A pilot randomized-controlled trial evaluating the erector spinae plane block in thoracic and breast surgery

Purpose: This pilot study evaluated the feasibility of investigating the effect of the erector spinae plane (ESP) block on the patient-centred outcomes of quality of recovery-15 (QoR-15), and brief pain inventory (BPI) in thoracic and breast surgery patients. Methods: In this randomized-controlled pilot trial, 82 patients undergoing video-assisted thoracoscopic surgery (n = 77) and mastectomy (n = 5) received either continuous ESP block with ropivacaine (ropivacaine group) or the same procedure with 0.9% saline (saline group). All patients received surgical intercostal block (thoracic surgery) or local anesthetic infiltration (breast surgery). Feasibility as the primary outcome was evaluated on recruitment (three patients per week), catheter retention (above 90% at 24 hr), and patient attrition (less than 10%). Secondary outcomes comprised of QoR-15, BPI, and opioid consumption. Results: Recruitment rate was 1.8 patients per week. Catheters were retained in 77 patients (94%) at 24 hr. At three months, five patients were lost to follow-up (6%). At 24 hr compared with baseline, the ropivacaine group had a smaller decline in QoR-15 score (median difference, 14; 95% confidence interval [CI], 2 to 26; P = 0.02) and a smaller increase in BPI global score (median difference, 14; 95% CI, 0 to 24; P = 0.048). There was no difference in opioid consumption (P = 0.08). Conclusions: In this pilot study, the target recruitment rate was not met, but catheter retention and patient attrition rates were both satisfactory. A definitive trial with QoR-15 as the primary outcome would require 300 study participants. Trial registration: Australian New Zealand Clinical Trials Registry (ID12618000701224); registered 30 April 2018.