Evaluation of Umbilical Venous Flow Volume Measured Using Ultrasound Compared to Circuit Flow Volume in the EXTra‐uterine Environment for Neonatal Development (EXTEND) System in Fetal Sheep

Deriving cerebral metabolic rate of oxygen consumption (CMRO2) from blood oxygenation level-dependent (BOLD) signals involves a flow-volume parameter (α), reflecting total cerebral blood volume changes, and a calibration constant ( M). Traditionally, the former is assumed a fixed value and the latter is measured under alterations in fixed inspired fractional concentrations of carbon dioxide. We recently reported on reductions in M-variability via precise control of end-tidal pressures of both hypercapnic (HC) and hyperoxic (HO) gases. In light of these findings, our aim was to apply the improved calibration alternatives to neuronal activation, making use of their distinct vasoactive natures to evaluate the α-value. Nine healthy volunteers were imaged at 3 T while simultaneously measuring BOLD and arterial spin-labeling signals during controlled, graded, HC, and HO, followed by visual (VC) and sensorimotor cortices (SMC) activation. On the basis of low M- and CMRO2-variability, the comparison of these calibration alternatives accurately highlighted a reduced venous flow—volume relationship (α = 0.16 ± 0.02, with αVC = 0.12 ± 0.04, and αSMC = 0.20 ± 0.02), as appropriate for BOLD modeling.

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Manual lymphatic drainage in chronic venous disease: A duplex ultrasound study

Phlebology The Journal of Venous Disease ◽

10.1177/0268355513502787 ◽

2013 ◽

Vol 29 (10) ◽

pp. 667-676 ◽

Cited By ~ 6

Author(s):

Rute Sofia dos Santos Crisóstomo ◽

Miguel Sandu Candeias ◽

Ana Margarida Martins Ribeiro ◽

Catarina da Luz Belo Martins ◽

Paulo AS Armada-da-Silva

Keyword(s):

Blood Flow ◽

Saphenous Vein ◽

Great Saphenous Vein ◽

Femoral Vein ◽

Lymphatic Drainage ◽

Chronic Venous Disease ◽

Venous Disease ◽

Flow Volume ◽

Manual Lymphatic Drainage ◽

Venous Flow

Objectives To compare the effect of call-up and reabsorption maneuvers of manual lymphatic drainage on blood flow in femoral vein and great saphenous vein in patients with chronic venous disease and healthy controls. Methods Forty-one subjects participated in this study (mean age: 42.68(15.23)), 23 with chronic venous disease (chronic venous disease group) with clinical classification C1–5 of clinical-etiological-anatomical-pathological (CEAP) and 18 healthy subjects (control group). Call-up and reabsorption maneuvers were randomly applied in the medial aspect of the thigh. The cross-sectional areas, as well as the peak and the mean blood flow velocity at femoral vein and great saphenous vein, were assessed by Duplex ultrasound at the baseline and during maneuvers. The venous flow volume changes were calculated. Results The venous flow volume in femoral vein and great saphenous vein increased during both manual lymphatic drainage maneuvers and in both groups ( P < 0.05). The two maneuvers had a similar effect on femoral vein and great saphenous vein hemodynamics, and in both the chronic venous disease and control groups. As a result of the call-up maneuver, the flow volume augmentations, as a result of call-up maneuver, decreased with the severity of chronic venous disease in those patients measured by the clinical classification of CEAP ( r = −0.64; P = 0.03). Conclusions Manual lymphatic drainage increases the venous blood flow in the lower extremity with a magnitude that is independent from the specific maneuver employed or the presence of chronic venous disease. Therefore, manual lymphatic drainage may be an alternative strategy for the treatment and prevention of venous stasis complications in chronic venous disease.

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