PURPOSE
 Most common free flap failures are secondary to venous thrombosis. Thrombolytic agents have been used successfully to manage venous thrombosis. However, severe complications may occur when applied systemically. Recombinant tissue plasminogen activator (rtPA) in the treatment of no-reflow phenomenon in microvascular surgery was first used by Stassen et al. in two replanted fingers. Recently, Tran et al. presented a case of autogenous breast reconstruction with free TRAM flap, in which the flap was compromised by venous congestion, and salvaged by using subcutaneous rtPA. The purpose of this paper is to report and discuss another case with congested DIEAP flap, which was salvaged with subcutaneous recombinant tissue plasminogen activator treatment.
CASE REPORT
A forty-five-year-old woman underwent a delayed breast reconstruction with free deep inferior epigastric perforator flap. During surgery, dissection of the flap and the recipient vessels were uneventful. The superficial inferior epigastric vein (SIEV) was also dissected for a possible venous drainage route. We used the internal mammary artery and vein as recipient vessels. Following the anastomosis, flap color turned cyanotic, although there was no sign of venous thrombosis or kinking and twisting of the vessels. Patency of the vessels were tested and found positive. The SIEV was engorged, thus we opened the vessel and observed immediate relief and return of normal flap color. In order to be on the safe side, the anastomosis was renewed three times in a row; however we always ended up with venous congestion. We thought that the cause of venous congestion was most likely due to the dominance of superficial venous system. Since the SIEV was shortened, we were unable to do an extra venous anastomosis; and we decided to utilize leech therapy in the postoperative period along with continuous heparinization and oral aspirin. Leeches were employed for 36 hours. During this period, the flap color was still cyanotic, especially at the periphery of the flap and the capillary refill was faster than 1 second in the intervals of leech therapy. The flap temperature was low (32-33ºC), but the flap was alive, Doppler signals were audible although the flap looked compromised. At this point, we decided to try to improve the microcirculation by using rtPA as described by Tran et al . We used rtPA (ACTILYSE® 50mg, Boerhringer Ingelheim, Germany), in the dose of 2 mg in 2.2 ml distilled water, and we injected subcutaneously at multiple sites in the compromised flap.
Several hours after the injection, capillary refill returned to normal levels and flap temperature progressively increased to 35-36ºC. Eventually, lateral marginal skin necrosis of 1,5 cm width and lateral fat necrosis of 3-4 cm extension settled and was debrided 2 weeks after the operation. The discoloration at the donor area ended up with a 3x3 cm full thickness necrosis of the skin. The patient was discharged from the hospital 1 week after the surgery. She has been followed for 3 months. The flap is alive with normal color and capillary refill.
DISCUSSION
Administering rtPA subcutaneously may have some beneficial effects, such as decreasing the need for additional operations, easy application, and bedside use. Although there is no study in literature comparing the efficacy of intravascular and subcutaneous administration of the rtPA, Lantieri et al. have recently demonstrated experimentally the value of topical application of recombinant tissue factor pathway inhibitor in the prevention of microvascular thrombosis. We believe that subcutaneous rtPA was responsible for salvaging this venous congested free DIEAP flap, given the return of capillary refill and the improvement of the skin color several hours later. Our experience is similar to Tran et al who used subcutaneous rtPA for free TRAM salvage. Further investigation is mandatory to explore the efficacy and the mechanism of function of subcutaneous rtPA, however it should be kept in mind that it works in venous congestive conditions.