Cutaneous blood flow in the TRAM flap.

Changes in the cutaneous blood flow of the pedicled TRAM flap for breast reconstruction were studied in 15 patients with laser Doppler flowmetry (LDF) and transcutaneous oxygen tension (ptcO2). One patient was excluded from the study. The LDF value increased to 127 +/- 15% of the base line on the random and to 151 +/- 13% (p less than 0.01) on the axial side after dissection of the random side of the flap. Ligation of the deep inferior epigastric artery caused a decrease to 57 +/- 8% (p less than 0.001) on the random and to 78 +/- 11% on the axial side. The random side ptcO2 decreased from 48 +/- 2 mmHg [6.4 +/- 0.3 kPa] to 17 +/- 5 mmHg [2.3 +/- 0.7 kPa] (p less than 0.001) after dissection of the flap and remained near zero for one week. Eight patients developed minor cutaneous necrosis on the random side, probably because the superior epigastric system could not adequately nourish the TRAM flap. Low LDF and ptcO2 values after pedicle ligation and a negative response to oxygen stimulation predicted skin necrosis.