scholarly journals The Influence of Rate of Filling on Apparent Venous Distensibility in Man

1972 ◽  
Vol 50 (4) ◽  
pp. 310-316 ◽  
Author(s):  
Norman K. Hollenberg ◽  
Lars O. Boréus
Keyword(s):  
Blood Flow ◽  
Venous Occlusion ◽  
Transmural Pressure ◽  
Venous Occlusion Plethysmography ◽  
Volume Changes ◽  
External Pressures ◽  
Venous Distensibility ◽  
Venous Volume ◽  
Flow Changes ◽  
Venous Segment

The influence of the rate of filling on the relation between venous volume and transmural pressure in the human extremity was investigated with two techniques, venous occlusion plethysmography (leg) and infusion into an isolated venous segment (forearm). Both methods revealed a quantitatively important rate-related component in the response of veins to distension; the venous volume was lower at a given transmural pressure when filling was rapid. This component can serve as a local buffering mechanism, minimizing volume changes after sudden changes in postcapillary pressure such as occur with changes of posture or blood flow. Since blood flow and apparent venous distensibility are interrelated, flow changes must be taken into account in the interpretation of studies in which venous distensibility curves determined by plethysmography are used as an index of venous tone.It has also been demonstrated that the limb supported above heart level contains a minimal volume of blood which is not altered by external pressures up to 40 mm Hg.

Influence of leg position and environmental temperature on segmental volume expansion during venous occlusion plethysmography

2003 ◽  
Vol 104 (6) ◽  
pp. 599-605 ◽  
Author(s):  
Lennart JORFELDT ◽  
Torbjörn VEDUNG ◽  
Elisabeth FORSSTRÖM ◽  
Jan HENRIKSSON
Keyword(s):  
Blood Flow ◽  
Strain Gauge ◽  
Volume Expansion ◽  
Venous Blood ◽  
Venous Occlusion ◽  
Transmural Pressure ◽  
Sympathetic Tone ◽  
Venous Occlusion Plethysmography ◽  
Expansion Rate ◽  
Leg Position

Blood flow determinations by venous occlusion plethysmography applying the strain-gauge technique are frequently used. A problem with the strain-gauge technique is that the relationship between venous volume and transmural pressure is not linear and, furthermore, changes with the sympathetic tone. The present study tests the hypothesis that these factors lead to a redistribution of venous blood, which may impair the accuracy of the technique. The relative volume expansion rates of four leg segments were studied with the leg in different positions and at disparate temperatures, thereby inducing varying venous pressures and sympathetic tone (n=6). With elevated leg and relaxed veins (at 50 °C), the distal thigh showed a relatively low expansion rate (25.8±4.5 ml·min-1·l-1), whereas values in the calf segments were higher (34.5–39.0 ml·min-1·l-1). With lower initial transmural pressure, calf segments can increase their volume much more during occlusion compared with the distal thigh. In a higher transmural pressure region (lowered leg), the difference in compliance between limb segments is less. In this case, compliance and volume expansion rate was higher in the distal thigh (14.2, 13.5 and 22.2 ml·min-1·l-1 at 10, 20 and 50 °C respectively) than in the calf segments (for the distal calf: 6.4, 7.7 and 16.2 ml·min-1·l-1 respectively). There was a significant interaction (P<0.001) between temperature and leg position, indicating a higher degree of sympathetic vasoactivity in the calf. It is concluded that blood flow determination by strain-gauge plethysmography is less accurate, due to a potential redistribution of the venous blood. Therefore possible influences of variations in sympathetic tone and venous pressure must be considered even in intra-individual comparisons, especially in interventional studies.

scholarly journals The inability of venous occlusion air plethysmography to identify patients who will benefit from stenting of deep venous obstruction

2017 ◽  
Vol 33 (7) ◽  
pp. 483-491 ◽  
Author(s):  
Ralph LM Kurstjens ◽  
Fabio S Catarinella ◽  
Yee Lai Lam ◽  
Mark AF de Wolf ◽  
Irwin M Toonder ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Successful Treatment ◽  
Clinical Success ◽  
Duplex Ultrasound ◽  
Venous Occlusion ◽  
Venous Occlusion Plethysmography ◽  
Venous Obstruction ◽  
Venous Volume ◽  
Air Plethysmography ◽  
One Year

