Reactive hyperaemia test

Reactive hyperaemia test:
Blood pressure cuff around thigh above knee - limb is elevated for several minutes  inflate cuff rapidly to just above systolic pressure – after 5 minutes rapidly reduce pressure – observe skin colour.
Normal  immediate red flush below level of cuff after cuff deflation – this progress down limb in 10 to 15 seconds – remains for 10 – 30 seconds then recedes – normal colour should return within 2 minutes.
If PVD – initial flush is cyanotic – progress down limb is delayed and recession of colour is delayed.

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