Evaluating local ischemic preconditioning effects on skin perfusion using capillary refill time in healthy volunteers

Capillary refill time (CRT) is a vaso-occlusive test that allows the non-invasive assessment of skin perfusion. A vascular occlusive test (VOT) induces transient ischemia similar to that used in preconditioning ischemia. We hypothesized that CRT could be influenced by local tissue compression mimicking ischemic preconditioning when repeated measurements are performed. In healthy volunteers (n = 30), CRTs were performed twice on the index and middle fingers of the dominant hand and the index finger of the non-dominant hand at 15-minute intervals on the first day. On the second day, two CRT measurements were taken at 30-minute intervals. No significant differences were observed in CRT measurements repeated at 15- and 30-minute intervals. Additionally, baseline CRT values did not significantly differ between the fingers of the dominant and non-dominant hands on either study day. Repeated CRT measurements are not influenced by local ischemic preconditioning in the finger over short intervals.