Efficacy of prophylactic use of hydrocortisone and low dose ketamine for prevention of shivering during spinal anesthesia

Background
Spinal anesthesia is commonly associated with shivering. The aim of this study was to compare the efficacy of i.v. hydrocortisone with i.v. low dose ketamine or placebo for prevention of shivering during spinal anesthesia.
Method
In this prospective, randomized, double-blind study, 90 female patients ASA I–II age 30–60 years old, undergoing posterior vaginal repair surgeries under spinal anesthesia with 3 ml heavy bupivacaine 0.5% (15 mg), patients were randomly allocated into one of three groups, (Group S,  = 30) (control) received saline, (Group K,  = 30) received ketamine 0.25 mg kg or (Group H,  = 30) received hydrocortisone 2 mg kg, the drugs were given i.v. just after spinal anesthesia with recording of vital signs, and core temperature every 15 min intraoperative and every 10 min in recovery room. The incidence and intensity of shivering, number of patients received meperidine, sensory level, motor block grade, and side effects (hypotension, hypertension, tachycardia, nausea and vomiting, sedation and hallucinations) were also recorded.
Results
Incidence of shivering were significantly reduced in k and H groups being 20% and 23.3% respectively compared to S group ( < 0.05). Patients received meperidine to control shivering were significantly low in Groups K and H compared to group S ( < 0.05), with no difference between Groups K and H.
Conclusions
The prophylactic administration of low dose ketamine (0.25 mg kg) and hydrocortisone (2 mg kg) were comparable in reducing the incidence of shivering and both had significant antishivering effect compared to placebo, in female patients under spinal anesthesia for posterior vaginal repair surgeries.