Pericapsular nerve group block: an overview.

INTRODUCTION: The PENG block is a recently described ultrasound-guided technique for the blockade of the sensory nerve branches to the anterior hip joint capsule. It was described as an analgesic block for the acute pain management after hip fracture, while subsequent studies expanded the original indication. The aim of this narrative review was to summarize the existing knowledge about the PENG block from the anatomical bases and to provide an up-to-date description of the technique, applications and effects. EVIDENCE ACQUISITION: We reviewed the following medical literature databases for publications on PENG block: PubMed, Google Scholar, EMBASE, and Web of science until August 31st, 2020. Data regarding anatomy, indications, drugs and technique were also collected, reported and discussed. EVIDENCE SYNTHESIS: From our search result we selected 57 relevant publications. Among them, 36 were case reports or case series and 12 publication were letters or correspondence; no RCT was identified. The main indication is the hip-related analgesia. The most commonly injected drug is a 20ml long-acting local anesthetic. There are some cases of femoral and obturator nerve block, but no major complication such as hematoma/bleeding or needle-related organ injury has been reported yet. CONCLUSIONS: The PENG block is a promising technique. Randomized controlled trials of high methodological quality are required to further elaborate the role of this block.

Continuous PENG block for hip fracture: a case series.

INTRODUCTION: The pericapsular nerve group (PENG) block is a novel regional technique indicated for analgesia for hip joint pain. We administered PENG blocks and performed catheter insertion for continuous infusions in patients with femur fractures on hospital admission. In this case series, we describe our initial experience of pain management in 10 patients with continuous infusion and its associated adverse events. CASE SERIES: The PENG block was administered with an introducer needle. The catheter was then inserted 3 cm beyond the needle tip. In three patients, blood aspiration through the catheter occurred. In each patient, the catheter was repositioned 0.5-1.0 cm more medially. No blood aspiration or visible hematoma occurred subsequently. The presence of any vascular structure deep to the iliopsoas muscle was excluded postoperatively based on a Doppler color flow scan. DISCUSSION: Overall, eight patients had femoral neck fractures, and two patients had intertrochanteric fractures. All 10 patients reported good pain relief. The median (IQR) Numerical Rating Scale (NRS) score decreased from 7 (6-7) before the block to 2 (2-2.75) 20 min after PENG catheter placement. The median (IQR) NRS score after 12, 24 and 48 hours were 2 (2-3), 2 (2-3), and 2 (0.25-2), respectively. Patients underwent surgery 24-48 hours following catheter placement. Catheters were removed by an Acute Pain Service nurse 72 hours postinsertion. We want to highlight the potential for intravascular catheter placement in this anatomical region. Further studies are required to confirm if this is a technical error or an associated complication of continuous PENG blocks.