Efficacy Of High Volume Pericapsular Nerve Group Block in Patients with Acetabular Fracture for Positioning for Subarachnoid Block: A Pilot Study

Background: Positioning the patients with acetabular fracture surgeries for neuraxial anesthesia is extremely painful and systemic opioids have limited efficacy. High volume pericapsular nerve group (PENG) block is known to provide a good analgesia for pain around hip but has not been investigated for fracture acetabulum. The aim of the present study was to evaluate the efficacy of high-volume PENG block in improving analgesia and enabling patient positioning for subarachnoid block. Methods: We conducted a prospective single group interventional pilot study in level 1 trauma center in Northern India. Patients between 18 and 75 years of age and ASA physical status of 1 or 2 were enrolled with acetabular fracture scheduled for open reduction and internal fixation (anterior approach) surgery. We assessed numerical rating scale (NRS) score for pain at supine and sitting position and the maximum sitting angle before and 30 minutes after administration of 30ml PENG block. Any need for rescue analgesia and assistance for maintaining the position were noted. Results: A total of 14 patients were recruited. There was a significant decrease in NRS score before and after intervention (supine mean NRS score before vs after block: 3.85±1.4 vs 0.5±0.85, p <0.001; sitting mean NRS score before vs after block: 7.64±1.33 vs 2.21±1.62, p <0.001) along with significant improvement in sitting angle (before vs after block: 35.35 ⁰ ±8.42 ⁰ vs 87.85º±4.25, p <0.001). Conclusions : High-volume PENG block significantly reduces pain scores and increases sitting angle during positioning for neuraxial anesthesia in patients with acetabular fracture. Study was registered on 06/10/2021 in the clinical trial registry of India (www.ctri.nic.in) with unique ID number: CTRI/2021/10/037143.