# Implantation of a vascular access button in mice

## TL;DR

This study evaluates the implantation of vascular access buttons in mice, showing high success rates and providing guidelines for optimal use.

## Contribution

The study introduces standardized methodologies for vascular access button implantation in mice, validated through survival, patency, and clearance analyses.

## Key findings

- VAB implantation achieved a 90.2% technical success rate and 80.4% 28-day survival rate.
- Optimal catheter insertion lengths were determined for different mouse weights.
- VAB administration showed advantages over venipuncture in biodistribution and clearance.

## Abstract

Vascular access presents unique challenges in experimental mice due to their small size and anatomical constraints. Achieving reliable vascular access is crucial for optimizing experimental outcomes, especially in protocols requiring serial blood sampling or repeated intravascular therapy. Although vascular access buttons (VABs) offer significant advantages, their widespread adoption has been limited by technical challenges and a lack of comprehensive validation regarding their safety, feasibility, and long-term management. To address these gaps, we conducted a comprehensive evaluation of VAB implantation in mice. The technical success rate was 90.2%, and the 28-day survival rate was 80.4%. Optimal catheter insertion lengths determined by intraoperative and autopsy findings, and computed tomography were 9.5 ± 0.6 mm (20–25 g), 10.1 ± 0.8 mm (25–30 g), and 11.2 ± 0.5 mm (> 30 g), respectively. Catheter patency was analyzed by stratifying the cohort into groups based on physical parameters such as catheter tip geometry, heparin concentration in the maintenance solution, and frequency of catheter maintenance procedures. Although approximately half of the mice lost complete catheter patency by day 14, the majority maintained partial patency at day 28 in all experimental groups except for two cases of complete occlusion in the 2 Fr square tip, low-dose heparin, weekly maintenance group. The evaluation of biodistribution and clearance with indocyanine green indicated that VAB administration may have advantages over conventional venipuncture. These standardized methodologies can provide a framework for diverse biomedical research applications, enhancing both the efficiency and reproducibility of studies requiring reliable vascular access.

The online version contains supplementary material available at 10.1038/s41598-025-20542-4.