# Concomitant Liver Biopsy During Bariatric Surgery: No Increase in Major Complications or Readmissions but Associated with Higher Transfusion Requirements - An Analysis of the MBSAQIP Database

## TL;DR

Adding a liver biopsy during bariatric surgery does not raise major complications or readmissions but increases the need for blood transfusions.

## Contribution

This study provides the first comprehensive national analysis on the safety of concomitant liver biopsy during bariatric surgery.

## Key findings

- Liver biopsy during bariatric surgery is not independently linked to higher major complications or readmissions.
- Biopsy is associated with increased postoperative bleeding and transfusion requirements.
- Mortality remains unaffected by the addition of liver biopsy.

## Abstract

Concomitant liver biopsy during bariatric surgery has gained interest for diagnostic and research purposes, particularly in studying obesity-related liver disease. However, comprehensive data on safety remains limited using recent national databases.

A retrospective analysis of the MBSAQIP database from 2020 to 2022 was conducted. Patients undergoing primary Roux-en-Y gastric bypass or sleeve gastrectomy with or without concomitant liver biopsy were included. Primary outcomes were 30-day major complications (Clavien-Dindo grade III and IV) and mortality. Separate multivariable analyses were performed for bleeding-related complications including postoperative bleeding, transfusion requirements, and reoperation. Multivariable logistic regression analysis determined if concomitant liver biopsy independently predicted adverse outcomes.

Of 511,981 patients, 30,819 (6.02%) underwent concomitant liver biopsy. Biopsy patients had higher rates of diabetes (28.25% vs 22.65%, p < 0.001) and hyperlipidemia (25.20% vs 22.14%, p < 0.001). Mean operative time was longer in the biopsy group (96.10 vs 83.59 min, p < 0.001). Unadjusted analysis showed higher rates of major complications (Clavien-Dindo grade III and IV) (3.15% vs 2.70%, p < 0.001) and 30-day readmission (3.32% vs 2.86%, p < 0.001) in the biopsy group. However, on multivariable analysis, concomitant liver biopsy was not independently predictive of major complications (OR 0.91, 95%CI 0.79–1.04, p = 0.164) or 30-day readmission (OR 1.06, 95%CI 0.94–1.21, p = 0.344). Separate multivariable analyses for bleeding-related complications revealed that concomitant liver biopsy was independently associated with increased postoperative bleeding (OR 1.203, 95%CI 1.018–1.422, p = 0.030) and transfusion requirements (OR 1.171, 95%CI 1.028–1.334, p = 0.018), but not with reoperation (OR 1.016, 95%CI 0.908–1.138, p = 0.783).

After adjusting for patient factors, concomitant liver biopsy during bariatric surgery does not independently increase the risk of major complications (Clavien-Dindo grade III and IV), readmission, or mortality. However, it is associated with increased bleeding and transfusion complications. These findings support that liver biopsy can be performed during bariatric surgery, though clinicians should be prepared for increased bleeding-related risks and blood product utilization.