Effect of Titrated Dexmedetomidine versus Esmolol on Postoperative Myocardial Injury in High-Risk Patients Undergoing...

Laparoscopic pneumoperitoneum induces tachycardia and hemodynamic instability, key drivers of myocardial injury after noncardiac surgery (MINS). This randomized controlled trial evaluated whether a proactive hemodynamic management protocol based on titrated dexmedetomidine or esmolol could reduce the incidence of MINS in high-risk patients undergoing laparoscopic colorectal cancer surgery compared with conventional management.

A total of 270 high-risk patients undergoing elective laparoscopic colorectal cancer surgery were randomly assigned to conventional management (Group C), dexmedetomidine infusion (Group D), or esmolol infusion (Group E). Infusions in the two active groups were titrated to maintain an intraoperative heart rate between 50 and 70 beats/min. The primary outcome was the incidence of MINS within 48 hours postoperatively.

In the primary ITT analysis, the incidence of MINS was lower in Group D (7.8%, 7/90) than in Group C (20.0%, 18/90), although this difference did not reach the Bonferroni-adjusted significance threshold (P = 0.018; adjusted α = 0.0167). The reduction in Group E compared with Group C (11.1% vs 20.0%) was not statistically significant (P = 0.121). In the prespecified PP sensitivity analysis, Group D had a significantly lower MINS incidence than Group C (6.9% vs 20.7%, P = 0.008). Patients receiving dexmedetomidine exhibited more stable intraoperative hemodynamics and lower postoperative lactate levels, without an increased incidence of hypotension.

In high-risk patients undergoing laparoscopic colorectal cancer surgery, titrated dexmedetomidine showed a potential trend toward reduced MINS incidence compared with conventional management, with a more pronounced signal in the PP analysis. This cardioprotective signal may be associated with improved intraoperative hemodynamic stability, although the evidence is exploratory.