Effects of preoperative, scheduled administration of antiemetics on reducing postoperative nausea and vomiting in patients undergoing total knee arthroplasty

Background To date, there has been no established protocol regarding the timing of the scheduled administration of antiemetics in total knee arthroplasty (TKA). Previous prospective studies analyzing the scheduled use of antiemetics differed in the timing at which the drugs were administered. However, antiemetic drugs are not administered post-operatively until noxious stimuli caused by drugs used during anesthesia and operative procedures. The purpose of this study was 1) to determine whether preoperative scheduled administration of an antiemetic drug can reduce iatrogenic postoperative nausea and vomiting (PONV) in TKA compared to postoperative administration, and 2) to determine whether there was a difference in postoperative pain, patient satisfaction, and complications after TKA between pre- and postoperative administrations.Methods This retrospective study included patients who were assigned to either intravenous administration of the antiemetic drug (ramosetron) 1 hour before surgery (pre-injection group: 50 patients) or at the end of surgery (post-injection group: 51 patients). The incidence of PONV and the frequency of rescue medicine use were recorded until 48 hours postoperation. Postoperative pain level and satisfaction were also assessed using the visual analogue scale (VAS). Possible complications associated with serotonin receptor antagonists; for example, headaches, dizziness, and drowsiness were also assessed.Results The incidence of nausea events was lower in the pre-injection group than in the post-injection group. However, there was no difference between the two groups in terms of frequency of vomiting events and the use of rescue medicine for PONV. Also, postoperative pain, satisfaction scores, and incidence of complications were not different between the two groups.Conclusions The patients with preoperative scheduled administration of antiemetics showed lower incidence of nausea events than those with postoperative administration. However, it is difficult to conclude that the extent of the effect was clinically significant. Further research is needed to determine the optimal timing and method for more effective antiemetic treatment.