Rex Chung

Influence of resident involvement on trauma care outcomes

HYPOTHESIS Discrepancies exist in complications and outcomes at teaching trauma centers (TTCs) vs nonteaching TCs (NTCs). DESIGN Retrospective review of the National Trauma Data Bank research data sets (January 1, 2007, through December 31, 2008). SETTING Level II TCs. PATIENTS Patients at TTCs were compared with patients at NTCs using demographic, clinical, and outcome data. Regression modeling was used to adjust for confounding factors to determine the effect of house staff presence on failure to rescue, defined as mortality after an in-house complication. MAIN OUTCOME MEASURES The primary outcome measures were major complications, in-hospital mortality, and failure to rescue. RESULTS In total, 162 687 patients were available for analysis, 36 713 of whom (22.6%) were admitted to NTCs. Compared with patients admitted to TTCs, patients admitted to NTCs were older (52.8 vs 50.7 years), had more severe head injuries (8.3% vs 7.8%), and were more likely to undergo immediate operation (15.0% vs 13.2%) or ICU admission (28.1% vs 22.8%) (P < .01 for all). The mean Injury Severity Scores were similar between the groups (10.1 for patients admitted to NTCs vs 10.4 for patients admitted to TTCs, P < .01). Compared with patients admitted to TTCs, patients admitted to NTCs experienced fewer complications (adjusted odds ratio [aOR], 0.63; P < .01), had a lower adjusted mortality rate (aOR, 0.87; P = .01), and were less likely to experience failure to rescue (aOR, 0.81; P = .01). CONCLUSIONS Admission to level II TTCs is associated with an increased risk for major complications and a higher rate of failure to rescue compared with admission to level II NTCs. Further investigation of the differences in care provided by level II TTCs vs NTCs may identify areas for improvement in residency training and processes of care.

Which central venous catheters have the highest rate of catheter-associated deep venous thrombosis: a prospective analysis of 2,128 catheter days in the surgical intensive care unit.

BACKGROUND Catheter-associated deep venous thromboses (CADVTs) are a common occurrence in the surgical intensive care unit (SICU), necessitating central venous catheter (CVC) removal and replacement. Previous studies evaluating risk factors for CADVT in SICU patients are limited, and most lack a true denominator of all CVC days. We sought to determine the true incidence of and risk factors for CADVT based on patient characteristics as well as CVC site, type, and duration of insertion. METHODS The following data from all SICU patients in two urban Level I trauma centers were prospectively collected from 2009 to 2012: demographics, risk factors for DVT, CVC site/type/duration, and duplex results. Sites included the subclavian (SC), internal jugular (IJ), arm (for peripherally inserted central catheter [PICC] lines), and femoral. Types included multilumen (ML), introducer/hemodialysis (I/HD), and PICC. High-risk patients received weekly screening duplex examinations and a CADVT was defined as a DVT being detected on duplex with a CVC in place or within 7 days of removal. Rates of CADVT were normalized per 1,000 CVC days, and independent predictors of CADVT were determined using logistic regression. RESULTS Data were complete for 184 patients, 354 CVCs, and 2,128 CVC days. Fifty-nine CADVTs were diagnosed in 28% of patients. Rates of CADVT were 9 per 1,000 catheter days for SC, 61 for IJ (p < 0.01 vs. SC), 27 for arm (p < 0.01), 36 for femoral (p < 0.01), 22 for ML, 57 for I/HD (p < 0.01 vs. ML), and 27 for PICC (p = 0.24). After adjusting for patient risk factors, predictors of CADVT included the IJ and arm sites (odds ratio, 6.0 and 3.0 compared with SC) and the I/HD type (odds ratio, 2.6 compared with ML, all p < 0.05). CONCLUSION The IJ and arm sites and I/HD type are associated with increased CADVT. These data may be used to determine the optimal site and type of CVC for insertion. LEVEL OF EVIDENCE Prognostic/epidemiologic study, level III.

