David T. Efron

Race and Insurance Status as Risk Factors for Trauma Mortality

OBJECTIVE To determine the effect of race and insurance status on trauma mortality. METHODS Review of patients (aged 18-64 years; Injury Severity Score > or = 9) included in the National Trauma Data Bank (2001-2005). African American and Hispanic patients were each compared with white patients and insured patients were compared with uninsured patients. Multiple logistic regression analyses determined differences in survival rates after adjusting for demographics, injury severity (Injury Severity Score and revised Trauma Score), severity of head and/or extremity injury, and injury mechanism. RESULTS A total of 429 751 patients met inclusion criteria. African American (n = 72,249) and Hispanic (n = 41,770) patients were less likely to be insured and more likely to sustain penetrating trauma than white patients (n = 262,878). African American and Hispanic patients had higher unadjusted mortality rates (white, 5.7%; African American, 8.2%; Hispanic, 9.1%; P = .05 for African American and Hispanic patients) and an increased adjusted odds ratio (OR) of death compared with white patients (African American OR, 1.17; 95% confidence interval [CI], 1.10-1.23; Hispanic OR, 1.47; 95% CI, 1.39-1.57). Insured patients (47%) had lower crude mortality rates than uninsured patients (4.4% vs 8.6%; P = .05). Insured African American and Hispanic patients had increased mortality rates compared with insured white patients. This effect worsened for uninsured patients across groups (insured African American OR, 1.2; 95% CI, 1.08-1.33; insured Hispanic OR, 1.51; 95% CI, 1.36-1.64; uninsured white OR, 1.55; 95% CI, 1.46-1.64; uninsured African American OR, 1.78; 95% CI, 1.65-1.90; uninsured Hispanic OR, 2.30; 95% CI, 2.13-2.49). The reference group was insured white patients. CONCLUSION Race and insurance status each independently predicts outcome disparities after trauma. African American, Hispanic, and uninsured patients have worse outcomes, but insurance status appears to have the stronger association with mortality after trauma.

Association Between Helicopter vs Ground Emergency Medical Services and Survival for Adults With Major Trauma

CONTEXT Helicopter emergency medical services and their possible effect on outcomes for traumatically injured patients remain a subject of debate. Because helicopter services are a limited and expensive resource, a methodologically rigorous investigation of its effectiveness compared with ground emergency medical services is warranted. OBJECTIVE To assess the association between the use of helicopter vs ground services and survival among adults with serious traumatic injuries. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study involving 223,475 patients older than 15 years, having an injury severity score higher than 15, and sustaining blunt or penetrating trauma that required transport to US level I or II trauma centers and whose data were recorded in the 2007-2009 versions of the American College of Surgeons National Trauma Data Bank. INTERVENTIONS Transport by helicopter or ground emergency services to level I or level II trauma centers. MAIN OUTCOME MEASURES Survival to hospital discharge and discharge disposition. RESULTS A total of 61,909 patients were transported by helicopter and 161,566 patients were transported by ground. Overall, 7813 patients (12.6%) transported by helicopter died compared with 17,775 patients (11%) transported by ground services. Before propensity score matching, patients transported by helicopter to level I and level II trauma centers had higher Injury Severity Scores. In the propensity score-matched multivariable regression model, for patients transported to level I trauma centers, helicopter transport was associated with an improved odds of survival compared with ground transport (odds ratio [OR], 1.16; 95% CI, 1.14-1.17; P < .001; absolute risk reduction [ARR], 1.5%). For patients transported to level II trauma centers, helicopter transport was associated with an improved odds of survival (OR, 1.15; 95% CI, 1.13-1.17; P < .001; ARR, 1.4%). A greater proportion (18.2%) of those transported to level I trauma centers by helicopter were discharged to rehabilitation compared with 12.7% transported by ground services (P < .001), and 9.3% transported by helicopter were discharged to intermediate facilities compared with 6.5% by ground services (P < .001). Fewer patients transported by helicopter left level II trauma centers against medical advice (0.5% vs 1.0%, P < .001). CONCLUSION Among patients with major trauma admitted to level I or level II trauma centers, transport by helicopter compared with ground services was associated with improved survival to hospital discharge after controlling for multiple known confounders.

Prehospital intravenous fluid administration is associated with higher mortality in trauma patients: A national trauma data bank analysis

