Purpose: Some antiemetics are effective in the treatment of postoperative pain and shivering, as well as for postoperative nausea and vomiting (PONV). The aim of this study was to investigate the effects of ramosetron and dexamethasone on PONV, pain, and shivering and to determine the correlations between nausea, pain, and shivering.
Methods: For this study, 123 patients scheduled for thyroid surgery were randomly allocated to one of three groups: the control group (group C, n = 41), dexamethasone group (group D, n = 41), or the ramosetron group (group R, n = 41). The patients were treated intravenously with 2 mL of 0.9 % NaCl, 2 mL of 5 mg/mL dexamethasone, or 2 mL of 0.15 mg/mL ramosetron immediately after anesthesia.
Results: The overall incidence and severity of postoperative nausea and the level of antiemetic consumption were significantly lower in group R compared with group D, and these parameters were significantly lower in groups R and D than in group C. There were significant differences in the incidence and severity of shivering, severity of pain, and analgesic consumption between group C and group R or D, but the incidence of shivering, pain severity, and analgesic consumption did not differ between groups R and D. The severity of shivering was significantly lower in group R than in group D. The correlation coefficients for shivering and pain, shivering and nausea, and pain and nausea were 0.210 (P = 0.010), 0.106 (P = 0.198), and 0.190 (P = 0.035), respectively, in group C.
Conclusions: Two antiemetic drugs, ramosetron and dexamethasone, significantly reduced the incidence and severity of postoperative nausea and the need for administration of rescue antiemetic drugs. Furthermore, both drugs effectively decreased the severity of pain and shivering. Ramosetron was superior to dexamethasone for reducing nausea, antiemetic consumption, and the severity of nausea, but not for reducing the incidence of shivering. Further studies are required to elucidate the correlations between postoperative nausea, pain, and shivering, as a statistically significant but weak correlation was shown in the present study.