Long-term effect of trauma splenectomy on blood glucose

BACKGROUND Increasing evidence suggests that the spleen harbors stem cells that act as precursors to insulin-producing pancreas cells. Additionally, small studies with short-term follow-up associate splenectomy with increased rates of diabetes mellitus. The purpose of this study was to analyze the long-term effect of trauma splenectomy on blood glucose. MATERIALS AND METHODS Patients were included if a blood glucose level was measured more than 5 y after trauma splenectomy or laparotomy with bowel repair. Mean blood glucose level was then compared between the two groups. RESULTS During the 10-y study period 61 patients underwent trauma splenectomy and 50 survived until discharge. In comparison, 229 patients underwent trauma laparotomy and bowel repair and 207 survived until discharge. Nine splenectomy patients compared with 12 control patients had, blood glucose measured at least 5 y after initial trauma. Mean follow-up period was not significantly different between groups (splenectomy 82.8 ± 17.6 mo versus control 96.0 ± 44.3 mo, P = 0.41). In the splenectomy cohort mean glucose level was significantly higher compared with the control (114 ± 34 mg/dL versus 90 ± 13 mg/dL, P = 0.04), as was the number of patients with recorded blood glucose level greater than 130 mg/dL (4 patient versus 0 patients P = 0.02). One new diagnosis of diabetes mellitus was noted only in the trauma splenectomy cohort. CONCLUSIONS This small study suggests that trauma splenectomy may be associated with hyperglycemia at long-term follow-up.

The impact of implementing a 24/7 open trauma bed protocol in the surgical intensive care unit on throughput and outcomes.

BACKGROUND Increased emergency department (ED) length of stay (LOS) has been associated with increased mortality in trauma patients. In 2010, we implemented a 24/7 open trauma bed protocol in our designated trauma intensive care units (TICUs) to facilitate rapid admission from the ED. This required maintenance of a daily bump list and timely transferring of patients out of the TICU. We hypothesized that ED LOS and mortality would decrease after implementation. METHODS The following data from patients admitted directly from the ED to any ICU were retrospectively compared before (2009) and after (2011) the implementation of a trauma bed protocol at a Level I trauma center: age, sex, Glasgow Coma Scale (GCS) score, shock on admission (systolic blood pressure < 90 mm Hg), mechanism, injury severity scores (Injury Severity Score [ISS] and Abbreviated Injury Scale [AIS] score), ED LOS, ICU readmission rates, and mortality. RESULTS Of the patients, 267 (17%) of 1,611 before and 262 (21%) of 1,266 (p < 0.01) after the protocol were admitted directly to the ICU, despite similar characteristics. ED LOS decreased from 4.2 ± 4.0 hours to 3.1 ± 2.1 hours (p < 0.01) in all patients as well as patients with an ISS of greater than 24 (3.1 ± 2.5 vs. 2.2 ± 1.6, p < 0.05) and a head AIS score of greater than 2 (4.2 ± 4.9 vs. 3.1 ± 2.0, p = 0.01). Mortality was unchanged for all patients (9% vs. 8%, p = 0.58) but trends toward improved mortality were found after protocol implementation inpatients with an ISS of greater than 24 (30% vs. 13%, p = 0.07) and in patients with a head AIS score of greater than 2 (12% vs. 6%, p = 0.08). A greater proportion of total patients were admitted to a designated TICU after implementation (83% vs. 93%, p < 0.01). ICU readmissions were unchanged (0.3% vs. 1.5%, p = 0.21). CONCLUSION The implementation of a 24/7 open trauma bed protocol in the surgery ICU was associated with a decreased ED LOS and increased admissions to designated TICUs in all patients. Improved throughput was achieved without increases in ICU readmissions. LEVEL OF EVIDENCE Therapeutic study, level IV.

Early propranolol after traumatic brain injury is associated with lower mortality.

