Heidi L. Frankel

Penetrating esophageal injuries: Multicenter study of the American Association for the Surgery of Trauma

OBJECTIVE The purpose of this study was to define the period of time after which delays in management incurred by investigations cause increased morbidity and mortality. The outcome study is intended to correlate time with death from esophageal causes, overall complications, esophageal related complications, and surgical intensive care unit length of stay. METHODS This was a retrospective multicenter study involving 34 trauma centers in the United States, under the auspices of the American Association for the Surgery of Trauma Multi-institutional Trials Committee over a span of 10.5 years. Patients surviving to reach the operating room (OR) were divided into two groups: those that underwent diagnostic studies to identify their injuries (preoperative evaluation group) and those that went immediately to the OR (no preoperative evaluation group). Statistical methods included Fishers exact test, Students T test, and logistic regression analysis. RESULTS The study involved 405 patients: 355 male patients (86.5%) and 50 female patients (13.5%). The mean Revised Trauma Score was 6.3, the mean Injury Severity Score was 28, and the mean time interval to the OR was 6.5 hours. There were associated injuries in 356 patients (88%), and an overall complication rate of 53.5%. Overall mortality was 78 of 405 (19%). Three hundred forty-six patients survived to reach the OR: 171 in the preoperative evaluation group and 175 in the no preoperative evaluation group. No statistically significant differences were noted in the two groups in the following parameters: number of patients, age, Injury Severity Score, admission blood pressure, anatomic location of injury (cervical or thoracic), surgical management (primary repair, resection and anastomosis, resection and diversion, flaps), number of associated injuries, and mortality. Average length of time to the OR was 13 hours in the preoperative evaluation group versus 1 hour in the no preoperative evaluation group (p < 0.001). Overall complications occurred in 134 in the preoperative evaluation group versus 87 in the no preoperative evaluation group (p < 0.001), and 74 (41%) esophageal related complications occurred in the preoperative evaluation group versus 32 (19%) in the no preoperative evaluation group (p = 0.003). Mean surgical intensive care unit length of stay was 11 days in the preoperative evaluation group versus 7 days in the no preoperative evaluation group (p = 0.012). Logistic regression analysis identified as independent risk factors for the development of esophageal related complications included time delays in preoperative evaluation (odds ratio, 3.13), American Association for the Surgery of Trauma Organ Injury Scale grade >2 (odds ratio, 2.62), and resection and diversion (odds ratio, 4.47). CONCLUSION Esophageal injuries carry a high morbidity and mortality. Increased esophageal related morbidity occurs with the diagnostic workup and its inherent delay in operative repair of these injuries. For centers practicing selective management of penetrating neck injuries and transmediastinal gunshot wounds, rapid diagnosis and definitive repair should be made a high priority.

Ethnic disparities in long-term functional outcomes after traumatic brain injury.

OBJECTIVE Ethnic disparities have been demonstrated in several diseases, but not in trauma. We hypothesized that access to acute rehabilitation and long-term functional outcomes among traumatic brain injury (TBI) patients are influenced by patient race and ethnicity. METHODS Patients with severe TBI (Abbreviated Injury Scale [AIS] score, 3-5) who were discharged alive from initial hospitalization were recruited from an urban Level I trauma center (1998-2005). Functional outcome was measured 6 to 12 months after injury using the Glasgow Outcome Scale-Extended (GOSE) score, and classified as good recovery (GOSE score, 7 and 8) or moderate to severe disability (GOSE score, 1-6). Ethnic minorities (n = 114) were compared with non-Hispanic Whites (NHW, n = 230). Logistic regression was used to measure the association between ethnicity and functional outcome while controlling for age, gender, Injury Severity Score (ISS), head AIS score, Glasgow Coma Scale (GCS) score, discharge disposition, and insurance. RESULTS Minority and NHW groups had similar ISS, GCS score, and head AIS score. Ethnic minorities were less likely to be insured (uninsured, 66% vs. 31%, p < 0.001), but were equally likely to be placed in a rehabilitation facility upon trauma center discharge (47% vs. 42%, p = 0.417). Minority patients were more likely to have moderate to severe disability at follow-up (74% vs. 61%; adjusted odds ratio [OR], 2.17; 95% confidence interval [CI], 1.27-3.69). The relationship between ethnicity and functional outcome became insignificant when insurance was taken into account (OR, 1.52; 95% CI, 0.81-2.72). CONCLUSION Despite equal access to acute rehabilitation, ethnic minorities have significantly worse long-term functional outcomes after TBI, which is related to lack of health insurance.

