A randomized clinical trial comparing different combination of peripheral nerve blocks for intraoperative analgesia in patients on antithrombotic drugs undergoing hip fracture surgery: pericapsular nerve group (PENG) block versus femoral and obturator nerve block.

Background: Locoregional anesthesia is commonly used in orthopedic trauma surgery, particularly in elderly patients. We conducted a prospective, monocentric, randomized controlled trial to evaluate the anesthetic and analgesic efficacy of pericapsular nerve group (PENG) block in patients on antithrombotic drugs undergoing hip fracture surgery, comparing it with femoral and obturator nerve block (FNB+ONB).

Methods: Forty patients were randomly allocated to receive a PENG block or FNB and ONB, both combined with wound infiltration (WI). The main outcome was pain, assessed using a Numeric Rating Scale (NRS) 30 minutes after the block, in Post Anesthesia Care Unit (PACU) and in the postoperative 6, 12 and 24 hours. Secondary outcomes included intra and postoperative analgesic requirement, need to increase the level of sedation and postoperative complications.

Results: We observed, except for 12 hours post-surgery, higher NRS values for PENG group compared to FNB + ONB group, with a median (IQR) NRS of 3 (2-4) vs. 2 (1-3.25) 30 minutes after the block, 1.5 (0-3.25) vs. 0 (0-1.25) at PACU, 1.5 (0-2) vs. 1 (0-2.25) at 6 hours, 1.5 (0-2) vs. 2 (1-2) at 12 hours, and 2 (0-2) vs. 1.5 (0-2) at 24 hours. Despite this, no result was statistically significant; all P>0.05. No differences were observed as regards other secondary outcomes.

Conclusions: Our results suggest that PENG block is not inferior to FNB + ONB as anesthetic and analgesic technique in patients on antithrombotic drugs undergoing hip fracture surgery.