Optimal dose of cryoprecipitate in massive transfusion following trauma.

BACKGROUND: While cryoprecipitate (Cryo) is commonly included in massive transfusion protocols for hemorrhagic shock, the optimal dose of Cryo transfusion remains unknown. We evaluated the optimal red blood cell (RBC) to RBC to Cryo ratio during resuscitation in massively transfused trauma patients. METHODS: Adult patients in the American College of Surgeon Trauma Quality Improvement Program (2013-2019) receiving massive transfusion (≥4 U of RBCs, ≥1 U of fresh frozen plasma, and ≥1 U of platelets within 4 hours) were included. A unit of Cryo was defined as a pooled unit of 100 mL. The RBC:Cryo ratio was calculated for blood products transfused within 4 hours of presentation. The association between RBC:Cryo and 24-hour mortality was analyzed with multivariable logistic regression adjusting for the volume of RBC, plasma and platelet transfusions, global and regional injury severity, and other relevant variables. RESULTS: The study cohort included 12,916 patients. Among those who received Cryo (n = 5,511 [42.7%]), the median RBC and Cryo transfusion volume within 4 hours was 11 U (interquartile range, 7-19 U) and 2 U (interquartile range, 1-3 U), respectively. Compared with no Cryo administration, only RBC:Cryo ratios ≤8:1 were associated with a significant survival benefit, while lower doses of Cryo (RBC:Cryo >8:1) were not associated with decreased 24-hour mortality. Compared with the maximum dose of Cryo administration (RBC:Cryo, 1:1-2:1), there was no difference in 24-hour mortality up to RBC:Cryo of 7:1 to 8:1, whereas lower doses of Cryo (RBC:Cryo, >8:1) were associated with significantly increased 24-hour mortality. CONCLUSION: One pooled unit of Cryo (100 mL) per 7 to 8 U of RBCs could be the optimal dose of Cryo in trauma resuscitation that provides a significant survival benefit while avoiding unnecessary blood product transfusions. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level IV.

Trauma patients with limited English proficiency: Outcomes from two level one trauma centers.

BACKGROUND: Outcomes for surgical patients with limited English proficiency (LEP) may be worse compared to patients with English proficiency. We sought to evaluate the association of LEP with outcomes for trauma patients. METHODS: Admitted adult patients on trauma service at two Level One trauma centers from 2015 to 2019 were identified. RESULTS: 12,562 patients were included in total; 7.3% had LEP. On multivariable analyses, patients with LEP had lower odds of discharge to post-acute care versus home compared to patients with English proficiency (OR 0.69; 95% CI 0.58-0.83; p < 0.001) but had similar length of stay (Beta coefficient 1.16; 95% CI 0.00-2.32; p = 0.05), and 30-day readmission (OR 1.08; 95% CI 0.87-1.35; p = 0.46). CONCLUSIONS: Trauma patients with LEP had comparable short-term outcomes to English proficient patients but were less likely to be discharged to post-acute care facilities. The role of structural barriers, family preferences, and other factors merit future investigation.

Prehospital extremity tourniquet placements-performance evaluation of non-EMS placement of a lifesaving device.

BACKGROUND: The education of civilians and first responders in prehospital tourniquet (PT) utilization has spread rapidly. We aimed to describe trends in emergency medical services (EMS) and non-EMS PT utilization, and their ability to identify proper clinical indications and to appropriately apply tourniquets in the field. METHODS: A retrospective cohort study was conducted to evaluate all adult patients with PTs who presented at two Level I trauma centers between January 2015 and December 2019. Data were collected via an electronic patient query tool and cross-referenced with institutional Trauma Registries. Medically trained abstractors determined if PTs were clinically indicated (limb amputation, vascular hard signs, injury requiring hemostasis procedure, or significant documented blood loss). PTs were further designated as appropriately or inappropriately applied (based on tourniquet location, venous tourniquet, greater than 2-h ischemic time). Descriptive statistics and univariate analyses were performed. RESULTS: 146 patients met inclusion criteria. The incidence of yearly PT placements increased between 2015 and 2019, with an increase in placement by non-EMS personnel (police, firefighter, bystander, and patient). Improvised PTs were frequently utilized by bystanders and patients, whereas first responders had high rates of commercial tourniquet use. A high proportion of tourniquets were placed without indication (72/146, 49%); however, the proportion of PTs placed without a proper indication across applier groups was not statistically different (p = 0.99). Rates of inappropriately applied PTs ranged from 21 to 46% across all groups applying PTs. CONCLUSIONS: PT placement was increasingly performed by non-EMS personnel. Present data indicate that non-EMS persons applied PTs at a similar performance level of those applied by EMS. Study LevelLevel III.

