Background. A retrospective case-control study was conducted to assess the feasibility of erector spinae plane (ESP) block as part of a multimodal enhanced recovery program for patients undergoing minimally invasive mitral valve replacement surgery. Methods. This retrospective analysis was conducted at a single center between January and August 2019. 61 patients were included; 23 received ESP and 38 did not. Erector spinae catheters (ESCs) were placed preoperatively, using a loading dose of 30 mL .5% ropivacaine, followed by an infusion of .2% ropivacaine at 10 mL/h throughout the study period. Primary outcome was 48-hour opioid consumption. Secondary outcomes included intraoperative morphine equivalents, extubation within 24 hours, reintubation, ICU length of stay and hospital length of stay and 30-day mortality. Results. Median [inter-quartile range] of the postoperative morphine milligram equivalents (MMEs) in the first 48 hours was 70[45-121] MMEs in the ESC) group, and 109[70-148] MMEs in the no ESC group (P-value = .16). No significant difference was observed in intraoperative morphine equivalents, extubation within 24 hours or ICU length of stay. The ESC group had shorter hospital length of stay (6.0 vs 7.0 days, P-value = .043). Conclusion. This study found a statistically insignificant, though potentially clinically significant reduction in postoperative opioid consumption. A reduced hospital length of stay as well as an acceptable safety profile was also observed in the ESC group. An adequately powered, prospective trial is warranted to accurately assess the potential role for ESP catheters for patients undergoing minimally invasive mitral valve surgery.
Keywords: analgesia; minimally invasive surgery; mitral valve; research; statistics.