Initially described in 1989, the fascia iliaca compartment block (FICB) is an unique and alternative approach to anesthetizing the femoral, LFCN, and obturator nerves for surgical procedures on the hip, thigh, and knee. This is accomplished by depositing local anesthetic into the iliac fossa where these three nerves run together. Conventionally, this block has been performed by entering the skin about 0.5 cm distal to the inguinal ligament; however, Stevens et al described a more proximal approach involving needle insertion above the level of the inguinal ligament. This study aims to ascertain any analgesic benefit conferred by the modified, or supra-inguinal, fascia iliaca (SIFI) block versus a more traditional femoral block.
IRB approval number 2017.270.C. This was a retrospective analysis of two cohorts of patients at our institution. The first cohort received a more traditional femoral peripheral nerve block, while the second cohort reviewed had been administered a SIFI peripheral nerve block. Femoral nerve blocks consisted of a single injection of equal amounts of local anesthetic, while SIFI peripheral nerve blocks consisted of an initial injection of equal amounts of local anesthetic, followed by placement of a peripheral nerve catheter that was infused with local anesthetic following completion of surgery. Post-operative opioid consumption was then evaluated at specific time intervals following admission to the post-anesthesia recovery unit.
A total of 115 patients were included in our retrospective analysis. Total post-operative opioid consumption for each patient was tabulated and then converted into standardized oral morphine equivalents. At time intervals of 8-16 hours and 24-48 hours post-operatively, there was a statistically significant decrease in the amount of opioid required for the cohort that received the SIFI peripheral nerve catheter. There was also decreased opioid usage for the SIFI cohort at the 16-24 hour interval, as well as decreased post-operative requirement for an anti-emetic that did not reach statistical significance.
DISCUSSION AND CONCLUSIONS
With our aging population, studies estimate approximately 300,000 patients yearly have fragility-associated hip fractures and this number is increasing. This care represents a large financial and resource burden to the medical system. Fragility hip fractures typically occur in elderly patients with multiple comorbidities, putting them at risk for postoperative delirium and other postoperative complications. A recent Cochran systematic review demonstrated that preoperative peripheral nerve blocks were associated with a reduction in pain, pneumonia risk, time until mobilization, and cost. Other studies have demonstrated reduction in opioid consumption, reduced need for opioid antagonist treatment, reduction in postoperative delirium, shorter hospital stay, and improved postoperative pain score when a peripheral nerve block is used in combination with routine anesthesia care. Our study suggests that there is a potential benefit with respect to opioid consumption and, presumably, associated opioid-related side effects from performing a SIFI peripheral nerve block when compared to a more conventional femoral nerve block.
At our institution, the adoption of this novel peripheral nerve block has allowed us to serve out patients better by placing perineural catheters for surgeries that were previously not amenable to them due to the proximity of the site of femoral nerve blocks to the operative field. The success of these blocks has allowed the team to implement them into a broader hip fracture pathway that aims to streamline patient care, making it safer and more efficient.