Hemodynamic and Geometric Factors in Flow-Through Chain-Linked Double Free Flap Reconstruction: A Critical Analysis

Abstract

Complex head and neck defects requiring double free flap reconstruction present unique challenges in vascular design. Flow-through configurations, where one flap's arterial supply feeds a second flap, offer theoretical advantages but create inherent vulnerabilities. This seminar examines the hemodynamic and geometric principles underlying flow-through reconstruction, analyzes common failure mechanisms, and provides practical guidelines for surgical decision-making. Key concepts include retrograde thrombus propagation, cumulative pressure drops in series circuits, and the non-Newtonian properties of blood that complicate theoretical predictions. Understanding these principles is essential for appropriate patient selection and technical execution in complex reconstructive cases.

Keywords

free flap - flow-through - hemodynamics - microsurgery - head and neck reconstruction

Publication History

Article published online:
18 December 2025

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