Real-time ultrasound-guided vs. anatomical landmark-guided paramedian epidural anesthesia in overweight parturients undergoing analgesic labor: a randomized controlled trial

We evaluated whether real-time ultrasound-guided epidural block is more suitable for overweight parturients undergoing analgesic labor than traditional palpation positioning. Sixty overweight at-term pregnant women (body mass index 30 kg/m(2)) with singleton pregnancy, prepared for vaginal delivery with epidural analgesia, were randomly allocated into two groups. The parturients in the anatomical landmark catheterization group received paramedian epidural anesthesia using the anatomical landmark guided technique, while real-time ultrasound-guided positioning was performed in the ultrasound-guided-catheterization group. Total procedure duration, time to identify the puncture site and perform the puncture, first attempt success rate, number of attempts, number of needle-redirections, intervertebral-space-change rate, satisfaction score, and complications were compared between the groups. Procedure duration and time to identify the puncture site were significantly shorter in the anatomical landmark catheterization group (440.1 +/- 97.2 s vs. 521.9 +/- 68.4 s, p < 0.001 and 24.9 +/- 13.6 s vs. 112.2 +/- 15.6 s, p < 0.001, respectively). There was no significant difference in the time to perform the puncture (385.3 +/- 89.7 s vs. 365.1 +/- 73.0 s, p = 0.341). The first attempt success rate was lower while the number of attempts and number of needle-redirections were higher in the anatomical landmark catheterization group (p < 0.05). The intervertebral-space-change rate was similar across the groups. Satisfaction was significantly lower in the ultrasound-guided catheterization group (p = 0.009). Complication occurrence, e.g., catheterization difficulty or bleeding during catheterization, dural puncture, and lower-back pain, was similar across the groups. Real-time ultrasound-guided paramedian epidural anesthesia improved the first attempt success rate and reduced the number of attempts and number of needle-redirections in overweight parturients undergoing analgesic labor. However, the longer total procedure duration and time to identify the puncture site might dissatisfy parturients.