OBJECTIVE Prehospital intravenous (IV) fluid administration is common in trauma patients, although little evidence supports this practice. We hypothesized that trauma patients who received prehospital IV fluids have higher mortality than trauma patients who did not receive IV fluids in the prehospital setting. METHODS We performed a retrospective cohort study of patients from the National Trauma Data Bank. Multiple logistic regression was used with mortality as the primary outcome measure. We compared patients with versus without prehospital IV fluid administration, using patient demographics, mechanism, physiologic and anatomic injury severity, and other prehospital procedures as covariates. Subset analysis was performed based on mechanism (blunt/penetrating), hypotension, immediate surgery, severe head injury, and injury severity score. RESULTS A total of 776,734 patients were studied. Approximately half (49.3%) received prehospital IV. Overall mortality was 4.6%. Unadjusted mortality was significantly higher in patients receiving prehospital IV fluids (4.8% vs. 4.5%, P < 0.001). Multivariable analysis demonstrated that patients receiving IV fluids were significantly more likely to die (odds ratio [OR] 1.11, 95% confidence interval [CI] 1.05–1.17). The association was identified in nearly all subsets of trauma patients. It is especially marked in patients with penetrating mechanism (OR 1.25, 95% CI 1.08–1.45), hypotension (OR 1.44, 95% CI1.29–1.59), severe head injury (OR 1.34, 95% CI 1.17–1.54), and patients undergoing immediate surgery (OR 1.35, 95% CI 1.22–1.50). CONCLUSIONS The harm associated with prehospital IV fluid administration is significant for victims of trauma. The routine use of prehospital IV fluid administration for all trauma patients should be discouraged.

Influence of the National Trauma Data Bank on the Study of Trauma Outcomes: Is it Time to Set Research Best Practices to Further Enhance Its Impact?

BACKGROUND Risk-adjusted analyses are critical in evaluating trauma outcomes. The National Trauma Data Bank (NTDB) is a statistically robust registry that allows such analyses; however, analytical techniques are not yet standardized. In this study, we examined peer-reviewed manuscripts published using NTDB data, with particular attention to characteristics strongly associated with trauma outcomes. Our objective was to determine if there are substantial variations in the methodology and quality of risk-adjusted analyses and therefore, whether development of best practices for risk-adjusted analyses is warranted. STUDY DESIGN A database of all studies using NTDB data published through December 2010 was created by searching PubMed and Embase. Studies with multivariate risk-adjusted analyses were examined for their central question, main outcomes measures, analytical techniques, covariates in adjusted analyses, and handling of missing data. RESULTS Of 286 NTDB publications, 122 performed a multivariable adjusted analysis. These studies focused on clinical outcomes (51 studies), public health policy or injury prevention (30), quality (16), disparities (15), trauma center designation (6), or scoring systems (4). Mortality was the main outcome in 98 of these studies. There were considerable differences in the covariates used for case adjustment. The 3 covariates most frequently controlled for were age (95%), Injury Severity Score (85%), and sex (78%). Up to 43% of studies did not control for the 5 basic covariates necessary to conduct a risk-adjusted analysis of trauma mortality. Less than 10% of studies used clustering to adjust for facility differences or imputation to handle missing data. CONCLUSIONS There is significant variability in how risk-adjusted analyses using data from the NTDB are performed. Best practices are needed to further improve the quality of research from the NTDB.

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.

Central pancreatectomy with pancreaticogastrostomy for benign pancreatic pathology.

Benign lesions of the neck and proximal body of the pancreas pose an interesting surgical challenge. If the lesions are not amenable to simple enucleation, surgeons may be faced with the choice of performing a right-sided resection (pancreaticoduodenectomy) or a left-sided resection (distal pancreatectomy) to include the lesion, resulting in resection of a substantial amount of normal pancreatic parenchyma. Central pancreatic resection has been reported with Roux-en-Y pancreaticojejunostomy reconstruction; however, this interrupts small bowel continuity and obligates an additional anastomosis.We have reviewed our experience with central pancreatectomy with pancreaticogastrostomy (PG) for benign central pancreatic pathology. Between January 1999 and December 2002, 14 central pancreatectomies were performed with PG reconstruction. There were 7 women and 7 men with a mean age of 60.9 years. Five resections were performed for islet cell tumors, three were performed for noninvasive intraductal papillary mucinous neoplasms, two were performed for serous cystadenoma, and one each was performed for a simple cyst, pseudocyst, mucinous metaplasia, and focal chronic pancreatitis. Seven out of 14 patients experienced a total of 10 complications. Pancreatic fistulae manifested by drainage of amylase-rich fluid from the operatively placed drains developed in 5 patients (36%). Reoperation or interventional radiologic procedures were not required in any patient with a fistula. Postoperative follow-up demonstrated 13 out of 14 patients to be alive and well without evidence of pancreatic insufficiency. One patient died at home on postoperative day 57 of cardiac pathology. Central pancreatectomy withPGis a safe and effective procedure that allows for preservation of pancreatic endocrine and exocrine function without disruption of enteric continuity. The complication of pancreatic fistula was managed conservatively via maintenance of operatively placed drains.

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.

Hazards of benchmarking complications with the National Trauma Data Bank: numerators in search of denominators.

