Capillary Refill Time CRT

A capillary refill test indicates the refill of the small capillaries. Press on the gums and count until the gums return to pink. It should be 2 seconds.

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Your dog’s gums are an indicator of how well oxygen is carried to the body cells. A capillary refill test will indicate how well the body is able to refill the small capillaries. Check the capillary refill time lifting the upper lip.  Press on the gums with your finger, you will see the gum turn white. Remove your finger and count the time until the gums return to pink. In a healthy dog this should be about 1.5 seconds. A prolonged capillary refill time occurs when the blood is not flowing adequately.

Blue gums indicate the dog does not have enough oxygen going to the body. White gums indicate anemia, a lower than normal number of red blood cells. When gums are purplish gray and are combined with a slow capillary refill your dog may be in shock. Very red gums can be a response to hot weather and exercise but can also indicate an infection or toxic exposure.

If your dog is like mine, he has black pigment in his gums. Don’t panic! This can make the CRT test more difficult to do. You can check the color of the lower eyelid as a good substitute, though you can’t perform the capillary refill test on the eye.

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