Background and Aims Spinal anesthesia in obese parturients is difficult yet there are no guidelines to direct best practice. Ultrasonography (US) is considered standard care for regional anesthesia. The aim of this study was to evaluate the benefits of preprocedural US scanning to improve the first-attempt success rate in obese parturients.

Methods After agreement from the local ethics committee and informed patient consent, we conducted a prospective, randomized controlled study including parturients over the age of 18 with a body mass index ≥30 kg/m2 and scheduled for elective cesarean delivery. Participants were randomized into 2 groups: a standard palpation group (standard group) and a pre-puncture US-guided neuraxial anesthesia group (US-group). The primary outcome was first pass success rate. The secondary outcomes were the number of punctures and intervertebral interspaces attempted, needle redirection, procedure Time, incidence of complications and patient satisfaction score. For all statistical tests, the significance level was set at 0.05.

Results Until now, 71 parturients were recruited: 33 in US-group and 38 in standard group. No clinically intergroup differences were noted regarding the demographic data. The US-group had a higher first-attempt success rate: 51.5% vs 28.9% in standard group but not significant statistically (p=0.052). There were no significant differences between the groups regarding the secondary outcomes. However, more time was required to perform the procedure in US-group (P <0.001) (table1).

Conclusions Preliminary results demonstrated that preprocedural US didn’t increase the first pass success rate. We probably need a larger sample and an US scan to be performed by operators with competence in this area.