Do not forget the platelets: The independent impact of red blood cell to platelet ratio on mortality in massively transfused trauma patients.

BACKGROUND: Balanced blood component administration during massive transfusion is standard of care. Most literature focuses on the impact of red blood cell (RBC)/fresh frozen plasma (FFP) ratio, while the value of balanced RBC:platelet (PLT) administration is less established. The aim of this study was to evaluate and quantify the independent impact of RBC:PLT on 24-hour mortality in trauma patients receiving massive transfusion. METHODS: Using the 2013 to 2018 American College of Surgeons Trauma Quality Improvement Program database, adult patients who received massive transfusion (≥10 U of RBC/24 hours) and ≥1 U of RBC, FFP, and PLT within 4 hours of arrival were retrospectively included. To mitigate survival bias, only patients with consistent RBC:PLT and RBC:FFP ratios between 4 and 24 hours were analyzed. Balanced FFP or PLT transfusions were defined as having RBC:PLT and RBC:FFP of ≤2, respectively. Multivariable logistic regression was used to compare the independent relationship between RBC:FFP, RBC:PLT, balanced transfusion, and 24-hour mortality. RESULTS: A total of 9,215 massive transfusion patients were included. The number of patients who received transfusion with RBC:PLT >2 (1,942 [21.1%]) was significantly higher than those with RBC:FFP >2 (1,160 [12.6%]) (p < 0.001). Compared with an RBC:PLT ratio of 1:1, a gradual and consistent risk increase was observed for 24-hour mortality as the RBC:PLT ratio increased (p < 0.001). Patients with both FFP and PLT balanced transfusion had the lowest adjusted risk for 24-hour mortality. Mortality increased as resuscitation became more unbalanced, with higher odds of death for unbalanced PLT (odds ratio, 2.48 [2.18-2.83]) than unbalanced FFP (odds ratio, 1.66 [1.37-1.98]), while patients who received both FFP and PLT unbalanced transfusion had the highest risk of 24-hour mortality (odds ratio, 3.41 [2.74-4.24]). CONCLUSION: Trauma patients receiving massive transfusion significantly more often have unbalanced PLT rather than unbalanced FFP transfusion. The impact of unbalanced PLT transfusion on 24-hour mortality is independent and potentially more pronounced than unbalanced FFP transfusion, warranting serious system-level efforts for improvement. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Risk factors for ischemic gastrointestinal complications in patients undergoing open cardiac surgical procedures: A single-center retrospective experience.

BACKGROUND: Ischemic gastrointestinal complications (IGIC) following cardiac surgery are associated with high morbidity and mortality and remain difficult to predict. We evaluated perioperative risk factors for IGIC in patients undergoing open cardiac surgery. METHODS: All patients that underwent an open cardiac surgical procedure at a tertiary academic center between 2011 and 2017 were included. The primary outcome was IGIC, defined as acute mesenteric ischemia necessitating a surgical intervention or postoperative gastrointestinal bleeding that was proven to be of ischemic etiology and necessitated blood product transfusion. A backward stepwise regression model was constructed to identify perioperative predictors of IGIC. RESULTS: Of 6862 patients who underwent cardiac surgery during the study period, 52(0.8%) developed IGIC. The highest incidence of IGIC (1.9%) was noted in patients undergoing concomitant coronary artery, valvular, and aortic procedures. The multivariable regression identified hypertension (odds ratio [OR] = 5.74), preoperative renal failure requiring dialysis (OR = 3.62), immunocompromised status (OR = 2.64), chronic lung disease (OR = 2.61), and history of heart failure (OR = 2.03) as independent predictors for postoperative IGIC. Pre- or intraoperative utilization of intra-aortic balloon pump or catheter-based assist devices (OR = 4.54), intraoperative transfusion requirement of >4 RBC units(OR = 2.47), and cardiopulmonary bypass > 180 min (OR = 2.28) were also identified as independent predictors for the development of IGIC. CONCLUSIONS: We identified preoperative and intraoperative risk factors that independently increase the risk of developing postoperative IGIC after cardiac surgery. A high index of suspicion must be maintained and any deviation from the expected recovery course in patients with the above-identified risk factors should trigger an immediate evaluation with the involvement of the acute care surgical team.

The Role of Transaminases in Predicting Choledocholithiasis. A Novel Predictive Composite Score Development in a Cohort of 1089 Patients Undergoing Laparoscopic Cholecystectomy.

