Etymology: Fr, blanchir, to become white; L, testum, crucible
a test of blood circulation in the fingers or toes. Pressure is applied to a fingernail or toenail until normal color is lost. The pressure is then removed, and, if the circulation is normal, color should return almost immediately, within about 2 seconds. The time may be prolonged by dehydration; a compromise of circulation, such as arterial occlusion; hypovolemic shock; or hypothermia. See also Bowen technique, capillary refill.
blanch test, blanching test
A test of the integrity of the circulation performed by applying and then quickly releasing pressure to a fingernail or toenail. After losing color, the blanched nail normally regains a pink appearance within 2 seconds or less. Failure to do so suggests impaired blood flow to the extremity.Synonym: capillary nail refill test See: illustration