Pengaruh Titrasi Indocyanine Green terhadap Intensitas Fluoresensi pada Perfusi Flap Bebas dalam Menunjang Tindakan Bedah Mikro Rekonstruksi: Tinjauan terhadap Suhu, TcPCO2, TcPO2, Ekspresi HIF-1α, dan Histopatologi Flap = The Effect of Indocyanine Green Titration on Fluorescence Intensity in Free Flap Perfusion to Support Reconstructive Microsurgery Procedure: A Review of Temperature, TcPCO2, TcPO2, Expression of HIF-1α, and Flap Histopathology