The role of number of affected vessels on radiologic and clinical outcomes of patients with blunt cerebrovascular injury.

OBJECTIVE: There is a lack of data on the role of characteristics of injured vessels on the outcomes of patients with blunt cerebrovascular injuries (BCVIs). The aim of this study was to assess the effect of the number (single vs multiple) of injured vessels on outcomes. METHODS: This is a retrospective study at two American College of Surgeons Level I trauma centers (2017-2021). Adult (>16 years) trauma patients with BCVIs are included. Injuries were graded by the Denver Scale based on the initial computed tomography angiography (CTA). Early repeat CTA was performed 7 to 10 days after diagnosis. Patients were stratified by the number (single vs multiple) of the involved vessels. Outcomes included progression of BCVIs on repeat CTA, stroke, and in-hospital mortality attributable to BCVIs. Multivariable regression analyses were performed to identify the association between the number of injured vessels and outcomes. RESULTS: A total of 491 patients with 591 injured vessels (285 carotid and 306 vertebral arteries) were identified. Sixty percent were male, the mean age was 44 years, and the median Injury Severity Score was 18 (interquartile range, 11-25). Overall, 18% had multiple-vessel injuries, 16% had bilateral vessel injuries, and 3% had multiple injuries on the same side. The overall rates of progression to higher-grade injuries, stroke, and mortality were 23%, 7.7%, and 8.8%, respectively. On uni- and multivariable analyses, multiple BCVIs were associated with progression to higher-grade injuries on repeat imaging, stroke, and mortality compared with single-vessel injuries. CONCLUSIONS: BCVIs with multiple injured vessels are more likely to progress to higher grades on repeat CTA, with multiple injuries independently associated with worse clinical outcomes, compared with those with single injuries. These findings highlight the importance of incorporating the number of injured vessels in clinical decision-making and in defining protocols for repeat imaging.

Abdominal computed tomography scoring systems and experienced radiologists in the radiological diagnosis of small bowel and mesenteric injury.

PURPOSE: Blunt bowel and/or mesenteric injury requiring surgery presents a diagnostic challenge. Although computed tomography (CT) imaging is standard following blunt trauma, findings can be nonspecific. Most studies have focused on the diagnostic value of CT findings in identifying significant bowel and/or mesenteric injury (sBMI). Some studies have described scoring systems to assist with diagnosis. Little attention, has been given to radiologist interpretation of CT scans. This study compared the discriminative ability of scoring systems (BIPS and RAPTOR) with radiologist interpretation in identifying sBMI. METHODS: We conducted a retrospective chart review of trauma patients with suspected sBMI. CT images were reviewed in a blinded fashion to calculate BIPS and RAPTOR scores. Sensitivity and specificity were compared between BIPS, RAPTOR, and the admission CT report with respect to identifying sBMI. RESULTS: One hundred sixty-two patients were identified, 72 (44%) underwent laparotomy and 43 (26.5%) had sBMI. Sensitivity and specificity were: BIPS 49% and 87%, AUC 0.75 (0.67-0.81), P < 0.001; RAPTOR 46% and 82%, AUC 0.72 (0.64-0.79), P < 0.001; radiologist impression 81% and 71%, AUC 0.82(0.75-0.87), P < 0.001. The discriminative ability of the radiologist impression was higher than RAPTOR (P = 0.04) but not BIPS (P = 0.13). There was not a difference between RAPTOR vs. BIPS (P = 0.55). CONCLUSION: Radiologist interpretation of the admission CT scan was discriminative of sBMI. Although surgical vigilance, including evaluation of the CT images and patient, remains fundamental to early diagnosis, the radiologist's impression of the CT scan can be used in clinical practice to simplify the approach to patients with abdominal trauma.

Practice Variation in Vena Cava Filter Use Among Trauma Centers in the National Trauma Database.

