The pulse oximeter in free muscle flap surgery. "A microvascular surgeon's sleep aid".

An open lower tibial fracture and an associated soft tissue defect were covered with a free latissimus muscle flap and skin graft. A 1.5 x 3.5 cm skin island "buoy" supplied by a single myocutaneous perforator was left attached to the revascularized muscle flap for seven days and monitored with a pulse oximeter. Pulsatile arterial flow and O2 saturation in the revascularized free flap were accurately and reliably followed postoperatively.