Real-time ultrasound guidance versus fluoroscopic guidance in thoracic epidural catheter placement: a single-center, non-inferiority, randomized, active-controlled trial

Introduction Fluoroscopy can improve the success rate of thoracic epidural catheter placement (TECP). Real-time ultrasound (US)-guided TECP was recently introduced and showed a high first-pass success rate. We tested whether real-time US-guided TECP results in a non-inferior first-pass success rate compared with that of fluoroscopy-guided TECP. Methods In this single-center, non-inferiority, randomized trial, the primary outcome was the comparison of the first-pass success rate of TECP between real-time US guidance (US group) and fluoroscopic guidance (fluoroscopy group). Secondary outcomes included time to identifying epidural space, procedure time, total number of needle passes, number of skin punctures, final success, and cross-over success. Results We randomly assigned 132 patients to the allocated groups. The difference in the first-pass success rate between the groups did not exceed the non-inferiority margin of 15% (US group: 66.7% vs fluoroscopy group: 68.2%; difference −1.5%, 95% exact CI: −14.9% to 11.9%). The difference in the final success rate also did not differ between the groups (98.5% vs 100.0%; difference −1.5%, 95% exact CI: −4.0% to 1.0%). The time to identifying epidural space (45.6 (34–62) vs 59.0 (42–77) s, p=0.004) and procedure time (39.5 (28–78) vs 112.5 (93–166) s, p<0.001) were significantly shorter in the US group. Conclusions Real-time US guidance provided a non-inferior success rate and shorter time spent on preparation and procedure compared with fluoroscopic guidance in TECP. Trial registration number KCT0006521.