The Effect of Perfusate Temperature on Delayed Graft Function in Deceased Donor Renal Transplantation.

Introduction: Renal allograft hypothermic machine perfusion results in a decreased incidence of delayed graft function compared with static cold storage. Ensuring perfusate temperatures remain within the target range of 4-10 °C may impact delayed graft function rates. Project Aims: To identify whether this target was achieved and, if not, whether higher perfusate temperature was associated with delayed graft function. Design: In this retrospective cohort study, transplanted grafts from deceased donors placed on hypothermic machine perfusion pump from June 2019 to August 2020 were analyzed. Measurements were recovered after 5, 15, 60, and 180 min of perfusion. Univariable and multivariable analyses were performed to identify predictors of delayed graft function. Results: A total of 113 grafts from 94 donors were analyzed. Of these, 21 (19%) developed delayed graft function. On univariable logistic regression, variables associated with delayed graft function included older donor age (OR 1.08, P = .002), higher Kidney Donor Profile Index score (OR 1.03, P = .024), and higher 5-min perfusate temperature (T5 min; OR 1.49, P = .014). A higher T5 min was also associated with delayed graft function in multivariable logistic regression models (OR 1.58, P = .005; OR 1.37, P = .08). Grafts with T5 min >10 °C were more likely to experience delayed graft function than those with T5 min <10 °C (OR 4.5, P = .006). Conclusion: Higher early perfusate temperature was an independent predictor of delayed graft function and may be due to inadequate cooling of the circuit prior to placing grafts on pump. Quality improvement initiatives targeting early perfusate temperatures of ≤10 °C may reduce delayed graft function incidence.

Pediatric trauma venous thromboembolism prediction algorithm outperforms current anticoagulation prophylaxis guidelines: a pilot study.

PURPOSE: Venous thromboembolism (VTE) in injured children is rare, but sequelae can be morbid and life-threatening. Recent trauma society guidelines suggesting that all children over 15 years old should receive thromboprophylaxis may result in overtreatment. We sought to evaluate the efficacy of a previously published VTE prediction algorithm and compare it to current recommendations. METHODS: Two institutional trauma registries were queried for all pediatric (age < 18 years) patients admitted from 2007 to 2018. Clinical data were applied to the algorithm and the area under the receiver operating characteristic (AUROC) curve was calculated to test algorithm efficacy. RESULTS: A retrospective review identified 8271 patients with 30 episodes of VTE (0.36%). The VTE prediction algorithm classified 51 (0.6%) as high risk (> 5% risk), 322 (3.9%) as moderate risk (1-5% risk) and 7898 (95.5%) as low risk (< 1% risk). AUROC was 0.93 (95% CI 0.89-0.97). In our population, prophylaxis of the 'moderate-' and 'high-risk' cohorts would outperform the sensitivity (60% vs. 53%) and specificity (96% vs. 77%) of current guidelines while anticoagulating substantially fewer patients (373 vs. 1935, p < 0.001). CONCLUSION: A VTE prediction algorithm using clinical variables can identify injured children at risk for venous thromboembolic disease with more discrimination than current guidelines. Prospective studies are needed to investigate the validity of this model. LEVEL OF EVIDENCE: III-Clinical decision rule evaluated in a single population.

Conscious sedation versus rapid sequence intubation for the reduction of native traumatic hip dislocation.

BACKGROUND: Traumatic hip dislocations (THD) are a medical emergency. There is debate whether the painful reduction of a dislocated hip should be first attempted using primary conscious sedation (PCS) or primary general anesthesia (PGA) METHODS: All cases of native THD from 2006 to 2015 in the trauma registry of a level 1 trauma center were reviewed. The primary outcome was successful reduction of the THD. RESULTS: 67 patients had a native, meaning not a hip prosthesis, THD. 34 (50.7%) patients had successful PCS, 12 (17.9%) failed PCS and underwent reduction following PGA. 21 (31.3%) underwent PGA. Patients in the PGA group were more severely injured. Time to reduction greater than 6 h was associated with PCS failure (Odds ratio (95% confidence interval) 19.75 (2.06,189.10) p = 0.01). CONCLUSION: Clinicians treating patients with a THD can utilize either PCS or PGA with many patients safely reduced under PCS. However, patients whose hip have been dislocated for more than 6 h are at risk for failure with PCS, and are good candidates for PGA.

