Measurements of vascular function using strain-gauge plethysmography: technical considerations, standardization, and physiological findings

Abstract

The main purpose of the present study was to examine the relationships between measures of fitness [estimated peak oxygen consumption (V(O2) peak) and handgrip strength] and forearm vascular function in 55 young (22.6 +/- 3.5 yr) adults. In addition, the present study considered methodological and technical aspects regarding the examination of the venous system using mercury in-Silastic strain-gauge plethysmography (MSGP). Forearm venous capacitance and outflow were examined using five different [7, 14, 21, 28, and 35 mmHg < diastolic blood pressure (DBP)] venous occlusion pressures and after a 5- and 10-min period of venous occlusion. A pressure of 7 mmHg < DBP and a period of 10 min venous occlusion produced the greatest (P < 0.05) venous capacitance and outflow, without altering arterial indexes. Reproducibility of forearm arterial and venous indexes were evaluated at rest and after 5 min of upper arm arterial occlusion at 240 mmHg on three different occasions within 10 days with the interclass correlation coefficient ranging from 0.70 and 0.94. Estimated V(O2) peak correlated with postocclusion arterial inflow (r = 0.54, P = 0.012) and resting venous outflow (r = 0.56, P = 0.016). Finally, handgrip strength was associated with venous capacitance (r = 0.57, P = 0.007) and outflow (r = 0.67, P = 0.001). These results indicate that the examination of forearm vascular function using MSGP is reproducible. Moreover, the data show the importance of careful consideration of the selection of venous occlusion pressure and period when implementing these measures in longitudinal trials. Finally, the associations between fitness and venous measures suggest a link between venous function and exercise performance.

Relationship Between Vascular and Physical Function in Individuals with Peripheral Neuropathy

“…In contrast, both KE and KF were significantly related to the VO t1/2 . These findings further confirm data from our laboratory suggesting that muscular fitness is related to venous function [31]. The associations suggest the contribution of the venous system to physical function is beyond the typical role as a "passive volume reservoir".…”

Oral l-arginine supplementation improves endothelial function and ameliorates insulin sensitivity and inflammation in cardiopathic nondiabetic patients after an aortocoronary bypass

“…Therefore, statistical analysis is performed in 16 patients treated with L-arginine and 14 patients treated with placebo. The sample size of patients for each group was estimated taking advantage of previous studies in which reactive hyperemia of FBF marker of endothelial vasodilation [11][12][13] was evaluated after long-term oral administration of L-arginine (6 g daily, 6 months). Therefore, we have designed the study to be large enough to be able to detect, with a β = 80% and α = 5%, an increase in reactive hyperemia of FBF from 5% with placebo to 30% with L-arginine treatment; and we evaluated that the final sample for each group was at least 14 patients.…”

Effects of growth hormone treatment on arginine to asymmetric dimethylarginine ratio and endothelial function in patients with growth hormone deficiency

“…Three plethysmographic measurements were averaged to obtain FBF at baseline and during reactive hyperemia [17]. This method has been recently validated, and results are reported in Alomari et al [18]. Moreover, it was demonstrated that the measurement of endothelial function by strain gauge plethysmography has a high correlation with brachial artery ultrasound [19].…”