False sense of safety by daily QTc interval monitoring during methadone IVPCA titration in a patient with chronic pain
Hector Miranda-Grajales, Joy Hao, Ricardo A Cruciani
Department of Pain Medicine and Palliative Care, Beth Israel Medical Center, New York, NY, USA
Abstract: It has been proposed that some deaths attributed to methadone are related to prolongation of the QTc interval; however, there are no clear recommendations on electrocardiogram (ECG) monitoring in patients undergoing intravenous methadone infusion. This is a report on a patient receiving methadone intravenous patient-controlled analgesia titration for the treatment of chronic pain. Initially, her daily ECGs showed QTc intervals within normal limits; however, she experienced a rapid increase in QTc interval from 317 ms to 784 ms within a 24-hour period after methadone had been discontinued for excessive sedation. QTc interval greater than 500 ms is considered to be high risk for the fatal arrhythmia Torsades de Pointes. Daily ECGs did not detect a gradual increase in the QTc interval that would have alerted the medical staff of the need to decrease or stop the methadone before reaching a prolonged QTc interval associated with cardiotoxicity. In selected cases where aggressive methadone titration is required, more intensive monitoring, such as telemetry or ECG determinations every 12 hours, might help detect changes in QTc interval duration that might otherwise be missed by daily ECG determinations.
Keywords: methadone, QTc prolongation, opioids, opioid side effects, IVPCA methadone
This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.Download Article [PDF] View Full Text [HTML][Machine readable]