Comparison of ultrasound-guided pericapsular nerve group block and femoral nerve block for reducing pain during positioning for spinal anesthesia for hip surgery

Background and Aims: Neuraxial anesthesia, including subarachnoid block (SAB), is the preferred technique for the hip surgeries. Positioning of these patients in lateral or sitting position for spinal anesthesia can be very painful due to hip fracture. This often requires systemic opioids or pre-emptive regional techniques. There is a dearth of literature comparing efficacy of two such regional techniques: pericapsular end nerve group (PENG) block and femoral nerve block (FNB). Our study compares analgesic efficacy of PENG block and FNB to facilitate positioning for SAB in patients undergoing hip surgery. Material and Methods: We conducted a prospective randomized interventional comparative study over a period of 18 months in 60 adult patients scheduled for surgery for hip fracture under SAB. Patients were randomly assigned to receive either ultrasound (US)-guided FNB, Group F ( n = 30) or PENG block, Group P ( n = 30) for reducing pain associated with positioning for spinal anesthesia. VAS scores were assessed every 5 min for 30 min after the block. Subjective assessment of quality of positioning by an anesthetist, requirement of fentanyl, and patient satisfaction level were also assessed and compared between the groups. Results: FNB while resulted in pain relief (VAS <4) within 10 min, effective pain relief required 20 min for PENG block. The onset of pain relief was faster with FNB as significantly lower VAS scores were observed in patients in FNB group as compared to those in the PENG block group on dynamic movement of hip joint at 10 min after the block ( P = 0.023). No statistically significant difference in VAS score was observed in both PENG and FNB block group at 30 min after the block administration on dynamic movement of hip and during the positioning of patient. There was also no significant difference in the quality of positioning, fentanyl boluses, and patient satisfaction between the groups. Conclusions: USG-guided FNB and PENG block, both regional techniques provided sufficient, comparable, good quality analgesia for positioning the patient for SAB.