Palmar microcirculation does not deteriorate 2 years after radial artery harvesting-implications for reconstructive free forearm flap transfer

Background The functional consequences after radial artery-based forearm flaps for hand microcirculation remain unclear. We hypothesized that palmar microcirculation is compromised after radial artery removal in arteriosclerotic patients. Materials and methods A total number of 114 patients were included undergoing elective coronary revascularization using the radial artery of the nondominant forearm with non-pathological Allen's test. Palmar microcirculatory mapping with 1596 measurements was applied 2 years after removal of the radial artery regarding capillary flow, finger tip oxygenation, as well as postcapillary venous filling pressures throughout both hands using combined noninvasive real-time laser Doppler flowmetry and spectrophotometry. Results Only 2/56 positions revealed a difference beyond a 5% threshold 25 +/- 5 months after radial artery removal. Superficial capillary blood flow decreased by 13% at the hypothenar eminence (242.0 +/- 153.6 vs 275.6 +/- 169.2, p=0.009). Deep postcapillary venous filling pressure (8 mm) was significantly increased by 9% only at the fingertip of the fifth finger (112.4 +/- 49.7 vs 103.0 +/- 25.0, p=0.033). No clinical signs of malperfusion were found after radial artery removal, and no patient was impaired in his daily palmar motor activity. Conclusions Pedicled removal of the radial artery does not compromise superficial or deep palmar capillary blood flow, finger tip oxygenation, or postcapillary venous filling pressures in a long-term perspective in arteriosclerotic patients. No clinical relevant signs of malperfusion or any deterioration of palmar motor function was encountered. The blood flow via the ulnar artery and the interosseal artery compensates palmar perfusion without microcirculatory deterioration even more than 2 years after removal of the radial artery.