Background and Objectives. Paresthesias and unblocked segments during continuous epidural anesthesia—sometimes leading to higher doses of local anesthetics—can increase the risk of this technique. A cephalad insertion of the epidural catheter might decrease the incidence of these problems, but this has not been evaluated before in a controlled study.

Methods. In a prospective, double-blind, randomized study, we compared the incidence of paresthesias during catheter insertion and the failure rate of continuous epidural anesthesia in two groups of obstetric patients. In group 1 ( n = 52), the Tuohy needle bevel was directed cephalad during catheter insertion. In group 2 ( n = 53), it was directed caudad. The catheter was introduced 4-5 cm into the epidural space, and bupivacaine 25 mg plus fentanyl 50 μg were administered through it.

Results. Twenty percent of the patients in group 1 had paresthesias versus 40% in group 2 ( p = 0.0249; 95% confidence interval of the difference 1-40%); intensity of paresthesias was greater in group 2. Pain relief was complete in 75% and 80% of the patients in groups 1 and 2, respectively (NS); three patients in group 1 and one in group 2 had unblocked segments (NS).

Conclusions. Our results support the contention that the catheter should be directed cephalad during insertion for continuous epidural anesthesia.