Comparison of the ultra-sound-guided peri-capsular nerve group block (Peng block) and the Peng block with the lateral femoral cutaneous nerve block (LFCN) for the fractured hip surgeries – an aprospective, double-blinded randomised study

BACKGROUND AND AIMS: We hypothesised that blocking the lateral femoral cutaneous nerve (LFCN) separately may provide an additional advantage to the peri-capsular nerve group (PENG) block in terms of duration of analgesia and patient comfort. Therefore, we conducted a prospective, double-blinded, randomised study comparing the effect of PENG with that of the PENG Plus LFCN block on the duration of analgesia in fractured hip surgery. Rest and Dynamic pain scores for 24 hours were recoded as primary objectives. The duration of analgesia, the time of administration of the block until numerical rating scale (NRS) ≥ 4, the ease of spinal positioning, and side effects were recorded as secondary outcomes. METHODS: A total of 124 patients of age group 18 to 80 years, American Society of Anesthesiologists grade 1–3, were randomised into two groups. The ultra-sound-guided PENG block with ropivacaine 0.5% 30 ml and dexamethasone 8 mg was given in group A and ropivacaine 0.5% 25 ml and 5 ml at LFCN separately was given in group B. The NRS after 20 minutes, 25 minutes, and 30 minutes was noted. The ease of spinal positioning was also noted. The NRS at 4, 6, 8, 12, and 24 hours was noted in resting and movement. Any side effects were documented and treated as a hospital protocol. All patients were given a combined spinal epidural with injection bupivacaine 0.5 per cent 1.6 ml with fentanyl 20 µg. Injection paracetamol 1 gram was added 8 hourly in both the groups as a part of multi-modal analgesia. Injection tramadol 25 mg was given if NRS exceeded 4 through a patient-controlled analgesia only bolus dose, a lock-out of 10 minutes, 4 hourly, limit 100 mg, as rescue analgesia. RESULTS: NRS at rest and movement in group A (PENG) mean [inter-quartile range (IQR)] = 3 (3-2), group B (PENG+LFCN) 2 (2-1), respectively. Time to first analgesic request mean (IQR) group A 9.04 (12.5-0), group B 12.12 (14-0), ease of spinal positioning group A 3 (3-2), group B 3 (3-2). CONCLUSION: The PENG block is an effective block for fractured hip surgeries in providing ease of spinal positioning and post-operative analgesia, and if PENG is combined with the LFCN block, the post-operative analgesia is enhanced by increasing the duration and reduction in the pain score.