Background: Postoperative nausea and vomiting (PONV) is one of the main causes of patient and family dissatisfaction, which may delay the onset of oral intake and postpone discharge. In pediatric patients, the incidence of PONV is high, and in some studies it can reach values of 70%. Strabismus surgery is considered an independent risk factor for PONV. Palonosetron is a second generation antiemetic drug, 5-hydroxytryptamine receptor antagonist, with a long half-life, which allows single dose administration and has been shown to be safe and effective in the treatment of chemotherapy induced nausea and vomiting, and has been used with satisfactory results in the prophylaxis of PONV in adult and pediatric patients. Studies involving palonosetron are still scarce.

Prospective, double-blind study comparing Palonosetron and Dexamethasone in the prophylaxis of Post-Operative Nausea and Vomiting in children submitted to Strabismus surgery ABSTRACT Background: Postoperative nausea and vomiting (PONV) is one of the main causes of patient and family dissatisfaction, which may delay the onset of oral intake and postpone discharge. In pediatric patients, the incidence of PONV is high, and in some studies it can reach values of 70%. Strabismus surgery is considered an independent risk factor for PONV. Palonosetron is a second generation antiemetic drug, 5-hydroxytryptamine receptor antagonist, with a long half-life, which allows single dose administration and has been shown to be safe and effective in the treatment of chemotherapy induced nausea and vomiting, and has been used with satisfactory results in the prophylaxis of PONV in adult and pediatric patients. Studies involving palonosetron are still scarce.

Objective: The study aims to compare the incidence of PONV after intravenous administration of palonosetron or dexamethasone in pediatric patients undergoing elective strabismus surgery under general anesthesia.

Materials and Methods: This prospective, double-blind study consist of 80 patients of both genders, classified as ASA grade I and II, ranging in age from 2 to 15 years, scheduled for elective strabismus surgery at Hospital Universitário Antonio Pedro(HUAP), after consent by their parents. Patients will be randomized into two groups of 40 patients each. Group P will receive intravenous dose of palonosetron (1 mg.kg-1), and Group D will receive dexamethasone (0.2 mg.kg-1) after induction of anesthesia. Pacients will be observed for 6 hours before discharge and post-discharge symptoms will be assessed through telephone survey after 24 and 48 hours. At the end of the study, results will be compiled and statistical analysis will be done by using Mann-Whitney test, Chi-squared test and Fisher test.

Inclusion Criteria:

• Children undergoing elective strabismus surgery
• Physical state according to an American Society of Anesthesiologists (ASA) I and II

Exclusion Criteria:

• Children nor involved in surgery
• Participation in another study in the last month
• Previous history of PONV
• Occurrence of episodes of nausea or vomiting in the last 24 hours before surgery
• Chronic use of corticosteroids
• Previous history of motion sickness
• Use of psychoactive drugs or any other medicine with an antiemetic effect;
• Known hypersensitivity to any study medication
• Severe diseases in organs such as kidney, liver, lung, heart, brain and bone marrow

Double-blinded