COMPARISON OF PROPHYLACTIC USE OF INTRAVENOUS DEXMEDETOMIDINE AND MAGNESIUM SULPHATE FOR PREVENTION OF SHIVERING DURING TRANSURETHRAL RESECTION OF THE PROSTATE (TURP) UNDER SPINAL ANAESTHESIA: A PROSPECTIVE RANDOMIZED DOUBLE-BLIND CONTROLLED STUDY

Abstract

Background: Transurethral resection of the prostate (TURP) is routinely performed under spinal anesthesia. The profound sympathetic nerve blockade, coupled with continuous room-temperature irrigation fluid, acts as a massive thermal drain, rapidly stripping the body of thermal energy and leading to a remarkably high incidence of post-spinal shivering. Aims and Objectives: This study aimed to compare the prophylactic efficacy of intravenous dexmedetomidine and intravenous magnesium sulfate against a normal saline control in preventing post-spinal anaesthesia shivering and to evaluate hemodynamic stability, sedation, postoperative analgesia, and complication profiles. Materials and Methods: This prospective, randomized, double-blind controlled trial was conducted in 90 male patients with ASA Grade I or II who were scheduled for elective TURP under subarachnoid block. Patients were randomized into three groups of 30 patients each. Group C received 100 ml of 0.9% Normal Saline; Group D received 0.5 µg/kg of dexmedetomidine in 100 ml of normal saline, and 30 mg/kg of magnesium sulfate in 100 ml of normal saline. All study drugs were administered intravenously over 10 min before the subarachnoid block. Results: The demographic and surgical profiles were statistically comparable across all groups. Dexmedetomidine (Group D) and magnesium sulfate (Group M) demonstrated superior prophylactic efficacy against shivering compared with the control group, with 93.3% of patients in Group D and 83.3% in Group M experiencing Grade 0 (no shivering). Group D provided profound conscious sedation (mean Ramsay Score 3.60 ± 0.67) and the most significant prolongation of postoperative analgesia (VAS 13.07 ± 4.05 at 4 hours, p<0.001). However, Group D exhibited a higher incidence of hypotension (36.7%) and bradycardia (10.0%), whereas Group M maintained superior chronotropic stability. Conclusion: Dexmedetomidine and magnesium sulfate are highly effective in preventing shivering associated with spinal anesthesia in patients with TURP. Dexmetatomidine offers superior postoperative analgesia and excellent cooperative sedation, whereas magnesium sulfate provides potent anti-shivering action while maintaining superior hemodynamic stability.