Edward E. Cornwell

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.

Evaluation of Penetrating Injuries of the Neck: Prospective Study of 223 Patients

Abstract. The objective of this study was to assess the role of clinical examination, angiography, color flow Doppler imaging, and other diagnostic tests in identifying injuries to the vascular or aerodigestive structures in patients with penetrating injuries to the neck. A prospective study was made of patients with penetrating neck injuries. All patients had a careful physical examination according to a written protocol. Stable patients underwent routine four-vessel angiography and color flow Doppler imaging. Esophagography and endoscopy were performed for proximity injuries. The sensitivity, specificity, and predictive values of physical examination, color flow Doppler studies, and other diagnostic tests were assessed during the evaluation of vascular and aerodigestive tract structures in the neck. Altogether 223 patients were entered in the study. After physical examination 176 patients underwent angiography and 99 of them underwent color flow Doppler imaging. Angiographic abnormalities were seen in 34 patients for an incidence of 19.3%, but only 14 (8.0%) required treatment. Color flow Doppler imaging was performed on 99 patients with a sensitivity of 91.7%, specificity 100%, positive predictive value (PPV) 100%, and negative predictive value (NPV) 99%. These values were all 100% when only injuries requiring treatment were considered. None of the 160 patients without clinical signs of vascular injury had serious vascular trauma requiring treatment (NPV 100%), although angiography in 127 showed 11 vascular lesions not requiring treatment. “Hard” signs on clinical examination (large expanding hematomas, severe active bleeding, shock not responding to fluids, diminished radial pulse, bruit) reliably predicted major vascular trauma requiring treatment. Among 34 of the 223 total patients (15.2%) admitted with “soft” signs, 8 had angiographically detected injuries, but only one required treatment. An esophagogram was performed on 98 patients because of proximity injuries (49 patients) or suspicious clinical signs (49 patients), and two of them showed esophageal perforations. None of the 167 patients without clinical signs of esophageal trauma had an esophageal injury requiring treatment. It was concluded that physical examination is reliable for identifying those patients with penetrating injuries of the neck who require vascular or esophageal diagnostic studies. Color flow Doppler imaging is a dependable alternative to angiography. An algorithm for the initial assessment of neck injuries is suggested.

Endpoints of resuscitation of critically injured patients: normal or supranormal? A prospective randomized trial.

ObjectiveTo evaluate the effect of early optimization in the survival of severely injured patients. Summary Background DataIt is unclear whether supranormal (“optimal”) hemodynamic values should serve as endpoints of resuscitation or simply as markers of the physiologic reserve of critically injured patients. The failure of optimization to produce improved survival in some randomized controlled trials may be associated with delays in starting the attempt to reach optimal goals. There are limited controlled data on trauma patients. MethodsSeventy-five consecutive severely injured patients with shock resulting from bleeding and without major intracranial or spinal cord trauma were randomized to resuscitation, starting immediately after admission, to either normal values of systolic blood pressure, urine output, base deficit, hemoglobin, and cardiac index (control group, 35 patients) or optimal values (cardiac index >4.5 L/min/m2, ratio of transcutaneous oxygen tension to fractional inspired oxygen >200, oxygen delivery index >600 mL/min/m2, and oxygen consumption index >170 mL/min/m2; optimal group, 40 patients). Initial cardiac output monitoring was done noninvasively by bioimpedance and, subsequently, invasively by thermodilution. Crystalloids, colloids, blood, inotropes, and vasopressors were used by predetermined algorithms. ResultsOptimal values were reached intentionally by 70% of the optimal patients and spontaneously by 40% of the control patients. There was no difference in rates of death (15% optimal vs. 11% control), organ failure, sepsis, or the length of intensive care unit or hospital stay between the two groups. Patients from both groups who achieved optimal values had better outcomes than patients who did not. The death rate was 0% among patients who achieved optimal values compared with 30% among patients who did not. Age younger than 40 years was the only independent predictive factor of the ability to reach optimal values. ConclusionsSeverely injured patients who can achieve optimal hemodynamic values are more likely to survive than those who cannot, regardless of the resuscitation technique. In this study, attempts at early optimization did not improve the outcome of the examined subgroup of severely injured patients.

