Analgesic efficacy of thoracic interfascial plane blocks in multiple rib fractures: A prospective, non-randomized, controlled, double-blinded study

Background: Thoracic interfascial plane blocks are increasingly used for analgesia in rib fractures; however, their comparative efficacy for different fracture patterns remains unclear. This study Aimed to compare the analgesic and respiratory outcomes of serratus anterior plane block (SAPB) and erector spinae plane block (ESPB) within the same patient cohort.Methodology: In this prospective, non-randomized, double-blinded study, 17 ASA 1-3 patients with unilateral multiple rib fractures received both SAP and ESP catheters. Initial analgesia was initiated with a SAPB using 0.25% Bupivacaine. Based on subsequent top-up efficacy, patients were categorized into five analgesic subgroups: 'SAP only', 'ESP only', 'alternating SAP & ESP', 'combined SAP+ESP', and 'systemic analgesics required'. Pain scores and respiratory parameters were assessed at predefined intervals. Duration of action, catheter days, patient satisfaction, and complications were recorded.Results: The initial SAPB provided effective analgesia and improved respiratory outcomes in 76.47% of patients across various fracture patterns, compared to 35.29% for the initial ESPB (P=0.038). Improvements in respiratory function directly correlated with the efficacy of dynamic pain relief. When effective, both catheters exhibited a similar duration of action in the same patient. All patients reported high satisfaction, with catheter-based analgesia maintained for 3 to 5 days. No complications were observed.Conclusion: Serratus anterior plane block is associated with significantly better initial pain control and enhanced respiratory outcomes than the erector spinae plane block in the management of unilateral multiple rib fractures.