D25-11 Variation in Thoracic Nerve Block Use for Coronary Artery Bypass Grafting (CABG) and Associations With Postoperative Pain Outcomes

Rationale Thoracic nerve blocks are utilized in coronary artery bypass grafting (CABG) to provide regional anesthesia during and after surgery, with the aim of reducing postoperative pain and opioid requirements. Despite their potential benefits, multicenter data describing their utilization patterns, patient selection, and associations with pain-related outcomes remain limited. Methods We conducted a retrospective cohort study using the Premier Healthcare Database (Q4 2022-Q3 2024) including adult inpatient encounters for CABG (by International Classification of Diseases [ICD], 10th Revision and Current Procedural Terminology [CPT]) admitted to hospitals that use both anesthesia charge codes for CABG and either CPT or charge codes to capture nerve blocks. Patients were excluded for concomitant endocarditis, valve replacement, aortic dissection, or mechanical circulatory support. Multilevel multivariable logistic regression models with hospital and surgeon random effects were used to assess variation in thoracic nerve block use. Associations between nerve block use and postoperative outcomes (primarily, days without opioids through post-operative day 7) were estimated using hierarchical multivariable regression models. Results Among 7,221 eligible CABG encounters (median [interquartile range, IQR] age: 68 [62, 74] years; 78.2% male; 1.2% in-hospital mortality) across 42 hospitals and 89 surgeons, nerve block use varied by site (median [IQR] {full range}: 0% [0%, 2.2%] {0%, 70.6%}) and surgeon (0% [0%, 0%] {0%, 85.7%}), with 29 (69.0%) hospitals and 76 (85.4%) surgeons never using a nerve block. The adjusted median odds ratio demonstrated substantial variability at the hospital (model including all hospitals, median odds-ratio [95% confidence interval]: 1745.25 [343.23, 10820.11; model excluding hospitals with no nerve block use: 5.74 [4.25, 8.14]) and surgeon (7241.47 [2274.02, 24909.15]; 7.74 [5.42, 11.03]) levels, associations much larger than any seen for patient-level characteristics (e.g., non-commercial / non-Medicare insurance vs Medicare, model including all hospitals, odds-ratio [95% confidence interval]: 0.33 [0.15, 0.74]). Use of nerve blocks was not associated with fewer days of opioids through day 7 (adjusted risk ratio [95% confidence interval], model with hospital as a random effect: 0.97 [0.91, 1.03]; model with hospital and surgeon as random effects: 0.98 [0.91, 1.05]), although durations of invasive mechanical ventilation and hospital stay were shorter with nerve block use (Table). Conclusions Use of thoracic nerve blocks for CABG varies widely across hospitals and surgeons, primarily reflecting provider and institutional preference rather than patient or procedural factors. While clear evidence of better postoperative pain control was not apparent, nerve blocks may improve other meaningful clinical outcomes. This abstract is funded by: University of Miami Miller School of Medicine