BACKGROUND: Optimal use of interventional procedures and diagnostic tests for patients with suspected choledocholithiasis depends on accurate pretest risk estimation. We sought to define sensitivity/specificity of transaminases in identifying choledocholithiasis and to incorporate them into a biochemical marker composite score that could accurately predict choledocholithiasis. METHODS: All adult patients who underwent laparoscopic cholecystectomy by our Emergency Surgery Service between 2010 and 2018 were reviewed. Admission total bilirubin (TB), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) was captured. Choledocholithiasis was confirmed via intraoperative cholangiogram, endoscopic retrograde cholangiopancreatography, or magnetic resonance cholangiopancreatography. Area under receiver operating characteristic curve (AUC) or C-statistic for AST, ALT, ALP, and TB as a measure of detecting choledocholithiasis was calculated. For score development, our database was randomly dichotomized to derivation and validation cohort and a score was derived. The score was validated by calculating its C-statistic. RESULTS: 1089 patients were included; 210 (20.3%) had confirmed choledocholithiasis. The AUC was .78 for TB, .77 for ALP and AST, and .76 for ALT. 545 and 544 patients were included in the derivation and the validation cohort, respectively. The elements of the derived score were TB, AST, and ALP. The score ranged from 0 to 4. The AUC was .82 in the derivation and .77 in the validation cohort. The probability of choledocholithiasis increased from 8% to 89% at scores 0 to 4, respectively. CONCLUSIONS: Aspartate aminotransferase predicted choledocholithiasis adequately and should be featured in choledocholithiasis screening algorithms. We developed a biochemical composite score, shown to be accurate in preoperative choledocholithiasis risk assessment in an emergency surgery setting.

Peri-operative blood transfusion and risk of infectious complications following intestinal-cutaneous fistula surgical repair: A retrospective nationwide analysis.

BACKGROUND: Peri-operative blood transfusion (BT) may lead to transfusion-induced immunomodulation. We aimed to investigate the association between peri-operative BT and infectious complications in patients undergoing intestinal-cutaneous fistulas (ICF) repair. METHODS: We queried the ACS-NSQIP 2006-2017 database to include patients who underwent ICF repair. The main outcome was 30-day infectious complications. Univariate and multivariable logistic regression analyses were performed to assess the predictors of post-operative infections. RESULTS: Of 4,197 patients included, 846 (20.2%) received peri-operative BT. Transfused patients were generally older, sicker and had higher ASA (III-V). After adjusting for relevant covariates, patients who received intra and/or post-operative (and not pre-operative) BT had higher odds of infectious complications compared (OR = 1.22, 95% CI 1.01-1.48). Specifically, they had higher odds of organ-space surgical site infection (OR = 1.61, 95% CI 1.21-2.13), but not other infectious complications. CONCLUSIONS: Intra and/or post-operative (and not pre-operative) BT is an independent predictor of infectious complications in ICF repair.

Prehospital end-tidal carbon dioxide is predictive of death and massive transfusion in injured patients: An Eastern Association for Surgery of Trauma multicenter trial.

BACKGROUND: Prehospital identification of the injured patient likely to require emergent care remains a challenge. End-tidal carbon dioxide (ETCO2) has been used in the prehospital setting to monitor respiratory physiology and confirmation of endotracheal tube placement. Low levels of ETCO2 have been demonstrated to correlate with injury severity and mortality in a number of in-hospital studies. We hypothesized that prehospital ETCO2 values would be predictive of mortality and need for massive transfusion (MT) in intubated patients. METHODS: This was a retrospective multicenter trial with 24 participating centers. Prehospital, emergency department, and hospital values were collected. Receiver operating characteristic curves were created and compared. Massive transfusion defined as >10 U of blood in 6 hours or death in 6 hours with at least 1 U of blood transfused. RESULTS: A total of 1,324 patients were enrolled. ETCO2 (area under the receiver operating characteristic curve [AUROC], 0.67; confidence interval [CI], 0.63-0.71) was better in predicting mortality than shock index (SI) (AUROC, 0.55; CI, 0.50-0.60) and systolic blood pressure (SBP) (AUROC, 0.58; CI, 0.53-0.62) (p < 0.0005). Prehospital lowest ETCO2 (AUROC, 0.69; CI, 0.64-0.75), SBP (AUROC, 0.75; CI, 0.70-0.81), and SI (AUROC, 0.74; CI, 0.68-0.79) were all predictive of MT. Analysis of patients with normotension demonstrated lowest prehospital ETCO2 (AUROC, 0.66; CI, 0.61-0.71), which was more predictive of mortality than SBP (AUROC, 0.52; CI, 0.47-0.58) or SI (AUROC, 0.56; CI, 0.50-0.62) (p < 0.001). Lowest prehospital ETCO2 (AUROC, 0.75; CI, 0.65-0.84), SBP (AUROC, 0.63; CI, 0.54-0.74), and SI (AUROC, 0.64; CI, 0.54-0.75) were predictive of MT in normotensive patients. ETCO2 cutoff for MT was 26 mm Hg. The positive predictive value was 16.1%, and negative predictive value was high at 98.1%. CONCLUSION: Prehospital ETCO2 is predictive of mortality and MT. ETCO2 outperformed traditional measures such as SBP and SI in the prediction of mortality. ETCO2 may outperform traditional measures in predicting need for transfusion in occult shock. LEVEL OF EVIDENCE: Diagnostic test, level III.

