Hyperlactemia Predicts Surgical Mortality in Patients Presenting With Acute Stanford Type-A Aortic Dissection

Objective: Inspired by the limited facility of the Penn classification, the authors aimed to determine a rapid and optimal preoperative assessment tool to predict surgical mortality after acute Stanford type-A aortic dissection (AAAD) repair. Design: Patients who underwent an attempted surgical repair of AAAD were determined using a de-identified single institution database. The charts of 144 patients were reviewed retrospectively for preoperative demographics and surrogates for disease severity and malperfusion. Bivariate analysis was used to determine significant (p <= 0.05) predictors of in-hospital and 1-year mortality, the primary endpoints. Receiver operating characteristic curve generation was used to define optimal cut-off values for continuous predictors. Setting: Single center, level I trauma, university teaching hospital. Participants: The study included 144 cardiac surgical patients with acute type-A aortic dissection presenting for surgical correction. Interventions: Surgical repair of aortic dissection with preoperative laboratory samples drawn before patient transfer to the operating room or immediately after arterial catheter placement intraoperatively. Measurements and Main Results: The study cohort comprised 144 patients. In-hospital mortality was 9%, and the I-year mortality rate was 17%. Variables that demonstrated a correlation with in-hospital mortality included an elevated serum lactic acid level (odds ratio [OR] 1.5 [1.31.9], p < 0.001), a depressed ejection fraction (OR 0.91 [0.86-0.96], p =.001), effusion (OR 4.8 [1.02-22.5], p = 0.04), neurologic change (OR 5.3 [1.6-17.4], p = 0.006), severe aortic regurgitation (OR 8.2 [2.0-33.9], p = 0.006), and cardiopulmonary resuscitation (OR 6.8 [1.7-26.9], p = 0.01). Only an increased serum lactic acid level demonstrated a trend with 1-year mortality using univariate Cox regression (hazard ratio 1.1 [1.0-1.1], p = 0.006). Receiver operating characteristic analysis revealed optimal cut-off lactic acid levels of 6.0 mmoUL and 6.9 mmol/L for in-hospital and 1-year mortality, respectively. Conclusion: Lactic acidosis, ostensibly as a surrogate for systemic malperfusion, represents a novel, accurate, and easily obtainable preoperative predictor of short-term mortality after attempted AAAD repair. These data may improve identification of patients who would not benefit from surgery. (C)2017 Elsevier Inc. All rights reserved.