Effects of Intravenous Ketamine and Tramadol on the Amount of Antiemetics Used in General Anesthetic Patients

Postoperative nausea and vomiting (PONV) is the most common complication after surgery that might prolong discharge time and cause some morbidity.

This double-blind placebo-controlled randomized clinical trial study was conducted on 150 patients of both sexes aged 18-65 years. Patients were all ASA (American Society of Anesthesiologists) class I or II candidate for general anesthesia. They were randomly divided into three groups of ketamine, tramadol, and normal saline. We injected 2 cc of normal saline and 0.5 mg/kg of ketamine and 0.3 mg/kg of tramadol, respectively to the saline, ketamine, and tramadol groups. All injections were performed 30 minutes before the surgery ended. All patients were monitored for nausea and vomiting in the recovery room and during the first 24 hours after surgery. Data was analyzed by SPSS16.

The three groups did not differ significantly regarding patient characteristics. Average severity of PONV was 0.31 ± 1.2, 0.78 ± 1.89, and 1.25 ± 2.2 in the ketamine, tramadol, and saline groups, respectively (P = 0.24).

Our study showed ketamine to reduce PONV. In addition, tramadol did not increase PONV.