Abstract

Combined Spinal Epidural Anaesthesia (CSEA) combines advantages of both component techniques while precluding their known disadvantages. Further, a low dose intrathecal Bupivacaine followed by sequential epidural doses calculated as per the unblocked number of segments may provide sufficient volume extension to precisely and adequately target the required surgical field. 66 patients scheduled for major surgeries under neuraxial anaesthesia were randomized into two groups. GROUP A (n=33) received CSEA with 1.5 ml 0.5% Hyperbaric Bupivacaine (7.5 mg) intrathecally at L3-L4 site followed by 0.75 ml (16 patients) to 1.5 ml (17 patients) 0.5% plain Bupivacaine per unblocked segments through epidural catheter. GROUP B (n=33) received only 2.5 ml 0.5% Hyperbaric Bupivacaine (12.5 mg) intrathecally at L3-L4 site. The maximun level of sensory block was T11 after spinal component of CSEA in group A and T6 in group B. In group a, subsequent epidural dosing of 0.5% Bupivacaine with 1.5 ml per unblocked segments (stat/increment) in 17 patients raised the level by 6-segments. In the other subgroup of 16 patients who received 0.75 ml per segment epidural dose, there was 4-segment raise in block level. Time for 2-segment regression was 0.6±0.2 hours (Group A) compared to 2.4±0.5 hours (Group B) with p<0.001. The total duration of sensory block was 1.9±0.4 hours (Group A) and 4.8 ± 1 hours (Group B) with p< 0.001. For CSEA in major abdominal surgeries, an intrathecal dose of 1.5 ml 0.5% Hyperbaric Bupivacaine (7.5 mg) is sufficient as initialising dose. The surgical need of analgesia for uncovered segments can be provided predictably with epidural 0.5% plain Bupivacaine as increments of 0.75 ml per required segment.

Description