Impact of Focused Intraoperative Transthoracic Echocardiography by Anaesthesiologists on Management in Hemodynamically Unstable High-Risk Noncardiac Surgery Patients

Abstract

Perioperative hemodynamic monitoring and intervention using transthoracic echocardiography (TTE) in highrisk surgery patients can decrease the rates of adverse events, morbidity, and mortality; however, evidence regarding its benefits is required. This prospective interventional study aimed at evaluating the efficacy of intraoperative TTE to alter patient management in high-risk and extensively monitored surgical patients susceptible to hemodynamic instability. The study included 52 hemodynamically unstable high-risk abdominal, vascular, or thoracic surgery patients. Patients were anesthetized, and focused TTE was performed when intraoperative hemodynamic instability occurred (hypotension or low cardiac output for a period of ≥3 minutes). Cardiac output monitoring system using pulse contour analysis was established before induction of anesthesia. The definitive therapy leading to an alteration of management was guided by the results of the focused TTE. Differences between intended and actual therapies and changes in management were documented as the primary end points. The analysis of TTE quality and description of pathophysiologic cardiovascular findings were the secondary end points. Sample size estimation and statistical analyses were performed with the statistical software R (www.r-project.org). Changes of management were noted in 33 patients (66%; 95% confidence interval, 52.11%–77.61%) and 38 hemodynamic situations (46.34%; 95% confidence interval, 35.95%–57.06%) of the 50 hemodynamically unstable patients examined by additional focused TTE. Transthoracic echocardiography identified pathologic findings in 47 patients: hypovolemia (66%), left ventricular dysfunction (8%), right ventricular overload (22%), and right-sided heart failure (4%). Lack of randomization and the absence of a control group were the major limitations of this study.