The Respiratory Rate: A Neglected Triage Tool for Pre-hospital Identification of Trauma Patients.

BACKGROUND: Under-triaged trauma patients have worse clinical outcomes. We evaluated the capability of four pre-hospital variables to identify this population at the lowest level trauma activation (level 3). METHODS: A retrospective review of adult trauma activations from 2004 to 2014 was completed. Pre-hospital vital signs and Glasgow Coma Scale were converted to categorical variables. Patients were under-triaged based on meeting current level 1 or 2 criteria, or requiring a pre-defined critical intervention. Logistic regression was used to determine the association between the pre-hospital variables and under-triaged patients. Odds ratios and 95% confidence intervals were calculated for a comprehensive model, grouping all causes of under-triage as a single unit, and 16 individual models, one for each under-triage criterion. A new level 2 criterion was generated and internally validated. RESULTS: In total, 12,332 activations occurred during the study period. Four hundred and sixty-six (5.9%) patients were under-triaged. Compared to patients with a normal respiratory rate (RR), tachypneic patients were more likely to be under-triaged for any reason, OR 1.7 [1.3-2.1], p < 0.001. In the individual event analysis, tachypneic patients were more likely to have flail chest, OR 22 [2.9-168.3], p = 0.003; require a chest tube, OR 3 [1.8-4.9], p < 0.001; or require emergent intubation, OR 1.6 [1.1-2.8], p = 0.04, compared to patients with a normal RR. The data-driven triage modification was tachypnea with suspected thoracic injury which reduced the under-triage rate by 1.2%. CONCLUSION: Tachypnea with suspected thoracic injury is the strongest level 2 triage modification to reduce level 3 under-triage.

Limiting thoracic CT: a rule for use during initial pediatric trauma evaluation.

BACKGROUND: Despite increases in imaging guidelines for other body-regions during initial trauma assessment and the demonstrated utility of chest radiographs (CXR), guidelines for use of thoracic computed-tomography (TCT) are lacking. We hypothesized that TCT utilization had not decreased relative to other protocolized CTs, and mechanism and CXR could together predict significant injury independent of TCT. METHODS: We performed a retrospective review of blunt trauma patients ≤18 y.o. (2007-2015) at two level-1 trauma centers who received chest imaging. Baseline characteristics and incidences of body region-specific CT were compared. Injury mechanism, intrathoracic pathology, and interventions among other data were examined (significance: p<0.05). RESULTS: Although other body-region CT incidence decreased (p<0.05), TCT incidence did not change (p=0.65). Of the 2951 patients, 567 had both CXR and TCT, 933 received TCT-only, and 1451 had CXR-only. TCT altered management in 17 patients: 2 operations, 1 stent-placement, 1 medical management, 9 thoracostomy tube placements, and 4 negative diagnostic workups. All clinically significant changes were predicted by vehicle-related mechanism and abnormal CXR findings. CONCLUSIONS: TCT utilization has not decreased over time. All meaningful interventions were predicted by CXR and mechanism of injury. We propose a rule, for prospective validation, reserving TCT for patients with abnormal CXR findings and severe vehicle-related trauma. LEVEL OF EVIDENCE: Diagnostic study, Level III.

Splenectomy is associated with higher infection and pneumonia rates among trauma laparotomy patients.

Splenectomy increases lifetime risk of thromboembolism (VTE) and is associated with long-term infectious complications, primarily, overwhelming post-splenectomy infection (OPSI). Our objective was to evaluate risk of VTE and infection at index hospitalization post-splenectomy. Retrospective review of all patients who received a laparotomy in the NTDB. Propensity score matching for splenectomy was performed, based on ISS, abdominal abbreviated injury score >3, GCS, sex and mechanism. Major complications, VTE, and infection rates were compared. Multiple logistic regression models were utilized to evaluate splenectomy-associated complications. 93,221 laparotomies were performed and 17% underwent splenectomy. Multiple logistic regression models did not demonstrate an association between splenectomy and major complications (OR 0.96, 95% CI 0.91-1.03, p = 0.25) or VTE (OR 1.05, 95% CI 0.96-1.14, p = 0.33). Splenectomy was independently associated with infection (OR 1.07, 95% CI 1.00-1.14, p = 0.045). Subgroup analysis of patients with infection demonstrated that splenectomy was most strongly associated with pneumonia (OR 1.41, 95% CI 1.26-1.57, p < 0.001). Splenectomy is not associated with higher overall complication or VTE rates during index hospitalization. However, splenectomy is associated with a higher rate of pneumonia.