Background The aim of this study was to assess whether venous occlusion plethysmography can be used to identify venous obstruction and predict clinical success of stenting. Method Receiver operated characteristic curves were used to determine the ability of venous occlusion plethysmography to discriminate between the presence and absence of obstruction, measured by duplex ultrasound and magnetic resonance venography, and to discriminate between successful and non-successful stenting, measured by VEINES-QOL/Sym. Result Two hundred thirty-seven limbs in 196 patients were included. Areas under the curve for post-thrombotic obstruction were one-second outflow volume 0.71, total venous volume 0.69 and outflow fraction 0.59. Stenting was performed in 45 limbs of 39 patients. Areas under the curve for identifying patients with successful treatment at one year after stenting were 0.57, 0.54 and 0.63, respectively. Conclusion Venous occlusion plethysmography cannot be used to identify venous obstruction proximal to the femoral confluence or to distinguish which patients will benefit from treatment.

THE EFFECT OF LOCAL TEMPERATURE ON INDIRECT VASODILATATION IN THE FEET

1967 ◽  
Vol 45 (1) ◽  
pp. 63-73 ◽  
Author(s):  
Peter Gaskell ◽  
Garth M. Bray
Keyword(s):  
Blood Flow ◽  
Venous Occlusion ◽  
Venous Occlusion Plethysmography ◽  
Local Temperature ◽  
Cool Water ◽  
Arterial Blood

Lewis and Pickering reported in 1933 that warming occurred later in cool than in warm fingers in response to body heating. Factors which may be responsible were investigated. Measurement of rate of blood flow in the feet by venous occlusion plethysmography during body heating showed that vasodilatation in the feet occurred at the same time in a cool foot (18 to 23 °C) as in a warm (30 to 35 °C) but that warming of the cooler foot might be delayed for some time until the increase in flow was 0.5 ml/100 ml of foot per minute or more. In control experiments, with both feet in cool water or both in warm, the increase in blood flow during body heating started at the same time in both feet. Warming also began at the same time in both feet, but in the cool control experiments, warming often began later than did increase in flow. It is suggested that precooling of arterial blood may account for the delay in warming when the extremity is initially cool and the increase in blood flow is at first small during indirect vasodilatation.

Effects of nitroglycerin on forearm haemodynamics in patients with cirrhosis

1988 ◽  
Vol 74 (4) ◽  
pp. 433-436 ◽  
Author(s):  
M. Isabel Jiron ◽  
Samuel S. Lee ◽  
Raimondo Cerini ◽  
Domenico Pugliese ◽  
Antoine Hadengue ◽  
...  
Keyword(s):  
Blood Flow ◽  
Forearm Blood Flow ◽  
Inverse Correlation ◽  
Venous Occlusion ◽  
Group Iii ◽  
Dilatory Response ◽  
Age Related ◽  
Group I ◽  
Venous Distensibility ◽  
Group Ii

1. Basal forearm haemodynamics were studied by venous occlusion plethysmography in three groups of subjects: group I, healthy controls, group II, patients with cirrhosis age- and sex-matched with group I, and group III, an older group of patients with cirrhosis. Subsequently, responses to sublingual nitroglycerin were measured in group I and II subjects. 2. Controls responded to nitroglycerin with an increase in venous distensibility; group II patients had higher initial venous distensibility but did not respond to nitroglycerin. No other variables in either group were affected by nitroglycerin. 3. Group II and III patients differed in forearm blood flow and vascular resistance and venous distensibility. A significant inverse correlation was found between age and forearm blood flow (r = −0.57, P < 0.001) in all patients with cirrhosis. 4. We conclude that (a) venous tone is reduced in cirrhosis, possibly as a result of chronic venodilatation; (b) this venodilatation impedes further dilatory response to a small dose of nitroglycerin; (c) cirrhosis is also associated with age-related decreases in peripheral haemodynamics.

Sign in / Sign up

Export Citation Format

Share Document