# The Impact of Silent Liver Disease on Hospital Length of Stay Following Isolated Coronary Artery Bypass Grafting Surgery

## TL;DR

This study shows that higher liver stiffness before heart surgery is linked to longer hospital stays, suggesting it could help predict recovery time.

## Contribution

The study introduces liver stiffness measurement as a novel predictor for hospital length of stay after CABG surgery.

## Key findings

- LSM ≥ 9.5 kPa was associated with lower odds of early discharge (OR: 0.22).
- The model had good discriminatory performance with an AUC of 0.76.
- Higher liver stiffness ruled out short stays in nearly 80% of patients.

## Abstract

Objectives: Risk assessment models for cardiac surgery do not distinguish between degrees of liver dysfunction. We have previously shown that preoperative liver stiffness is associated with hospital length of stay following cardiac surgery. The authors hypothesized that a liver stiffness measurement (LSM) ≥ 9.5 kPa would rule out a short hospital length of stay (LOS < 6 days) following isolated coronary artery bypass grafting (CABG) surgery. Methods: A prospective observational study of one hundred sixty-four adult patients undergoing non-emergent isolated CABG surgery at a single university hospital center. Preoperative liver stiffness measured by ultrasound elastography was obtained for each participant. Multivariate logistic regression models were used to assess the adjusted relationship between LSM and a short hospital stay. Results: We performed multivariate logistic regression models using short hospital LOS (<6 days) as the dependent variable. Independent variables included LSM (<9.5 kPa, ≥9.5 kPa), age, sex, STS predicted morbidity and mortality, and baseline hemoglobin. After adjusting for included variables, LSM ≥ 9.5 kPa was associated with lower odds of early discharge as compared to LSM < 9.5 kPa (OR: 0.22, 95% CI: 0.06–0.84, p = 0.03). The ROC curve and resulting AUC of 0.76 (95% CI: 0.68–0.83) suggest the final multivariate model provides good discriminatory performance when predicting early discharge. Conclusions: A preoperative LSM ≥ 9.5 kPa ruled out a short length of stay in nearly 80% of patients when compared to patients with a LSM < 9.5 kPa. Preoperative liver stiffness may be a useful metric to incorporate into preoperative risk stratification.