BACKGROUND &bgr;-Adrenergic receptor blockers (BBs) administered after trauma blunt the cascade of immune and inflammatory changes associated with injury. BBs are associated with improved outcomes after traumatic brain injury (TBI). Propranolol may be an ideal BB because of its nonselective inhibition and ability to cross the blood-brain barrier. We determined if early administration of propranolol after TBI is associated with lower mortality. METHODS All adults (age ≥ 18 years) with moderate-to-severe TBI (head Abbreviated Injury Scale [AIS] score, 3–5) requiring intensive care unit (ICU) admission at a Level I trauma center from January 1, 2013, to May 31, 2015, were prospectively entered into a database. Administration of early propranolol was dosed within 24 hours of admission at 1 mg intravenous every 6 hours. Patients who received early propranolol after TBI (EPAT) were compared with those who did not (non-EPAT). Data including demographics, hospital length of stay (LOS), ICU LOS, and mortality were collected. RESULTS Over 29 months, 440 patients with moderate-to-severe TBI met inclusion criteria. Early propranolol was administered to 25% (109 of 440) of the patients. The EPAT cohort was younger (49.6 years vs. 60.4 years, p < 0.001), had lower Glasgow Coma Scale (GCS) score (11.7 vs. 12.4, p = 0.003), had lower head AIS score (3.6 vs. 3.9, p = 0.001), had higher admission heart rate (95.8 beats/min vs. 88.4 beats/min, p = 0.002), and required more days on the ventilator (5.9 days vs. 2.6 days, p < 0.001). Similarities were noted in sex, Injury Severity Score (ISS), admission systolic blood pressure, hospital LOS, ICU LOS, and mortality rate. Multivariate regression showed that EPAT was independently associated with lower mortality (adjusted odds ratio, 0.25; p = 0.012). CONCLUSION After adjusting for predictors of mortality, early administration of propranolol after TBI was associated with improved survival. Future studies are needed to identify additional benefits and optimal dosing regimens. LEVEL OF EVIDENCE Therapeutic study, level IV.

Body mass index strongly impacts the diagnosis and incidence of heparin-induced thrombocytopenia in the surgical intensive care unit.

BACKGROUND The obese state has been linked to several immune-mediated conditions. Our objective was to examine the association of body mass index (BMI) with the diagnosis of heparin-induced thrombocytopenia (HIT). METHODS Prospectively collected data on patients in the surgical and cardiac intensive care unit suspected of having HIT between January 2007 and August 2014 were analyzed. Patients were categorized into five discrete BMI (kg/m2) groups and compared. Data collected included Warkentin 4-T scores, antiplatelet factor 4 (anti-PF4OD) values, serotonin release assay values, and thromboembolic diseases. HIT positivity was defined as serotonin release assay value greater than 20%. RESULTS Of 304 patients meeting inclusion criteria, mean (SD) age was 62.1 (16.5) years, 59% were male, and mean (SD) BMI was 27 (6) kg/m2. Thirty-six (12%) were positive for HIT. Incidence of HIT increased progressively with BMI (0%, 8%, 11%, 19%, 36%; p < 0.001). Compared with patients with normal BMI, patients with a BMI of 30 kg/m2 to 39.9 kg/m2 had a 200% increase in the odds for HIT (odds ratio [OR], 2.94; 95% confidence interval [CI], 1.20–7.54; p = 0.019), while patients with a BMI of 40 kg/m2 or greater had a 600% increase (OR, 6.98; 95% CI, 1.59–28.2; p = 0.012). After regression analysis, BMI remained an independent predictor of the development of HIT (adjusted OR per kg/m2, 1.08; 95% CI, 1.02–1.14; p = 0.010). Anti-PF4OD values greater than or equal to 2.0 also increased with BMI (p < 0.001). In-hospital mortality increased significantly with BMI above normal (p = 0.026). Warkentin 4-T scores, deep venous thrombosis, pulmonary embolism, and stroke incidence did not correlate with changes in BMI. CONCLUSION Increasing BMI seems to be strongly associated with increased rates of HIT in intensive care unit patients. Obesity is an important new clinical variable for estimating the pretest probability of HIT, and patient “thickness” could be considered a fifth “T” of the 4-T scoring system. Additional biochemical work is indicated to decipher the role of obesity in this immune-mediated condition. LEVEL OF EVIDENCE Prognostic/epidemiologic study, level III.

Impact of body mass index on injury in abdominal stab wounds: implications for management.

