A clinical comparison between needle-through-needle and double-segment techniques for combined spinal and epidural anesthesia

Background and Objectives. The goal of the present investigation was to compare the double-segment and the needle-through-needle techniques for combined spinal and epidural anesthesia (CSE) in a prospective, randomized, blinded study. Methods. With Ethical Committee approval and patient's consent, 120 patients were randomized to receive CSE by the needle-through-needle (SST; n = 60) or the double-segment technique (DST; n = 60). A blind observer measured the time required from skin disinfection to readiness for surgery (loss of pinprick sensation up to T10), failure of dural puncture, need for epidural top-up before surgery, patient acceptance, and occurrence of complications. Results. No neurologic complications were observed in either group. Time to readiness for surgery was 22.7 ± 8.2 minutes in the SST group and 29.8 ± 8.31 minutes in the DST one (P < .001). Dural puncture was unsuccessful in three patients in the SST group (5%) and in one patient in the DST group (1.6%) (ns); inadequate spread of spinal anesthesia was observed in five patients in the SST group (8.3%) and in eight patients in the DST group (13.3%) (ns). No difference in the incidence of hypotension, postdural puncture headache, and back pain was observed between the two groups. Acceptance of anesthetic procedure was better in the SST (85%) than in the DST group (66.6%) (P < .05). Conclusions. The needle-through-needle technique for CSE requires less time, has no greater failure rate, and results in greater patient satisfaction than the double-segment technique. The use of a spinal needle with an adjustable locking mechanism and protruding up to 15 mm beyond the Tuohy needle improved successful spinal block in the needle-through-needle technique compared with previous reports.