Imaging technique to predict skin death during mastectomy and reconstruction surgery

Intervention: Surgery WITH Indocyanine green Angiography Materials: Laparotomy sponges and staples DRUG: Indocyanine green (ICG) supplied as a sterile water-soluble lypophilised power: Infracyanine® 25mg/10mL (SERB, Paris, France) - strength: 25mg/mL - dose: weight-dependent dosage: 2mL for patients weighing <50Kg, 3mL for patients weighing 50-100Kg, and 4mL for patients weighing over 100Kg - duration: single Stat dose - mode: intravenous injection Normal saline: 10mL flush following administration of indocyanine green Near-infrared light source from the SPY Elite System or SPY PHI (Novadaq Technologies Inc., Mississauga, Canada) Procedures, activities, and/or processes used: 1. Skin- or nipple-sparing mastectomy 2. Clinical assessment of mastectomy skin flap perfusion by surgeon and first assistant: skin tissue colour, capillary refill, turgor, temperature and dermal edge bleeding 3. Placement of laparotomy sponges in breast pocket to fill dead space and allow skin flaps to lie flat without areas of redundancy or stretch 4. Temporary closure of skin with staples 5. Indocyanine green administered intravenously stat, at a weight dependent dosage, just after completion of mastectomy and prior to reconstruction 6. Operating room lights will be turned off 7. Excitation of fluorescence by near-infrared light source from the fluorescence imaging systems: SPY Elite System or SPY PHI (Novadaq Technologies Inc., Mississauga, Canada) 8. Video recording of perfusion for a total of 90 seconds after fluorescence is first detected in mastectomy skin. Bilateral cases will be recorded for bilateral cases, recorded with a single administration of indocyanine green (ICG) dye and snapshots will be taken of both breasts within 10 seconds of the 90-second time point 9. Analysis of skin flap vascularisation using perfusion maps and perfusion values obtained by SPY-Q software at the 90-second-point 10. Assessment of perfusion as “well perfused”, “adequately perfused”, “marginal” or “poorly perfused” using absolute (based off of a fixed greyscale that is consistent from image to image) and relative perfusion values. 11. Surgical decision regarding reconstruction to be made such as proceeding with breast reconstruction, delaying breast reconstruction or excising nonviable tissue 12. Completion of reconstruction note: preoperative antibiotics and drains are used if indicated Who: Surgeon and first assistant Mode of delivery: Face to face, provided individually Number of times: Single dose administration of indocyanine green Duration: Angiography will video record perfusion for a total of 90 seconds after fluorescence is first detected in the mastectomy skin. Bilateral cases will be recorded with a single administration of indocyanine green (ICG) dye and snapshots will be taken of both breasts within 10 seconds of the 90-second time point. Location: Operating theatres Duration: Total duration of breast reconstruction is approximately 130minutes, with the intervention (indocyanine green administration, perfusion analyses and interpretation) adding approximately 10 minutes to the total surgical time Monitoring of adherence: Adherence to the intervention will be followed by the use of laminated sheets with instructions on dosage and administration of Indocyanine Green, and examples of well and poorly perfused skin flaps for reference.