(Purpose) To determine the efficacy of scheduled intravenous or oral acetaminophen administration after robotic-assisted laparoscopic radical prostatectomy (RARP) in our hospital. (Subjects and methods) We retrospectively analyzed 173 patients who underwent RARP at our hospital between April 2019 and December 2020. The patients were divided into three groups (A, B, and C) according to the use of postoperative analgesia. Group A patients were administered acetaminophen only when needed. Group B patients were administered intravenous acetaminophen every 6 h from the day of surgery to postoperative day 2. Group C patients were prescribed oral acetaminophen from 3 to 7 days postoperatively in addition to being administered intravenous acetaminophen (similar to group B). Multivariate analysis was performed to determine whether scheduled intravenous or oral acetaminophen administration reduced unscheduled analgesic use. (Results) There were 110, 33, and 30 patients in groups A, B, and C, respectively. Significant differences in lymph node dissection rates were observed between groups A and B (70.9% vs 36.4%; P=0.001) and groups A and C (70.9% vs 33.3%; P< 0.001); furthermore, significant differences in the frequency of preoperative androgen blockade therapy were observed between groups A and C (20% vs 3.3%; P=0.029). Logistic regression analysis showed that only scheduled intravenous and oral administration of acetaminophen on postoperative days 0 to 2 was an independent factor for postoperative pain (group A vs group B: OR=0.127; 0.046-0.355; P< 0.001 and group A vs group C: OR=0.133; 0.046-0.390; P< 0.001). On postoperative days 3 to 7, there was no significant difference in the unscheduled use of analgesics between groups A and B. Only 1 of the 30 group C patients received unscheduled analgesia. (Conclusions) Scheduled intravenous or oral administration of acetaminophen may reduce unscheduled analgesic use after RARP.
Keywords: acetaminophen; postoperative analgesia; robotic-assisted laparoscopic radical prostatectomy.