Drug and Dose Adjustment in Preventing Postoperative Nausea and Vomiting

Drug and Dosage Adjustment in Preventing Postoperative Nausea and Vomiting in Adult Patients Undergoing Elective Surgery Under General Anesthesia

The aim is to evaluate the effectiveness of different regimens of prophylactic Ondansetron, Dexamethasone, or both, on the incidence and severity of post-operative nausea and vomiting.

Patients will be randomized to one of four arms: Ondansetron (4O-PE: 4 mg Ondansetron pre-emergence, 8O-PE: 8 mg Ondansetron pre-emergence, 4O-PI: 4 mg Ondansetron pre-incision, 8O-PI: 8 mg Ondansetron pre-incision), Dexamethasone (4D-PE: 4 mg Dexamethasone pre-emergence, 8D-PE: 8 mg Dexamethasone pre-emergence, or 4D-PI: 4 mg Dexamethasone pre-incision, or 8D-PI: 8 mg Dexamethasone pre-incision), Combination Therapy group (4O-PI+8D-PI: 4 mg Ondansetron pre-incision + 8 mg Dexamethasone pre-incision, 4O-PI+8D-PE: 4 mg Ondansetron pre-incision + 8 mg Dexamethasone pre-emergence, 4 O-PE+8D-PI: 4 mg Ondansetron pre-emergence + 8 mg Dexamethasone pre-induction, 4 O-PE+8D-PE: 4 mg Ondansetron pre-emergence + 8 mg Dexamethasone pre-emergence), and Placebo group 2 ml Saline 0.9%. Primary outcome will be the incidence of PONV in the PACU prior to discharge.

Inclusion Criteria:

• ASA grade I and II
• Aged 18-70 years
• Patients scheduled for elective surgery under general anesthesia

Exclusion Criteria:

• All patients who received antiemetics or cortisone within 48 hr before surgery
• Pregnant, breast feeding ladies
• Any patient with BMI (Body Mass Index) > 34 kg/m²
• Patient with gastrointestinal, hepatic, renal, mental or psychiatric illnesses were also excluded from the study protocol.