Allen's test


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Related to Allen's test: Adson's test, Homans sign, Buerger's test

Allen's test

 [al´enz]
a test for occlusion of radial or ulnar arteries: the patient makes a tight fist so as to express the blood from the skin of the palm and fingers; the examiner makes digital compression on either the radial or ulnar artery. Failure of blood to return to the palm and fingers when the hand is opened indicates obstruction of the blood flow in the artery that has not been compressed. Either this test or a doppler ultrasound examination should always be performed prior to insertion of a radial artery line.

Allen's test

[Edgar Van Nuys Allen, American physician, 1893-1986],
a test for the patency of the radial artery after insertion of an indwelling monitoring catheter. The patient's hand is formed into a fist while the nurse compresses the ulnar artery. Compression continues while the fist is opened. If blood perfusion through the radial artery is adequate, the hand should flush and resume its normal pinkish coloration. The accuracy and utility of the Allen's test has been questioned in the research literature.
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Allen's test

Allen's test

A clinical test used to evaluate ulnar-artery patency before radial-artery cannulation or radial-artery harvesting for coronary-artery bypass grafting.
Method Simultaneous compression of both the radial and ulnar arteries, followed by exsanguination of blood from the palm by repeated clenching and unclenching of the fist. The pressure over the ulnar artery is then released while maintaining pressure over the radial artery. A 5–6 second delay in flushing of the palm suggests abnormal ulnar-artery patency.

Allen's test

Rehabilitation medicine A test used to determine patency of the ulnar or radial artery; the hand is clenched to force blood out; if the blood does not flow back into the hand rapidly, one or more arteries are stenosed or occluded–eg, due to throacic outlet syndrome
References in periodicals archive ?
Patients referred for coronary catheterization who had a normal radial pulse and a good collateral flow via the palmar arch as indicated by a normal Allen's test, were considered for transradial catheterization.
Before attempting transradial access, it is important to ascertain that the Allen's test is normal (positive), thus confirming an adequate collateral arterial supply from the ulnar artery.
Allen's test was performed for all patients in order to assess the circulation of ulnar and RA.
The Allen's test was repeated for all patients with weaker RAP.