Ultrasound: a reproducible method to measure conduit vein compliance

2005 ◽  
Vol 98 (5) ◽  
pp. 1878-1883 ◽  
Author(s):  
Patricia C. E. de Groot ◽  
Michiel W. P. Bleeker ◽  
Maria T. E. Hopman

Classical venous occlusion plethysmography (VOP) of the leg, often used to assess venous compliance, measures properties of the whole calf, including volume changes at the arterial side and the interstitial fluid accumulation that occurs as a result of the enhanced capillary pressure during venous occlusion. We present an ultrasound technique to measure the compliance of one major conduit vein in the leg. Ultrasound measurements of the popliteal vein were compared with classical VOP measurements, which were performed simultaneously in one subject. Six healthy individuals were measured on three occasions to assess short- and long-term reproducibility of the measurements. Six motor complete spinal cord-injured (SCI) individuals were included to compare venous compliance in subjects with known pathological changes of the venous system with controls. The ultrasound and VOP measurements of venous compliance correlated significantly ( r2 = 0.39, P = 0.001). Ultrasound provides reproducible measurements with short- and long-term coefficients of variation ranging from 10 to 15% for popliteal vein compliance and from 2 to 9% for absolute diameters at the different venous pressure steps. In addition, by using ultrasound, we were able to detect an 80% reduction in the compliance of the popliteal vein in SCI individuals compared with controls ( P < 0.01). In conclusion, ultrasound is a suitable and reproducible method to measure conduit vein compliance and provides the possibility to specifically assess compliance of one vein instead of the whole calf.

1997 ◽  
Vol 82 (6) ◽  
pp. 1726-1733 ◽  
Author(s):  
Francis Louisy ◽  
Philippe Schroiff ◽  
Antonio Güell

Louisy, Francis, Philippe Schroiff, and Antonio Güell.Changes in leg vein filling and emptying characteristics and leg volumes during long-term head-down bed rest. J. Appl. Physiol. 82(6): 1726–1733, 1997.—Leg venous hemodynamics [venous distensibility index (VDI), arterial flow index (AFI), half-emptying time (T1/2)], and leg volumes (LV) were assessed by mercury strain-gauge plethysmography with venous occlusion and volometry, respectively, in seven men before, during, and after 42 days of 6° head-down bed rest. Results showed a high increase in VDI up to day 26 of bed rest (+50% vs. control at day 26, P < 0.05), which tended to subside thereafter (+20% increase vs. control value at day 41, P < 0.05). VDI changes were associated with parallel changes in T1/2 (+54% vs. control at day 26 of bed rest, P < 0.05, and +25% vs. control at day 41, P < 0.05) and with a decrease in AFI (−49% at day 41 vs. control, P < 0.05). LV continuously decreased throughout bed rest (−13% vs. control at day 41, P < 0.05) but was correlated with VDI only during the first month of bed rest. These results show that during long-term 6° head-down bed rest alterations of leg venous compliance are associated with impairment of venous emptying capacities and arterial flow. Changes in skeletal muscle mass and fluid shifts may account for venous changes during the first month of bed rest but, subsequently, other physiological factors, to be determined, may also be involved in leg venous hemodynamic alterations.


VASA ◽  
2013 ◽  
Vol 42 (5) ◽  
pp. 357-362 ◽  
Author(s):  
Jiří Spáčil

Background: The aim of this study was to assess the haemodynamic significance of popliteal vein compression by full knee extension. Patients and methods: We examined patients without a history of previous deep vein thrombosis with the knee slightly flexed and then fully extended. The popliteal vein diameters and venous pressures in 61 subjects (116 limbs) were examined using duplex ultrasonography and photoplethysmography. The venous outflow in 50 patients was assessed using photoplethysmography. Results: The diameter of the popliteal vein in semiflexion was 7.7 (+ 1,5) mm, in extension it was reduced to 4.3 (+ 1,7) mm (p < 0.001). Venous pressure in the big toe rose from 12.3 (+ 6,1) mmHg to 15.5 (+ 7,4) (p < 0.001). We have demonstrated the reduction of maximum venous outflow in 50 patients from 65.8 (+ 24) %/min to 60.1 (+ 23) %/min (p < 0.01) immediately after loosening the 2-minute venous occlusion, as well as outflow reduction during subsequent seconds. Conclusions: Our results provide evidence of haemodynamically significant popliteal vein compression in full extension of the limb. Clinically, the compression may play a role as a risk factor for venous thrombosis in immobilized patients, particularly during operations.


