Abstract
The variability of the venous pressure response (reflecting the venous tone reaction) to a deep breath was studied in 16 individuals, the response being measured in superficial veins of the hand, forearm, and foot by the occluded limb technique. In general, the venous pressure response was similar in hand and forearm but smaller in foot than in hand. By standardizing the experimental conditions a good reproducibility could be attained within the single subject. The variability between different subjects was still pronounced, however, and a main reason may be differences in the ‘background’ level of nervous venous tone. Important causes of variability for the venous pressure response have been found to be the venous distending pressure (experimentally varied by venous stasis) and the ‘background’ venous tone (experimentally varied by indirect cooling and warming).