Local blood flux in skin and muscle during voluntary hyperventilation in healthy controls and patients with hyperventilation syndrome.

Laser Doppler fluxmetry was used to analyze local blood flux in the anterior tibial muscle and the skin of the calf simultaneously during 3 min of hyperventilation. Examinations were performed in 10 controls and 10 patients with a hyperventilation syndrome in order to evaluate a possible different vascular response to the provocation test. During hyperventilation, mean muscle blood flux increased in both groups. In controls, flux augmented from 23.4 +/- 12.3 arbitrary units (AU) to 51.6 +/- 28.3 AU (p < 0.05) and in patients from 21.6 +/- 10.8 AU to 45.0 +/- 26.4 AU (p < 0.05). The changes of skin blood flux during hyperventilation were not significant. The flux response did not differ significantly in controls and patients. Using the laser Doppler technique we were able to confirm muscular vasodilatation previously reported during short-term hyperventilation. Possible mechanisms include release of vasoactive substances and/or a stimulation of the autonomic nervous system.