Recombinant tissue plasminogen activator (rTPA) has become the standard thrombolytic agent for acute MI or pulmonary embolism in many centers due to its superior specificity and safety profile. A number of experimental studies and clinical reports address the use of rTPA in microvascular surgery, but most of these are case studies or small clinical series. No consensus exists regarding the indications, dose, efficacy, or safety of rTPA use. The purpose of this study was to review the experience at one institution with rTPA in the salvage of free flaps and to propose a rational algorithm for its use.
The records of all patients undergoing free tissue transfer at the University of Kentucky between April 2000 and April 2005 were reviewed. Two hundred seventy-five free flaps were performed in 259 patients, including 57 free TRAM flaps, 133 other muscle or musculocutaneous flaps, 52 fasciocutaneous flaps, 33 bone or osteocutaneous flaps, and 1 omental flap. There were 159 males and 116 females, with ages ranging from 2 to 81 years (mean: 43 years). In 27 cases (10%), the patient was brought back to the operating room in the early postoperative period (within 72 hr) for impending free flap failure. In 22 cases, thrombosis of the vascular pedicle was observed on exploration.
Treatment consisted of mechanical thrombectomy alone in 7 cases. In 15 cases, mechanical thrombectomy was combined with isolated flap perfusion with 2.5 mg of rTPA. If no effect was observed following the first dose, a second dose was administered (8 of 15 cases). In the rTPA group, 10/15 flaps (67%) were successfully salvaged. In the no-rTPA group, 2/7 flaps (29%) were salvaged. Age, preoperative risk factors, type and location of flap, and timing of reexploration were not significantly different between the two groups. Intravenous heparin was administered to 12 of the 22 patients on reexploration. There was no difference in flap survival between those who did and did not receive heparin. Three patients required a return to the operating room for a bleeding complication, one in the no-rTPA group and two in the rTPA group. All three had received intravenous heparin.
The findings suggest that the isolated perfusion of rTPA in the salvage of the failing free flap is more effective than mechanical thrombectomy alone. Intravenous heparin was not shown to improve the salvage rate in this series. Isolated perfusion with rTPA should be considered when vascular thrombosis is encountered on reexploration of the failing free flap.
