Venous Pumps of The Hand

1996 ◽  
Vol 21 (5) ◽  
pp. 595-599 ◽  
Author(s):  
P. SIMONS ◽  
P. COLERIDGE SMITH ◽  
W. R. LEES ◽  
D. A. MCGROUTHER
Keyword(s):  
Muscle Contraction ◽  
Doppler Ultrasound ◽  
Venous Return ◽  
Venous Blood ◽  
Blood Velocity ◽  
Clinical Applications ◽  
Oedema Formation ◽  
Velocity Increase ◽  
Common Causes ◽  
Underlying Mechanisms

Oedema remains one of the most common causes of hand stiffness. Local venous return is intimately associated with oedema formation and management. To elucidate, the underlying mechanisms of venous return, the venous pumping systems in the hand were objectively and quantitatively investigated using Doppler ultrasound, cadaveric dissection and venography. It was demonstrated that functionally there are three independent venous systems: the superficial palmar, deep palmar and dorsal veins, which are activated by palm compression, isometric intrinsic muscle contraction, and dorsum compression, respectively. Each system was investigated independently and found to increase venous blood velocity in both the cephalic and ulnar veins. These systems were also shown to act in synergy, producing the greatest velocity increase when concurrently activated during fist-clenching. The volume of blood pumped during fist-clenching could also be potentiated by preloading by digit abduction. The clinical applications of these findings are discussed.

Effects of graduated compression stockings, local vibration and their combination on popliteal venous blood velocity

2020 ◽  
Vol 35 (7) ◽  
pp. 505-512
Author(s):  
Loïc Espeit ◽  
Thomas Lapole
Keyword(s):  
Pilot Study ◽  
Prone Position ◽  
Doppler Ultrasound ◽  
Healthy Subjects ◽  
Peak Velocity ◽  
Venous Blood ◽  
Blood Velocity ◽  
Compression Stockings ◽  
Local Vibration ◽  
Graduated Compression Stockings

Objectives The purpose of this pilot study was to examine and compare the effects of graduated compression stockings, local vibration, and combined graduated compression stockings and local vibration on popliteal venous blood velocity. Method Twenty-four healthy subjects received four 15 min interventions (control, graduated compression stockings alone, local vibration alone, and combined graduated compression stockings and local vibration), while resting inactive in the prone position. Popliteal vein blood velocity was investigated before (PRE) and at the end (POST) of each intervention using Doppler ultrasound. Results At POST, peak velocity was reported to be 26.3 ± 53.5% ( p <  0.05) greater for local vibration than control (CONT). Peak velocity was 46.2 ± 54.6% ( p <  0.001) and 21.1 ± 37.6% ( p <  0.01) higher for graduated compression stockings than CONT and local vibration, respectively. Graduated compression stockings + local vibration presented 64.1 ± 58.0% ( p <  0.001), 38.4 ± 52.4% ( p <  0.001) and 15.0 ± 31.6% ( p <  0.05) greater values than CONT, local vibration and graduated compression stockings, respectively. Conclusions This study demonstrated an increase in popliteal venous blood velocity after graduated compression stockings and local vibration application. Their combination provided the greatest effects.

scholarly journals Present and future utility of computed tomography scanning in the assessment and management of COPD

2016 ◽  
Vol 48 (1) ◽  
pp. 216-228 ◽  
Author(s):  
Kristoffer Ostridge ◽  
Tom M.A. Wilkinson
Keyword(s):  
Computed Tomography ◽  
Clinical Applications ◽  
Wall Thickening ◽  
Chronic Obstructive ◽  
Clinical Tool ◽  
Obstructive Pulmonary Disease ◽  
Lung Structure ◽  
Computed Tomography Scanning ◽  
Underlying Mechanisms ◽  
Future Utility

Computed tomography (CT) is the modality of choice for imaging the thorax and lung structure. In chronic obstructive pulmonary disease (COPD), it used to recognise the key morphological features of emphysema, bronchial wall thickening and gas trapping. Despite this, its place in the investigation and management of COPD is yet to be determined, and it is not routinely recommended. However, lung CT already has important clinical applications where it can be used to diagnose concomitant pathology and determine which patients with severe emphysema are appropriate for lung volume reduction procedures. Furthermore, novel quantitative analysis techniques permit objective measurements of pulmonary and extrapulmonary manifestations of the disease. These techniques can give important insights into COPD, and help explore the heterogeneity and underlying mechanisms of the condition. In time, it is hoped that these techniques can be used in clinical trials to help develop disease-specific therapy and, ultimately, as a clinical tool in identifying patients who would benefit most from new and existing treatments. This review discusses the current clinical applications for CT imaging in COPD and quantification techniques, and its potential future role in stratifying disease for optimal outcome.

How Much Training Is Too Much?

2017 ◽  
Vol 32 (1) ◽  
pp. 61-62 ◽  
Author(s):  
Bronwen J Ackermann
Keyword(s):  
Approximate Determination ◽  
International Studies ◽  
Common Causes ◽  
Or Practice ◽  
Performance Domains ◽  
Underlying Mechanisms ◽  
Rest Breaks ◽  
Performing Artist ◽  
Musculoskeletal Performance

Managing training practices in elite performance domains is recognised to play an important role in preventing musculoskeletal overload, and hence reducing the risk of overuse-related injuries. In international studies spanning four decades, the duration of playing, especially in combination with sudden increases in playing and inadequate rest breaks, remains one of the most common causes of injuries. With musculoskeletal performance in occupational and sports domains, both the work:rest ratio and the acute:chronic workload ratio are considered critical in making an approximate determination in the length of training sessions. However, there are many complex underlying mechanisms that interact with the duration of training and how long a performing artist may safely rehearse or practice. Instead of trying to set rigid timelines, particularly for personal practice/training, recognising mental and physical signs of fatigue may be more useful to inform the performing artist when to stop and rest rather than to persist.

