Purpose: The improvement of the ischaemic tolerance of myocutaneous flaps is of clinical importance and hence the subject of numerous investigations.
Methods: In an attempt to increase the ischaemic tolerance, 20 myocutaneous flaps (rectus abdominis muscle) in pigs were elevated and perfused with various, established solutions prior to the onset of ischaemia. The flaps were elevated, utilizing the superior epigastric vessels as the pedicle. Ten flaps were flushed with the University of Wisconsin solution, five with the Euro-Collins solution and the last five with a Ringer-Lactate solution, prior to the 6h long, normothermic ischaemia. On the day of operation, the first, third, fifth, seventh and tenth postoperative day clinical examinations and thermography were performed as well as biopsies. Additionally, on the tenth postoperative day, the rate of necrosis was determined morphometrically as the average of three measurements.
Results: Ten days after surgery, the flaps pretreated with the University of Wisconsin solution displayed a vital surface area of 89%, the Euro-Collins solution 23% and the Ringer-Lactate solution 14%. Histologically, muscle tissue proved to be more susceptible to ischaemia than skin.
Conclusion: Regarding the rectus abdominis flap in a pig model, the University of Wisconsin solution proved superior in the prevention of ischaemic injury compared with the Euro-Collins solution and Ringer Lactate. In accordance with the literature, muscle tissue proved to be more susceptible to ischaemia than skin in our study.