Intravenous low dose Ketamine injection versus Dexmedetomidine infusion for prevention of intraoperative shivering during spinal anesthesia

INTERVENTION: Patients included in group D received Dexmedetomidine infusion (loading dose of 1mcg/kg over 10 minutes followed by a maintenance dose of 0.4mcg/kg/h) started immediately after giving spinal anesthesia for elective lower abdominal surgeries and elective lower limb orthopedic surgeries to control post‐spinal anesthesia shivering and maintained until completion of surgery. CONDITION: post‐spinal anesthesia shivering PRIMARY OUTCOME: measurement of post‐spinal anesthesia shivering using 5 points rating scale, with grade 0 indicating no shivering to grade 4 indicating gross muscle activity involving the whole body. SECONDARY OUTCOME: Sedation score measurement of hemodynamic parameters (heart rate from ECG monitor, temperature by axillary thermometer, mean arterial pressure by automated non‐invasive blood pressure monitoring, SPO2 by pulse oximetry) INCLUSION CRITERIA: Patients undergoing elective lower abdominal surgery and elective orthopedic lower limb surgery were included in the study. Patients selected were American Society of Anesthesiologists (ASA) I and II physical status.