Intraoperative hypotension and perioperative acute ischemic stroke in patients having major elective non-cardiovascular non-neurological surgery.

PURPOSE: The association between intraoperative hypotension and perioperative acute ischemic stroke is not well described. We hypothesized that intraoperative hypotension would be associated with perioperative acute ischemic stroke. METHODS: Four-year retrospective cohort study of elective non-cardiovascular, non-neurological surgical patients. Characteristics of patients who had perioperative acute ischemic stroke were compared against those of patients who did not have acute ischemic stroke. Multivariable logistic regression was used to determine whether hypotension was independently associated with increased odds of perioperative acute ischemic stroke. RESULTS: Thirty-four of 9816 patients (0.3%) who met study inclusion criteria had perioperative acute ischemic stroke. Stroke patients were older and had more comorbidities including hypertension, coronary artery disease, diabetes mellitus, active tobacco use, chronic obstructive pulmonary disease, cerebral vascular disease, atrial fibrillation, and peripheral vascular disease (all P < 0.05). MAP < 65 mmHg was not associated with increased odds of acute ischemic stroke when modeled as a continuous or categorical variable. MAP < 60 mmHg for more than 20 min was independently associated with increased odds of acute ischemic stroke, OR = 2.67 [95% CI = 1.21 to 5.88, P = 0.02]. CONCLUSION: Our analysis suggests that when MAP is less than 60 mmHg for more than 20 min, there is increased odds of acute ischemic stroke. Further studies are needed to determine what MAP should be targeted during surgery to optimize cerebral perfusion and limit ischemic stroke risk.

The Algorithm Examining the Risk of Massive Transfusion (ALERT) Score Accurately Predicts Massive Transfusion at the Scene of Injury and on Arrival to the Trauma Bay: A Retrospective Analysis.

BACKGROUND: Massive transfusion (MT) is required to resuscitate traumatically injured patients with complex derangements. Scoring systems for MT typically require laboratory values and radiological imaging that may delay the prediction of MT. STUDY DESIGN: The Trauma ALgorithm Examining the Risk of massive Transfusion (Trauma ALERT) study was an observational cohort study. Prehospital and admission ALERT scores were constructed with logistic regression of prehospital and admission vitals, and FAST examination results. Internal validation was performed with bootstrap analysis and cross-validation. RESULTS: The development cohort included 2,592 patients. Seven variables were included in the prehospital ALERT score: systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), respiratory rate (RR), SpO2, motor Glasgow Coma Scale (GCS) score, and penetrating mechanism. Eight variables from 2,307 patients were included in the admission ALERT score: admission SBP, HR, RR, GCS score, temperature, FAST examination result, and prehospital SBP and DBP.The area under the receiving operator characteristic curve for the prehospital and admission models were 0.754 (95% bootstrapped CI 0.735-0.794, P < 0.001) and 0.905 (95% bootstrapped CI 0.867-0.923, P < 0.001), respectively. The prehospital ALERT score had equivalent diagnostic accuracy to the ABC score (P = 0.97), and the admission ALERT score outperformed both the ABC and the prehospital ALERT scores (P < 0.0001). CONCLUSION: The prehospital and admission ALERT scores can accurately predict massive transfusion in trauma patients without the use of time-consuming laboratory studies, although prospective studies need to be performed to validate these findings. Early identification of patients who will require MT may allow for timely mobilization of scarce resources and could benefit patients by making blood products available for treating hemorrhagic shock.