Surgery – MCQ 79 – Allen’s test
Allen’s test is useful in evaluating:
A. Thoracic outlet compression
B. Presence of cervical rib
C. Integrity of palmar arch
D. Digital blood flow
Correct answer : C. Integrity of palmar arch
How to perform allen’s test: (To check for patency of radial and ulnar arteries and to confirm integrity of the palmar arterial arch between them)
- The patient makes a tight fist
- The examiner compresses the radial and ulnar arteries distally
- The fist is released and compression of the ulnar artery is released
- The speed of return of colour to the palm is looked for
- Steps 1 and 2 are repeated, but release the radial artery compression instead of the ulnar artery
- Again look for speed of return of colour to the palm
Normally, the colour should return in 5-7seconds. This indicates that the arteries and the palmar arch is patent and functioning well.
