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[Determination of venous capacity and flow by plethysmography with occlusion of the veins].

These examinations are based on the knowledge that mercury-in-rubber strain gauge method for venous occlusion plethysmography is suitable for measuring the venous capacity and venous return. This research reports on the value of this method in diagnostics. The results are as follows: the venous capacity decreases markedly in the group of patients with deep vein occlusions of the legs. However, it is not possible, basing on the measurements, to differentiate between occlusions above and those below the knee. The same applies to multiple occlusions in the same vein meaning that venous occlusions in the deep veins of the lower limb cannot be examined separately. The results of a single patient are mostly but not always similar to those of this corresponding group. Therefore venous occlusion plethysmography does not have the same diagnostic value as phlebography in deep vein occlusions for the individual patient.

Blood Flow Velocity↗
PubMed1984

A combined study of the strain gauge plethysmography and I-125 fibrinogen leg scan in the differentiation of deep vein thrombosis and postphlebitic syndrome.

The fallibility of the clinical diagnosis of deep venous thrombosis (DVT) and postphlebitic syndrome has led to a variety of noninvasive diagnostic modalities, e.g, Doppler ultrasound, plethysmography, and radionuclide phlebography. The purpose of this study is to analyze the value of combined strain gauge plethysmography (SPG) and I-125 fibrinogen leg scanning in the differentiation of DVT and postphlebitic syndrome. Using strain gauge plethysmograph, 600 studies were performed on 502 patients. The maximum venous outflow (MVO) was calculated. An MVO of 20 cm3/100 cm3 of tissue/min or above was considered normal, and MVO of less than 20 cm3 was abnormal. Of those, 150 limbs had I-125 fibrinogen leg scan and venograms. Of 82 normal SPG, when compared with venograms, 75 were normal, five had postphlebitic syndrome, and two had DVT (97.6% true-negative). Sixty-eight legs had positive SPG, 46 of which had DVT (67.6% true-positive), 21 had postphlebitic syndrome (30.9%), and one was normal (1.5% false-positive). When rubber tourniquets were placed lightly on each leg between the strain gauge and the thigh cuff, 12 legs changed from positive SPG to negative SPG; 56 legs only had positive SPG. Forty-six of these had DVT (82.1% true-positive), nine had postphlebitic syndrome, and one was normal. When positive SPG was combined with positive leg scan, the accuracy raised to 95.6% (44 of 46 legs). If the SPG was positive but the leg scan was negative, the possibility of postphlebitic syndrome was most likely (8 of 10, i.e., 80%).

Adolescent↗
PubMed1984

[Development of a standardized form for mercury gauge plethysmography of veins and arteries].

Mercury strain gauge plethysmography will play an increasingly important role in vascular function exploration, participating in the detection of deep vein thrombosis and replacing arteriopathy in its arterio-capillary context. This required the development of a standardized reporting form for entering results of venous and arterial examinations and providing simple, clear evaluations of vascular function to assist therapeutic decisions. A standardized sheet in the form of rapidly scanned graphs and tables was established, this simplified representation facilitating decision making. Wider use of this type of form is proposed, with the aim of providing uniformity of data from mercury strain gauge plethysmography and statistical and computerized analysis of results of multicentre studies.

Computers↗
PubMed1983

[Quantitative aortic flow and cardiac output volume determinations in rabbits using tetrapolar impedance plethysmography].

In 25 normal rabbits the transthoracic impedance changes were continually registered at rest and during pharmacological exercise by use of various types of electrodes. These changes were quantified by the formula of Kubicek for estimation of cardiac output. The obtained values were compared with the values of cardiac output and the flow in the aorta descendens measured by electromagnetic flowmetry in the aorta descendens. Linear regression analyses for several intervals of ejection and various types of electrodes showed a high and significant correlation between the values estimated by both methods (r greater than or equal to 0.96, p less than or equal to 0.001). The analyses of confidence intervals of the parameters of linear regression showed that the functional relations can be described by uniform parameters of regression. On this basis were estimated coefficients of correction which allow quantitative evaluation of the cardiac output and the flow in the aorta descendens in rabbits by use of tetrapolar impedance plethysmography. For cardiac output: (Formula: see text) for the flow in the aorta descendens: (Formula: see text) Tetrapolar impedance plethysmography is a noninvasive method, which allows quantitative and dynamic evaluation both of the cardiac output and the flow in the aorta descendens in rabbits.

Animals↗
PubMed1983

The value of combined strain gauge plethysmography and radioactive iodine fibrinogen scan of the leg in the diagnosis of deep vein thrombosis.

