Checking capillary refill time of the digits is a simple physical exam used to assess a patient’s blood flow. The exam is performed by applying blanching pressure to the distal phalanx, and observing the amount of time it takes for the digit to return to its original colour. If the digit returns to its original color within 2-3 seconds, it is indicative of normal blood flow. However, if it takes longer than 3 seconds, further workup for peripheral vascular disease (PVD) is indicated.
Toll John R, Henricson J, Anderson CD, et al Man versus machine: comparison of naked-eye estimation and quantified capillary refillEmergency Medicine Journal 2019;36:465-471