A CLINICAL STUDY OF CLONIDINE 0.5g/kg AND 1g/kg AS AN ADJUVANT TO 0.25% BUPIVACAINE IN PAEDIATRIC CAUDAL BLOCK FOR CIRCUMCISION

Abstract

BACKGROUND AND OBJECTIVES: Regional techniques are now increasingly being used in pediatric patients to provide post-operative analgesia. Caudal epidural block is one of the most common regional techniques used in pediatric anesthesia. AIMS AND OBJECTIVES: 1.To assess the safety and efficacy of 0.25% Bupivacaine with Clonidine in pediatric caudal block. 2. To compare the duration of analgesia with different dosages of Clonidine as an adjuvant. METHODS: This study was conducted in the department of Anesthesiology with cooperation from the department of Pediatric Surgery at KIMS hospital and research centre, Bengaluru from December 2008 to September 2010.Study design: Comparative Randomized study. Sampling method: Purposive sampling. Statistical analysis: Using Student's t test and chi-square test. In this study caudal block was givenin 60 children aged between 1-6years, posted for circumcision who were divided into two groups. Group I consisting of 30 children who received0.25% Bupivacaine 0.5ml/kg with Clonidine 0.5µg/kg as adjuvant and group II consisting of 30 children who received 0.25% Bupivacaine 0.5ml/kg with Clonidine 1μg/kg. All the children were premedicated with Inj. Atropine 0.01mg/kg and Inj. Midazolam 0.1mg/kg. Caudal block was performed in all children after induction with Propofol and maintained on spontaneous ventilation with Oxygen, Nitrous oxide and Halothane. Intraoperatively the hemodynamic changes were monitored by recording the heart rate, blood pressure and SPO2 and the onset of action was noted. Postoperatively the duration of sedation was assessed using the sedation score, duration of analgesia using the observational pain scale, motor block using the modified Bromage scale and any complications that occurred were noted. RESULTS: Intraoperatively there was a minimal fall in the heart rate and no significant variation in the mean arterial pressure in both the groups. Postoperatively all the vital parameters were unaltered until the child experienced pain when there was an increase in heart rate. The duration of sedation was 134.00±18.02mins in group I and 139.50±20.52mins in group II. We did not observe any case of motor block in both the groups. The duration of analgesia was observed as 423.50±22.86mins in group I and 456.00±38.52mins in group II which was statistically significant (p<0.001).CONCLUSIONS: Caudal epidural block using Clonidine as an adjuvant to Bupivacaine prolongs the duration of analgesia. There is no significant difference in the onset of action between the two groups. Duration of sedation was observed to be similar in group I and group II. There was no case of motor blockade in both the groups. Though the difference in the duration of analgesia between the two groups is statistically significant (p<0.001), clinically the difference is about 30mins only. Hence a lesser dose of Clonidine can be used in short surgical procedures like circumcision, so that any undesired side effects can be minimized further.