Postoperative nausea and vomiting following 8% sevoflurane anaesthesia

Dexamethasone Reduces Postoperative Nausea in Pediatric Upper Endoscopy With Deep Sedation: A Randomized Controlled Trial

OBJECTIVES

We aimed to evaluate the effect of a single dose of preoperative dexamethasone on postoperative nausea and vomiting (PONV), a frequent complication and a major cause of delayed recovery in pediatric upper gastrointestinal endoscopy (UGIE) under sedation.

METHODS

In this double-blind randomized controlled study, 98 children aged 2 to 14, with American Society of Anesthesiologists status I to II, and undergoing elective UGIE with deep sedation were included and randomly assigned to 2 groups. Preoperatively, after anesthesia induction with sodium thiopental and maintenance with sevoflurane, patients in the intervention (n = 49) and control (n = 49) groups, respectively received 0.1 mg/kg i.v. dexamethasone and 2 cm i.v. 0.9% saline. Postoperatively, PONV incidence was measured as the primary outcome.

RESULTS

PONV incidence was significantly less in dexamethasone group (8.2%) compared to the control group (26.5%) (difference = 18.3%, 95% confidence interval: 3.4%-33%, P = 0.016). For secondary outcomes, between-group differences were not statistically significant: incidence of bronchospasm or laryngospasm (both 4.1%, P = 1); emergence delirium assessed with Pediatric Anesthesia Emergence Delirium scale (5.9 ± 3.4 vs 5.7 ± 3.2, P = 0.751); Modified Aldrete score at 0 minutes (9.4 ± 0.8 vs 9.3 ± 0.9, P = 0.909) and at 5 minutes (9.5 ± 0.7 vs 9.4 ± 0.9, P = 0.527); and recovery time (21.1 ± 6.6 vs 23.4 ± 8.6 minutes, P = 0.130).

CONCLUSIONS

A single preoperative dose of i.v. dexamethasone reduces PONV in children undergoing elective UGIE with deep sedation, but has no significant effect on the patient recovery time or the incidence of postoperative bronchospasm or laryngospasm and emergence delirium.

Midazolam vs ondansetron for preventing postoperative nausea and vomiting: a randomised controlled trial

We compared the prophylactic anti-emetic efficacy of midazolam and ondansetron in 90 patients scheduled for minor gynaecological (hysteroscopy) or urological (ureteroscopy) procedures planned to last 1-2 h under sevoflurane anaesthesia with spontaneous ventilation of the lungs via a laryngeal mask airway. Midazolam 2 mg or ondansetron 4 mg were administered intravenously 30 min before the end of surgery. The proportions of patients who experienced postoperative nausea and vomiting in the first 24 h (30% and 27% for the midazolam and ondansetron groups, respectively) were similar in the two groups. The incidence of postoperative nausea and vomiting was significantly smaller in both groups than predicted according to the patients' underlying risks (midazolam group: p = 0.018; ondansetron group: p = 0.017). There were no significant differences in average sedation scores or pain scores. Treatment using ondansetron for anti-emetic prophylaxis did not provide a superior benefit compared to midazolam in the present study.

Sevoflurane vs. isoflurane: a clinical comparison in day surgery

Discharge times after ambulatory surgery are determined by postoperative complications and in particular by the presence and severity of nausea and vomiting. Sevoflurane has become a popular agent for day-case surgery despite little evidence of clear advantages over current alternatives. We compared this agent with isoflurane in day-case patients undergoing knee arthroscopy in order to quantify the incidence of complications associated with each agent. One hundred and eighty patients received a standardised anaesthetic induction with propofol and fentanyl followed by maintenance with either isoflurane or sevoflurane. Standardised postoperative analgesic and anti-emetic drugs were prescribed. Any intra-operative cardiovascular or respiratory instability was recorded. After surgery, nausea, vomiting and pain were assessed. Almost all patients made an uneventful recovery and were discharged as scheduled. There was a significantly higher incidence of complications in the sevoflurane group. These included the presence of nausea and vomiting, and cardiovascular and respiratory complications. We found nothing to commend the routine use of sevoflurane rather than isoflurane in the context of day case anaesthesia.