2008 ◽  
Vol 104 (5) ◽  
pp. 1374-1380 ◽  
Author(s):  
Colin N. Young ◽  
Raju Y. Prasad ◽  
Adam M. Fullenkamp ◽  
Michael E. Stillbower ◽  
William B. Farquhar ◽  
...  

The purpose of the present study was to determine whether ultrasound is a useful tool to measure the venous characteristics of the lower extremity during a standard venous collecting cuff deflation protocol. To accomplish this, lower extremity pressure-cross-sectional area (CSA) and pressure-volume relationships were measured in eight (25 ± 1 yr) supine subjects. Popliteal vein CSA was assessed by using high-resolution ultrasound, while calf volume changes were simultaneously assessed by using venous occlusion plethysmography (VOP). Pressure-CSA and pressure-volume relationships were assessed at baseline, during the cold pressor (CP) test, and following sublingual nitroglycerin (NTG) administration. Relationships were modeled with a quadratic regression equation, and β1 and β2 were used as indexes of venous compliance. Popliteal vein regression parameters β1 (8.485 ± 2.616 vs. 7.638 ± 2.664, baseline vs. CP; 8.485 ± 2.616 vs. 7.734 ± 3.076, baseline vs. NTG; both P > 0.05) and β2 (−0.0841 ± 0.0241 vs. −0.0793 ± 0.0242, baseline vs. CP; −0.0841 ± 0.0241 vs. −0.0771 ± 0.0280, baseline vs. NTG; both P > 0.05) were not affected by CP or NTG. Similarly, calf regression parameters β1 and β2, obtained with VOP, were not altered during either trial. Intraclass correlations for venous compliance assessed with ultrasound and VOP were 0.92 and 0.97, respectively, indicating acceptable reproducibility. These data suggest that ultrasound is a functional and reproducible tool to assess the venous characteristics of the lower extremity, in addition to VOP. Additionally, popliteal vein and calf compliance were not affected by the CP test or NTG.


Swiss Surgery ◽  
2001 ◽  
Vol 7 (1) ◽  
pp. 20-24 ◽  
Author(s):  
Robert ◽  
Mariéthoz ◽  
Pache ◽  
Bertin ◽  
Caulfield ◽  
...  

Objective: Approximately one out of five patients with Graves' disease (GD) undergoes a thyroidectomy after a mean period of 18 months of medical treatment. This retrospective and non-randomized study from a teaching hospital compares short- and long-term results of total (TT) and subtotal thyroidectomies (ST) for this disease. Methods: From 1987 to 1997, 94 patients were operated for GD. Thirty-three patients underwent a TT (mostly since 1993) and 61 a ST (keeping 4 to 8 grams of thyroid tissue - mean 6 g). All patients had received propylthiouracil and/or neo-mercazole and were in a euthyroid state at the time of surgery; they also took potassium iodide (lugol) for ten days before surgery. Results: There were no deaths. Transient hypocalcemia (< 3 months) occurred in 32 patients (15 TT and 17 ST) and persistent hypocalcemia in 8 having had TT. Two patients developed transient recurrent laryngeal nerve palsy after ST (< 3 months). After a median follow-up period of seven years (1-15) with five patients lost to follow-up, 41 patients having had a ST are in a hypothyroid state (73%), thirteen are euthyroid (23%), and two suffered recurrent hyperthyroidism, requiring completion of thyroidectomy. All 33 patients having had TT - with follow-ups averaging two years (0.5-8) - are receiving thyroxin substitution. Conclusions: There were no instances of persistent recurrent laryngeal nerve palsy in either group, but persistent hypoparathyroidism occurred more frequently after TT. Long after ST, hypothyroidism developed in nearly three of four cases, whereas euthyroidy was maintained in only one-fourth; recurrent hyperthyroidy was rare.


Author(s):  
Ian Neath ◽  
Jean Saint-Aubin ◽  
Tamra J. Bireta ◽  
Andrew J. Gabel ◽  
Chelsea G. Hudson ◽  
...  

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