- Release the tourniquet to stop bleeding and assess the blood supply status of the flap, spray irrigation and cover with a small gauze pad impregnated with 40mg / ml papaverin, cover the flap, put the flap back in place, apply gauze and wait for 10 - 15 minutes, then rotate the flap to cover the defect, check the blood supply status of the flap, sew and close the incisions.