BACKGROUND: Agreement regarding indications for vena cava filter (VCF) utilization in trauma patients has been in flux since the filter's introduction. As VCF technology and practice guidelines have evolved, the use of VCF in trauma patients has changed. This study examines variation in VCF placement among trauma centers. MATERIALS AND METHODS: A retrospective study was performed using data from the National Trauma Data Bank (2005-2014). Trauma centers were grouped according to whether they placed VCFs during the study period (VCF+/VCF-). A multivariable probit regression model was fit to predict the number of VCFs used among the VCF+ centers (the expected [E] number of VCF per center). The ratio of observed VCF placement (O) to expected VCFs (O:E) was computed and rank ordered to compare interfacility practice variation. RESULTS: In total, 65,482 VCFs were placed by 448 centers. Twenty centers (4.3%) placed no VCFs. The greatest predictors of VCF placement were deep vein thrombosis, spinal cord paralysis, and major procedure. The strongest negative predictor of VCF placement was admission during the year 2014. Among the VCF+ centers, O:E varied by nearly 500%. One hundred fifty centers had an O:E greater than one. One hundred sixty-nine centers had an O:E less than one. CONCLUSIONS: Substantial variation in practice is present in VCF placement. This variation cannot be explained only by the characteristics of the patients treated at these centers but could be also due to conflicting guidelines, changing evidence, decreasing reimbursement rates, or the culture of trauma centers.

Cefazolin Monotherapy Versus Cefazolin Plus Aminoglycosides for Antimicrobial Prophylaxis of Type III Open Fractures.

BACKGROUND: There are conflicting recommendations between organizations regarding aminoglycoside use for the prophylaxis of type III open fractures. STUDY QUESTION: To compare cefazolin monotherapy versus cefazolin plus aminoglycoside therapy for prophylaxis of type III open fractures in trauma patients. STUDY DESIGN: This was a multicenter, retrospective, cohort study conducted in 3 academic medical centers in the United States. Consecutive adult trauma patients with type III open fractures between January 2014 and September 2016 were included. Patients were divided into 2 groups: (1) cefazolin monotherapy versus (2) cefazolin plus aminoglycoside. MEASURES AND OUTCOMES: The primary outcome measure was the occurrence of infection at the open fracture site. The secondary outcome measure was the occurrence of acute kidney injury. RESULTS: There were 134 patients included in the study cohort. Of these, 39 received cefazolin monotherapy and 95 received cefazolin plus aminoglycoside. Overall, the mean age was 39 ± 15 years, 105 (78%) were male, and the most common fracture location was tibia/fibula (n = 74, 56%). Infection at the open fracture site occurred in 6 of 39 patients (15%) in the cefazolin monotherapy group and 15 of 95 patients (16%) in the cefazolin plus aminoglycoside group (P = 1.000). Acute kidney injury occurred in 0 of 39 (0%) in the cefazolin monotherapy group and 1 of 95 (1%) in the cefazolin plus aminoglycoside group (P = 1.000). CONCLUSIONS: Cefazolin monotherapy may be appropriate for antimicrobial prophylaxis of type III open fractures in trauma patients.

Transfusion of plasma, platelets, and red blood cells in a 1:1:1 vs a 1:1:2 ratio and mortality in patients with severe trauma: the PROPPR randomized clinical trial.

IMPORTANCE: Severely injured patients experiencing hemorrhagic shock often require massive transfusion. Earlier transfusion with higher blood product ratios (plasma, platelets, and red blood cells), defined as damage control resuscitation, has been associated with improved outcomes; however, there have been no large multicenter clinical trials. OBJECTIVE: To determine the effectiveness and safety of transfusing patients with severe trauma and major bleeding using plasma, platelets, and red blood cells in a 1:1:1 ratio compared with a 1:1:2 ratio. DESIGN, SETTING, AND PARTICIPANTS: Pragmatic, phase 3, multisite, randomized clinical trial of 680 severely injured patients who arrived at 1 of 12 level I trauma centers in North America directly from the scene and were predicted to require massive transfusion between August 2012 and December 2013. INTERVENTIONS: Blood product ratios of 1:1:1 (338 patients) vs 1:1:2 (342 patients) during active resuscitation in addition to all local standard-of-care interventions (uncontrolled). MAIN OUTCOMES AND MEASURES: Primary outcomes were 24-hour and 30-day all-cause mortality. Prespecified ancillary outcomes included time to hemostasis, blood product volumes transfused, complications, incidence of surgical procedures, and functional status. RESULTS: No significant differences were detected in mortality at 24 hours (12.7% in 1:1:1 group vs 17.0% in 1:1:2 group; difference, -4.2% [95% CI, -9.6% to 1.1%]; P = .12) or at 30 days (22.4% vs 26.1%, respectively; difference, -3.7% [95% CI, -10.2% to 2.7%]; P = .26). Exsanguination, which was the predominant cause of death within the first 24 hours, was significantly decreased in the 1:1:1 group (9.2% vs 14.6% in 1:1:2 group; difference, -5.4% [95% CI, -10.4% to -0.5%]; P = .03). More patients in the 1:1:1 group achieved hemostasis than in the 1:1:2 group (86% vs 78%, respectively; P = .006). Despite the 1:1:1 group receiving more plasma (median of 7 U vs 5 U, P < .001) and platelets (12 U vs 6 U, P < .001) and similar amounts of red blood cells (9 U) over the first 24 hours, no differences between the 2 groups were found for the 23 prespecified complications, including acute respiratory distress syndrome, multiple organ failure, venous thromboembolism, sepsis, and transfusion-related complications. CONCLUSIONS AND RELEVANCE: Among patients with severe trauma and major bleeding, early administration of plasma, platelets, and red blood cells in a 1:1:1 ratio compared with a 1:1:2 ratio did not result in significant differences in mortality at 24 hours or at 30 days. However, more patients in the 1:1:1 group achieved hemostasis and fewer experienced death due to exsanguination by 24 hours. Even though there was an increased use of plasma and platelets transfused in the 1:1:1 group, no other safety differences were identified between the 2 groups. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01545232.

