Patient-controlled epidural analgesia, patient-controlled intravenous analgesia, and conventional intravenous opioids for gynecologic interstitial brachytherapy: A single-center retrospective study.

PURPOSE Interstitial brachytherapy for gynecologic malignancies is stressful physically and mentally; however, optimal analgesic methods remain unclear. We investigated the effect of analgesic methods on pain and adverse events during interstitial brachytherapy for gynecologic malignancies. METHODS The data of 73 patients who underwent interstitial brachytherapy for gynecologic malignancies between April 2015 and March 2020 were retrospectively analyzed. Patient-controlled epidural analgesia (PCEA), patient-controlled intravenous analgesia (PCIA), and conventional intravenous opioid administration were used for analgesia during treatment. We compared the analgesic effects based on a numerical rating scale (NRS), the number of additional analgesics, and the adverse events associated with analgesia. The NRS score was calculated as an average value for every 12 h (NRS1: treatment on the 1st day from 12 to 24 o'clock; NRS2: treatment on the 2nd day from 0 to 12 o'clock; NRS3: treatment on the 2nd day from 12 to 24 o'clock). The mean NRS score differences between the methods were evaluated using mixed models for repeated-measures analyses. RESULTS The NRS score was significantly lower at all times for PCEA (NRS1: p = 0.003; NRS2: p = 0.011; NRS3: p < 0.001). NRS2 and NRS3 were significantly lower for PCIA (NRS2: p = 0.043; NRS3: p < 0.001) than for the conventional method. The NRS scores for PCEA and PCIA were not significantly different. Moreover, additional analgesics and adverse events did not differ between the three treatments. CONCLUSION PCEA and PCIA were superior to conventional intravenous opioids for analgesia in interstitial brachytherapy for gynecologic malignancies. However, adverse events associated with PCEA and PCIA were not reduced.