Early analysis of laparoscopic common bile duct exploration simulation.

BACKGROUND: We developed a laparoscopic common bile duct exploration (LCBDE) simulation course for resident surgeons (RS) and practicing surgeons (PS). We hypothesized that course completion would provide LCBDE procedural skills and increase procedure utilization. METHODS: RS and PS were prospectively enrolled. Pre- and post-course ability were assessed with written examinations and LCBDE simulations. PS completed pre-course, post-course, and 1-year follow-up surveys (5-point Likert-type scale). RESULTS: 17 RS and 8 PS were enrolled. Median written test scores improved (70.0%-80.0%, p < 0.001) and median LCBDE simulation times (seconds) improved (585-314, p = 0.001) among all participants. Comparing RS and PS, median written assessment scores pre-course (70% vs 72.5%, p = 0.953) and post-course (77.5% vs 80.0%, p = 0.198) were not significantly different. Simulation completion times (seconds) improved similarly from pre-course (608.0 vs 521.5, p = 0.885) to post-course (314.0 vs 373.0, p = 0.287) between groups. PS comfort with LCBDE improved (2-4, p = 0.03). All PS reported LCBDE utilization 1 year post-course. CONCLUSIONS: The LCBDE course is appropriate for RS and PS. PS also reported increased comfort with LCBDE and procedure utilization.

Optimizing physician skill development for medical students: The four-part assessment.

BACKGROUND: Medical student performance has been poorly correlated with residency performance and warrants further investigation. We propose a novel surgical assessment tool to determine correlations with clinical aptitude. METHODS: Retrospective review of medical student assessments from 2013 to 2015. Faculty rating of student performance was evaluated by: 1) case presentation, 2) problem definition, 3) question response and 4) use of literature and correlated to final exam assessment. A Likert scale interrater reliability was evaluated. RESULTS: Sixty student presentations were scored (4.8 assessors/presentation). A student's case presentation, problem definition, and question response was correlated with performance (r = 0.49 to 0.61, p ≤ 0.003). Moderate correlations for either question response or use of literature was demonstrated (0.3 and 0.26, p < 0.05). CONCLUSION: Our four-part assessment tool identified correlations with course and examination grades for medical students. As surgical education evolves, validated performance and reliable testing measures are required.

Onset of Coagulation Function Recovery Is Delayed in Severely Injured Trauma Patients with Venous Thromboembolism.

BACKGROUND: Altered coagulation function after trauma can contribute to development of venous thromboembolism (VTE). Severe trauma impairs coagulation function, but the trajectory for recovery is not known. We hypothesized that enhanced, early recovery of coagulation function increases VTE risk in severely injured trauma patients. STUDY DESIGN: Secondary analysis was performed on data from the Pragmatic Randomized Optimal Platelet and Plasma Ratio (PROPPR) trial, excluding patients who died within 24 hours or were on pre-injury anticoagulants. Patient characteristics, adverse outcomes, and parameters of platelet function and coagulation (thromboelastography) were compared from admission to 72 hours between VTE (n = 83) and non-VTE (n = 475) patients. A p value < 0.05 indicates significance. RESULTS: Despite similar patient demographics, VTE patients exhibited hypercoagulable thromboelastography parameters and enhanced platelet function at admission (p < 0.05). Both groups exhibited hypocoagulable thromboelastography parameters, platelet dysfunction, and suppressed clot lysis (low clot lysis at 30 minutes) 2 hours after admission (p < 0.05). The VTE patients exhibited delayed coagulation recovery (a significant change compared with 2 hours) of K-value (48 vs 24 hours), α-angle (no recovery), maximum amplitude (24 vs 12 hours), and clot lysis at 30 minutes (48 vs 12 hours). Platelet function recovery mediated by arachidonic acid (72 vs 4 hours), ADP (72 vs 12 hours), and collagen (48 vs 12 hours) was delayed in VTE patients. The VTE patients had lower mortality (4% vs 13%; p < 0.05), but fewer hospital-free days (0 days [interquartile range 0 to 8 days] vs 10 days [interquartile range 0 to 20 days]; p < 0.05) and higher complication rates (p < 0.05). CONCLUSIONS: Recovery from platelet dysfunction and coagulopathy after severe trauma were delayed in VTE patients. Suppressed clot lysis and compensatory mechanisms associated with altered coagulation that can potentiate VTE formation require additional investigation.

