Objective: Evaluate the effect of oral rehydration with 10% CHO drink before anesthesia on incidence and severity of postoperative nausea and vomiting (PONV) after spinal morphine injection.

Material and Method: One hundred patients scheduled for unilateral total knee replacement (TKR) were randomly divided into two equal groups (n = 50 each). Group I patients received 400 ml 10% CHO drink the preoperative night and 2-hour before anesthesia, whereas Group II patients served as control. Spinal anesthesia for all patients contained 0.5% bupivacaine 2.0 to 3.5 ml plus morphine 0.2 mg. Pain therapy was standardized with femoral nerve block, local infiltration, intravenous parecoxib, and oral paracetamol. Incidence and severity of PONV within 24 hours were recorded. In addition, preoperative intensity of thirst and hunger, dry lips and throat, and anxiety was also recorded.

Results: Incidence and severity of PONV (81.2% vs. 72.0%, p = 0.536) as well as preoperative thirst, hunger, dry lips, and throat were not different between the groups.

Conclusion: Preoperative oral rehydration with carbohydrate drinks had no positive effect on PONV nor patients’ comfort.

Keywords: spinal morphine, carbohydrate drink, postoperative nausea and vomiting (PONV)