Effects of intraoperative Magnesium sulfate infusion on emergency agitation during general anesthesia in patients undergoing radical mastectomy: a randomized controlled study

BACKGROUND: Emergency agitation is a common postoperative complication in patients under general anesthesia, which can lead to unpredictable damages such as shedding of drainage tube and bleeding from the wound. The purpose of the study is to investigate whether intraoperative infusion of Magnesium Sulfate reduces the incidence of emergency agitation (EA) in patients undergoing radical mastectomy, and to evaluate its safety and efficacy. METHODS: A total of 70 patients were randomly assigned to two groups: the Magnesium group (M group) and the control group (C group). After a routine intravenous anesthetic induction, patients in the M group received a 30 mg/kg bolus of intravenous magnesium during the first hour and then a continuous infusion of 10 mg/kg ×h until the end of the surgery, patients in the C group received 0.9% saline at the same volume and rate. The sedation-agitation scale (SAS) and the visual analogue scale were used to assess agitation and pain, respectively. RESULTS: Compared to the C group, the M group reduced the incidence of EA significantly (odds ratio 0.26, 95% confidence interval 0.09–0.71, P = 0.009). The postoperative pain score of the magnesium sulfate group(0(0,1)) was lower than that of the control group(2(0,3)) at T0 (P = 0.011). Additionally, the M group required a lower dosage of remifentanil during surgery compared to the C group(300.4 ± 84 versus 559.3 ± 184 µg, respectively, P<0.001). CONCLUSIONS: the intraoperative infusion of magnesium sulfate is a safe and effective method for reducing the incidence of emergency agitation in patients undergoing radical mastectomy. TRAIL REGISTRATION: The study was registered in Chictr.org with the identifier: ChiCTR2300070595 on 18/04/2023.