Ultrasound-Guided Continuous Bilateral Erector Spinae Plane Blocks Are Associated with Reduced Opioid Consumption and Length of Stay for Open Cardiac Surgery: A Retrospective Cohort Study

Abstract

This study tested the hypothesis that continuous bilateral erector spinae plane blocks placed preoperatively would reduce opioid consumption and improve outcomes compared with standard practice in open cardiac surgery patients. Patients who received bilateral continuous erector spinae plane blocks for primary open coronary bypass, aortic valve, or ascending aortic surgery were compared to a historical control group. Patients in the block group received a 0.5% ropivacaine bolus preoperatively followed by a 0.2% ropivacaine infusion begun postoperatively. No other changes were made to the perioperative care protocol. The primary outcome was opioid consumption. Secondary outcomes were time to extubation and length of stay. Twenty-eight patients received continuous erector spinae plane blocks and fifty patients served as historic controls. Patients who received blocks consumed less opioids, expressed as oral morphine equivalents, both intraoperatively (34 ± 17 vs. 224 ± 125 mg) and during their hospitalization (224 ± 108 vs. 461 ± 185 mg). Patients who received blocks had shorter times to extubation (126 ± 87 vs. 257 ± 188 min) and lengths of stay in the intensive care unit (35 ± 17 vs. 58 ± 42 h) and hospital (5.6 ± 1.6 vs. 7.7 ± 4.6 days). Continuous erector spinae plane blocks placed prior to open cardiac surgical procedures reduced opioid consumption, time to extubation, and length of stay compared to a standard perioperative pathway.

Keywords: acute pain; cardiac surgery; erector spinae plane block; fascial plane block; morphine consumption; regional anesthesia.

Conflict of interest statement

Brian Vaughan has consulted for GE Ultrasound in the past and has an ongoing consulting relationship with Avanos Medical, teaching regional anesthesia and acute pain management to anesthesiologists. Payments for consulting are based on hourly rates and not related to the use of products or outcomes of studies. There was no involvement in the study from either company, either financial or otherwise, and Christ Hospital received no compensation, either monetary or in kind. All other authors have no competing interests. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

Figures

Figure 1

(A) Ultrasound anatomy of the erector spinae plane (ESP) prior to block placement. (B) Ultrasound demonstrating local anesthetic (LA) spread in the ESP. Abbreviations: ESM, erector spinae muscle; PL, pleura; PVS, paravertebral space; TP, transverse process.

Figure 2

Total opioid consumption during hospitalization through postoperative day 5 per case in mg oral morphine equivalents (OME) over time.

Figure 3

Box and whisker plots represent data as median values (bold horizontal line), interquartile range (box), interquartile range × 1.5 or furthest datum (dotted lines), and any outliers (open circles). Mean values are represented by blue diamonds.