# Early Postoperative Increase in Transforming Growth Factor Beta-1 Predicts Microvascular Flap Loss in Reconstructive Surgery: A Prospective Cohort Study

## TL;DR

A rise in TGF-β1 after surgery can predict microvascular flap failure, offering a new biomarker for early detection in reconstructive surgery.

## Contribution

This study identifies TGF-β1 as a novel predictor of microvascular flap complications through postoperative blood analysis.

## Key findings

- Postoperative TGF-β1 increases were significantly higher in patients with flap loss compared to those with healthy recovery or minor complications.
- TGF-β1 levels correlated with preoperative markers like C-reactive protein, fibrinogen, hematocrit, and hemoglobin.
- Monitoring TGF-β1 changes could help predict flap loss early after surgery.

## Abstract

Background and Objectives: Microvascular flap surgery is a widely used reconstructive technique for the repair of various defects. Biomarkers have become an essential tool for monitoring flap viability, early detection of complications, and prediction of surgical outcomes. Studies focusing on immunomodulatory cytokines in the early prediction of microvascular flap complications are lacking. We aimed to investigate the predictive value of postoperative changes in transforming growth factor beta-1 (TGF-β1) for microvascular flap complications. Materials and Methods: This prospective observational study comprised 44 adults scheduled for elective microvascular flap surgery. Preoperative blood samples for analysis were obtained before surgery, prior to the administration of intravenous fluids. Postoperative blood draws were collected after surgery, before leaving the operating room. Preoperative and postoperative serum concentrations of TGF-β1, as well as preoperative plasma albumin, total protein, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, full blood count, albumin, interleukin-6, C-reactive protein, and fibrinogen, were determined. Results: Postoperative changes in TGF-β1 were higher in cases with flap loss compared to patients with healthy recovery or patients with minor flap complications (0.403 log10 of ng/mL [0.024–0.782] vs. 0.157 [0.029–0.285] vs. −0.089 [−0.233–0.056], p = 0.002). Increased postoperative TGF-β1 was positively linked to preoperative C-reactive protein (p = 0.021), fibrinogen (p = 0.020), hematocrit (p = 0.039), and hemoglobin (p = 0.009). Conclusions: The postoperative increase in circulating TGF-β1 was associated with microvascular flap complications. Assessment of the postoperative changes in circulating TGF-β1 may be valuable for the early postoperative prediction of true flap loss.