Association between intraoperative methadone administration and QTc interval prolongation: a propensity score-matched...

Area of Science:

• Anesthesiology and Perioperative Medicine
• Cardiology
• Pharmacology

Background:

• Perioperative methadone use is rising for pain management.
• Methadone is known to prolong the QTc interval, increasing Torsades de Pointes risk.
• The impact of intraoperative methadone loading doses on QTc prolongation is not well-understood.

Purpose of the Study:

• To investigate the association between intraoperative methadone loading doses and QTc interval prolongation.
• To evaluate the incidence of QTc prolongation exceeding specific thresholds in patients receiving methadone during surgery.

Main Methods:

• Retrospective observational cohort study of adult patients undergoing major non-cardiopulmonary surgery.
• Comparison of patients receiving intraoperative methadone loading dose versus those who did not.
• Analysis of electrocardiograms (ECGs) using a wavelet-based algorithm to measure QTc intervals at baseline and intraoperatively.
• Propensity score matching to control for confounding variables.

Main Results:

• After propensity score matching, no significant differences in QTc interval prolongation were observed between the methadone and non-methadone groups.
• Incidence of QTc interval >500 ms, increase of ≥30 ms, and increase of ≥60 ms from baseline were similar between groups.
• The non-methadone group spent a significantly higher percentage of intraoperative time above the >500 ms threshold.

Conclusions:

• Intraoperative methadone loading doses were not associated with an increased incidence of intraoperative QTc interval prolongation.
• Methadone can be safely implemented for perioperative pain management without significantly increasing QTc prolongation risks.
• Further research may explore long-term cardiac effects and optimal dosing strategies.