EFFECT OF ANKLE EXERCISE ON VENOUS BLOOD VELOCITY

CHEST Journal ◽  
2008 ◽  
Vol 134 (4) ◽  
pp. 43P
Author(s):  
Bakhtiar Mirza ◽  
Aaref Badshah ◽  
Mahmud Zamlut ◽  
Syed Ahsan ◽  
Fadi Matta ◽  
...  
Keyword(s):  
Venous Blood ◽  
Blood Velocity

scholarly journals To Doppler or not to Doppler

2015 ◽  
Vol 64 (2) ◽  
pp. 84-91
Author(s):  
William A Goh ◽  
Zalud Ivica
Keyword(s):  
Doppler Ultrasound ◽  
New Technologies ◽  
Rapid Development ◽  
Power Doppler ◽  
Clinical Applications ◽  
Growth Restriction ◽  
Ductus Venosus ◽  
4D Ultrasound ◽  
Doppler Ultrasound Imaging ◽  
3D Power Doppler

This review aims to provide the reader with an update on the present and potential clinical applications in Doppler ultrasound in perinatal medicine. Umbilical artery Doppler plays an important role in the management of intrauterine growth restriction (IUGR) and preeclampsia and aids in twin-to-twin transfusion syndrome management while notching in the waveform is a predictor of umbilical cord abnormalities. Middle cerebral artery Doppler reliably detects fetal anemia and may be useful in the assessment of IUGR as well. Abnormal uterine artery Doppler may play a role in predicting growth restriction, hypertensive disorders of pregnancy and preterm delivery. Abnormal ductus venosus waveforms can also be used to predict adverse fetal outcome and may allow for better timing of delivery while umbilical venous pulsations may be a sensitive marker for fetal heart failure in hydropic pregnancies. 3D power Doppler allows better small vessel visualization that is not affected by angle of insonation and has been used to diagnose placental and cord abnormalities. Significant improvements have recently occurred, improving the visualization and evaluation of placental vascularity, resulting from enhancements in delineation of tissue detail through electronic compounding and harmonics, as well as enhancements in signal processing of frequency- and/ or amplitude-based color Doppler ultrasound. Spatial representation of vascularity can be improved by utilizing 3D processing. Greater sensitivity of 3D Doppler ultrasound to macro- and microvascular flow has provided improved anatomic and physiologic assessment throughout pregnancy. The rapid development of these new ultrasound techniques will continue to enlarge the scope of clinical applications in placental studies. As clinical experience with these new technologies increase and as the technology improves further, it is reasonable to expect that 3D Doppler and 4D ultrasound will be complementary addition to well established 2D Doppler ultrasound imaging.

Timed synchronization of muscle contraction to heartbeat enhances muscle hyperemia

2020 ◽  
Vol 128 (4) ◽  
pp. 805-812
Author(s):  
Gaia Giuriato ◽  
Stephen J. Ives ◽  
Cantor Tarperi ◽  
Lorenzo Bortolan ◽  
Federico Ruzzante ◽  
...  
Keyword(s):  
Blood Flow ◽  
Muscle Contraction ◽  
Blood Velocity ◽  
Muscle Contractions ◽  
Velocity Spectrum ◽  
Functional Hyperemia ◽  
Central Hemodynamics ◽  
Active Muscle ◽  
Vascular Conductance ◽  
Significant Difference

Blood flow (BF) to exercising muscles is susceptible to variations of intensity, and duration of skeletal muscle contractions, cardiac cycle, blood velocity, and vessel dilation. During cyclic muscle activity, these elements may change proportionally with or without direct optimal temporal alignment, likely influencing BF to active muscle. Ideally, the pulsed delivery of blood to active muscle timed with the inactive phase of muscle duty-cycle would enhance the peak and average BF. To investigate the phenomenon of muscle contraction and pulse synchronicity, electrically evoked muscle contractions (trains of 20 Hz, 200-ms duration) were synchronized with each systolic phase of the anterograde blood velocity spectrum (aBVS). Specifically, unilateral quadriceps contractions matched in-phase (IP) with the aBVS were compared with contractions matched out-of-phase (OP) with the aBVS in 10 healthy participants (26 ± 3 yr). During each trial, femoral BF of the contracting limb and central hemodynamics were recorded for 5 min with an ultrasound Doppler, a plethysmograph, and a cardioimpedance device. At steady state (5th min) IP BF (454 ± 30 mL/min) and vascular conductance (4.3 ± 0.2 mL·min−1·mmHg−1), and OP MAP (108 ± 2 mmHg) were significantly lower ( P < 0.001) in comparison to OP BF (784 ± 25 mL/min) and vascular conductance (6.7 ± 0.2 mL·min−1·mmHg−1), and IP MAP (113 ± 3 mmHg). On the contrary, no significant difference (all, P > 0.05) was observed between IP and OP central hemodynamics (HR: 79 ± 10 vs. 76 ± 11 bpm, CO: 8.0 ± 1.6 vs. 7.3 ± 1.6 L/min), and ventilatory patterns (V̇e:14 ± 2 vs. 14 ± 1 L/min, V̇o2:421 ± 70 vs. 397 ± 34 mL/min). The results suggest that muscle contractions occurring during OP that do not interfere with aBVS elicit a maximization of muscle functional hyperemia. NEW & NOTEWORTHY When muscle contraction is synchronized with the pulsed delivery of blood flow to active muscle, muscle functional hyperemia can be either maximized or minimized. This suggests a possibility to couple different strategies to enhance the acute and chronic effects of exercise on the cardiovascular system.

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