National adherence to the ASGE-SAGES guidelines for managing suspected choledocholithiasis: An EAST multicenter study.

BACKGROUND: The American Society for Gastrointestinal Endoscopy and Society of American Gastrointestinal and Endoscopic Surgeons provide guidelines for managing suspected common bile duct (CBD) stones. We sought to evaluate adherence to the guidelines among patients with choledocholithiasis and/or acute biliary pancreatitis (ABP) and to evaluate the ability of these guidelines to predict choledocholithiasis. METHODS: We prospectively identified patients undergoing same-admission cholecystectomy for choledocholithiasis and/or ABP from 2016 to 2019 at 12 United States medical centers. Predictors of suspected CBD stones were very strong (CBD stone on ultrasound; bilirubin >4 mg/dL), strong (CBD > 6 mm; bilirubin ≥1.8 to ≤4 mg/dL), or moderate (abnormal liver function tests other than bilirubin; age >55 years; ABP). Patients were grouped by probability of CBD stones: high (any very strong or both strong predictors), low (no predictors), or intermediate (any other predictor combination). The management of each probability group was compared with the recommended management in the guidelines. RESULTS: The cohort was comprised of 844 patients. High-probability patients had 64.3% (n = 238/370) deviation from guidelines, intermediate-probability patients had 29% (n = 132/455) deviation, and low-probability patients had 78.9% (n = 15/19) deviation. Acute biliary pancreatitis increased the odds of deviation for the high- (odds ratio [OR], 1.71; 95% confidence interval [CI], 1.06-2.8; p = 0.03) and intermediate-probability groups (OR, 1.6; 95% CI, 1.07-2.42; p = 0.02). Age older than 55 years (OR, 2.19; 95% CI, 1.4-3.43; p < 0.001) also increased the odds of deviation for the intermediate group. A CBD greater than 6 mm predicted choledocholithiasis in the high (adjusted OR (aOR), 2.16; 95% CI, 1.17-3.97; p = 0.01) and intermediate group (aOR, 2.78; 95% CI, 1.59-4.86; p < 0.001). Any very strong predictor (aOR, 2.43; 95% CI, 1.76-3.37; p < 0.0001) and both strong predictors predicted choledocholithiasis (aOR, 2; 95% CI, 1.35-2.96; p < 0.001). CONCLUSION: Almost 45% of patients with suspected CBD stones were managed discordantly from the American Society for Gastrointestinal Endoscopy and Society of American Gastrointestinal and Endoscopic Surgeons guidelines. We believe these guidelines warrant revision to better reflect the ability of the clinical variables at predicting choledocholithiasis. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Early versus late enteral nutrition in critically ill patients receiving vasopressor support.

BACKGROUND: Outcomes of early enteral nutrition (EEN) in critically ill patients on vasoactive medications remain unclear. We aimed to compare in-hospital outcomes for EEN vs late EN (LEN) in mechanically ventilated patients receiving vasopressor support. METHODS: This was a retrospective study using the national eICU Collaborative Research Database. Adult patients requiring vasopressor support and mechanical ventilation within 24 h of admission and for ≥2 days were included. Patients with an admission diagnosis that could constitute a contraindication for EEN (eg, gastrointestinal [GI] perforation, GI surgery) and patients with an intensive care unit (ICU) length of stay (LOS) <72 h were excluded. EEN and LEN were defined as tube feeding within 48 h and between 48 h and 1 week (nothing by mouth during the first 48 h) of admission, respectively. Propensity score matching was performed to derive two cohorts receiving EEN and LEN that were comparable for baseline patient characteristics. RESULTS: Among 1701 patients who met the inclusion criteria (EEN: 1001, LEN: 700), 1148 were included in propensity score-matched cohorts (EEN: 574, LEN: 574). Median time to EN was 29 vs 79 h from admission in the EEN and LEN groups, respectively. There was no significant difference in mortality or hospital LOS between the two nutrition strategies. EEN was associated with shorter ICU LOS, lower need for renal replacement therapy, and lower incidence of electrolyte abnormalities. CONCLUSION: This study showed no difference in 28-day mortality between EEN and LEN in critically ill patients receiving vasopressor support.

