Peripheral Nerve Blocks for Enhanced Recovery in Cardiac Surgery: A Retrospective Observational Study

Background: This retrospective observational study evaluates the effect of incorporating peripheral nerve blocks (PNBs) into an established enhanced recovery after surgery (ERAS) protocol. The PNBs used included pecto-intercostal fascial block (PIFB) and rectus sheath block, performed under ultrasound guidance with the administration of a long-acting local anesthetic, Ropivacaine. Both patient and process outcomes were assessed to determine the effect PNBs have as part of an ERAS protocol. Materials and Methods: Adult patients undergoing cardiac surgery with midline sternotomy who were expected to be extubated within 6 hours of arrival to the intensive care unit (ICU) between October 2022 and June 2023 were included. Patients were dichotomized by whether they received a PNB or not. Outcomes included opioid consumption as measured by morphine milligram equivalents (MME), ICU length of stay (LOS), postoperative mobility, and the incidence of postoperative atrial fibrillation (POAF). Results: 431 patients were included: 170 (39.4%) received a PNB, and 243 (60.6%) did not (non-PNB group). Patients who received a PNB required a significantly shorter time to achieve first ambulation as measured from bed to chair (15.2 hours PNB vs. 18.5 hours non-PNB, P = 0.037), significantly lower rates of atrial fibrillation (26.5% PNB vs. 32.9% non-PNB, P = 0.045), shorter LOS in the ICU (44.4 hours PNB vs. 49.7 hours non-PNB, P = 0.024). Conclusion: Incorporating PNBs as part of a multimodal analgesic strategy for patients undergoing cardiac surgical procedures is associated with improved patient and process outcomes. Our finding of a reduction in POAF warrants further investigation in an adequately powered randomized controlled trial.