Examining microcirculation improves the angiosome theory in explaining the delay phenomenon in a rabbit model

Area of Science:

• Vascular Surgery
• Microcirculation Research
• Tissue Engineering

Background:

• Understanding flap microcirculation is crucial for surgical success.
• Choke vessels play a key role in regulating blood flow distribution within flaps.
• Previous studies have indicated complex temporal changes in flap hemodynamics post-surgery.

Purpose of the Study:

• To investigate topographic and temporal changes in circulation within rabbit dorsal skin flaps.
• To identify the specific vessels acting as choke vessels and their role in blood flow regulation.
• To elucidate the mechanisms underlying microvascular adjustments following surgical delay procedures.

Main Methods:

• Utilized laser Doppler flowmetry to measure blood flow in rabbit dorsal skin flaps.
• Analyzed circulation patterns across three distinct vascular territories.
• Monitored hemodynamic changes over extended postoperative periods, including secondary flap elevation.

Main Results:

• Identified choke vessels along the dorsal median line, distinct from interconnecting vessels.
• Observed increased proximal circulation lasting 48-72 hours, correlating with choke vessel dilation.
• Noted a delayed increase in distal circulation after postoperative day 3, concurrent with hyperemia resolution.

Conclusions:

• The findings suggest choke vessels are critical regulators of flap perfusion.
• The study postulates shared mechanisms for rapid choke vessel and microvascular dilatation postoperatively.
• Surgical delay may enhance flap survival by reducing flow resistance and mitigating proximal steal effects on distal circulation.