Damage control laparotomy utilization rates are highly variable among Level I trauma centers: Pragmatic, Randomized Optimal Platelet and Plasma Ratios findings.

BACKGROUND: Damage control laparotomy (DCL) is intended to limit deleterious effects from trauma-induced coagulopathy. DCL has been associated with mortality reduction, but may increase complications including sepsis, abscess, respiratory failure, hernia, and gastrointestinal fistula. We hypothesized that (1) DCL incidence would vary between institutions; (2) mortality rates would vary with DCL rates; (3) standard DCL criteria of pH, international normalized ratio, temperature and major intra-abdominal vascular injury would not adequately capture all patients. METHODS: Trauma patients at 12 Level 1 North American trauma centers were randomized based on transfusion ratios as described in the Pragmatic, Randomized Optimal Platelet and Plasma Ratios trial. We analyzed outcomes after emergent laparotomy using a mixed-effects logistic model comparing DCL versus definitive surgical management with random effect for study site. Primary outcomes were 24-hour and 30-day mortality. RESULTS: Three hundred twenty-nine patients underwent emergent laparotomy: 213 (65%) DCL and 116 (35%) definitive surgical management. DCL rates varied between institutions (33-83%), (p = 0.002). Median Injury Severity Score (ISS) was higher in the DCL group, 29 (interquartile range, 13-34) versus 21 (interquartile range, 22-41) (p < 0.001). Twenty-four-hour mortality was 19% with DCL versus 4% (p < 0.001); 30-day mortality was 28% with DCL versus 19% (p < 0.001). In a mixed-effects model, ISS and major intra-abdominal vascular injury were correlates of DCL (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.02-1.07 and OR, 2.7; 95% CI, 1.4-5.2). DCL was not associated with 30-day mortality (OR, 2.33; 95% CI, 0.97-5.60). Correlates included ISS (OR, 1.06; 95% CI, 1.02-1.09), PRBCs in 24 hours (OR, 1.10; 95% CI, 1.03-1.18), and age (OR, 1.04; 95% CI, 1.01-1.06). No significant mortality difference was detected between institutions (p = 0.63). Sepsis and VAP occurred more frequently with DCL (p < 0.05). Eighty percent (135/213) of DCL patients met standard criteria. CONCLUSION: Although DCL utilization varied significantly between institutions, there was no significant mortality difference between centers. This finding suggests tempering DCL use may not decrease mortality, but could decrease related complications. LEVEL OF EVIDENCE: Therapeutic study, level III.

Thrombelastography-Based Dosing of Enoxaparin for Thromboprophylaxis in Trauma and Surgical Patients: A Randomized Clinical Trial.