Erythrocyte storage increases rates of NO and nitrite scavenging: implications for transfusion-related toxicity.

Storage of erythrocytes in blood banks is associated with biochemical and morphological changes to RBCs (red blood cells). It has been suggested that these changes have potential negative clinical effects characterized by inflammation and microcirculatory dysfunction which add to other transfusion-related toxicities. However, the mechanisms linking RBC storage and toxicity remain unclear. In the present study we tested the hypothesis that storage of leucodepleted RBCs results in cells that inhibit NO (nitric oxide) signalling more so than younger cells. Using competition kinetic analyses and protocols that minimized contributions from haemolysis or microparticles, our data indicate that the consumption rates of NO increased ~40-fold and NO-dependent vasodilation was inhibited 2-4-fold comparing 42-day-old with 0-day-old RBCs. These results are probably due to the formation of smaller RBCs with increased surface area: volume as a consequence of membrane loss during storage. The potential for older RBCs to affect NO formation via deoxygenated RBC-mediated nitrite reduction was also tested. RBC storage did not affect deoxygenated RBC-dependent stimulation of nitrite-induced vasodilation. However, stored RBCs did increase the rates of nitrite oxidation to nitrate in vitro. Significant loss of whole-blood nitrite was also observed in stable trauma patients after transfusion with 1 RBC unit, with the decrease in nitrite occurring after transfusion with RBCs stored for >25 days, but not with younger RBCs. Collectively, these data suggest that increased rates of reactions between intact RBCs and NO and nitrite may contribute to mechanisms that lead to storage-lesion-related transfusion risk.

From bedside to bedside: how iterative clinical research influenced the diagnosis and management of pneumonia at the Elvis Presley Trauma Center.

Ventilator-associated pneumonia is a well-acknowledged complication after hospitalization for injury or surgical emergency. The contribution to the literature on this topic by Dr Timothy Fabian and the Memphis group at the Elvis Presley Trauma Center resulted in the contemporary recognition that the diagnosis and management of pneumonia is an essential component of surgical critical care. During three decades, the Memphis group, under Dr Fabian's leadership, performed numerous clinical studies that led to the publication of over 40 articles concerning the epidemiology, diagnosis, and treatment of pneumonia after injury. The purpose of this review is to survey the consecutive studies from Memphis specifically that led to the development of a clinical pathway that has stood the test of time. Examination of the research output during this period provides a case study in how bedside clinical research can inform clinical practice and is a model for applied science in the intensive care unit.

Surgeon compassion may mitigate quality of life disparities associated with health literacy.

