Table 1. Variables that may confound evaluation of tissue perfusion.

Characteristics associated with ischemia

Previous radiation treatment

Previous surgery*

Current smoking

Obesity

Diabetes

Vasculopathy

Chronic corticosteroid use

Thin mastectomy flaps

Agents that interfere with imaging techniques and visual inspection

Methylene blue

Lymphazurin blue

Agents that affect blood flow

Vasoconstrictors (e.g., epinephrine)**

*, previous incisions may affect blood flow; ICG perfusion assessment may be of particular utility for detection of perfusion across scars; **, vasopressors affect all methods of estimation of perfusion in tissue. Diminished blood flow following administration of epinephrine may indicate the need to wait ≥2 hours for accurate ICG imaging. A negative result on ICG perfusion assessment may indicate the need to wait longer for recovery of perfusion.