Evaluation of Two Doses of Intrathecal Clonidine on Analgesia and Haemodynamic Profile in Elderly Patients Undergoing Endoscopic Bladder SurgeriesA Randomised Clinical Trial

Abstract

Introduction: Endoscopic bladder surgeries like Transurethral Resection Of Prostrate (TURP) and Transurethral Resection Of Bladder Tumour (TURBT) are performed preferably under spinal anaesthesia, using local anaesthetic like bupivacaine along with an adjuvant. Of these adjuvants used, clonidine is gaining popularity because of its safety and various advantages associated with its use. However its effect on haemodynamics, effect on block characteristics and analgesia in elderly patients has not been studied extensively. Aim: To evaluate the analgesic efficacy and safety of clonidine 30 µg and 50 µg, in elderly patients undergoing endoscopic bladder surgeries. Materials and Methods: It was a double blinded randomized control trial, conducted in Department of Anaesthesia, University College of Medical Sciences, Delhi, India, from September 2008 to October 2011. Sixty American Society of Anaesthesiology (ASA) grade I and II patients, of age 50-80 years, undergoing endoscopic bladder surgeries, were randomly allocated into three groups of 20 each. Group C received 12.5 mg of 0.5 % heavy bupivacaine (2.5 mL) without clonidine, while group A and group B received 30 µg and 50 µg, respectively of clonidine. Intraoperative non invasive and invasive haemodynamic monitoring was done. The duration of analgesia (the time from the intrathecal injection to Visual Analog Scale (VAS) score greater than 0 and Bromage Scale 3), quality of anaesthesia and haemodynamic were compared between the three groups. Analysis of variance (ANOVA) for repeated measures was used for analysing the collected data. Tukey’s Honest Significant Difference (HSD) test was applied as post hoc test whenever applicable. Results: The mean duration of complete analgesia was 3.32±1.80 hours in group A, 6.30±1.45 hours in group B, and 2.22±0.92 hours in group C. The duration of complete analgesia was significantly longer in group A and B, when compared to group C. The mean duration of effective analgesia was 6.05±0.88 hours in group A, 8.65±1.75 hours in group B, and 4.68±1.77 hours in group C. The duration of effective analgesia was significantly longer in group A and B, as compared to group C. Following intrathecal injection, there was no significant difference in heart rate, Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP), cardiac output, stroke volume, systemic vascular resistance in between groups. There were no significant side effects in any of the groups. Conclusion: Intrathecal clonidine in a dose of 30 µg and 50 µg provides faster onset, better quality and prolonged duration of block with stable haemodynamic and minimal side effects in patients undergoing endoscopic bladder surgeries.