Penetrating Cardiac Injuries: A Prospective Study of Variables Predicting Outcomes

BACKGROUND Penetrating cardiac injuries are one of the leading causes of death from urban violence. STUDY DESIGN This is a prospective, 1-year study in a Level I Trauma Center with the objective of analyzing: (1) the parameters measuring the physiologic condition of patients sustaining penetrating cardiac injuries in the field during transport and on arrival, (2) the cardiovascular-respiratory score (CVRS) component of the trauma score, (3) the mechanism and anatomic site of injury, (4) the presence or absence of tamponade, and (5) the cardiac rhythm as a predictor of outcomes. We attempted to correlate cardiac injury grade (AAST-OIS) with mortality. Our main intervention was thoracotomy for resuscitation and definitive repair of cardiac injury. Main outcomes measures were all parameters measuring the physiologic condition of patients, CVRS, mechanism and anatomic site of injury, operative findings and maneuvers, mortality, and grade of injury. RESULTS The study consisted of 60 patients sustaining penetrating cardiac injuries, 35 gunshot wound (58%) and 25 stab wounds (42%). The injury severity score (ISS) was > 30 in 22 patients; overall survival was 22 of 60 (36.6%); gunshot wound (GSW) survival, 5 of 35 (14%); and stab wound (SW) survival, 17 of 25 (68%). An emergency department thoracotomy was performed in 37 of 60 (61.7%) with 6 of 37 survivors (16%). CVRS: 96% mortality (25 of 26) when CVRS = 0; 67% mortality (6 of 9) when CVRS = 1-3; and 25% mortality (7 of 25) when CVRS > 4 (p < 0.001). Mechanism of injury, and presence of sinus rhythm when pericardium opened predict outcomes (p < 0.001). Anatomic site of injury and tamponade do not predict outcomes (not significant). AAST-OIS injury grade and mortality: grade IV, 31 of 60 (52%); grade V, 20 of 60 (75%), and grade VI, 6 of 60 (100%). CONCLUSIONS Parameters measuring physiologic condition, CVRS, and mechanism of injury plus initial rhythm are significant predictors of outcomes in penetrating cardiac injuries. The need for aortic crossclamping and the inability to restore an organized rhythm or blood pressure after thoracotomy were also predictors of outcomes. The presence of pericardial tamponade was not.

Undertriage of elderly trauma patients to state-designated trauma centers.

OBJECTIVE To determine whether age bias is a factor in triage errors. DESIGN Retrospective analysis of 10 years (1995-2004) of prospectively collected data in the statewide Maryland Ambulance Information System followed by surveys of emergency medical services (EMS) and trauma center personnel at regional EMS conferences and level I trauma centers, respectively. PATIENTS Trauma patients were defined as those who met American College of Surgeons physiology, injury, and/or mechanism criteria and were subjectively declared priority I status by EMS personnel. MAIN OUTCOME MEASURE Undertriage, defined as when trauma patients were not transported to a state-designated trauma center. RESULTS The registry analysis identified 26 565 trauma patients. The undertriage rate was significantly higher in patients aged 65 years or older than in younger patients (49.9% vs 17.8%, P < .001). On multivariate analysis, this decrease in trauma center transports was found to start at age 50 years (odds ratio, 0.67; 95% confidence interval, 0.57-0.77), with another decrease at age 70 years (odds ratio, 0.45; 95% confidence interval, 0.39-0.53) compared with patients younger than 50 years. A total of 166 respondents participated in the follow-up surveys and ranked the top 3 causal factors for this undertriage as inadequate training, unfamiliarity with protocol, and possible age bias. CONCLUSIONS Even when trauma is recognized and acknowledged by EMS, providers are consistently less likely to consider transporting elderly patients to a trauma center. Unconscious age bias, in both EMS in the field and receiving trauma center personnel, was identified as a possible cause.