Objectives: Patients with health literacy (HL) disparities are less likely to comprehend hospital discharge instructions and less satisfied with physician communication. In this prospective cohort study, we sought to examine the interaction of HL, physician communication, and quality of life after hospital discharge among postoperative emergency surgery and trauma patients. Methods: Emergency surgery and trauma surgery patients were prospectively enrolled between December 2020 and December 2021 at an urban level 1 trauma center. Newest Vital Sign (NVS) instrument was used to measure HL during hospitalization. After discharge, patients were administered Revised Trauma Quality of Life (RT-QOL) and Interpersonal Processes of Care (IPC) instruments. An adjusted regression model was used to determine associations among NVS the emotional well-being subscale on the RT-QOL, and patient perception of physician compassion and respect on the IPC. Results: 94 patients completed all instruments. HL was proficient (high HL) in 59.6% and less than proficient (low HL) in 40.4%. HL was positively associated with RT-QOL emotional well-being, r(94)=0.212, p=0.040. However, higher rating of surgeon compassion and respect on IPC moderated the relationship between HL and emotional well-being such that patients with low HL and high perception of physician compassion and respect had similar emotional well-being as the high HL group (p=0.042). Conclusion: Favorable patient perception of surgeon compassion and respect was correlated with higher emotional well-being, independent of HL proficiency. Although the allocation of resources toward improving HL disparities remains warranted, improving patient perception of caregiver compassion during hospitalization may be a target of opportunity with respect to improving quality of life after hospital discharge. Level of evidence: Level III.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) prior to interfacility transfer: Who might benefit in a statewide trauma system?

BACKGROUND: Rural trauma patients are often seen at lower-level trauma centers before transfer and have higher mortality than those seen initially at a Level 1 Trauma Center. This study aims to describe the potential for Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) to bridge this mortality gap. METHODS: We queried the Arizona Trauma Registry between 2014 and 2017 for hypotensive patients who were later transported to a level 1 center. REBOA candidates were identified as those with injuries consistent with major infra-diaphragmatic torso hemorrhage as the likely cause of death. RESULTS: Of 17,868 interfacility transfers during the study period, 333 met inclusion criteria and had sufficient data for evaluation. 26 of the 333 patients were identified as REBOA candidates. CONCLUSIONS: Our study suggests that REBOA may be an effective means to extend survivability to those severely injured trauma patients needing interfacility transfer to a higher level of care.

Pentobarbital coma for management of intracranial hypertension following traumatic brain injury: Lack of early response to treatment portends poor outcomes.

INTRODUCTION: Traumatic brain injury (TBI) results in the death of over 50,000 and the permanent disability of 80,000 individuals annually in the United States. Much of the permanent disability is the result of secondary brain injury from intracranial hypertension (ICH). Pentobarbital coma is often instituted following the failure of osmotic interventions and sedation to control intracranial pressure (ICP). The goal of this study was to evaluate the efficacy of pentobarbital coma with respect to ICP management and long-term functional outcome. METHODS: Traumatic brain injury patients who underwent pentobarbital coma at a level 1 trauma center between 2014 and 2021 were identified. Patient demographics, injury characteristics, Glasgow Coma Scale (GCS) scores, intracranial pressures (ICPs), and outcomes were obtained from the trauma registry as well as inpatient and outpatient medical records. The proportion of ICPs below 20 for each hospitalized patient-day was calculated. The primary outcome measured was GCS score at the last follow-up visit. RESULTS: 25 patients were identified, and the majority were male (n â€‹= â€‹23, 92%) with an average age of 30.0 years â€‹± â€‹12.9 and median injury severity score of 30 (21.5-33.5). ICPs were monitored for all patients with a median of 464 (326-1034) measurements. The average hospital stay was 16.9 days â€‹± â€‹11.5 and intensive care stay was 16.9 â€‹± â€‹10.8 days. 9 (36.0%) patients survived to hospital discharge. Mean follow-up time in months was 36.9 â€‹± â€‹28.0 (min-max 3-80). 7 of the 9 surviving patients presented as GCS 15 on follow-up and the remaining were both GCS 9. Patients presenting at last follow-up with GCS 15 had a significantly higher proportion of controlled ICPs throughout their hospitalization compared to patients who expired or with follow-up GCS <15 (GCS 15: 88% â€‹± â€‹10% vs. GCS <15 or dead: 68% â€‹± â€‹22%, P â€‹= â€‹0.006). A comparison of the daily proportion of controlled ICPs by group revealed negligible differences prior to pentobarbital initiation. Groups diverged nearly immediately upon pentobarbital coma initiation with a higher proportion of controlled ICPs for patients with follow-up GCS of 15. CONCLUSION: Patients that do not have an immediate response to pentobarbital coma therapy for ICH universally had poor outcomes. Alternative therapy or earlier palliation should be considered for such patients. In contrast, patients whose ICPs responded quickly to pentobarbital had excellent long-term outcomes.