BACKGROUND Although it is assumed that obese patients are naturally protected against anterior abdominal stab wounds, the relationship has never been formally studied. We sought to examine the impact of body mass index (BMI) on severity of sustained injury, need for operation, and patient outcomes. MATERIALS AND METHODS We conducted a review of all patients presenting with abdominal stab wounds at an urban level I trauma center from January 2000-December 2012. Patients were divided into groups based on their BMI (<18.5, 18.5-29.9, 30-35, and >35). Data abstracted included baseline demographics, physiologic data, and characterization of whether the stab wound had violated the peritoneum, caused intra-abdominal injury, or required an operation that was therapeutic. The one-sided Cochran-Armitage trend test was used for significance testing of the protective effect. RESULTS Of 281 patients with abdominal stab wounds, 249 had complete data for evaluation. Chest and abdomen abbreviated injury scale trends decreased with increasing BMI, as did overall injury severity score, the percent of patients severely injured (injury severity score ≥ 25), and length of intensive care unit stay. Rates of peritoneal violation (100%, 84%, 77%, and 74%; P = 0.077), visceral injury (83%, 56%, 50%, and 30%; P = 0.022), and injury requiring a therapeutic operation (67%, 45%, 40%, and 20%; P = 0.034) all decreased with increasing BMI. Patients in the thinnest group required an operation three times more often than those in the most obese. CONCLUSIONS Increased BMI protects patients with abdominal stab wounds and is associated with lower incidence of severe injury and need for operation. Heavier patients may be more suitable to observation and serial examinations, whereas very thin patients are more likely to require an operation and be critically injured.

Clostridium difficile increases the risk for venous thromboembolism

BACKGROUND Inflammatory bowel disease is associated with a higher risk for venous thromboembolism (VTE). Whether Clostridium difficile infection similarly increases this risk is unknown. METHODS This was a retrospective analysis of patients admitted to the surgical intensive care unit (ICU) at the Cedars-Sinai Medical Center from February 2011 to July 2013. The 2 groups were compared using standard statistical methodology. RESULTS During the 30-month study period, a total of 1,728 patients were admitted to the surgical ICU. A total of 64 patients (3.7%) tested positive for C. difficile. The use of chemical prophylaxis for VTE was significantly higher in the C. difficile group (64.1% vs 46.2%, P = .005). Nonetheless, C. difficile patients had a higher risk for development of a VTE (23.4% vs 11.0%, adjusted odds ratio [95% confidence interval]: 1.87 [1.01 to 3.48], P = .048). In a forward logistic regression model, C. difficile was found to be independently associated with the development of VTE (adjusted odds ratio [95% confidence interval]: 1.87 [1.00 to 3.47], P = .049). CONCLUSIONS C. difficile infection increases the risk for VTE in surgical patients admitted to the ICU.

Elevated systolic blood pressure after trauma: Tolerated in the elderly

BACKGROUND We undertook the current study to determine the impact of elevated admission systolic blood pressure (SBP) on trauma patients without severe brain injury. MATERIALS AND METHODS We conducted a retrospective review of the Los Angeles County Trauma System database to identify all patients with moderate to severe injuries (injury severity score >9) admitted between 2003 and 2008. Patients with head abbreviated injury score >3 were excluded. We divided the remaining patients into three age cohorts and conducted multivariate regression modeling at increasing SBP thresholds to identify independent predictors of mortality. RESULTS A total of 23,931 patients met inclusion criteria. Overall mortality was 8.6% and it increased with age across the three groups. The admission SBP thresholds associated with significantly increased mortality in the young and middle-aged were >190 mm Hg (AOR 1.5, P = 0.04) and >180 mm Hg (AOR 1.5, P = 0.01), respectively. In the elderly, no admission SBP threshold was associated with significantly increased mortality. Interestingly, several elevated admission SBP thresholds were associated with significantly reduced mortality in the elderly (>150 mm Hg AOR 0.6, P < 0.01; >160 mm Hg AOR 0.6, P < 0.01; and >170 mm Hg AOR 0.7, P = 0.02). CONCLUSIONS The admission SBP thresholds that predicted higher mortality for the young and middle-aged were >190 mm Hg and >180 mm Hg, respectively. Elderly trauma patients tolerated higher admission SBP than their younger counterparts and multiple elevated SBP thresholds were associated with significantly reduced mortality in the elderly.