Comparative study of granisetron versus pethidine for the prevention of perioperative shivering under spinal Anesthesia

Aims: Shivering, the "big little problem," has an incidence of 19-33% following spinal anesthesia. Recently, studies showed the involvement of serotonergic system in the control of postanesthetic shivering. Pharmacological management includes opioids (pethidine) and nonopioids like 5-HT3 receptor antagonists (ondansetron and granisetron). Pethidine which is considered as a time-tested drug for control of shivering can have adverse effects such as respiratory depression, nausea, and vomiting. This study was performed to compare the effect of prophylactic granisetron versus pethidine in prevention of perioperative shivering in patients under spinal anesthesia. Settings and Design: A prospective randomized, double blinded study was conducted on 60 patients of ASA I and II physical status aged between 20-50 years scheduled for elective lower abdominal surgeries under spinal anesthesia. Subjects and Methods: After obtaining ethical committee clearance and patient consent, sixty American Statistical Association Grade I and II patients, aged 20-50 years scheduled for elective lower abdominal surgeries under spinal anesthesia were recruited for a randomized double-blinded study divided into Group G and Group P and received intravenous (IV) granisetron 40 mcg/kg and pethidine 0.4 mg/kg, respectively. Perioperatively, vitals and core temperature were monitored and shivering was assessed using 5-item scale once in every 15 min up to 6 h. Statistical Analysis: The results were analysed using Statistical Package for Social Science software. Results: Of the sixty patients we studied, the demographic profile between the two groups was comparable. Six patients had shivering in each group. The mean temperature at which patient developed shivering was 36.31°C in Group G and 35.85°C in Group P. The mean time of onset for shivering to occur in Group G was 95 min and in Group P was 65 min. None of the patients received rescue drug. Patients in both the groups were hemodynamically stable. Conclusions: Prophylactic granisetron 40 μg/kg IV is as effective as pethidine 0.4 mg/kg IV in preventing perioperative shivering following spinal anesthesia and also reduces the need of antiemetics.