Does ramosetron reduce postoperative emesis and pain after TKA?

Current pain management protocols involving many anesthetic and analgesic drugs reportedly provide adequate analgesia after TKA. However, control of emetic events associated with the drugs used in current multimodal pain management remains challenging.

We determined (1) whether ramosetron prophylaxis reduces postoperative emetic events; and (2) whether it influences pain levels and opioid consumption in patients managed with a current multimodal pain management protocol after TKA.

We randomized 119 patients undergoing TKA to receive either ramosetron (experimental group, n = 60) or no prophylaxis (control group, n = 59). All patients received regional anesthesia, preemptive analgesic medication, continuous femoral nerve block, periarticular injection, and fentanyl-based intravenous patient-controlled analgesia. We recorded the incidence of emetic events, rescue antiemetic requirements, complete response, pain level, and opioid consumption during three periods (0-6, 6-24, and 24-48 hours postoperatively). The severity of nausea was evaluated using a 0 to 10 VAS.

The ramosetron group tended to have a lower incidence of nausea with a higher complete response and tended to have less severe nausea and fewer rescue antiemetic requirements during the 6- to 24-hour period. However, the overall incidences of emetic events, rescue antiemetic requirements, and complete response were similar in both groups. We found no differences in pain level or opioid consumption between the two groups.

Ramosetron reduced postoperative emetic events only during the 6- to 24-hour postoperative period and did not affect pain relief. More efficient measures to reduce emetic events after TKA should be explored.

Level I, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.