 90 mm Hg, and ETI predicted ICU admission; GSW, SBP < 90 mm Hg, and ETI predicted operative intervention; and GCS score < 8, SBP < 90 mm Hg, and ETI were associated with mortality. Trauma surgeon response times were available for 658 (83%) of the study group patients. No significant differences were found between the two response groups. CONCLUSION Trauma patients meeting the triage criteria proposed by the American College of Surgeons Committee on Trauma have more severe injuries, a higher mortality rate, and longer hospital and ICU stays than control patients. SBP < 90 mm Hg, ETI, and GSW are predictive of urgent operating room use and ICU admission. A significantly higher mortality rate is associated with SBP < 90 mm Hg, ETI, and GCS score < 8. Incorporating these criteria into trauma center triage rules to identify high-risk injured patients is warranted. However, trauma surgeon response time < or = 15 minutes was not associated with improved patient outcome, and optimal response time remains uncertain.

Management outcomes in splenic injury: a statewide trauma center review

OBJECTIVE Clinical pathways now highlight both observation and operation as acceptable initial therapeutic options for the management of patients with splenic injury. The purpose of this study was to evaluate treatment trends for splenic injury in all North Carolina trauma centers over a 6-year period. METHODS Splenic injuries in adults over a 6-year period (January 1988-December 1993) were identified in the North Carolina Trauma Registry using ICD-9-CM codes. Patients were divided into four groups by method of management: 1) no spleen operation, 2) splenectomy, 3) definitive splenorrhaphy, and 4) splenorrhaphy failure followed by splenectomy. The authors examined age, mechanism of injury, admitting blood pressure, and severity of injury by trauma score and injury severity score. SUMMARY BACKGROUND DATA Comparisons were made between adult (17-64 years of age) and geriatric (older than 65 years of age) patients and between patients with blunt and penetrating injury. Resource utilization (length of stay, hospital charges) and outcome (mortality) were compared. RESULTS One thousand two hundred fifty-five patients were identified with splenic injury. Rate of splenic preservation increased over time and was achieved in more than 50% of patients through nonoperative management (40%) and splenorrhaphy (12%). Splenorrhaphy was not used commonly in either blunt or penetrating injury. Overall mortality was 13%. Geriatric patients had a higher mortality and resource utilization regardless of their mechanism of injury or method of management. CONCLUSIONS Nonoperative management represents the prevailing method of splenic preservation in both the adult and geriatric population in North Carolina trauma center hospitals. Satisfactory outcomes and economic advantages accompany nonoperative management in this adult population.

Value of point-of-care blood testing in emergent trauma management.

BACKGROUND No prospective study demonstrates the value of point-of-care laboratory testing (POCT) in the management of major trauma. METHODS In a prospective, noninterventional, study of 200 major trauma patients, we evaluated the influence of a blood POCT profile (hemoglobin, Na+, K+, Cl-, blood urea nitrogen, glucose, pH, PCO2, PO2, HCO3-, base deficit, and lactate) on emergent diagnostic and therapeutic interventions. Physicians responded to a standardized set of questions on their diagnostic and therapeutic plans before and after the availability of POCT results. Management plan changes were deemed emergently appropriate, if they were influenced by the POCT results and, within the ensuing 30 minutes, the change in management was likely to reduce morbidity or conserve resources. RESULTS For emergently appropriate plan changes, Na+, Cl-, K+, and blood urea nitrogen were never influential, whereas in each of 6.0% of cases (95% confidence interval [CI], 3.5%-10.2%) at least one of the remaining POCT parameters was influential. An emergently appropriate change was based on hemoglobin in 3.5% of cases (95% CI, 1.0%-6.1%), blood gas parameters in 3.0% of cases (95% CI, 0.64%-5.7%), lactate in 2.5% of cases (95% CI, 1.1%-5.7%), and glucose in 0.5% of cases (95% CI, 0.1%-2.8%). All of these cases involved blunt injury. CONCLUSION Na+, Cl-, K+, and blood urea nitrogen levels do not influence the initial management of major trauma patients. In patients with severe blunt injury, hemoglobin, glucose, blood gas, and lactate measurements occasionally result in morbidity-reducing or resource-conserving management changes.

Comparison of the ability of adult and pediatric trauma scores to predict pediatric outcome following major trauma

The Pediatric Trauma Score (PTS) has been identified as the only accurate and adequate means of predicting outcome in pediatric trauma. In answer to the increasing number of trauma patients arriving at local hospitals, the ability of the adult Trauma Score (TS) to predict pediatric trauma outcome was tested. Of the total 2,604 pediatric trauma cases in the North Carolina State Trauma Registry, 441 had both a PTS and TS available for analysis. The primary measures of outcome were emergency department and hospital dispositions. Logistic regression demonstrated that TS (R2 = 0.50) was a stronger predictor of pediatric outcome and PTS (R2 = 0.35) for emergency department disposition and TS (R2 = 0.63) with PTS (R2 = 0.51) for hospital disposition. The correlation between TS and PTS was high (R = 0.8). Stepwise discriminant analysis demonstrated that TS was the stronger predictor of outcome and the PTS added only 9% (partial R2 = 0.09) more accuracy to TS for emergency department disposition and only 6% (partial R2 = 0.06) for hospital disposition. The results of this research demonstrate that TS is a useful method of predicting outcome in pediatric trauma. The use of both scores for each patient does not increase the predictive value of the scores.