Capillary refill time (CRT) is a measure of the time it takes for a distal capillary bed, such as those found in the fingers or toes, to regain color after pressure has been applied to cause blanching. A prolonged CRT may indicate the presence of circulatory shock.

Procedure for measuring CRT

  1. Explain the procedure to the patient and obtain informed consent.
  2. Wear appropriate PPE.
  3. Position the patient with their hand at the level of their heart (or slightly higher) This will ensure that perfusion of the arteriolar capillaries carrying oxygenated blood, rather than venous stasis, is being assessed.
  4. Apply cutaneous pressure to the fingertip for five seconds. The pressure applied should be enough to cause blanching as the blood is squeezed out of the tissue.
  5. Release the pressure.
  6. Time how long it takes for the skin to return to the same color as the surrounding tissues.
  7. Document the CRT measurement in seconds, the site where it was undertaken and any factors that may have influenced the reading.

The normal CRT is <2 seconds. A CRT of >2 seconds suggests poor peripheral perfusion and may be an early sign of shock. However, several other factors can cause a prolonged CRT, including:

  • Peripheral vascular disease
  • Hypothermia
  • Cold ambient temperature
  • Old age

An alternative site for measuring the CRT is the sternum. This site is frequently used in winter when patients may come from a cold environment, which affects the accuracy of CRT. Be aware, capillary refill is generally considered clinically significant for patients under the age of 6 ONLY due to the multitude of factors that can affect capillary refill times. Despite this, capillary refill is a helpful diagnostic tool that can aid in differential diagnoses in the field.

Page data
Type Medical skill
Keywords medical, trauma
SDG Sustainable Development Goal SDG03 Good health and well-being
Authors GSTC
Published 2021
License CC-BY-SA-4.0
Language English (en)
Impact Number of views to this page and its redirects. Updated once a month. Views by admins and bots are not counted. Multiple views during the same session are counted as one. 62
Issues Automatically detected page issues. Click on them to find out more. They may take some minutes to disappear after you fix them. No main image
Cookies help us deliver our services. By using our services, you agree to our use of cookies.