Some causes related to cardiovascular disease: Transient episodes of numbness and tingling in a single limb are often due to falling asleep in a position in which an artery is compressed. Once the affected limb is stretched and massaged for a few moments, feeling returns. While technically this is a "vascular problem," it is generally not associated with any actual vascular disease. It is purely a positional phenomenon.
Some causes related to other disorders: Persistent numbness and tingling in a limb is almost always related to a neurological problem.
Significance: Transient episodes occurring while asleep usually have little or no medical significance. Persistent episodes need a full medical evaluation.