Early use of vasopressors after injury: caution before constriction.

OBJECTIVE Recent evidence suggests that overly aggressive crystalloid resuscitation is associated with poor outcome. This has led to a renewed interest in the use of vasopressors for hemodynamic support during resuscitation after injury. We sought to characterize early vasopressor (EV) use and aggressive early crystalloid resuscitation (ECR) and their association with mortality in severely injured patients. METHODS Data were obtained from a multicenter, prospective, cohort study designed to evaluate the outcome of blunt injured adults in hemorrhagic shock. Early deaths (<48 hours) were excluded from the analysis. A single Cox proportional hazard regression model was used to evaluate the effects of EV use (levophed, phenylephrine, dopamine, or vasopressin) and aggressive ECR on mortality at 12 and 24 hours postinjury, while controlling for important physiologic, injury, resuscitation, and patient demographic confounders. RESULTS Cox proportional hazard regression revealed that EV use within 12 hours after injury was independently associated with over an 80% higher risk of mortality (hazard ratio [HR] 1.81, 95% confidence interval [CI] 1.1-2.9, p = 0.013), and was independently associated with over a twofold higher risk of mortality at 24 hours (HR 2.15, 95% CI 1.4-3.4, p = 0.001). These findings were consistent across all vasopressor subtypes. Aggressive ECR was independently associated with a 40% reduction in mortality (HR 0.594, 95% CI 0.37-0.95, p = 0.030). CONCLUSION These findings provide evidence that the early use of vasopressors for hemodynamic support after hemorrhagic shock may be deleterious, and should be used cautiously and not in place of aggressive crystalloid resuscitation after severe blunt injury.

Accuracy of cardiac function and volume status estimates using the bedside echocardiographic assessment in trauma/critical care.

BACKGROUND Critically ill patients often require invasive monitoring to evaluate and optimize cardiac function and preload. With questionable outcomes associated with pulmonary artery catheters (PACs), some have evaluated the role of less invasive monitors. We hypothesized that the Bedside Echocardiographic Assessment in Trauma (BEAT) examination would generate cardiac index (CI) and central venous pressure (CVP) estimates that correlate with that of a PAC. METHODS BEAT was performed on all SICU patients with a PAC in place. Prospective data included stroke volume and the inferior vena cava (IVC) diameter. The CI was calculated and correlated with that from the PAC. Each CI was then categorized as low, normal, or high. The IVC diameter was used to estimate the CVP. The association between the BEAT and PAC estimates of CI and CVP was evaluated using chi. RESULTS Eighty-five BEAT examinations were performed, 57% on trauma and 37% on general surgery patients. Fifty-nine percent of the CI examinations and 97% of the IVC examinations contained quality images. Of these, the overall correlation coefficient was 0.70 (p < 0.0001). When CI was categorized, there was a significant association between the BEAT and PAC (p = 0.021). There was a significant association between the CVP estimate from the BEAT examination and the PAC (p = 0.031). CONCLUSION Our data show a significant correlation between the CI and CVP estimates obtained from the BEAT examination and that from a PAC. BEAT provides a noninvasive method of evaluating cardiac function and volume status. Bedside echocardiography is teachable and should become a part of future critical care curricula.

Changing epidemiology of trauma deaths leads to a bimodal distribution

Injury mortality was classically described with a trimodal distribution, with immediate deaths at the scene, early deaths due to hemorrhage, and late deaths from organ failure. We hypothesized that the development of trauma systems has improved prehospital care, early resuscitation, and critical care and altered this pattern. This population-based study of all trauma deaths in an urban county with a mature trauma system reviewed data for 678 patients (median age, 33 years; 81% male; 43% gunshot, 20% motor vehicle crashes). Deaths were classified as immediate (scene), early (in hospital, ≤4 hours from injury), or late (>4 hours after injury). Multinomial regression was used to identify independent predictors of immediate and early versus late deaths, adjusted for age, gender, race, intention, mechanism, toxicology, and cause of death. Results showed 416 (61%) immediate, 199 (29%) early, and 63 (10%) late deaths. Compared with the classical description, the percentage of immediate deaths remained unchanged, and early deaths occurred much earlier (median 52 vs 120 minutes). However, unlike the classic trimodal distribution, the late peak was greatly diminished. Intentional injuries, alcohol intoxication, asphyxia, and injuries to the head and chest were independent predictors of immediate death. Alcohol intoxication and injuries to the chest were predictors of early death, while pelvic fractures and blunt assaults were associated with late deaths. In conclusion, trauma deaths now have a predominantly bimodal distribution. Near elimination of the late peak likely represents advancements in resuscitation and critical care that have reduced organ failure. Further reductions in mortality will likely come from prevention of intentional injuries and injuries associated with alcohol intoxication.

