What is the capillary refill time?

Capillaries are tiny blood vessels that lie near the surface of the skin.  They’re easiest to see in your pet’s gums, above the teeth.  The capillaries are what give the tissue its normal pink color.  You can judge the condition of your pet’s blood circulation by performing a capillary refill test.  Here’s how you do that:

  • Lift your pet’s upper lip, then press the flat of your finger against the non-pigmented, pink gum tissue.  This temporarily squeezes blood in the spot out of the capillaries and blocks the normal flow.
  • Quickly remove the pressure and you’ll see a white, finger-shaped mark on the gum.  Use the second hand on your watch to time how long it takes for the pink color to flood back into the white spot, that’s the capillary refill time.

Capillary Refill Test

Capillary Refill Time What it Means Call the Vet?
1 – 2 Seconds Normal NO
2 – 4 Seconds Moderate to poor; possible dehydration or shock YES
More then 4 seconds Emergency!  Sever problems; dehydration, shock YES, immediately
Less than 1 Emergency! Severe problems; heatstroke, shock YES, immediately

Shojai, Amy D. The First Aid Companion For Dogs & Cats. Rodale, Inc., 2001.