ABSTRACT
This study was designed to quantify the relative contribution of the inferior and
superior epigastric systems to infraumbilical TRAM flap skin blood flow, using laser
Doppler flowmetry. In twelve flaps (11 patients), blood-flow measurements were obtained
during routine elevation of the TRAM flap for breast reconstruction. Baseline readings
were obtained and recorded after stabilization of blood flow. The deep inferior epigastric
artery and vein (IEA) were clamped and measurements were obtained. An atraumatic aortic
clamp was then placed across the superior strip of rectus abdominis muscle, occluding
the superior epigastric system (SEA) and all collateral branches from the superior
circulation, and readings obtained. IEA occlusion produced a reduction in skin flap
blood flow which averaged 23 ± 21 percent of baseline. When the SEA system was occluded,
no significant decrease was noted. In fact, skin blood flow increased to 136 ± 69
percent of baseline. When both the SEA system and IEA were clamped, skin blood flow
averaged 10 ± 9 percent of baseline, representing random movement of erythrocytes.
The present study quantitatively documents the overwhelming dominance of the IEA system
to supply the skin of the infraumbilical TRAM flap.