Characterization of the gender dimorphism after injury and hemorrhagic shock: Are hormonal differences responsible?*

Objective:To characterize the gender dimorphism after injury with specific reference to the reproductive age of the women (young, <48 yrs of age, vs. old, >52 yrs of age) in a cohort of severely injured trauma patients for which significant variation in postinjury care is minimized. Design:Secondary data analysis of an ongoing prospective multicenter cohort study. Setting:Academic, level I trauma and intensive care unit centers. Patients:Blunt-injured adults with hemorrhagic shock. Interventions:None. Measurements and Main Results:Separate Cox proportional hazard regression models were formulated based on all patients to evaluate the effects of gender on mortality, multiple organ failure, and nosocomial infection, after controlling for all important confounders. These models were then used to characterize the effect of gender in young and old age groups. Overall mortality, multiple organ failure, and nosocomial infection rates for the entire cohort (n = 1,036) were 20%, 40%, and 45%, respectively. Mean Injury Severity Score was 32 ± 14 (mean ± sd). Men (n = 680) and women (n = 356) were clinically similar except that men required higher crystalloid volumes, more often had a history of alcoholism and liver disease, and had greater ventilatory and intensive care unit requirements. Female gender was independently associated with a 43% and 23% lower risk of multiple organ failure and nosocomial infection, respectively. Gender remained an independent risk factor in young and old subgroup analysis, with the protection afforded by female gender remaining unchanged. Conclusions:The independent protective effect of female gender on multiple organ failure and nosocomial infection rates remains significant in both premenopausal and postmenopausal women when compared with similarly aged men. This is contrary to previous experimental studies and the known physiologic sex hormone changes that occur after menopause in women. These results suggest that factors other than sex hormones may be responsible for gender-based differences after injury.

Determining anatomic injury with computed tomography in selected torso gunshot wounds.

BACKGROUND Changes in the management of torso gunshot wounds (TGSWs) have evolved in recent years as a result of differences between military and civilian injuries and increasing interest in avoiding nontherapeutic invasive procedures. The objective of this study was to establish the utility and accuracy of computed tomography (CT) in the evaluation of selected patients with TGSWs. METHODS Retrospective review for a 6-year period of patients who sustained TGSWs and underwent CT solely for the purpose of trajectory determination. Patients had complete physical examinations and plain radiographic evaluations by a dedicated group of in-house trauma surgeons. When trajectory was indeterminate after evaluation, CT was performed. In some cases, CT was used when trajectory was determined to be intracavitary but organ injury was believed to be unlikely or amenable to nonoperative management. RESULTS Fifty TGSW patients underwent 52 computed tomographic scans. Abdominal/pelvic CT was performed in 37 patients, and thoracic CT was performed in 15 patients. All patients were stable and none sustained complications attributable to CT or delay in therapy. Twenty of 37 abdominal/pelvic computed tomographic scans excluded transabdominal or pelvic trajectory. Seventeen of 37 scans proved transabdominal or pelvic trajectory; nine laparotomies were performed, and eight patients were observed. Nine of 15 thoracic computed tomographic scans excluded transmediastinal trajectory. Six of 15 scans suggested vascular proximity and prompted further workup, which was positive in two cases. CONCLUSION CT of selected TGSW patients is safe and may reduce the incidence of invasive diagnostic procedures. A prospective evaluation of CT for TGSW patients is warranted.

