The reversing effect of ondansetron on bupivacaine-induced sciatic nerve block.

Background and Aims: This experimental study was designed to test the hypothesis that ondansetron, a selective 5-HT3 receptor antagonist, would decrease the duration of motor, sensory, and proprioception blockade in a dose-dependent fashion in a bupivacaine-induced sciatic nerve blockade. Materials and Methods: Forty-nine male Wistar Albino rats who underwent unilateral sciatic nerve block were divided into seven groups with an equal number in each group. Group B: only perineural block (PB), Group BO200: PB and perineural 200 µg ondansetron, Group BO400: PB and perineural 400 µg ondansetron, Group BO800: PB and perineural 800 µg ondansetron, Group BO800IP: PB and intraperitoneal 800 µg ondansetron, Group O800: only perineural 800 µg ondansetron, Group S: sham-operated. The rats' motor, sensory, and proprioception functions were evaluated by a blinded investigator every 10 min until they returned to normal function. The recovery times of the motor, sensory, and proprioception functions were recorded and compared. All sciatic nerves were removed and examined by electron microscopy for neurotoxic signs. Results: In which sciatic nerve block was formed with bupivacaine, the duration of the motor, sensory, and proprioception functions blockade was decreased, and the duration to return to normal functions was significantly shortened at Group BO800 (p < 0.05). According to electron microscopy results, perineural 200 µg, 400 µg, and 800 µg ondansetron were not neurotoxic. Conclusion: This is the first study showing that perineural ondansetron administration (800 µg dose) reverses the effect of the local anesthetics and shortens the duration of the motor, sensory, and proprioception functions blockade.

Prevalence study for postoperative nausea vomiting: A training hospital example.

BACKGROUND: Simplified risk models, such as the Apfel score, have been developed to calculate the risk of postoperative nausea-vomiting (PONV) for adult patients. In the absence of any risk factors, PONV risk is assumed to be 10%. While the presence of one of the four risk factors determined as female gender, non-smoking, PONV/car sickness history, and postoperative opioid use is associated with 20% risk for PONV, the risk increases by 20% with the addition of each risk factor, and reaches to 80% if four factors are present. AIM: : Our aim in this study is to investigate the prevalence of PONV, and whether the scoring systems used for nausea-vomiting in the literature are still valid. PATIENTS AND METHODS: Five groups of patients were included in the study with an Apfel score of 0, 1, 2, 3, 4. Each case was taken to the recovery room at the end of the operation. They were observed whether had nausea-vomiting was recorded according to the Abramowitz emesis score. RESULTS: While the PONV risk for women is 24.637 times higher than men, the PONV risk of those who had gynecological surgery is 6.27 times higher than that of the other type of surgery. Those who had urological surgery are 0.345 times less than the other type of surgery. Those who had lower abdominal surgery had a risk of PONV of 4.56 times higher than the others. As the duration of the case increases, the risk of PONV increases 1.01 times (P values P < 0.001, P < 0.001, P < 0.001, P = 0.048, P < 0.001, respectively). CONCLUSION: As a result, our PONV prevalence is considerably lower than the frequency rates mentioned in the literature. PONV scoring systems need long-term studies with larger populations to be updated.