Combination therapy in the prevention of PONV after strabismus surgery in children: granisetron, ondansetron, midazolam with dexamethasone.

BACKGROUND Pediatric strabismus surgery is commonly associated with higher incidence of postoperative nausea and vomiting (PONV). Mixtures of different classes of antiemetics have been used successfully to decrease the incidence of PONV but there was no agreement on the optimal combination. The aim of this study was to investigate the effect of granisetron, ondansetron, midazolam combination with dexamethasone in the prevention of PONV following strabismus repair in pediatric population. METHOD Healthy 100 children ASA class I and II aged 4-12 years, scheduled for elective strabismus surgery, were enrolled in this study. No premedications were given anesthesia was induced by inhalational technique using sevoflurane, nitrous oxide and oxygen mixture. After induction, fentanyl and atracurium were given and an endotracheal tube was inserted. Patients were randomly divided into four groups which received intravenously either: Placebo, or a combination of granisetron 10 microg/kg(-1), ondansetron 50 microg/kg(-1), midazolam 50 microg/kg(-1), plus dexamethasone 0.5 mg/kg(-1) after induction of anesthesia and before start of surgery. All episodes of PONV during the first 24 hours after anesthesia were recorded. RESULTS The incidence ofpostoperative nausea was 48%, 8%, 12% and 0% while the incidence of vomiting was 52%, 12%, 4% and 0% in placebo, granisetron, ondansetron, midazolam and dexamethasone combination groups respectively. No difference was detected between combination groups (P value > 0.05). CONCLUSION Prophylactic administration of either of either granisetron, ondansetron, midazolam combined with dexamethasone markedly decreases the incidence of PONV following strabismus surgery in pediatrics. All combinations are equally effective.