Utility of a Smartphone Application in Assessing Palmar Circulation Prior to Radial Artery Harvesting for Coronary Artery Bypass Grafting

Coronary artery bypass graft (CABG) surgery is a procedure where surgeons use blood vessels from elsewhere in the body to go around blockages or narrowings in the heart arteries. Before the surgery, the surgeon needs to choose which vessel will be used for the bypass, including potentially the radial artery in the wrist. Before using this artery, it is important to ensure that there is enough blood flow to the hand to prevent complications. The best way to do this involves the use of ultrasound, but this takes a long time and its availability can be limited. Therefore, the assessment is usually done at the bedside by examining the hand, which relies on the doctor watching the flushing of the hand during compression and release of the artery. Currently, smartphones with cameras are able to assess blood flow by passing light through the skin and observing differences in brightness. This has been shown in a previous study to be a better way to assess the arteries in the hand than the traditional examination, as it is less subjective than simply watching the flushing of the hand. In this study, the investigators will assess the utility of a smartphone application in determining whether there is enough blood flow in the hand prior to using the radial artery for CABG surgery.