The fallibility of the clinical diagnosis of deep venous thrombosis has led to a variety of noninvasive diagnostic methods, for example, Doppler ultrasound, plethysmography, 125I fibrinogen and radionuclide phlebography. This study was undertaken to analyze the value of combined strain gauge plethysmography and 125I fibrinogen scan of the leg in the diagnosis of deep venous thrombosis. The study was carried out upon 368 patients with suggestive findings of venous thrombosis. Four hundred and fifty strain gauge plethysmograms were reviewed. Venograms were done upon 106 limbs and 125I fibrinogen leg scans, on 136 limbs. Of the 64 limbs with normal strain gauge plethysmograms which had venograms, 58 were normal, five had incompetent perforators and one limb had deep venous thrombosis. Of the 42 legs with abnormal strain gauge plethysmograms which had venograms, 25 had deep venous thrombosis, 15 had incompetent perforators and two were normal. Twenty-three of 24 legs having both abnormal strain gauge plethysmograms and leg scans were confirmed to have deep venous thrombosis at venography. Fourteen of 18 legs with abnormal strain gauge plethysmograms but normal scans were found to have incompetent perforators. We conclude, that the strain gauge plethysmogram is a reliable test in excluding deep venous thrombosis and, when combined with the fibrinogen leg scan, is reliable in its diagnosis.

Adolescent↗
PubMed1982

[Mercury gauge plethysmography. Sensitivity and specificity compared with standard phlebography (author's transl)].

Mercury strain gauge plethysmography with programme and ECG synchronous venous occlusion was tested in 14 normal subjects (28 lower limbs). The results obtained in the case of recent deep venous thrombosis of the lower limbs were compared with those of phlebography ni 39 patients: 26 proximal thromboses and 15 calf thromboses. Interpretation of the results must take into account the strict conditions under which the plethysmography was carried out: position of the subject and especially of the lower limbs and the technical characteristics of the apparatus used. Specificity was 96.4% for the group of normal subjects. Sensitivity calculated for all the cases of venous thrombosis studied was 97.5% whilst it was 100% for proximal thromboses (femoral and iliac).

Acute Disease↗
PubMed1981

[Plethysmography in phlebology].

A survey of the practical use of plethysmography for phlebological purposes is given. The most important applications for plethysmographic methods are: Screening for deep leg vein thrombosis with satisfactory accuracy in total proximal occlusions; estimation of capillary filtration rate (no clinical value); function of muscle pump, indication and control of therapy; quantitative arterial blood measurement; and determination of systolic blood pressure at the ankle level and in the toes. Today's most perfect method for practical use is strain gauge plethysmography.

Blood Pressure↗
PubMed1980

Reproducibility of strain gauge venous occlusion plethysmography in long-run measurements in man.

In order to evaluate strain gauge venous occlusion plethysmography as a tool to test the effects of treatment on peripheral blood flow, some biasing effects due to this technique were studied in relation to a long-run session and to cuff and gauge displacement. Arm peripheral blood flow was estimated by a computerized procedure during three successive days in a young male subject. The measurements were arranged as follows: 1) 75 replications under constant conditions, lasting 1.6 hours; 2) 18 triplets with alternative cuff displacement between two forearm positions, lasting 1.5 hours; 3) 40 measurements taken alternatively with a fixed gauge and a displaced one from a proximal to a distal position and vice versa, lasting 2.1 hours. Statistical comparison revealed: 1) a good long-run reproducibility during the first session; 2) a significant difference between the first and third day sessions under the same conditions; 3) a significant difference between the distal and proximal cuff mean flows during the second day session; 4 significant differences among the third day means in dependence of gauge position; 5) no significant dependence on strain gauge tension during the third day session. It is thus concluded that strain gauge plethysmography may be a reliable technique mainly in a longitudinal experimental design when the acute effect of some drug administration is to be evaluated.

Adult↗
PubMed1980

A comparison between the ankle systolic pressure and mercury strain gauge plethysmography in the assessment of patients with arterial disease of the lower limbs.

Mercury strain gauge plethysmography and ankle systolic pressure measurements have been used in the assessment of patients with arterial disease affecting the lower limbs. Plethysmography can differentiate those patients with arterial disease from normal subjects, but it is not possible to determine the site of arterial disease as judged angiographically. It is possible to differentiate patients with rest pain from those patients experiencing intermittent claudication by means of the time to peak flow and time to half peak flow. Because of the significant positive correlation between the changes in peak flow and pressure index produced by reconstructive arterial surgery, the plethysmograph has not been shown to have any advantage over ankle systolic pressure measurements in assessing the results of surgery for peripheral arterial disease affecting the lower limb.

