The Palmar Arch Test (PAT) is a specialty test performed to evaluate the patency of the Palmar arch in the hand prior to radial or ulnar artery harvesting in artery bypass procedures or before the surgical creation of an upper extremity hemodialysis fistula or graft.
Typically, 2 PPG sensors (photo-plethysmograph) are placed on the two extreme digits (digit 1 and digit 5). The FALCON/Pro allows placing even 5 PPG sensors on all five digits. The Palmar Arch Test protocol begins by measuring the resting PPG waveforms, then measuring the waveforms after selected compressions (compression of the radial artery, ulnar artery, or both) and finally measuring the waveforms after the release of the selected compression.
Compression is typically performed by manually compressing the selected artery or arteries. This procedure allows the examiner to evaluate whether the compression results in impeded or loss of blood flow to parts of the hand. Thus, significant reduction or loss of blood flow to areas of the hand suggests that removing that particular artery may jeopardize hand performance if the artery is removed. Clear markers in the waveforms indicate when artery compression begins, and when the compression is released.
Above is an example of a Palmar Arch Test specialty test performed
on a patient using Viasonix FALCON/Pro. First Radial artery was compressed
on two extreme digits and then Ulnar artery was compressed on the same digits.