The Declining Use of Opioids at a Level 1 Trauma Center.

BACKGROUND: The epidemic of opioid-related overdose in the United States prompted a public health response that included implementation of opioid prescribing guidelines and restrictions. Such directives, however, were not applicable to hospitalized trauma patients. We hypothesized that although prescribing mandates did not apply to hospitalized trauma patients, inpatient opioid administration had nonetheless decreased over time. METHODS: Opioid administrations for each patient admitted to a level I trauma center between January 1, 2016 and July 31, 2020 were converted into oral morphine milligram equivalents (MMEs) and summed at the patient level to obtain a total amount of MME administered for each hospitalization. MME was natural log transformed to achieve a normal distribution. General linear models were then used to determine the average patient MME administered by year. Patients who were pregnant or mechanically ventilated during their hospitalization were excluded. RESULTS: Six thousand five hundred ninety-four patients were included in our analysis, of which 5037 (76.4%) were treated with opioids during their hospitalization (morphine 72.7%, oxycodone 9.6%, tramadol 10.2%, fentanyl 5.5%, and hydromorphone 2.1%). The percentage of patients administered an opioid decreased stepwise from 79.3% in 2016 to 71.4% in 2020 (P < .001). For patients administered opioids, a 28% decrease in average total MME from 2016 to 2020 (P < .001) was observed. When stratified by ISS (<9, 9-15, 16+), average total MME consistently trended downward over time. CONCLUSION: Our trauma center realized a stepwise reduction in opioid administration in the absence of rules or restrictions surrounding in-hospital opioid prescribing.

Blunt pancreatic trauma: A Western Trauma Association critical decisions algorithm.

BACKGROUND: The Western Trauma Association (WTA) has undertaken publication of best practice clinical practice guidelines on multiple trauma topics. These guidelines are based on scientific evidence, case reports, and best practices per expert opinion. Some of the topics covered by this consensus group do not have the ability to have randomized controlled studies completed because of complexity, ethical issues, financial considerations, or scarcity of experience and cases. Blunt pancreatic trauma falls under one of these clinically complex and rare scenarios. This algorithm is the result of an extensive literature review and input from the WTA membership and WTA Algorithm Committee members. METHODS: Multiple evidence-based guideline reviews, case reports, and expert opinion were compiled and reviewed. RESULTS: The algorithm is attached with detailed explanation of each step, supported by data if available. CONCLUSION: Blunt pancreatic trauma is rare and presents many treatment challenges.

Pediatric emergency resuscitative thoracotomy: A Western Trauma Association, Pediatric Trauma Society, and Eastern Association for the Surgery of Trauma collaborative critical decisions algorithm.

LEVEL OF EVIDENCE: Literature synthesis and expert opinion, Level V.

Commonly performed pelvic binder modifications for femoral access may hinder binder efficacy.

BACKGROUND: Pelvic fractures are common and potentially life-threatening. Pelvic circumferential compression devices (PCCD) can temporize hemorrhage, but more invasive strategies that involve femoral access may be necessary for definitive treatment. The aim of our study was to evaluate the efficacy of PCCDs reducing open book pelvic fractures when utilizing commonly described modifications and placement adjustments that allow for access to the femoral vasculature. METHODS: Open book pelvic fractures were created in adult cadavers. Three commercially available PCCDs were used to reduce fractures. The binders were properly placed, moved caudally, or moved cranially and modified. Fracture reduction rates were then recorded. RESULTS: The pelvic fracture was completely reduced with every PCCD tested when properly placed. Reduction rates decreased with improper placement and modifications. CONCLUSION: Modifying PCCD placement to allow femoral access decreased the effectiveness of these devices Clinicians should be aware of this possibility when caring for critically injured trauma patients with pelvic fractures.

Length of stay and trauma center finances: A disparity of payer source at a Level I trauma center.

