The Effect of Timing of Ondansetron Administration on Nausea and Vomiting during Intravenous Patient-Controlled Analgesia / 대한마취과학회지

BACKGROUND: This study was designed to establish the optimal timing of administration of ondansetron for prevention of postoperative nausea and vomiting (PONV) during intravenous patient-controlled analgesia (IV-PCA). METHODS: Eighty women undergoing a total abdominal hysterectomy under general anesthesia were randomized to receive a placebo (n = 20, group 1), ondansetron 2 mg before induction and 2 mg after surgery (n = 20, group 2), ondansetron 4 mg before induction (n = 20, group 3), or ondansetron 4 mg after surgery (n = 20, group 4). An IV-PCA using butorphanol and ketorolac was connected to the patients after waking from the anesthesia. The incidences and severity of nausea and vomiting were recorded for 48 hr postop. RESULTS: The incidences of nausea and vomiting in group 1 (75%, 40%) were significantly decreased after ondansetron administration but there were no significant differences among the ondansetron groups (group 2; 45%, 20%, group 3; 45%, 15%, group 4; 40%, 10%) (P < 0.05). CONCLUSIONS: The prophylactic administration of ondansetron is effective in preventing PONV during IV-PCA, but the timing of ondansetron administration has no effect on its efficacy.

Antiemetic Efficacy of Prophylactic Ondansetron in Gynecologic Patient Using Patient-Controlled Analgesia after Surgery / 대한마취과학회지

BACKGROUND: Postoperative nausea and vomiting remain troublesome problems, especially in women receiving the opioid analgesics. This study was performed to assess the antiemetic efficacy of ondansetron in patients using an intravenous patient-controlled analgesia (IV-PCA) after gynecologic surgery. METHODS: In this randomized placebo-controlled study, forty healthy gynecologic surgical patients received ondansetron 4 mg or placebo at the end of surgery. Patients in the recovery room received fentanyl by PCA which provided a bolus dose of 20 microgram, a lockout time of 6 minutes, and a basal infusion of 20 microgram/hr. We assessed the occurrence of nausea, vomiting, and the need for rescue antiemetics during the first 24 hours after operation. RESULTS: During the first 24 hr after operation, 40% of patients experienced no nausea or vomiting in the ondansetron group compared to 30% of patients in the placebo group. There was no significant difference in the incidence of nausea between groups (70% in placebo group vs 60% in ondansetron group). However, ondansetron reduced the incidence of vomiting from 50% to 15%, and the need for rescue antiemetics significantly from 25% to 0% (P< 0.05). CONCLUSIONS: Ondansetron in a dose of 4 mg does not prevent postoperative nausea during the first 24 hours after operation when used with fetanyl PCA. However, ondansetron significantly reduces the chance of postoperative vomiting and rescue antiemetics.

A Comparison of the Efficacy and Safety of Ondansetron, Droperidol and Ondansetron Plus Droperidol as Antiemetics for Elective Thyroidectomy / 대한마취과학회지

BACKGROUND: Thyroidectomy has been a surgical procedure associated with a high incidence of postoperative nausea and vomiting (PONV), and conventional antiemetics cannot prevent PONV effectively. In this study, we compared the efficacy and safety of ondansetron 70 microgram/kg, droperidol 10 microgram/kg and combination of both drugs to placebo in the prevention of PONV. METHODS: Seventy-six patients undergoing thyroidectomy were randomized to receive placebo (Group I, n=20), ondansetron 70 microgram/kg (Group II, n=19), droperidol 10 microgram/kg (Group III, n=18) and combination of both drugs (Group IV, n=19). The effects of these regimens on the incidence and severity of PONV and adverse events were analyzed for the 0 to 1 hour and 1 to 24 hours postoperative periods. RESULTS: In the 0 to 1 hour postoperative periods, the incidence of symptom free (no nausea and retching or vomiting) paients were 60% for placebo, 68.4% for ondansetron (p>0.05 versus placebo group), 88.9% for droperidol (p0.05 versus placebo group), 77.8% for droperidol (p0.05 versus placebo group), 77.8% for droperidol (p<0.05 versus placebo and ondansetron group), and 73.7% for combination of both drugs (p<0.05 versus placebo and ondansetron group). Also, there were no significant differences between the droperidol and droperidol plus ondansetron group. Among the side effects associated with antiemetics, headache and dizziness incidence was higher. CONCLUSIONS: Droperidol and combination of ondansetron plus droperidol was superior to placebo, and ondansetron for prevention of PONV during the first 24 hours postoperative period.

A Comparison of the Effects of Ondansetron and Granisetron on the Prevention of Postoperative Nausea and Vomiting after Gynecologic Surgery / 대한마취과학회지

BACKGROUND: The purpose of this study was to compare the effects of ondansetron and granisetron on the prevention of postoperative nausea and vomiting (PONV) in gynecologic patients. METHODS: In a randomized placebo-controlled study, 200 gynecologic patients were divided into 5 groups. Each patient received one of 5 medications: placebo (saline 3 ml), ondansetron 4 mg (O4), ondansetron 8 mg (O8), granisetron 1.5 mg (G1.5) and granisetron 3 mg (G3). They were administered intravenously immediately before the induction of anesthesia. A standardized inhalation anesthesia and a postoperative intravenous patient-controlled analgesia were applied. Twenty four hours after anesthesia, the incidence and severity of PONV and other adverse effects were assessed. RESULTS: The incidence of PONV was 88%, 83%, 75%, 70% and 60% in the placebo, O4, O8, G1.5 and G3 groups, respectively, which showed significantly lower value in the G3 group than in the placebo and O4 groups (P< 0.05). The severity of PONV was also significantly lower in the G3 group than in the placebo group (P < 0.05). CONCLUSIONS: In this study, granisetron 3 mg showed a better prophylactic effect in the mitigation of PONV in gynecologic patients then a placebo or ondansetron 4 mg.