Risk Factors and Prevalence of QTc Prolongation in Adult Burn Patients Receiving Methadone

Methadone is an opioid commonly used for acute pain management in burn patients. One adverse effect of methadone is QTc interval prolongation, which may be associated with adverse cardiac outcomes. There is currently a paucity of data regarding risk of QTc prolongation in burn patients taking methadone and a lack of evidence-based recommendations for monitoring strategies in this population. The study objective was to determine the prevalence, risk factors, and cardiac outcomes related to methadone-associated QTc prolongation in adult burn patients. A total of 91 patients were included and were divided into groups according to maximum QTc. QTc prolongation was defined as greater than or equal to 470 ms (males) or 480 ms (females). There were no differences between groups regarding patient-specific risk factors, baseline QTc, or time to longest QTc. Patients in the prolonged QTc group had a higher rate of cardiac events (44% vs 9%; P <.001), higher median (IQR) change from baseline to longest QTc (61 ms [18,88] vs 23 ms [13,38]; P <.001), higher median (IQR) total daily dose of methadone (90 mg [53,98] vs 53 mg [30,75]; P =.004), and longer median (IQR) length of stay (53 [33,82] vs 35 [26,52] days; P =.008). QTc prolongation in burn patients was associated with increased methadone dose and resulted in a higher rate of cardiac events. This study was the first of its kind to look at risk factors and cardiac outcomes associated with methadone use in burn patients.