Bowel Ischemia in COVID-19 Infection: One-Year Surgical Experience.

BACKGROUND: COVID-19 is a deadly multisystemic disease, and bowel ischemia, the most consequential gastrointestinal manifestation, remains poorly described. Our goal is to describe our institution's surgical experience with management of bowel ischemia due to COVID-19 infection over a one-year period. METHODS: All patients admitted to our institution between March 2020 and March 2021 for treatment of COVID-19 infection and who underwent exploratory laparotomy with intra-operative confirmation of bowel ischemia were included. Data from the medical records were analyzed. RESULTS: Twenty patients were included. Eighty percent had a new or increasing vasopressor requirement, 70% had abdominal distension, and 50% had increased gastric residuals. Intra-operatively, ischemia affected the large bowel in 80% of cases, the small bowel in 60%, and both in 40%. Sixty five percent had an initial damage control laparotomy. Most of the resected bowel specimens had a characteristic appearance at the time of surgery, with a yellow discoloration, small areas of antimesenteric necrosis, and very sharp borders. Histologically, the bowel specimens frequently have fibrin thrombi in the small submucosal and mucosal blood vessels in areas of mucosal necrosis. Overall mortality in this cohort was 33%. Forty percent of patients had a thromboembolic complication overall with 88% of these developing a thromboembolic phenomenon despite being on prophylactic pre-operative anticoagulation. CONCLUSION: Bowel ischemia is a potentially lethal complication of COVID-19 infection with typical gross and histologic characteristics. Suspicious clinical features that should trigger surgical evaluation include a new or increasing vasopressor requirement, abdominal distension, and intolerance of gastric feeds.

Association Between NEDD4L Variation and the Genetic Risk of Acute Appendicitis: A Multi-institutional Genome-Wide Association Study.

Importance: The familial aspect of acute appendicitis (AA) has been proposed, but its hereditary basis remains undetermined. Objective: To identify genomic variants associated with AA. Design, Setting, and Participants: This genome-wide association study, conducted from June 21, 2019, to February 4, 2020, used a multi-institutional biobank to retrospectively identify patients with AA across 8 single-nucleotide variation (SNV) genotyping batches. The study also examined differential gene expression in appendiceal tissue samples between patients with AA and controls using the GSE9579 data set in the National Institutes of Health's Gene Expression Omnibus repository. Statistical analysis was conducted from October 1, 2019, to February 4, 2020. Main Outcomes and Measures: Single-nucleotide variations with a minor allele frequency of 5% or higher were tested for association with AA using a linear mixed model. The significance threshold was set at P = 5 × 10-8. Results: A total of 29 706 patients (15 088 women [50.8%]; mean [SD] age at enrollment, 60.1 [17.0] years) were included, 1743 of whom had a history of AA. The genomic inflation factor for the cohort was 1.003. A previously unknown SNV at chromosome 18q was found to be associated with AA (rs9953918: odds ratio, 0.99; 95% CI, 0.98-1.00; P = 4.48 × 10-8). This SNV is located in an intron of the NEDD4L gene. The heritability of appendicitis was estimated at 30.1%. Gene expression data from appendiceal tissue donors identified NEDD4L to be among the most differentially expressed genes (14 of 22 216 genes; ß [SE] = -2.71 [0.44]; log fold change = -1.69; adjusted P = .04). Conclusions and Relevance: This study identified SNVs within the NEDD4L gene as being associated with AA. Nedd4l is involved in the ubiquitination of intestinal ion channels and decreased Nedd4l activity may be implicated in the pathogenesis of AA. These findings can improve the understanding of the genetic predisposition to and pathogenesis of AA.

The Emergency Surgery Score is a powerful predictor of outcomes across multiple surgical specialties: Results of a retrospective nationwide analysis.