Occult injuries to the diaphragm: prospective evaluation of laparoscopy in penetrating injuries to the left lower chest

Abstract Background: To evaluate the incidence of occult diaphragmatic injuries and investigate the role of laparoscopy in patients with penetrating trauma to the left lower chest who lack indications for exploratory celiotomy other than the potential for a diaphragm injury. Study Design: Patients with penetrating injuries to the left lower chest who were hemodynamically stable and without indications for a celiotomy were prospectively evaluated with diagnostic laparoscopy to determine the presence of an injury to the left hemidiaphragm. Diagnostic laparoscopy was performed in the operating room under general anesthesia. Results: One-hundred-ten patients (94 stab wounds, 16 gunshot wounds) were evaluated with laparoscopy. Twenty-six (24%) diaphragmatic injuries were identified (26% for stab wounds and 13% for gunshot wounds). Comparison of patients with diaphragmatic injuries with those without diaphragmatic injuries demonstrated a slightly greater incidence of hemo/pneumothoraces (35% versus 24%, NS). The incidence of diaphragmatic injuries in patients with a normal chest x-ray was 21% versus 31% for patients with a hemo/pneumothorax. An elevated left hemidiaphragm was associated with a diaphragmatic injuries in only 1 of 7 patients (14%). The incidence of diaphragmatic injuries was similar for anterior, lateral, and posterior injuries (22%, 27%, and 22% respectively). Conclusions: The incidence of occult diaphragmatic injuries in penetrating trauma to the left lower chest is high, 24%. These injuries are associated with a lack of clinical and radiographic findings, and would have been missed had laparoscopy not been performed. Patients with penetrating trauma to the left lower chest who do not have any other indication for a celiotomy should undergo videoscopic evaluation of the left hemidiaphragm to exclude an occult injury.

Inability of an aggressive policy of thromboprophylaxis to prevent deep venous thrombosis (dvt) in critically injured patients: are current methods of dvt prophylaxis insufficient?

BACKGROUND Deep venous thrombosis (DVT) in severely injured patients is a life-threatening complication. Effective and safe thromboprophylaxis is highly desirable to prevent DVT. Low-dose heparin (LDH) and sequential compression device (SCDs) are the most frequently used methods. Inappropriate use of these methods because of the nature or site of critical injuries (eg, brain lesion, solid visceral or retroperitoneal hematoma, extremity fractures) may lead to failure of DVT prophylaxis. STUDY DESIGN A prospective study was performed to evaluate the efficacy of a policy of aggressive use of LDH and SCDs in patients who are at very high risk for DVT. From January 1996 to August 1997, 200 critically injured patients were followed by weekly Doppler examinations to detect DVT at the proximal lower extremities. Only 3 patients did not receive any thromboprophylaxis. SCDs were applied in 97.5% and LDH was administered to 46% of the patients; 45% had both. RESULTS DVT was found in 26 patients (13%). The majority (58%) developed DVT within the first 2 weeks, but new cases were found as late as 12 weeks after admission. The incidence of DVT was the same among patients who had SCDs only or a combination of LDH and SCDs. Mechanism of injury, type and number of operations, site of injury, Injury Severity Score, and the incidence of femoral lines were not different between patients with and without DVT. Differences were found in the severity of injury to the chest and the extremities and the need for high-level respiratory support. Patients with DVT had prolonged ICU and hospital stays (on average, 34 and 49 days, respectively) and a high mortality rate (31%). CONCLUSIONS The incidence of DVT remains high among severely injured patients despite aggressive thromboprophylaxis. A combination of LDH and an SCD showed no advantage over SCD alone in decreasing DVT rates. Risk factors in this group of patients who are already at very high risk are hard to detect; Doppler examinations are justified for surveillance in all critically injured patients. Current methods of thromboprophylaxis seem to offer limited efficacy, and the search for more effective methods should continue.

Surveillance bias and deep vein thrombosis in the national trauma data bank: the more we look, the more we find.