BACKGROUND: In an effort to reduce costs, hospitals focus efforts on reducing length of stay (LOS) and often benchmark LOS against the geometric LOS (GMLOS) as predicted by the assigned diagnosis-related group (DRG) used by the Centers for Medicare and Medicaid Services. The objective of this cross-sectional study was to evaluate the impact of exceeding GMLOS on hospital profit/loss with respect to payer source. METHODS: Contribution margin for each insured patient admitted to a Level I trauma center between July 1, 2016, and June 30, 2019, was determined. Age, ethnicity, race, DRG weight, DRG version, injury severity, intensive care unit admission status, mechanical ventilation, payer, exceeding GMLOS, and the interaction between payer and exceeding the GMLOS were regressed on contribution margin to determine significant predictors of positive contribution margin. RESULTS: Among 2,449 insured trauma patients, the distribution of payers was Medicaid (54.6%), Medicare (24.0%), and commercial (21.4%). Thirty-five percent (n = 867) of patient LOS exceeded GMLOS. Exceeding GMLOS by 10 or more days was significantly more likely for Medicaid and Medicare patients in stepwise fashion (commercial, 2.7%; Medicaid, 4.5%; Medicare, 6.0%; p = 0.030). Median contribution margin was positive for commercially insured patients ($16,913) and negative for Medicaid (-$8,979) and Medicare (-$2,145) patients. Adjusted multivariate modeling demonstrated that when exceeding GMLOS, Medicare and Medicaid cases were less likely than commercial payers to have a positive contribution margin (p < 0.001 and p < 0.001). CONCLUSION: Government-insured patients, despite having a payer source, are a financial burden to a trauma center. Excess LOS among government insured patients, but not the commercially insured, exacerbates financial loss. A shift toward a greater proportion of government insured patients may result in a significant fiscal liability for a trauma center. LEVEL OF EVIDENCE: Economic and Value-Based Evaluation, Level III.

Can we really make catheter-associated urinary tract infections a never event? A level 1 trauma center's experience with prophylactic antibiotic bladder irrigation.

BACKGROUND: Hospital-acquired catheter-associated urinary tract infections (CAUTIs) are considered "never events" and are reportable to Centers for Medicare and Medicaid Services as a quality indicator. Despite protocols to determine appropriate removal of urinary catheters as soon as possible, severely injured trauma patients often require prolonged catheterization during ongoing resuscitation or develop retention requiring catheter replacement, exposing them to risk for CAUTI. We evaluated whether prophylactic antibiotic bladder irrigation reduces the incidence of CAUTI in critically ill trauma patients. METHODS: As a quality initiative, gentamicin bladder catheter irrigation (GBCI) was performed on a level 1 trauma center's patients at risk for CAUTI in 2021, defined by indwelling Foley catheterization for a minimum of 3 days. We then conducted a retrospective study using a comparison cohort of 2020 admissions as the control group. Catheter-associated urinary tract infection rates per 1,000 catheterized days were compared between these two groups. Patients with traumatic bladder injuries were excluded. RESULTS: Our cohort included 342 patients with a median hospitalization of 11 (7-17) days, Injury Severity Score of 17 (10-26), and 6 (4-11) days of catheterization. Eighty-six patients, catheterized for 939 at-risk days, received twice-daily GBCI compared with 256, catheterized for 2,114 at-risk days, who did not. Zero patients in the GBCI group versus nine patients in the control group developed CAUTI. The incidence of CAUTI in the GBCI group was significantly less than in the control group (0/1,000 vs. 4.3/1,000 catheterized days, p = 0.018). CONCLUSION: Prophylactic antibiotic bladder irrigation was associated with a zero incidence of CAUTI among trauma patients at risk for CAUTI. This practice holds promise as effective infection prophylaxis for such patients. The optimal duration and frequency of irrigation remain to be determined. LEVEL OF EVIDENCE: Therapeutic/care management, Level III.

Evaluation and management of traumatic pneumothorax: A Western Trauma Association critical decisions algorithm.

ABSTRACT: This is a recommended algorithm of the Western Trauma Association for the management of a traumatic pneumothorax. The current algorithm and recommendations are based on available published prospective cohort, observational, and retrospective studies and the expert opinion of the Western Trauma Association members. The algorithm and accompanying text represents a safe and reasonable approach to this common problem. We recognize that there may be variability in decision making, local resources, institutional consensus, and patient-specific factors that may require deviation from the algorithm presented. This annotated algorithm is meant to serve as a basis from which protocols at individual institutions can be developed or serve as a quick bedside reference for clinicians. LEVEL OF EVIDENCE: Consensus algorithm from the Western Trauma Association, Level V.

Red blood cell age and potentiation of transfusion-related pathology in trauma patients.

