Real-time ultrasound-guided neuraxial puncture in elderly patients: a randomized controlled trial comparing paramedian transverse and parasagittal approaches.

Background: Historically, spinal anesthesia has been performed using anatomical landmarks. This study aimed to compare the efficacy and procedural outcomes of real-time ultrasound-guided parasagittal oblique (RTU-PO) and real-time ultrasound-guided paramedian transverse (RTU-PT) approaches in elderly patients undergoing elective surgery under spinal anesthesia.

Methods: Seventy-seven elderly patients scheduled for elective surgery under spinal anesthesia were enrolled in this study. Patients were randomized to receive spinal anesthesia using either RTU-PO (38 patients) or RTU-PT (39 patients) technique. The primary measure outcome was the rate of successful dural puncture at the first attempt in both groups. The secondary outcomes included the overall success rate of spinal anesthesia, time to identify the posterior complex on ultrasound, time to perform spinal anesthesia, total procedural time, number of needle redirections and passes, number of separate skin punctures, patients' satisfaction, and incidences of complications in both groups.

Results: Baseline demographic and anatomical characteristics were not different between the two groups. The incidence of successful spinal anesthesia at first attempt was 60.5% with RTU-PO and 56.4% with RTU-PT (P=0.71). All other secondary outcomes were comparable between the two groups except for the time to identify posterior complex that was higher in the RTU-PT versus the RTU-PO group (36±18 vs. 20±11 seconds; P=0.0001).

Conclusions: In elderly patients undergoing elective surgeries under spinal anesthesia, the RTU-PO and the RTU-PT techniques are comparable in almost all aspects.