Efficacy Of Dexmedetomidine As An Anti Shivering Agent Following Spinal Anaesthesia In Adults, A 1 Year Double Blinded Placebo Controlled Randomized Trial

Abstract

Background and objectives Shivering after spinal anaesthesia is a common complication, which we come across everyday as anaesthesiologists. It is physiologically and emotionally unpleasant for the patient and also makes us think that there is a lacuna in our management. Approximate range of its occurrence is between 5 to 65 % in patients recovering from anaesthesia. The main objective of this study was to assess the efficacy of dexmedetomidine as an anti-shivering agent following spinal anaesthesia in adults. Methodology: The study was conducted in the Department of Anaesthesiology, KLE’S Dr. Prabhakar Kore Hospital and Medical Research Centre, Nehrunagar, Belgaum in patients undergoing infraumbilical surgeries between January 2013 to December 2013. It was conducted after the approval by the ethical committee and written informed consent was taken from the participants who were to be included in this study. ASA I and II patients in the age group of 18 to 60 years, with the procedure time being at least 45 minutes to 1 hour were included in the study. They were then randomly divided into two groups: Group A (Dexmedetomidine) and Group B (Placebo) using a computer generated table. Tympanic membrane temperature was recorded using infrared thermometer before the start of procedure, after which shivering and sedation were recorded every 15 minutes according to the below mentioned scales: Shivering was graded on a scale: 0 = no shivering, 1 = piloerection or peripheral vasoconstriction but no visible shivering, 2 = muscular activity in one muscle group, 3 = muscular activity in more than one muscle group but not generalized, 4 = shivering involving the whole body. Degree of sedation on a 5-point scale: 1 = fully awake and oriented, 2 = drowsy, 3 = eyes closed but open on command, 4 = eyes closed but open to mild physical stimulation, 5= eyes closed and unresponsive to mild physical stimulation. If greater than grade 3 shivering was observed in any of the groups, rescue drug Tramadol 1mg/kg was given by intravenous route. Any side effects of the drugs were noted. Results Our study showed that Dexmedetomidine was effective in prevention of shivering throughout a period of 180 minutes, however the median grades of shivering were insignificant between the two groups after an interval of 150 minutes. The number of patients receiving Dexmedetomidine who showed no occurrence of shivering were 27 out of 30 ( 90 %). In the placebo group only 15 out of 30 (50 %) did not experience shivering, anytime throughout the procedure. Conclusions Dexmedetomidine 1µg/kg over 20 minutes is a useful drug in prevention of shivering in patients undergoing infra umbilical surgeries under spinal anaesthesia. Dexmedetomidine was found to be effective to combat shivering and can be recommended in prevention of shivering, keeping in mind hypotension and bradycardia as its side effects.