BACKGROUND: The Emergency Surgery Score was recently validated in a prospective multicenter study as an accurate predictor of mortality in emergency general surgery patients. The Emergency Surgery Score is easily calculated using multiple demographic, comorbidity, laboratory, and acuity of disease variables. We aimed to investigate whether the Emergency Surgery Score can predict 30-day postoperative mortality across patients undergoing emergency surgery in multiple surgical specialties. METHODS: Our study is a retrospective cohort study using data from the national American College of Surgeons National Surgical Quality Improvement Program database (2007-2017). We included patients that underwent emergency gynecologic, urologic, thoracic, neurosurgical, orthopedic, vascular, cardiac, and general surgical procedures. The Emergency Surgery Score was calculated for each patient, and the correlation between the Emergency Surgery Score and 30-day mortality was assessed for each specialty using the c-statistics methodology. RESULTS: Of 6,485,915 patients, 173,890 patients were included. The mean age was 60 years, 50.6% were female patients, and the overall mortality was 9.7%. The Emergency Surgery Score predicted mortality best in emergency gynecologic, general, and urologic surgery (c-statistics: 0.97, 0.87, 0.81, respectively). The Emergency Surgery Score predicted mortality moderately well in emergency thoracic, neurosurgical, orthopedic, and vascular surgery (c-statistics 0.73-0.79). For example, the mortality of gynecology patients with an Emergency Surgery Score of 5, 9, and 13 was 2%, 27%, and 50%, respectively. The Emergency Surgery Score performed poorly in cardiac surgery. CONCLUSION: The Emergency Surgery Score accurately predicts mortality across patients undergoing emergency surgery in multiple surgical specialties, especially general, gynecologic, and urologic surgery. The Emergency Surgery Score can prove useful for perioperative patient counseling and for benchmarking the quality of surgical care.

Abdominal Wall Thickness Predicts Surgical Site Infection in Emergency Colon Operations.

BACKGROUND: Body mass index (BMI) does not reliably predict Surgical site infections (SSI). We hypothesize that abdominal wall thickness (AWT) would serve as a better predictor of SSI for patients undergoing emergency colon operations. METHODS: We retrospectively evaluated our Emergency Surgery Database (2007-2018). Emergency colon operations for any indication were included. AWT was measured by pre-operative CT scans at 5 locations. Only superficial and deep SSIs were considered as SSI in the analysis. Univariate then multivariable analyses were used to determine predictors of SSI. RESULTS: 236 patients met inclusion criteria. The incidence of post-operative SSI was 25.8% and the median BMI was 25.8kg/m2 [22.5-30.1]. The median AWT between patients with and without SSI was significantly different (2.1cm [1.4, 2.8] and 1.8cm [1.2, 2.5], respectively). A higher BMI trended toward increased rates of SSI, but this was not statistically significant. In overweight (BMI 25-29.9kg/m2) and obese (BMI ≥30kg/m2) patients, SSI versus no SSI rates were (50.0% versus 41.9% and 47.4% versus 36.4%, P = 0.365 and 0.230) respectively. The incidence of SSI in patients with an average AWT < 1.8cm was 20% and 30% for patients with average AWT ≥1.8cm. On multivariable analysis, AWT ≥1.8cm at 2cm inferior to umbilicus was an independent predictor of SSI (OR 2.98, 95%CI 1.34-6.63, P = 0.007). CONCLUSIONS: AWT is a better predictor of SSI than BMI. Preoperative imaging of AWT may direct intraoperative decisions regarding wound management. Future clinical outcomes research in emergency surgery should include abdominal wall thickness as an important patient variable.

Development of a field artificial intelligence triage tool: Confidence in the prediction of shock, transfusion, and definitive surgical therapy in patients with truncal gunshot wounds.

BACKGROUND: In-field triage tools for trauma patients are limited by availability of information, linear risk classification, and a lack of confidence reporting. We therefore set out to develop and test a machine learning algorithm that can overcome these limitations by accurately and confidently making predictions to support in-field triage in the first hours after traumatic injury. METHODS: Using an American College of Surgeons Trauma Quality Improvement Program-derived database of truncal and junctional gunshot wound (GSW) patients (aged 16-60 years), we trained an information-aware Dirichlet deep neural network (field artificial intelligence triage). Using supervised training, field artificial intelligence triage was trained to predict shock and the need for major hemorrhage control procedures or early massive transfusion (MT) using GSW anatomical locations, vital signs, and patient information available in the field. In parallel, a confidence model was developed to predict the true-class probability (scale of 0-1), indicating the likelihood that the prediction made was correct, based on the values and interconnectivity of input variables. RESULTS: A total of 29,816 patients met all the inclusion criteria. Shock, major surgery, and early MT were identified in 13.0%, 22.4%, and 6.3% of the included patients, respectively. Field artificial intelligence triage achieved mean areas under the receiver operating characteristic curve of 0.89, 0.86, and 0.82 for prediction of shock, early MT, and major surgery, respectively, for 80/20 train-test splits over 1,000 epochs. Mean predicted true-class probability for errors/correct predictions was 0.25/0.87 for shock, 0.30/0.81 for MT, and 0.24/0.69 for major surgery. CONCLUSION: Field artificial intelligence triage accurately identifies potential shock in truncal GSW patients and predicts their need for MT and major surgery, with a high degree of certainty. The presented model is an important proof of concept. Future iterations will use an expansion of databases to refine and validate the model, further adding to its potential to improve triage in the field, both in civilian and military settings. LEVEL OF EVIDENCE: Prognostic, Level III.

