Muscle flaps' triphasic microcirculatory response to sympathectomy and denervation

Area of Science:

• Vascular Surgery
• Microcirculation Physiology
• Surgical Innovation

Background:

• The delay phenomenon enhances skin flap survival by improving microcirculation.
• Investigating denervation's impact on muscle flap microcirculation is crucial for surgical outcomes.

Purpose of the Study:

• To determine if sympathectomy and somatic denervation increase microcirculatory flow in muscle flaps.
• To assess if this denervation mimics the delay phenomenon for improved flap survival.

Main Methods:

• Utilized a rat cremaster muscle flap model with in vivo microscopy.
• Performed sympathectomy and somatic denervation on one cremaster, with the contralateral serving as control.
• Measured red blood cell velocity, vessel diameters, capillary perfusion, and leukocyte-endothelial interactions at various delay intervals.

Main Results:

• Denervation caused a transient increase in red blood cell velocity and arteriolar dilation.
• Capillary perfusion increased significantly by 2 weeks post-denervation.
• Microvessels exhibited hyperactive responses to vasoactive agents, indicating a sensitized phase.

Conclusions:

• Proximal sympathectomy with somatic denervation induces a triphasic microcirculatory response: acute hyperadrenergic, nonadrenergic vasodilation, and a sensitized phase.
• This neurovascular manipulation improves peripheral microcirculation hemodynamics.
• Minimal access denervation offers significant microcirculatory benefits for muscle flaps without compromising blood supply.