ADVANCES IN ANTIEMETIC THERAPY

Preoperative anxiety and postoperative nausea and vomiting in children: is there an association?

We performed a cross-sectional study to explore a potential association between preoperative anxiety and postoperative nausea and vomiting (PONV). The study enrolled 51 unpremedicated children 5-16 yr old undergoing outpatient surgery and standardized general anesthesia. Anxiety of children was assessed in the preoperative holding area and during the induction of anesthesia. The incidence of nausea and vomiting was documented in the postanesthesia care unit (PACU) and 24 h postoperatively (POD#1). In addition to univariate analysis, we used multivariate logistic regression models, wherein the dependent variable was the presence or absence of PONV and the independent variables included potential confounders such as age, sex, and perioperative opioid consumption. Univariate analysis showed that children who experienced nausea (32 +/- 5 vs 31 +/- 4, P = ns) or vomiting (32 +/- 4 vs 32 +/- 5, P = ns) in the PACU did not differ significantly in their anxiety before surgery. A multivariate model, in which the dependent variable was the presence or absence of vomiting at POD#1 and the independent variables included preoperative anxiety, age, sex, and opioid consumption, indicated that preoperative anxiety does not predict the occurrence of nausea and vomiting (P = ns). We conclude that children's anxiety in the preoperative holding area has no predictive value for the occurrence of PONV in the PACU or POD#1.

IMPLICATIONS

This study was performed to explore a possible association between children's anxiety before surgery and postoperative nausea and vomiting. We found that controlling for confounding variables, anxiety in the preoperative holding area has no predictive value for the occurrence of postoperative nausea and vomiting.

Tropisetron or ondansetron compared with placebo for prevention of postoperative nausea and vomiting

In a prospective, randomized, double-blind, placebo-controlled, multicentre study, the efficacy of prophylactic tropisetron (2 mg) or ondansetron (4 mg) for the prevention of post-operative nausea and vomiting after abdominal or non-abdominal surgery with general balanced anaesthesia was studied in 842 ASA I-III patients. In patients undergoing abdominal surgery, ondansetron and tropisetron reduced the frequency of emetic episodes compared with the placebo (29%, 30% vs. 42% respectively). In men, neither tropisetron nor ondansetron had an effect different from the placebo, whereas in women both drugs led to lower rates of emetic episodes and nausea. In comparison with abdominal surgery, fewer patients in the non-abdominal surgery subgroup had emetic episodes (42% vs. 23% in the placebo group). However, neither tropisetron nor ondansetron was significantly different from the placebo in this patient subgroup. In conclusion, for patients at increased risk of post-operative nausea and vomiting, a prophylactic therapy at the lowest effective dose with tropisetron or ondansetron may be useful.

Recovery profile after desflurane with or without ondansetron compared with propofol in patients undergoing outpatient gynecological laparoscopy

We studied the effect of combining prophylactic ondansetron (4 mg intravenously [IV]) to desflurane-based anesthesia in 90 ASA grade I or 11 women undergoing outpatient gynecological laparoscopy. Recovery after anesthesia, with special focus on postoperative nausea and vomiting (PONV), was assessed. Control groups received a similar desflurane anesthetic (placebo) or a propofol-infusion-based (active control) anesthetic. The study design was randomized, controlled, and double-blind (regarding ondansetron) and single-blind (regarding the anesthetic technique). Early recovery (eye opening, orientation, following commands, sitting) was similar in the three groups. However, overall home readiness (toleration of oral fluids, walking, pain tolerable by oral analgesics, no or only mild nausea) was achieved faster in the desflurane group receiving ondansetron (109 [21-937] min, P < 0.01) and in the propofol group (110 [33-642] min, P < 0.001) when compared to the desflurane only group (372 [45-723] min) (median [range]). The total incidence of PONV in the desflurane-only group was 80% (P < 0.01), compared to 40% and 20% in the desflurane group receiving ondansetron and the propofol group, respectively. The postoperative antiemetic requirements were consistently and significantly (P < 0.01) higher in the desflurane-only group compared to the other two groups. Postoperative sedation, analgesic requirements, and psychomotor recovery (assessed by the Maddox Wing and the Digit Symbol Substitution Tests) were similar in the three groups. Our results suggest that in order to achieve a propofol-like recovery profile in patients with a high likelihood of PONV, desflurane should be combined with a potent antiemetic (e.g., ondansetron).