Male gender is associated with excessive IL-6 expression following severe injury

OBJECTIVE An important and persistent laboratory finding has been that males and females respond differently after traumatic injury and hemorrhagic shock. We have previously presented clinical data showing that male gender is independently associated with a 40% higher rate of multiple organ failure (MOF) and a 25% higher rate of nosocomial infection (NI) after injury; however, the mechanism responsible for this dimorphic response after injury has not been adequately characterized clinically. METHODS Data were obtained from a multicenter prospective cohort study evaluating clinical outcomes in severely injured adults with blunt hemorrhagic shock. Proteomic analysis of serum inflammatory cytokines, on days 0, 1, and 4 postinjury, was performed on 46 males and 34 females. Repeated measures ANOVA were used to compare serial IL-1beta, TNF-alpha, IL-6, IL-8, and IL-10 serum levels across gender, while controlling for important confounders. Logistic regression modeling was then used to analyze the independent risk of MOF and NI associated with gender. RESULTS IL-6 serum levels were statistically higher in males relative to females (p = 0.008). This higher level of IL-6 expression in males remained statistically significant over time even after controlling for differences in age, initial base deficit, ISS, and 12-hour blood transfusion requirements (p = 0.025). No differences in IL-1beta serum levels (p = 0.543), TNF-alpha, (p = 0.200) IL-8 (p = 0.107), and IL-10 (p = 0.157) were found. Males had a higher crude incidence of MOF and an 11-fold higher independent risk of MOF. CONCLUSIONS Persistently elevated IL-6 levels in males are associated with a higher rate of MOF. It is not known if this excessive IL-6 expression in males is causal or only a marker for poor outcome. Further studies are required to elucidate if this early, persistent IL-6 expression is responsible for the gender-based differential outcomes after injury.

Peripherally Inserted Central Catheters May Lower the Incidence of Catheter-Related Blood Stream Infections in Patients in Surgical Intensive Care Units

BACKGROUND Long-term central venous catheterization is associated with a higher rate of catheter-related blood stream infections (CR-BSI). It is unclear whether there is a difference in the CR-BSI rate associated with central venous catheters (CVCs) and peripherally inserted central catheters (PICCs) in long-stay patients in surgical intensive care units (SICUs). We hypothesized that PICC use reduces the rate of CR-BSI compared with use of antiseptic CVCs in these patients. METHODS All 121 patients admitted to our SICU for ≥14 days between July 2005 and July 2006 were included. Central venous access was maintained with an antiseptic CVC (Arrow Guard silver/chlorhexidine; n = 263) or replacement with a PICC (n = 37). Experienced residents, using maximum barrier precautions and chlorhexidine skin preparation, placed central lines; a credentialed registered nurse placed PICCs similarly. A CR-BSI was defined by semi-quantitative catheter tip cultures with ≥15 colony-forming units and at least one positive blood culture with the same organism. Multivariable regression was performed to identify predictors of CR-BSI. RESULTS There were 13 CVC infections and one PICC infection, resulting in an infection rate of 6.0/1,000 catheter-days for CVCs and 2.2/1,000 for PICCs. Infected and non-infected CVCs were in place a mean of 25 ± 11 and 16 ± 9 days, respectively. The infected PICC was in place for 19 days, whereas the remainder of the PICCs were in place a mean of 14 ± 17 days. Logistic regression demonstrated that line days (duration of catheterization) was the only independent predictor of CVC infection (p = 0.015). CONCLUSION In this non-randomized study, PICC was associated with fewer CR-BSIs in long-stay SICU patients, although CVCs were in place longer than PICC lines. The only predictor of CVC infection was the duration the line was in place. These results suggest that minimizing the duration of central venous access and substituting PICC for CVC may reduce the incidence of CR-BSI in long-stay SICU patients.

Diaspirin cross-linked hemoglobin is efficacious in gut resuscitation as measured by a GI tract optode.

The objective of this study was to compare the efficacy of diaspirin cross-linked hemoglobin (DCLHb) with that of standard resuscitative fluids in restoring intestinal mucosal oxygenation and villous architecture after hemorrhage. Male rats were bled to a base deficit of 5 +/- 2 nmol/l under propofol anesthesia and monitored for 90 minutes postresuscitation with DCLHb, blood, lactated Ringers solution, albumin, or nothing (DNR) for mucosal oxygen tension (Pmo2) and physiologic and laboratory parameters. Small intestinal histologic specimens were obtained and scored independently by two investigators blinded to therapy on a scale of 0 (normal) to 4 (worst). All treatments restored Pmo2; only DCLHb did so without exceeding baseline values. For untreated rats (DNR), Pmo2 was not restored. Normal mucosal architecture was maintained only in DCLHb-treated rats. As Pmo2 increased, mucosal score improved. In a rat model of controlled hemorrhage, Pmo2 changes measured by an optode correlated with gut histological abnormalities. By these criteria, DCLHb is superior to crystalloid, colloid, and blood in gut resuscitation.