Medical Dictionary Search Engines

Please be patient! It may take up to ONE minute to load all the Engines.
Problems? Please contact our support.


Search For


Specialty Search




Other encyclopedia topics: A-Ag Ah-Ap Aq-Az B-Bk Bl-Bz C-Cg Ch-Co Cp-Cz D-Di Dj-Dz E-Ep Eq-Ez F G H-Hf Hg-Hz I-In Io-Iz J K L-Ln Lo-Lz M-Mf Mg-Mz N O P-Pl Pm-Pz Q R S-Sh Si-Sp Sq-Sz T-Tn To-Tz U V W X Y Z 0-9   

Capillary nail refill test

Alternative names

Nail blanch test; Capillary refill time; CRT


This quick test is performed on the nail beds o monitor tissue perfusion (the amount of blood flow to tissue) and dehydration .

How the test is performed

Pressure is applied to the nail bed until it turns white, indicating that the blood has been forced from the tissue (blanched). Once the tissue has blanched, pressure is removed.

The health care provider will measure the time it takes for blood to return to the tissue, indicated by a pink color returning to the nail.

How to prepare for the test

No preparation is necessary for the test.

How the test will feel

There will be minor pressure to the bed of your nail but it should not cause discomfort.

Why the test is performed

Oxygen, which is critical to the survival of tissue, is carried to various parts of the body by the blood (vascular) system. This test measures how well the vascular system is functioning in your extremities. If you are dehydrated, or tissue perfusion is blocked by other means, this quick test can alert you or your health care provider that care needs to be taken to restore normal vascular flow.

Normal Values

If there is good perfusion to the nail bed, a pink color should return in less than 2 seconds after blanching.

What abnormal results mean

Blanch times that are greater than 2 seconds may indicate:
  • dehydration
  • shock
  • peripheral vascular disease ( PVD )
  • hypothermia

What the risks are

No risks are associated with this test.

Update Date: 8/18/2003

Daniel Levy, M.D., Ph.D., Infectious Diseases, Greater Baltimore Medical Center, Baltimore, MD. Review provided by VeriMed Healthcare Network.

©2009 [Privacy Policy] [Disclaimer]
Last updated: Tue, 06 Jan 2009 00:20:03 GMT