BACKGROUND Deep vein thrombosis (DVT) has been identified as a marker of quality of care by various governmental and consumer groups. However, the lack of standardized DVT screening systems across trauma centers may introduce surveillance bias in the rates of DVT reported. We hypothesize that trauma centers with higher rates of duplex ultrasound detect more DVTs and subsequently report higher DVT rates to the National Trauma Data Bank. METHODS We queried the National Trauma Data Bank version 6.1 and calculated ultrasound rates and DVT rates per trauma center. We excluded hospitals that did not report performing any ultrasounds or any complications. Simple and multiple linear regressions were used to describe the association between ultrasound and DVT rates among hospitals. RESULTS One hundred forty-seven hospitals (16%) met the inclusion criteria, accounting for 578,252 patients (39% of the total patients in the dataset). When dividing hospitals into quartiles by duplex ultrasound rate, the DVT rate in the highest quartile was 7-fold higher than the average combined DVT rate in the first three quartiles (1.52% vs. 0.22%; p < 0.001). Multivariable analysis suggested that hospitals with an ultrasound rate </=2% had a 1.07% increase in reported DVT rate for every 1% increase in ultrasound rate (95% confidence interval 1.05-1.09; p < 0.001). CONCLUSIONS More aggressive screening procedures may be associated with higher DVT rates. Trauma centers that screen more and report higher DVT rates may be falsely labeled as having decreased quality of care. Using DVT rate alone as an independent quality measure should be reevaluated because of the potential for surveillance bias.

Spine immobilization in penetrating trauma: more harm than good?

BACKGROUND Previous studies have suggested that prehospital spine immobilization provides minimal benefit to penetrating trauma patients but takes valuable time, potentially delaying definitive trauma care. We hypothesized that penetrating trauma patients who are spine immobilized before transport have higher mortality than nonimmobilized patients. METHODS We performed a retrospective analysis of penetrating trauma patients in the National Trauma Data Bank (version 6.2). Multiple logistic regression was used with mortality as the primary outcome measure. We compared patients with versus without prehospital spine immobilization, using patient demographics, mechanism (stab vs. gunshot), physiologic and anatomic injury severity, and other prehospital procedures as covariates. Subset analysis was performed based on Injury Severity Score category, mechanism, and blood pressure. We calculated a number needed to treat and number needed to harm for spine immobilization. RESULTS In total, 45,284 penetrating trauma patients were studied; 4.3% of whom underwent spine immobilization. Overall mortality was 8.1%. Unadjusted mortality was twice as high in spine-immobilized patients (14.7% vs. 7.2%, p < 0.001). The odds ratio of death for spine-immobilized patients was 2.06 (95% CI: 1.35-3.13) compared with nonimmobilized patients. Subset analysis showed consistent trends in all populations. Only 30 (0.01%) patients had incomplete spinal cord injury and underwent operative spine fixation. The number needed to treat with spine immobilization to potentially benefit one patient was 1,032. The number needed to harm with spine immobilization to potentially contribute to one death was 66. CONCLUSIONS Prehospital spine immobilization is associated with higher mortality in penetrating trauma and should not be routinely used in every patient with penetrating trauma.

Prevalence and types of sleep disturbances acutely after traumatic brain injury

Primary objective: To assess the prevalence of and risk factors for sleep disturbances in the acute post-traumatic brain injury (TBI) period. Research design: Longitudinal, observational study. Methods and procedures: Fifty-four first time closed-head injury patients were recruited and evaluated within 3 months after injury. Pre-injury and post-injury sleep disturbances were compared on the Medical Outcome Scale for Sleep. The subjects were also assessed on anxiety, depression, medical comorbidity and severity of TBI. Main outcomes and results: Subjects were worse on most sleep measures after TBI compared to before TBI. Anxiety disorder secondary to TBI was the most consistent significant risk factor to be associated with worsening sleep status. Conclusions: Anxiety is associated with sleep disturbances after TBI. Further studies need to be done to evaluate if this is a causal relationship.