Importance: Prophylactic enoxaparin is used to prevent venous thromboembolism (VTE) in surgical and trauma patients. However, VTE remains an important source of morbidity and mortality, potentially exacerbated by antithrombin III or anti-Factor Xa deficiencies and missed enoxaparin doses. Recent data suggest that a difference in reaction time (time to initial fibrin formation) greater than 1 minute between heparinase and standard thrombelastogram (TEG) is associated with a decreased risk of VTE. Objective: To evaluate the effectiveness of TEG-adjusted prophylactic enoxaparin dosing among trauma and surgical patients. Design, Setting, and Participants: This randomized clinical trial, conducted from October 2012 to May 2015, compared standard dosing (30 mg twice daily) with TEG-adjusted enoxaparin dosing (35 mg twice daily) for 185 surgical and trauma patients screened for VTE at 3 level I trauma centers in the United States. Main Outcomes and Measures: The incidence of VTE, bleeding complications, anti-Factor Xa deficiency, and antithrombin III deficiency. Results: Of the 185 trial participants, 89 were randomized to the control group (median age, 44.0 years; 55.1% male) and 96 to the intervention group (median age, 48.5 years; 74.0% male). Patients in the intervention group received a higher median enoxaparin dose than control patients (35 mg vs 30 mg twice daily; P < .001). Anti-Factor Xa levels in intervention patients were not higher than levels in control patients until day 6 (0.4 U/mL vs 0.21 U/mL; P < .001). Only 22 patients (11.9%) achieved a difference in reaction time greater than 1 minute, which was similar between the control and intervention groups (10.4% vs 13.5%; P = .68). The time to enoxaparin initiation was similar between the control and intervention groups (median [range] days, 1.0 [0.0-2.0] vs 1.0 [1.0-2.0]; P = .39), and the number of patients who missed at least 1 dose was also similar (43 [48.3%] vs 54 [56.3%]; P = .30). Rates of VTE (6 [6.7%] vs 6 [6.3%]; P > .99) were similar, but the difference in bleeding complications (5 [5.6%] vs 13 [13.5%]; P = .08) was not statistically significant. Antithrombin III and anti-Factor Xa deficiencies and hypercoagulable TEG parameters, including elevated coagulation index (>3), maximum amplitude (>74 mm), and G value (>12.4 dynes/cm2), were prevalent in both groups. Identified risk factors for VTE included older age (61.0 years vs 46.0 years; P = .04), higher body mass index (calculated as weight in kilograms divided by height in meters squared; 30.6 vs 27.1; P = .03), increased Acute Physiology and Chronic Health Evaluation II score (8.5 vs 7.0; P = .03), and increased percentage of missed doses per patient (14.8% vs 2.5%; P = .05). Conclusions and Relevance: The incidence of VTE was low and similar between groups; however, few patients achieved a difference in reaction time greater than 1 minute. Antithrombin III deficiencies and hypercoagulable TEG parameters were prevalent among patients with VTE. Low VTE incidence may be due to an early time to enoxaparin initiation and an overall healthier and less severely injured study population than previously reported. Trial Registration: clinicaltrials.gov Identifier: NCT00990236.

Performance improvement and patient safety program-guided quality improvement initiatives can significantly reduce computed tomography imaging in pediatric trauma patients.

BACKGROUND: Morbidity and mortality of cervical spine (C-spine) injury in pediatric trauma patients are high, necessitating quick and accurate diagnosis. Best practices emphasize minimizing radiation exposure through decreased reliance on computed tomography (CT), instead using clinical assessment, physical examination, and alternate imaging techniques. We implemented an institutional performance improvement and patient safety (PIPS) program initiative for C-spine clearance in 2010 because of high rates of CT scans among pediatric trauma patients. METHODS: A retrospective review of pediatric trauma patients, aged 0 years to 14 years, in the pre- and post-PIPS implementation periods was conducted. Rates of C-spine CT, overall CT, other imaging modalities, radiation exposure, patient characteristics, and injury severity were compared, and compliance with PIPS protocol was reviewed. RESULTS: Patient characteristics and injury severity were similar before and after PIPS implementation. C-spine CT rates decreased significantly between groups (30% vs. 13%, p < 0.001), whereas C-spine plain x-ray rates increased significantly (7% vs. 25%, p < 0.001). There was no difference in C-spine magnetic resonance imaging between groups (12% vs. 10%, p = 0.11). In 2007, 71% of patients received a CT scan for any reason. However, the overall CT rate decreased significantly between groups (60% vs. 45%, p < 0.001). There was an estimated 22% decrease in lifetime attributable risk (LAR) for any cancer due to ionizing imaging exposure in males and 38% decrease in females between the pre- and post-PIPS groups. There was a 54% decrease in LAR for thyroid cancer in males and females between groups; 2014 compliance with the protocol was excellent (82-90% per quarter). CONCLUSIONS: Performance improvement and patient safety program-generated protocol can significantly decrease ionizing radiation exposure. We demonstrate that a simple protocol focused on C-spine imaging has high compliance, decreased C-spine CT scans, and decreased LAR for thyroid cancer. A secondary benefit is a reduction in total CT imaging, with an associated decrease in LAR for all cancers. LEVEL OF EVIDENCE: Therapeutic study, level IV; diagnostic study, level III.

A night float week in a surgical clerkship improves student team cohesion.

