Principles of Microvascular Reconstruction in Electrical and Burn Injuries

With the progress of microvascular free tissue transplantation in recent decades, these procedures have increasingly been used for reconstruction in burn patients and have reached a high level of sophistication. Fascial flaps, preexpanded flaps, composite tissue flaps, multiple flap transfer in the same patient, and two- or three-lobed combined flaps (“chimeric” flaps) based on a single pedicle have been used in patients with severe burns and larger defects. The purpose of this study was to provide principles for decision-making in microvascular burn reconstruction, particularly with regard to type of injury and timing for free flap coverage.

Between July, 1994 and November, 2002, a total of 75 free flaps were performed in 60 burn patients. Patient data were analyzed retrospectively for age and gender, type of injury, indication for a free tissue transfer, timing of the reconstructive procedure, as well as for the complications, final outcome, and success rate.

The average age of the 13 women and 47 men was 35 years (4 to 75 years). The etiology of the burn was a high voltage injury (n = 26) or a full-thickness burn injury (n = 49). Forty-three free flaps were used for primary reconstruction (< 6 weeks) and 32 flaps for secondary reconstruction of unstable burn scars or contractures. Twenty different types of free flaps were used. Combined flaps with at least two components based on one pedicle (chimeric) were performed in 10 cases. Overall, the flap success rate was 87%. The authors were able to show a relationship between flap failure rate (n = 10) and timing of the procedure. Eighty percent of the flap failures occurred within 5 to 21 days after trauma, and all flap failures between 5 days and 6 weeks. No flap failure occurred during secondary reconstruction.

In this large series of free flap reconstruction in burn patients, an increased risk of flap failure was demonstrated when the free flap was performed within 5 to 21 days after trauma. The reconstructive principles in primary and secondary burn reconstruction were discussed, and an algorithm for adequate treatment was presented.