The nail blanch test, also called the capillary nail refill test, is performed on the nail beds as an indicator of tissue perfusion (the amount of blood flow to tissue) and dehydration.
Review Date 4/24/2021
Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.