BACKGROUND: We hypothesize that night float rotations in the third-year surgical clerkship improve student learning and perceptions of team cohesion. METHODS: A 1-week night float (NF) system was implemented during the 2013 to 2014 academic year for students. Each student completed 1 week of NF with the Trauma/Emergency General Surgery service. The Perceived Cohesion Scale survey was prospectively administered and National Board of Medical Examiners academic performance retrospectively reviewed. RESULTS: We surveyed 70 medical students, 37 traditional call and 33 NF students, with 91% response rate. Perception of team cohesion increased significantly, without perceived loss of educational benefit. Examination scores increased significantly comparing pre- and postintervention groups, with this trend continuing in the following academic year. CONCLUSIONS: A week-long student NF experience significantly improved perception of team cohesion and standardized examination results. A dedicated period of NF during the surgical clerkship may improve its overall educational value.

A Clinical Tool for the Prediction of Venous Thromboembolism in Pediatric Trauma Patients.

IMPORTANCE: Although rare, the incidence of venous thromboembolism (VTE) in pediatric trauma patients is increasing, and the consequences of VTE in children are significant. Studies have demonstrated increasing VTE risk in older pediatric trauma patients and improved VTE rates with institutional interventions. While national evidence-based guidelines for VTE screening and prevention are in place for adults, none exist for pediatric patients, to our knowledge. OBJECTIVES: To develop a risk prediction calculator for VTE in children admitted to the hospital after traumatic injury to assist efforts in developing screening and prophylaxis guidelines for this population. DESIGN, SETTING, AND PARTICIPANTS: Retrospective review of 536,423 pediatric patients 0 to 17 years old using the National Trauma Data Bank from January 1, 2007, to December 31, 2012. Five mixed-effects logistic regression models of varying complexity were fit on a training data set. Model validity was determined by comparison of the area under the receiver operating characteristic curve (AUROC) for the training and validation data sets from the original model fit. A clinical tool to predict the risk of VTE based on individual patient clinical characteristics was developed from the optimal model. MAIN OUTCOME AND MEASURE: Diagnosis of VTE during hospital admission. RESULTS: Venous thromboembolism was diagnosed in 1141 of 536,423 children (overall rate, 0.2%). The AUROCs in the training data set were high (range, 0.873-0.946) for each model, with minimal AUROC attenuation in the validation data set. A prediction tool was developed from a model that achieved a balance of high performance (AUROCs, 0.945 and 0.932 in the training and validation data sets, respectively; P = .048) and parsimony. Points are assigned to each variable considered (Glasgow Coma Scale score, age, sex, intensive care unit admission, intubation, transfusion of blood products, central venous catheter placement, presence of pelvic or lower extremity fractures, and major surgery), and the points total is converted to a VTE risk score. The predicted risk of VTE ranged from 0.0% to 14.4%. CONCLUSIONS AND RELEVANCE: We developed a simple clinical tool to predict the risk of developing VTE in pediatric trauma patients. It is based on a model created using a large national database and was internally validated. The clinical tool requires external validation but provides an initial step toward the development of the specific VTE protocols for pediatric trauma patients.

Endpoints in resuscitation.

PURPOSE OF REVIEW: Shock occurs because of a failure to deliver adequate oxygen to meet the metabolic demands of the body resulting in metabolic acidosis, inflammation, and coagulopathy. Resuscitation is the process of treating shock in an attempt to restore normal physiology. Various hemodynamic, metabolic, and regional endpoints have been described to evaluate the degree of shock and guide resuscitation efforts. We will briefly describe these endpoints, and propose damage control resuscitation as an additional endpoint. RECENT FINDINGS: Serum lactate, base deficit, and pH are well established endpoints of resuscitation that provide valuable information when trended over time; however, a single value is inadequate to determine adequacy of resuscitation. Rapid normalization of central venous oxygen concentration has been associated with improved survival, and bedside transthoracic echocardiography can be a reliable assessment of volume status. In hypovolemic/hemorrhagic shock, early hypotensive, or controlled resuscitation strategies have been associated with improved survival, and hemostatic strategies guided by thrombelastography using a balanced transfusion approach result in improved hemostasis. SUMMARY: Numerous endpoints are available; however, no single endpoint is universally applicable. Damage control resuscitation strategies have demonstrated improved survival, hemostasis, and less early death from exsanguination, suggesting that hemorrhage control should be an additional endpoint in resuscitation.