ABSTRACT
Background:Spinal anaesthesia has become the method of choice for caesarean section and hyperbaric bupivacaine isthe most commonly used drug. Intrathecal fentanyl is reported to augment analgesia produced by local anaesthetics through binding with spinal opioid receptors. Clonidine has antinociceptive effect by its action on the spinal α2 receptors and intrathecal clonidine has been successfully used for postcaesarean analgesia. Objectives: To compare efficacy and side effects of fentanyl and clonidine as adjuvant to hyperbaric bupivacaine used in spinal anaesthesia for caesarean section. Methods: Ninety healthy patients of ASA physical status l & ll, aged 18-30 years, undergoing elective caesarean section under spinal anaesthesia were randomized to two equal groups. One received 25 μg fentanyl and another 45 μg clonidine, with 0.5% hyperbaric bupivacaine (2.2 ml) intrathecally in total volume of 2.8 ml made up by addition of normal saline. Heart rate, blood pressure and SpO2 were documented at regular intervals. Pain scores were recorded by visual analogue scale. Results: The duration of analgesia was 236.9 ± 19.70 min with fentanyl and 217.2 ± 20.32 min with clonidine (p < 0.001). Hypotension occurred in 19 and 37 subjects receiving fentanyl and clonidine respectively (p < 0.001). Conclusion: Clonidine is not superior to fentanyl intrathecally as hypotension is more frequent without any significant prolongation of analgesia.
ABSTRACT
Background: Clonidine, the α2 – adrenergic agonist, has a variety of different action including the ability to potentiate the effect of local anaesthetic without any significant undesirable effects. The intrathecal use of different doses of clonidine when co-administered with hyperbaric bupivacaine provides prolongation of pain free period than hyperbaric bupivacaine alone. Objectives: Our present study was targeted to find out the optimum intrathecal dose of clonidine as an adjunct to hyperbaric bupivacaine.Methods: Patients with ASA physical status I & II scheduled for elective infra umbilical surgery under spinal anaesthesia were randomly divided into four equal groups (n = 30) by a computerized randomization chart. Groups BC15, BC30, and BC45 received mixture of 10 mg hyperbaric bupivacaine plus clonidine in the doses of 15, 30, and 45 μg respectively intrathecally and the control group (Group B) received 0.5% hyperbaric bupivacaine 10 mg and normal saline as placebo. All analysis was two tailed and P value < 0.05 was considered statistically significant. Data analyzed with the help SPSS software version 16.0 for Windows, SPSS Inc. Chicago. Results: It was observed that intrathecal clonidine to hyperbaric bupivacaine dose dependently prolongs both sensory blockade of spinal anesthesia and time to request for first supplemental analgesia in post operative period. Conclusion: Because of the absence of significant adverse effects, we conclude that, within the tested dose range, 30 μg of clonidine is the preferred dose, when prolongation of spinal anesthesia is desired.