The Effect of Clonidine and Tramadol on Post-spinal Anaesthesia Shivering in Hysterectomy Patients: A Comparative Study

Introduction: Spinal anaesthesia is most commonly used as a secure anaesthetic method in elective and emergency operations. Shivering is noted in 40%–70% of patients undergoing surgery under spinal anaesthesia. The study aims to compare the efficacy, haemodynamic effects and side effects of clonidine with tramadol for the control of shivering. Materials and Methods: This prospective study was conducted from April 2016 to November 2016. Using a convenient sampling technique, a total of 60 adult patients of the American Society of Anaesthesiologists (ASA) physical status Grade I or II, aged ≥18 years, of either sex who were scheduled hysterectomy administered with clonidine vis-à-vis tramadol for spinal anaesthesia were selected for the study after informed consent. All the patients were randomly allocated into one of the two groups using computer generated random number table: Group C: Injection clonidine 75 µg slow intravenous (IV) injection and Group T: Injection tramadol 1 mg/kg slow IV injection. Results: Non-significant association was found between age, ASA grade, level of sensory block, shivering grade and mean systolic blood pressure amongst the participants of group clonidine and tramadol. Group C had significantly early control of shivering, less time for complete loss of shivering and fewer adverse events were noted compared to the tramadol group. Conclusion: Both clonidine (75 µg) and tramadol (1 mg/kg) effectively treat patients with post-spinal anaesthesia shivering, but tramadol takes longer time for complete cessation of shivering than clonidine. Clonidine offers better thermodynamics than tramadol, with fewer side effects. The more frequent incidence of the side effects of tramadol, such as nausea, vomiting and dizziness, may limit its use as an anti-shivering drug.