No abstract

In a randomised, single-blinded, placebo-controlled study, 27

To my knowledge the single segment combined subarachnaid epidural (CSE) block has noi been reported for Cesarean section previously. The mod~ficatlon recommended by N&kalls and Dennison whereby the spinal needle is clamped to maintain its position in the dura appears interesling. CSE block avoids one of the ms)or disadvantages of suharachnoid block in the pregnant patient, i.e., the difficulty in controlling the upper level of analgesia lf Dr, Dennison can consistently achieve a T2-Ta block with 1.5-1.6 ml isobaric subaracbnaid bupivocaine and keep the incidence of hypotenslon down to an impressive 10-15 per cent it is arguable i fan epidural catheter is necessar3 at all. In contrast to Dr. Dennison's techniqae, our aim with the CSE technique is to achieve a Ts subarachnoid block followed by extension of the block to To by injecting bupivacaine in the epidural catheter. The less extensive subarachnoid block combinad with the slower onset of epiduraf block allows more time for compensatory mechanisms to be effective and thereby minimizes the risk of precip#ous hypotension with the two stage CSE technique. We do not use prophylactic vasopressors since these drags may have undesirable fetal and maternal effects. J Thus the differences in the spread of subarachnoid blocks in spite of similar doses is due to differences in the techniques. Dr. Dennison's patients received isobaric bupivacaine while our patients were given hyperbaric buplvctcaine in the sitting posiaon. For the surgical procedure Dr. Dennison apparently i~sea the conventional subarachaoid technique while we use the CSE technique.