Pre-procedural ultrasound scanning for subarachnoid block versus landmark guided subarachnoid block in obese patients: A prospective randomized controlled study

Pre-procedural ultrasound scanning for subarachnoid block versus landmark guided subarachnoid block in obese patients: A prospective randomized controlled study - Background and Aim of the Study: Obese patients present unique challenges for subarachnoid block due to difficulty in identifying surface landmarks, which increases the risk of multiple attempts and complications. Pre-procedural ultrasound (US) guidance can enhance precision in identifying intervertebral spaces. This study aimed to compare the efficacy of ultrasound-guided versus landmark-guided techniques for spinal anaesthesia in obese patients. The primary objective was to compare the number of attempts required for successful subarachnoid block, while secondary objectives included comparisons of needle passes, time to identify intervertebral space, time for successful lumbar puncture, and time to achieve successful subarachnoid block. Materials and Methods: A prospective randomized controlled study was conducted on 90 obese patients (BMI 30–40 kg/m?2;) scheduled for surgery under spinal anaesthesia. Patients were randomly allocated to either Group-L (landmark-guided, n=45) or Group-P (US-guided, n=45). Data collected included the number of attempts, needle passes, time to identify intervertebral space, time for scanning, time for lumbar puncture, and time to achieve successful subarachnoid block. Result: The mean number of attempts for Group P (1.42 ± 0.62) was significantly lower than Group L (1.91 ± 0.73, p < 0>p < 0>p < 0> Conclusion: Pre-procedural ultrasound scanning significantly improves the success rate of subarachnoid block in obese patients by reducing the number of attempts, needle passes, and procedural time compared to the traditional landmark-guided technique. Keywords: Subarachnoid block, Ultrasound guidance, Obese patients.