Analgesic Effects of Epidural Bupivacaine, Alone or in Combination with Clonidine on Pain after Cesarean Section

Lee, Seong Woo; Park, Byeoung Soon; Kim, Jeong Ho; Kang, Hoon Soo

Abstract

Epidural clonidine produces analgesia via non-opioid mechanism and it may be used as an adju-vant to local anesthetics in obstetric analgesia. To evaluate the effects of epidural clonidine and bupivacaine for post-cesarean section analgesia, we designed a double-blind study. Sixty patients scheduled for elective cesarean section were divided into three groups. Group 1 (n=20) received 0.125% bupivacaine 2 ml/hour epidurally for 2 days. Group 2 (n=20) received 150 ug clonidine bolus, followed by 0.125% bupivacaine 2 ml/hour and clonidine 10 ug/hour for 2 days. Group 3 (n=20) received 150 ug clonidine bolus, followed by 0.125% bupivacaine 2 ml/hour and clonidine 20 ug/hour for 2 days. At the end of the cesarean section, above drug was administered epidurally. Postoperative analgesia was assessed by recording VAS(visual analogue scales) at 1, 2, 4, 8, 16, 32 and 48 postoperative hours. Sedation score, heart rate and systolic and diastolic blood pressure were also checked. The results were as follows: 1) VAS were significantly decreased in group 2 at 1~16 hours and in group 3 at 1~32 hours compared with group 1, They were decreased in group 3 compared with group 2 at 1~48 hours but no significance was seen between two groups. 2) The changes of systolic and diastolic blood pressures & sedation scores were not significantly different between any two groups. In summary, co-administration of clonidine and bupivacaine epidurally provided more profound analgesia compared with bupivacaine alone after cesarean section.