|To assess blood flow, your veterinarian may press on your pet's gums with a finger, and then release the pressure. In doing this, your veterinarian is checking your pet's 'capillary refill time.' There are many small blood vessels called capillaries in an animal's gums. When an area of the gum is pressed, blood is forced out of these capillaries. When the pressure is released, the blood should almost immediately refill the capillaries.
The normal time it takes for the capillaries to refill in the dog and cat is 1.5 seconds. A prolonged capillary refill time (CRT) occurs when the blood is not flowing adequately. This can occur if the pet is in, or is going into, shock. It can also occur in certain heart diseases. Taking the CRT is a fast and easy measurement which may indicate the pet has a serious condition.