Min et al. [1] investigated the effects of palonosetron, a second-generation 5-hydroxytryptamine-3 receptor antagonist, on corrected QT (QTc) intervals on electrocardiograms of patients undergoing laparotomies under sevoflurane anesthesia. Considering that prolongation of the QTc interval is associated with torsades de pointes, and palonosetron may at least theoretically increase QTc intervals by similar pharmacological mechanisms as ondansetron [2], clinicians will agree that an investigation into the effects of palonosetron on QTc intervals is required. Careful consideration is, however, needed, although Min et al. [1] concluded that palonosetron may induce QTc prolongation during general anesthesia with sevoflurane.

We understand In's opinion. We performed the study to assess the effects of palonosetron on prolongation of the corrected QT intervals (QTc). We concluded that palonosetron might induce the prolongation of QTc. In our retrospective controlled study, we did not exclude patients who took other medicines, such as famotidine, which is known to affect the prolongation of QTc, because we measured the baseline QTc from the surgical record after monitoring during surgery in the operating theater. Although there was a significant difference between the two groups in terms of famotidine in our results, baseline QTc did not differ between the two groups. Moreover, the numbers of patients who were administered preoperative famotidine were higher in the control group than the QT prolongation group, even though famotidine can cause QT prolongation. Also, in fact, cases of QT prolongation induced due by famotidine are reported only rarely [1]. Our analysis could be subject to hidden biases, as we noted in the limitations section, since it was a retrospective study. We also hope that further well-designed studies on this subject will be performed.