Validation of the American Association for the Surgery of Trauma grading system for acute mesenteric ischemia-More than anatomic severity is needed to determine risk of mortality.

BACKGROUND: Acute mesenteric ischemia (AMI) is a highly morbid disease with a diverse etiology. The American Association for the Surgery of Trauma (AAST) proposed disease-specific grading scales intended to quantify severity based upon clinical, imaging, operative, and pathology findings. This grading scale has not been yet been validated for AMI. The goal of this study was to evaluate the correlation between the grading scale and complication severity. METHODS: Patients for this single center retrospective chart review were identified using diagnosis codes for AMI (ICD10-K55.0, ICD9-557.0). Inpatients >17 years old from the years 2008 to 2015 were included. The AAST grades (1-5) were assigned after review of clinical, imaging (computed tomography), operative and pathology findings. Two raters applied the scales independently after dialog with consensus on a learning set of cases. Mortality and Clavien-Dindo complication severity were recorded. RESULTS: A total of 221 patients were analyzed. Overall grade was only weakly correlated with Clavien-Dindo complication severity (rho = 0.27) and mortality (rho = 0.21). Computed tomography, pathology, and clinical grades did not correlate with mortality or outcome severity. There was poor interrater agreement between overall grade. A mortality prediction model of operative grade, use of vasopressors, preoperative serum creatinine and lactate levels showed excellent discrimination (c-index = 0.93). CONCLUSION: In contrast to early application of other AAST disease severity scales, the AMI grading scale as published is not well correlated with outcome severity. The AAST operative grade, in conjunction with vasopressor use, creatinine, and lactate were strong predictors of mortality. LEVEL OF EVIDENCE: Prognostic study, III.

Outcomes of Patients Who Undergo Cardiac Surgical Procedures After Liver Transplantation.

BACKGROUND: There is a paucity of information available regarding the impact of cardiac surgical procedures on patients who have undergone previous liver transplantation. The primary purpose of this study was to ascertain the survival rate and predictors of death in this specific patient population. METHODS: This retrospective cohort study consisted of a consecutive series of patients with a functioning liver allograft who subsequently underwent cardiac surgical procedures between January 1991 and December 2012. The optimal Model for End-Stage Liver Disease (MELD) score for predicting late death was identified using receiver operating characteristic curve analysis. Risk of postoperative death was determined by parametric hazard analysis. RESULTS: Between January 1991 and December 2012, 43 patients (median age, 60 years) underwent cardiac surgical procedures after liver transplantation. The median interval between liver transplant and cardiac operation was 63 months (range, 1.1 to 217 months). Three operative deaths and 24 late deaths occurred. Receiver operating characteristic curve analysis identified the optimal preoperative and postoperative MELD score cut points for predicting late death as greater than 13.8 (area under the curve = 0.674) and greater than 17 (area under the curve = 0.633), respectively. Patients with a preoperative MELD score of 13.8 or less had significantly greater survival rates than those with a MELD score greater than 13.8 (p = 0.028); patients with a postoperative MELD score of 17 of less had significantly greater survival rates than those with a MELD score greater than 17 (p < 0.001). Multivariate parametric hazard analysis identified postoperative peak creatinine level as a statistically significant predictor of death (relative risk, 1.8; p = 0.01). The 1-, 5-, and 10-year Kaplan-Meier survival rates were 90%, 51%, and 35%, respectively; postoperative mortality rates followed a constant phase model with a hazard of death of 10% per year. CONCLUSIONS: Cardiac surgical procedures can be performed with acceptable short-term and long-term outcomes in liver transplant recipients. Elevated preoperative and postoperative MELD scores and postoperative peak creatinine level may portend death in this cohort. There is a constant hazard of death of 10% per year.