Microcirculation Evaluated by Intraoperative Fluorescence Angiography after Tibial Bypass Surgery

Area of Science:

• Vascular Surgery
• Medical Imaging
• Circulatory Physiology

Background:

• Adequate foot microperfusion is essential for ulcer healing in critical limb ischemia.
• Tibial bypass surgery is a key intervention for limb salvage in these patients.
• Evaluating the immediate impact of surgery on microcirculation is crucial for understanding outcomes.

Purpose of the Study:

• To assess the immediate effect of tibial bypass surgery on lower limb microcirculation.
• To correlate microcirculatory changes with macrocirculatory parameters and clinical outcomes.

Main Methods:

• Prospective analysis of 33 patients with critical limb ischemia (Rutherford IV-VI) undergoing tibial bypass.
• Intraoperative fluorescence angiography using Indocyanine green to evaluate microperfusion (Ingress and Ingress Rate) before and after surgery.
• Ankle-brachial index (ABI) measured to assess macroperfusion; clinical outcomes assessed at follow-up.

Main Results:

• Significant improvement in microcirculation parameters (Ingress and Ingress Rate) post-tibial bypass surgery.
• Microcirculation parameters showed a significant positive correlation with the ankle-brachial index.
• Patients with greater postoperative improvement in microcirculation demonstrated better clinical outcomes (wound healing, absence of rest pain).

Conclusions:

• Intraoperative fluorescence angiography effectively quantifies the improvement in microcirculation after tibial bypass.
• Enhanced microcirculation post-surgery is linked to improved macroperfusion (ABI) and better clinical results.
• The degree of microcirculatory improvement predicts the likelihood of successful wound healing and pain relief.