A comparative study of ultrasound assisted versus landmark technique for combined spinal-epidural anaesthesia in patients undergoing lower limb orthopaedic surgery

BACKGROUND AND AIMS: Spinal anatomy is better visualised in the para sagittal oblique view with the aid of ultrasonography. The present study was undertaken to investigate whether preprocedural ultrasonography can facilitate the ease of establishing combined spinal epidural (CSE) via paramedian approach versus landmark approach in patients undergoing lower limb orthopaedic surgery. METHODS: This prospective randomised study was conducted in 100 American Society of Anesthesiologists (ASA) grade I-II patients, aged 18-60 years requiring CSE and randomly divided into two groups: Ultrasound-assisted (USG) group (n = 50) and Surface landmark (SLG) group (n = 50). The primary outcome was to compare the first pass needle success rate to establish CSE and the secondary outcomes were to compare the number of needle puncture attempts, time to establish landmarks (t1), time to accomplish CSE (t2) and complications. RESULTS: First pass needle success rate in USG group was 43 (86.0%) versus 36 (60.0%) in SLG group (P = 0.001). Number of attempts taken to establish CSE was lower in USG group as compared to SLG group (P = 0.023). t1 was greater in USG group (1.45 ± 0.47) minutes as compared to (0.79 ± 0.34) minutes in SLG group (P = 0.003). t2 was reduced in USG group (1.47 ± 0.55) minutes versus (2.73 ± 1.36) minutes in SLG group (P = 0.005). CONCLUSION: Preprocedural USG for CSE via paramedian approach increases first pass needle success rate and reduces needle puncture attempts in patients undergoing lower limb orthopaedic surgery.