Modified Frailty Index-5 Score and Post-Operative Infectious Complications in Patients Undergoing Surgery for Intestinal-Cutaneous Fistula: A Nationwide Retrospective Cohort Analysis.

Background: Post-operative infectious complications after repair of intestinal-cutaneous fistulas (ICF) represent a substantial burden and these outcomes vary widely in the literature. We aimed to evaluate the use of the modified frailty index-5 (mFI-5) to account for physiologic reserve to predict infectious complications in patients with ICF undergoing operative repair. Methods: We used the American College of Surgeon National Surgical Quality Improvement Program (ACS-NSQIP) 2006-2017 dataset to include patients who underwent ICF repair. The main outcome measure was 30-day infectious complications (surgical site infection [SSI], sepsis, pneumonia, and urinary tract infection [UTI]). The risk of 30-day post-operative infectious complications was assessed based on mFI-5 score. We performed multivariable logistic regression analyses to evaluate the association between infectious complications and mFI-5. Results: We identified 4,197 patients who underwent an ICF repair. The median age (interquartile range [IQR]) was 57 (46, 67) years, and the majority of patients were female (2,260; 53.9%); white (3,348; 79.8%); and 1,586 (38.3%) were obese. After adjustment for relevant confounders such as baseline patient characteristics, and operative details, mFI-5 was independently associated with infectious complications (odds ratio [OR], 2.00; 95% confidence interval [CI], 1.25-3.21), particularly SSI (OR, 2.16; 95% CI, 1.28-3.63) and pneumonia (OR, 5.31; 95% CI, 2.29-12.35), but not UTI or sepsis. Conclusions: We showed that the mFI-5 is a strong predictor of infectious complications after ICF repair. It can be utilized to account for physiologic reserve, therefore reducing the variability of outcomes reported for ICF repair.

Implications of the national Stop the Bleed campaign: The swinging pendulum of prehospital tourniquet application in civilian limb trauma.

BACKGROUND: Prehospital tourniquet (PHT) utilization has increased in response to mass casualty events. We aimed to describe the incidence, therapeutic effectiveness, and morbidity associated with tourniquet placement in all patients treated with PHT application. METHODS: A retrospective observational cohort study was performed to evaluate all adults with a PHT who presented at two Level I trauma centers between January 2015 and December 2019. Medically trained abstractors determined if the PHT was clinically indicated (placed for limb amputation, vascular hard signs, injury requiring hemostasis procedure, or significant documented blood loss). Prehospital tourniquets were further designated as appropriately or inappropriately applied (based on PHT anatomic placement location, occurrence of a venous tourniquet, or ischemic time defined as >2 hours). Statistical analyses were performed to generate primary and secondary results. RESULTS: A total of 147 patients met study inclusion criteria, of which 70% met the criteria for trauma registry inclusion. Total incidence of PHT utilization increased from 2015 to 2019, with increasing proportions of PHTs placed by nonemergency medical service personnel. Improvised PHTs were frequently used. Prehospital tourniquets were clinically indicated in 51% of patients. Overall, 39 (27%) patients had a PHT that was inappropriately placed, five of which resulted in significant morbidity. CONCLUSION: In summary, prehospital tourniquet application has become widely adopted in the civilian setting, frequently performed by civilian and nonemergency medical service personnel. Of PHTs placed, nearly half had no clear indication for placement and over a quarter of PHTs were misapplied with notable associated morbidity. Results suggest that the topics of clinical indication and appropriate application of tourniquets may be important areas for continued focus in future tourniquet educational programs, as well as future quality assessment efforts. LEVEL OF EVIDENCE: Epidemiological, level III; Therapeutic, level IV.

Multisystem outcomes and predictors of mortality in critically ill patients with COVID-19: Demographics and disease acuity matter more than comorbidities or treatment modalities.

