1. Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine
2. Department of Anesthesiology and Pain Medicine and Anesthesia and Pain Research Institute, Yonsei Cardiovascular Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea.
Background: Postoperative sore throat (POST) is a frequent complication of tracheal intubation, particularly after surgery in the prone position. We designed this study to validate the non-inferiority of magnesium sulphate against dexamethasone for prevention of POST after lumbar spinal surgery.
Methods: One hundred and forty-six patients were randomly allocated to receive either magnesium or dexamethasone. Before anesthetic induction, the magnesium group (n = 73) received magnesium sulphate 30 mg/kg followed by 10 mg/kg/h by continuous infusion until the end of surgery. The dexamethasone group (n = 73) received dexamethasone 8 mg. The primary endpoint was the overall incidence of POST, which was assessed serially over 48 hr postoperatively. The predefined margin of non-inferiority for magnesium against dexamethasone was 15%.
Results: Overall incidences of POST at rest (50.7% versus 49.3% in the magnesium and dexamethasone group, respectively, p = 0.869) and swallowing (65.8% versus 61.6% in the magnesium and dexamethasone group, respectively, p = 0.606) were not different between the groups. The upper limit of the 90% confidence interval, which must be lower than the predefined margin of non-inferiority to prove the non-inferiority of magnesium sulphate against dexamethasone, for at rest and swallowing were 14.97% (p = 0.0496) and 17.19% (p = 0.0854), respectively. The incidences and severities of POST and hoarseness were also not different between the groups throughout the study period.
Conclusions: Prophylactic magnesium sulphate appears to be non-inferior to dexamethasone for the prevention of POST at rest in patients undergoing lumbar spinal surgery in the prone position.
Keywords: Dexamethasone, Magnesium, Postoperative sore throat, Prone position