BACKGROUND Complication rates after trauma may serve as important indicators of quality of care. Meaningful performance benchmarks for complication rates require reference standards from valid and reliable data. Selection of appropriate numerators and denominators is a major consideration for data validity in performance improvement and benchmarking. We examined the suitability of the National Trauma Data Bank (NTDB) as a reference for benchmarking trauma center complication rates. METHOD We selected the five most commonly reported complications in the NTDB v. 6.1 (pneumonia, urinary tract infection, acute respiratory distress syndrome, deep vein thrombosis, myocardial infarction). We compared rates for each complication using three different denominators defined by different populations at risk. A-all patients from all 700 reporting facilities as the denominator (n = 1,466,887); B-only patients from the 441 hospitals reporting at least one complication (n = 1,307,729); C-patients from hospitals reporting at least one occurrence of each specific complication, giving a unique denominator for each complication (n range = 869,675-1,167,384). We also looked at differences in hospital characteristics between complication reporters and nonreporters. RESULTS There was a 12.2% increase in the rate of each complication when patients from facilities not reporting any complications were excluded from the denominator. When rates were calculated using a unique denominator for each complication, rates increased 25% to 70%. The change from rate A to rate C produced a new rank order for the top five complications. When compared directly, rates B and C were also significantly different for all complications (all p < 0.01). Hospitals that reported complication information had significantly higher annual admissions and were more likely to be designated level I or II trauma centers and be university teaching hospitals. CONCLUSION There is great variability in complication data reported in the NTDB that may introduce bias and significantly influence rates of complications reported. This potential for bias creates a challenge for appropriately interpreting complication rates for hospital performance benchmarking. We recognize the value of large aggregated registries such as the NTDB as a valuable tool for benchmarking and performance improvement purposes. However, we strongly advocate the need for conscientious selection of numerators and denominators that serve as the basic foundation for research.

Supplemental L-arginine enhances wound healing in diabetic rats

L‐arginine has been shown to enhance wound strength and collagen deposition in rodents and humans. Diabetes mellitus, which impairs wound healing, is accompanied by a reduction in nitric oxide at the wound site. The amino acid L‐arginine is the only substrate for nitric oxide synthesis. We sought to determine whether supplemental L‐arginine can restore the impaired wound healing of diabetic rats. Fifty‐six male Lewis rats were used in this study, of which twenty‐nine rats were rendered diabetic 7 days prior to surgery with intraperitoneal streptozotocin. Twenty‐seven untreated rats served as controls. Animals underwent a dorsal skin incision with implantation of polyvinyl‐alcohol sponges. Sixteen diabetic and 14 normal rats received 1 g/kg/day of L‐arginine by injection, while the remainder received saline injections only. Animals were euthanized 10 days postwounding, and their wounds were analyzed for breaking strength. The wound sponges were assayed for total hydroxyproline and nitrite/nitrate content. Plasma and wound fluid concentrations of L‐arginine, ornithine, and citrulline were determined. Wound sponge RNA was extracted and subjected to Northern blot analysis for procollagen I and III. Diabetic wounds had greatly decreased breaking strengths compared with controls. L‐arginine significantly enhanced wound breaking strengths in both control (+23%) and diabetic animals (+44%), and also increased wound hydroxyproline levels in both diabetic (+40%) and control animals (+24%) as compared to their saline‐treated counterparts. mRNA for procollagen I and III were elevated by L‐arginine treatment in both diabetic rats and controls. Treatment with L‐arginine significantly increased wound fluid nitrite/nitrate levels in diabetic animals. The data show that the impaired healing of diabetic wounds can be partially corrected by L‐arginine supplementation, and that this effect is accompanied by enhanced wound nitric oxide synthesis. (WOUND REP REG 2003;11:198–203)

Improved Prophylaxis and Decreased Rates of Preventable Harm With the Use of a Mandatory Computerized Clinical Decision Support Tool for Prophylaxis for Venous Thromboembolism in Trauma

OBJECTIVE Venous thromboembolism is associated with substantial morbidity and mortality and is largely preventable. Despite this fact, appropriate prophylaxis is vastly underutilized. To improve compliance with best practice prophylaxis for VTE in hospitalized trauma patients, we implemented a mandatory computerized provider order entry-based clinical decision support tool. The system required completion of checklists of VTE risk factors and contraindications to pharmacologic prophylaxis. With this tool, we were able to determine a patients risk stratification level and recommend appropriate prophylaxis. To evaluate the effect of our mandatory computerized provider order entry-based clinical decision support tool on compliance with prophylaxis guidelines for venous thromboembolism (VTE) and VTE outcomes among admitted adult trauma patients. DESIGN Retrospective cohort study (from January 2007 through December 2010). SETTING University-based, state-designated level 1 adult trauma center. PATIENTS A total of 1599 hospitalized adult trauma patients with a hospital length of stay greater than 1 day. MAIN OUTCOME MEASURES The primary outcome measure was the proportion of patients who were ordered risk-appropriate guideline-suggested VTE prophylaxis. The secondary outcome measure was the proportion of patients with any preventable VTE (defined as VTE in a patient not ordered guideline-appropriate VTE prophylaxis), pulmonary embolism, and/or deep vein thrombosis. RESULTS Compliance with guideline-appropriate prophylaxis increased from 66.2% to 84.4% (P < .001). The rate of preventable harm from VTE decreased from 1.0% to 0.17% (P = .04). CONCLUSIONS Implementation of a mandatory computerized provider order entry-based clinical decision support tool significantly improved compliance with VTE prophylaxis guidelines in hospitalized adult trauma patients. This improved compliance was associated with a significant decrease in the rate of preventable harm, which was defined as VTE events in patients not ordered appropriate prophylaxis.