The specific negative clinical manifestations associated with the transfusion of stored red blood cells (RBCs) and the corresponding mechanisms responsible for such phenomena remain poorly defined. Our recent studies document that leukoreduced older RBC units potentiate transfusion-related toxicity in trauma patients. It is our hypothesis that the transfusion of relatively older blood impedes microvascular perfusion. The central mechanisms proposed to mediate this microcirculatory alteration include: 1) the loss of RBC-dependent control of nitric oxide-mediated homeostasis concerning vasodilation and 2) immune cell and complement activation. In this review, we outline the background for our hypothesis and detail our current investigations toward the understanding of this pathophysiology.

Prospective identification of patients at risk for massive transfusion: an imprecise endeavor.

Most retrospective studies evaluating fresh-frozen plasma:packed red blood cell ratios in trauma patients requiring massive transfusion (MT) are limited by survival bias. As prospective resource-intensive studies are being designed to better evaluate resuscitation strategies, it is imperative that patients with a high likelihood of MT are identified early. The objective of this study was to develop a predictive model for MT in civilian trauma patients. Patients admitted to the University of Alabama at Birmingham Trauma Center from January 2005 to December 2007 were selected. Admission clinical measurements, including blood lactate 5 mMol/L or greater, heart rate greater than 105 beats/min, international normalized ratio greater than 1.5, hemoglobin 11 g/dL or less, and systolic blood pressure less than 110 mmHg, were used to create a predictive model. Sensitivity (Sens), specificity (Spec), positive predictive value (PPV), and negative predictive value (NPV) were calculated for all possible combinations of clinical measurements as well as each measure individually. A total of 6638 patients were identified, of whom 158 (2.4%) received MT. The best-fit predictive model included three or more positive clinical measures (Sens: 53%, Spec: 98%, PPV: 33%, NPV: 99%). There was increased PPV when all clinical measurements were positive (Sens: 9%, Spec: 100%, PPV: 86%, NPV: 98%). All combinations or clinical measures alone yielded lower predictive probability. Using these emergency department clinical measures, a predictive model to successfully identify civilian trauma patients at risk for MT was not able to be constructed. Given prospective identification of patients at risk for MT remains an imprecise undertaking, appropriate resources to support these efforts will need to be allocated for the completion of these studies.

Identifying risk for massive transfusion in the relatively normotensive patient: utility of the prehospital shock index.

BACKGROUND: In the prehospital environment, the failure of medical providers to recognize latent physiologic derangement in patients with compensated shock may risk undertriage. We hypothesized that the shock index (SI; heart rate divided by systolic blood pressure [SBP]), when used in the prehospital setting, could facilitate the identification of such patients. The objective of this study was to assess the association between the prehospital SI and the risk of massive transfusion (MT) in relatively normotensive blunt trauma patients. METHODS: Admissions to a Level I trauma center between January 2000 and October 2008 with blunt mechanism of injury and prehospital SBP>90 mm Hg were identified. Patients were categorized by SI, calculated for each patient from prehospital vital signs. Risk ratios (RRs) and 95% confidence intervals (CI) for requiring MT (>10 red blood cell units within 24 hours of admission) were calculated using SI>0.5 to 0.7 (normal range) as the referent for all comparisons. RESULTS: A total of 8,111 patients were identified, of whom 276 (3.4%) received MT. Compared with patients with normal SI, there was no significant increased risk for MT for patients with a SI of ≤0.5 (RR, 1.41; 95% CI, 0.90-2.21) or>0.7 to 0.9 (RR, 1.06; 95% CI, 0.77-1.45). However, a significantly increased risk for MT was observed for patients with SI>0.9. Specifically, patients with SI>0.9 to 1.1 were observed to have a 1.5-fold increased risk for MT (RR, 1.61; 95% CI, 1.13-2.31). Further increases in SI were associated with incrementally higher risks for MT, with an more than fivefold increase in patients with SI>1.1 to 1.3 (RR, 5.57; 95% CI, 3.74-8.30) and an eightfold risk in patients with SI>1.3 (RR, 8.13; 95% CI, 4.60-14.36). CONCLUSION: Prehospital SI>0.9 identifies patients at risk for MT who would otherwise be considered relatively normotensive under current prehospital triage protocols. The risk for MT rises substantially with elevation of SI above this level. Further evaluation of SI in the context of trauma system triage protocols is warranted to analyze whether it triage precision might be augmented among blunt trauma patients with SBP>90 mm Hg.