Assessment of arterial and venous circulation in upper and lower extremities by venous occlusion strain gauge plethysmography. Normal values and reproducibility.

In 10 healthy men aged 25 to 35 years the variability of basal arterial blood flow (BBF), maximal arterial blood flow (MBF) as induced by a 5-minute arterial occlusion, total venous capacity (TVC) and venous emptying rate (VER) were studied in both the upper and lower limbs by repeated measurements over 5 hours under strictly standardised conditions using an automatic venous occlusion plethysmograph. Mean values obtained at the initial examination in the forearm and calf respectively were: BBF: 3.7 +/- 1.2 and 2.3 +/- 0.6, MBF: 24.2 +/- 6.5 and 28.0 +/- 8.9, VER: 64.0 +/- 14.0 and 66.0 +/- 16.4 ml/min per 100 g tissue, TVC: 3.5 +/- 0.9 and 3.7 +/- 0.8 ml per 100 g tissue. At 45 min there was a general trend towards lower values in particular regarding BBF and TVC. Reproducibility in terms of coefficients of variation computed from duplicate determinations were 25% and 13% for BBF and 11% and 7% for MBF measurement in the forearm and calf respectively and below 10% for TVC and VER. The low reproducibility of BBF measurement is apparently due to a high degree of random biological variability in particular concerning the forearm vascular bed which makes the forearm poorly suitable for studying effects of interventions in cardiovascular control.