Journal of Clinical Anesthesia and Pain Management

Acute Post-Operative Outcomes of Coronary Artery Bypass Grafting with Regional Anesthesia

Introduction

Coronary artery bypass grafting (CABG) is a widely performed surgical procedure traditionally under general anesthesia; however, regional anesthesia techniques including truncal plane blocks are increasingly used. These techniques can improve post-operative pain control, reduce opioid use with better immediate post-operative pain relief and potentially reduce post-operative complications [1-3]. Regional anesthesia has been associated with improved early outcomes, including reduced postoperative arrhythmias and enhanced recovery quality [4,5]. Recommendations from the Enhanced Recovery after Cardiac Surgery Society have spurred interest in improving post-operative outcomes [6]. We sought to use a national administrative database to assess the impact of combining general anesthesia with regional anesthesia on post-operative outcomes in CABG patients. We hypothesized that the use of regional anesthesia in addition to general anesthesia would result in better hospital outcomes compared to general anesthesia alone.

The Vizient Clinical Data Base is a healthcare performance improvement analytics platform used by numerous health systems and community hospitals across the United States, including many academic medical centers. It provides comparative benchmarks such as demographics, mortality, length of stay (LOS), complication rates, readmission rates, and resource utilization. The institutional review board at the University of Arizona waived the requirement for informed consent for this retrospective review of de-identified data from the Vizient Clinical Data Base.

We performed a retrospective review of the Vizient Clinical Data Base from10/2019 through 12/2023 for all admissions aged 18 to 99-years-old with ICD-10 procedures codes for CABG. Admissions were stratified into two groups: those with an ICD procedure code for regional anesthesia (3E0T3BZ) and those without. Data collected included demographics, length of stay, overall complication rate and specific complications, comorbidities present on admission, in-hospital mortality and costs. Comparisons were made using χ ² test for categorical data, t-test for normally distributed data and Mann-Whitney U test for non-normally distributed data. A p < 0.05 was consider statistically significant. Statistical analysis was performed using SPSS version 28 (IBM Corporation, Armonk, New York).

There were 3,646 admissions with regional block (Block) and 239,159 admissions without regional block (NO-Block). Demographics and hospital outcomes are in Table 1. The Block group were younger, had a higher prevalence of Black patients and a higher complication rate, with no other demographic, outcome or cost differences.

Comorbidities are shown in Table 2. There was a higher rate of uncomplicated hypertension in the Block group with no other differences in comorbidities.

Complications are shown in Table 3. The Block group had higher rates of aspiration pneumonia, post-operative shock and C. difficile infection. There were differences in complications between the groups.

This analysis of a large, national, administrative database identified higher complication rates after CABG with general anesthesia combined with regional blocks, despite no significant differences in demographics or pre-operative comorbidities. While this is initially a counterintuitive finding, prior research still endorses the benefits of regional anesthesia.

Many findings in the literature suggests combined regional anesthesia and general for CABG may reduce postoperative pain and improve hemodynamic stability [5,7,8]. Additionally, thoracic epidural anesthesia (TEA) has shown promising results in cardiac surgery. TEA blocks cardiac afferent and efferent sympathetic fibers, reducing stress response and enhancing perioperative cardiac stability. Studies have documented its benefits, including reduced perioperative myocardial ischemia, improved left ventricular function, and decreased postoperative pain and complications. TEA's ability to improve hemodynamic stability and reduce postoperative morbidity makes it a valuable addition to cardiac anesthesia protocols [9].

Given these potential benefits of regional anesthesia for CABG outcomes, specific aspects of the process could lead to the complications observed in the data. For instance, the technical challenges of correctly placing an epidural catheter and managing the balance of anesthetic agents can contribute to adverse outcomes. Furthermore, the use of regional anesthesia in more complex cardiac surgeries, such as those involving extensive revascularization or patients with severe comorbidities, might inherently carry higher risks. These complicated procedures include repeat CABG, combined valve and CABG surgeries, and CABG in patients with significant left ventricular dysfunction or severe pulmonary hypertension. Our query of the database did not allow us to determine the procedural details to assess this, but it will be an important question for future studies to better define the different populations undergoing CABG and their anesthetic strategies. The potential benefits of regional anesthesia, such as enhanced post-operative pain control, reduced opioid consumption and better hemodynamic stability, present a compelling case for its inclusion in CABG procedures. However, careful patient selection and meticulous perioperative management are imperative to minimize risks and maximize benefits. As the medical community continues to refine anesthetic techniques and protocols, it is vital to remain vigilant about monitoring outcomes and adjusting practices based on emerging evidence.

In conclusion, this study highlights the complex interplay between regional anesthesia and post-operative outcomes in CABG patients. It calls for a nuanced approach for integrating regional anesthesia into clinical practice, emphasizing the need for ongoing research, patient-specific considerations and a commitment to improving overall surgical care.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Acknowledgements

None.

References

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