Capillary refill time
Capillary refill time (CRT) is used to monitor blood flow and perfusion. Tigers will need to be sedated unless they are small cubs. Pressure should be applied to the gum with a finger, and the pressure then released. The area that had the pressure applied will turn white. The time taken for the area to return to its normal colour should be recorded.
A CRT of l-2 seconds is considered normal. An increased CRT of over 2 seconds may indicate systolic failure, shock, dehydration or hypovolaemia. A decreased CRT of less than 1 second may indicate pain, septic shock or fever.
