Capillary refill

In adults CRT can be measured by applying pressure to the pad of a finger or toe for 5–10 seconds. It became popularized in the 1980s when Champion et al. proposed a CRT of less than 2 seconds be deemed normal and included CRT in the Trauma Score. The value of 2 seconds for a normal CRT that was proposed by Dr Champion had been arbitrarily chosen by his nurse, and no evidence supporting that value has subsequently been found. CRT has been shown to be influenced by ambient temperature, age, sex, skin color, and the anatomical testing and lighting conditions. The most reliable and applicable site for CRT testing is the finger pulp (not at the fingernail), and the cut-off value for the normal CRT should be 3 seconds, not 2 seconds. A prolonged capillary refill time may be a sign of shock and can also indicate dehydration and may be a sign of dengue hemorrhagic fever and decreased peripheral perfusion. Prolonged capillary refill time may also suggest peripheral artery disease. == Use ==

Capillary refill time is a quick and cheap way to indicate decreased peripheral perfusion and may indicate cardiovascular or respiratory dysfunction. There is disagreement as to whether the test is useful, however, and it is poorly standardised. However, CRT can still be a useful test, especially for conditions of septic shock, where markers such as serum lactate levels take time to analyze. The ANDROMEDA-SHOCK-2 trial saw better patient outcomes by using CRT as a target for septic shock resuscitation compared to the usual standard of care. In veterinary medicine, poor gum CRT may be an contraindication for use of anaesthesia, as the likelihood of anaesthesia being fatal is higher if there is an underlying heart or lung problem. Gum CRT may also be used to monitor health during anaesthesia. ==See also==