BACKGROUND: We sought to describe characteristics, multisystem outcomes, and predictors of mortality of the critically ill COVID-19 patients in the largest hospital in Massachusetts. METHODS: This is a prospective cohort study. All patients admitted to the intensive care unit (ICU) with reverse-transcriptase-polymerase chain reaction-confirmed severe acute respiratory syndrome coronavirus 2 infection between March 14, 2020, and April 28, 2020, were included; hospital and multisystem outcomes were evaluated. Data were collected from electronic records. Acute respiratory distress syndrome (ARDS) was defined as PaO2/FiO2 ratio of ≤300 during admission and bilateral radiographic pulmonary opacities. Multivariable logistic regression analyses adjusting for available confounders were performed to identify predictors of mortality. RESULTS: A total of 235 patients were included. The median (interquartile range [IQR]) Sequential Organ Failure Assessment score was 5 (3-8), and the median (IQR) PaO2/FiO2 was 208 (146-300) with 86.4% of patients meeting criteria for ARDS. The median (IQR) follow-up was 92 (86-99) days, and the median ICU length of stay was 16 (8-25) days; 62.1% of patients were proned, 49.8% required neuromuscular blockade, and 3.4% required extracorporeal membrane oxygenation. The most common complications were shock (88.9%), acute kidney injury (AKI) (69.8%), secondary bacterial pneumonia (70.6%), and pressure ulcers (51.1%). As of July 8, 2020, 175 patients (74.5%) were discharged alive (61.7% to skilled nursing or rehabilitation facility), 58 (24.7%) died in the hospital, and only 2 patients were still hospitalized, but out of the ICU. Age (odds ratio [OR], 1.08; 95% confidence interval [CI], 1.04-1.12), higher median Sequential Organ Failure Assessment score at ICU admission (OR, 1.24; 95% CI, 1.06-1.43), elevated creatine kinase of ≥1,000 U/L at hospital admission (OR, 6.64; 95% CI, 1.51-29.17), and severe ARDS (OR, 5.24; 95% CI, 1.18-23.29) independently predicted hospital mortality.Comorbidities, steroids, and hydroxychloroquine treatment did not predict mortality. CONCLUSION: We present here the outcomes of critically ill patients with COVID-19. Age, acuity of disease, and severe ARDS predicted mortality rather than comorbidities. LEVEL OF EVIDENCE: Prognostic, level III.

The Current Role of Interventional Radiology in the Management of Acute Trauma Patient.

Trauma is one of the most common causes of death, particularly in younger individuals. The development of specialized trauma centers, trauma-specific intensive care units, and trauma-focused medical subspecialties has led to the formation of comprehensive multidisciplinary teams and an ever-growing body of research and innovation. The field of interventional radiology provides a unique set of minimally invasive, endovascular techniques that has largely changed the way that many trauma patients are managed. This article discusses the role of interventional radiology in the care of this complex patient population, and in particular how the specialty fits into the overall team management of these patients.

Deep immune profiling of whole blood to identify early immune signatures that correlate to patient outcome after major trauma.

BACKGROUND: Major injury results in an early cascade of immunologic responses that increase susceptibility to infection and multiorgan dysfunction. Detailed immune profiling by mass cytometry has the potential to identify immune signatures that correspond to patient outcomes. Our objective was to determine the prognostic value of immune signatures early after major trauma injury. METHODS: Trauma patients (n = 17) were prospectively enrolled between September 2018 and December 2019. Serial whole blood samples were obtained from trauma patients (mean Injury Severity Score, 26.2; standard error of the mean, 3.7) at Days 1 and 3 after injury, and from age- and sex-matched uninjured controls using a standardized protocol for fixation, storage, and labeling. Computational analyses including K-nearest neighbor automated clustering of immune cells and Spearman's correlation analysis were used to identify correlations between cell populations, clinical measures, and patient outcomes. RESULTS: Analysis revealed nine immune cell clusters that correlated with one or more clinical outcomes. On Days 1 and 3 postinjury, the abundance of immature neutrophil and classical monocytes exhibited a strong positive correlation with increased intensive care unit and hospital length of stay. Conversely, the abundance of CD4 T-cell subsets, namely Th17 cells, is associated with improved patient outcomes including decreased ventilator days (r = -0.76), hospital-acquired pneumonia (r = -0.69), and acute kidney injury (r = -0.73). CONCLUSION: Here, we provide a comprehensive multitime point immunophenotyping analysis of whole blood from patients soon after traumatic injury to determine immune correlates of adverse outcomes. Our findings indicate that alterations in myeloid-origin cell types may contribute to immune dysfunction after injury. Conversely, the presence of effector T cell populations corresponds with decreased hospital length of stay and organ dysfunction. Overall, these data identify novel immune signatures following traumatic injury that support the view that monitoring of immune (sub)-populations may provide clinical decision-making support for at-risk patients early in their hospital course. LEVEL OF EVIDENCE: Prognostic/Epidemiologic, Level IV.