Introduction: We would like to explore the use of indocyanine green fluoroscopy (ICGf) in our free flaps service.
Methods: All head and neck free flap patients operated by a single surgeon from August 2020 to April 2021 were investigated with on-table ICGf immediately after microanastomosis.
Each ICGf cycle involved intravenous injection of 12.5 mg of indocyanine green in 10 ml distilled water after initiating video fluoroscopy over the microanastomosis site.
Results: 26 patients were included: 20 head and neck, 2 post oncological hand reconstruction and 4 trauma related limb reconstruction.
Flap survival was 100%. The largest flap in this study was an anterolateral thigh flap measuring 33 cm X 9cm based on a single perforator.
All arterial and venous microanastomosis were sutured with 8’0/9’0 Ethilon and venous couplers respectively.
The mean age, weight and estimated Glomerular filtration rate (eGFR) were 56 years, 79 kg and 72. All patients had normal liver function profiles.
No intravenous heparin were used prior to ICGf.
Gain at 45-55% were optimal for microanastomosis assessment.
In 5 cases where we assessed flap vascularity, Gain at 75% setting were optimal.
No anaphylaxis and/or skin reaction were observed. All patients had less than 2mg/kg of ICG.
Three required one repeat cycle (1 Indo Carmin was used in error and 2 were given before video fluoroscopy were ready).
ICGf is a sensitive tool for assessment of microanastomosis as 21 out of 26 free flaps had some leakage of the agent at the anastomosis site during fluoroscopy (no revision needed).
We observed in one case where the lumen of the flap’s vein was more than 3 times the size of the arterial lumen; the fluoroscopy signals was difficult to appreciate flow within the vein.
Conclusion: In our experience, ICGf is a safe adjunct in microanastomosis assessment for free flaps.