The effect of ondansetron in preventing the hypotensive bradycardic events during shoulder arthroscopy done under interscalene block in the sitting position

Abstract

Purpose: This study was conducted to test whether blocking the serotonin receptors by intravenous [IV] ondansetron; can help in reducing the hypotensive bradycardic events [HB events] associated with shoulder arthroscopy done in the sitting position under interscalene plexus block [ISB]. Methods: One hundred and fifty patients, scheduled for shoulder arthroscopy in the sitting position under ISB, were randomly assigned to one of three groups receiving either: 4 mg ondansetron, or 8 mg ondansetron or saline. Results: IV injection of ondansetron 4 mg or 8 mg significantly reduced the incidence of HB events from 20.4% in the saline group to 6.1% after injection of 4 mg ondansetron and 6% after injection of 8 mg ondansetron; p value [0.030]. Conclusion: IV ondansetron either 4 mg or 8 mg reduces the HB events during shoulder arthroscopy in the sitting position under ISB.

Keywords

• Ondansetron
• Hypotensive bradycardic events
• Shoulder arthroscopy
• Sitting position
• Interscalene block