Adult↗
PubMed1994

[From thrombosis to post-thrombotic syndrome--plethysmography studies of venous function].

46 patients with deep vein thrombosis have been investigated by strain gauge plethysmography and by foot-volumetry in the acute state, after 4 weeks, and after every year up to 5 years. The primary therapy consisted in anticoagulation, compression-bandages and walking exercises. Venous drainage measured by venous occlusion plethysmography showed in average a normalisation after one year, while expelled volume as a parameter for the venous pumping function (assessed by foot-volumetry) remained in the pathological range. Since the clinical outcome--ulceration in 6.5%, lipodermatosclerosis in 15% and no major signs in 78%--does not correspond to these functional findings it is concluded that venous refluxes which are the main cause for the impeded pumping function lead to skin changes only in specially predisposed cases.

Adult↗
PubMed1993

A rational approach to detection of significant reflux with duplex Doppler scanning and air plethysmography.

PURPOSE: Several techniques are currently available for the detection of venous reflux. We have attempted to determine the relative value and accuracy of available techniques to develop a logical strategy of investigation in reflux venous insufficiency. METHODS: The morphologic distribution of venous incompetence (erect duplex and descending venography); the results of ambulatory venous pressure measurement, venous refilling time, the Valsalva test, and air-plethysmography (venous refilling index, VFI); and the clinical severity were described in 118 consecutive limbs. In an attempt to validate the tests, results were correlated with the clinical severity classification (class 0, n = 34; class 1, n = 42; class 2, n = 11; class 3, n = 31) and with a standardized quantification of reflux (multisegment score) as seen on standing duplex Doppler scanning with rapid deflation cuffs. RESULTS: Twenty-nine percent of limbs with severe venous disease (class 2/3) had pure deep insufficiency, only 6% had pure superficial disease, and the remainder had a combination. A history of previous thrombosis and the presence of posterior tibial vein incompetence were markedly common with ulcer disease (84% and 42%, respectively). The duplex Doppler multisegment score correlated strongly with clinical severity classification (r = 0.97). The venous refilling time and VFI had the highest sensitivity in identifying severe venous disease (class 2/3), and the ambulatory venous pressure had excellent specificity. CONCLUSIONS: For noninvasive determination of reflux, the combination of VFI and duplex scanning not only localized reflux but also separated severe clinical vein disease from mild, with high sensitivity and specificity. Air plethysmography may also provide valuable information regarding calf muscle pump and outflow obstruction.

Diagnosis, Differential↗
PubMed1996

[Value of plethysmography in the respiratory function evaluation of coal miners in Lorraine].

The results of body plethysmography in 607 coalminers from Lorraine, France, are analysed. The relationship between radiological aspects and tobacco consumption are discussed. When progressive massive fibrosis (PMF) is absent, total lung capacity (TLC) and slow vital capacity (VC) are related with profusion, but remain independant of X-ray type and tobacco consumption. Tobacco alters flows and FEV1/VC results. A 20% incidence of residual volume (RV) inflation is observed unrelated to X-ray aspect. When PMF is present, TLC results are more contrasted (8.9% restrictive defects, 5.7% hyperinflation) and obstructive pattern follows X-ray progression. Tobacco consumption induces more RV and functional residual capacity inflation. These results strongly support the fact that the effects of dust exposure vary with smoking. Consequently, the interactions between pneumoconiotic fibrosis and distension appear to be reflected by plethysmography. This method is useful for determining each functional pattern. It may also be of pronostic value but this needs to be confirmed by further studies.

Aged↗
PubMed1997

A prospective follow-up study of acute deep venous thrombosis using colour duplex ultrasound, phlebography and venous occlusion plethysmography.

OBJECTIVE: To study the extent of deep venous thrombosis (DVT) and thrombus regression over time and to compare the results obtained with different diagnostic techniques. EXPERIMENTAL DESIGN: A prospective follow-up study with repeated examinations during a 6-month period. SETTING: Patients studied at clinical vascular laboratories. PATIENTS: Forty patients hospitalised for acute DVT. Thirty-six of these completed the follow-up period. MEASURES: The diagnosis of DVT was confirmed with phlebographic and/or ultrasonographic techniques. The patient were then re-examined with colour duplex ultrasound and venous occlusion plethysmography after one week, 3 months and 6 months and with phlebography after 1 week and 6 months. The extent of DVT and number of occluded segments were determined with phlebographic and ultrasonographic techniques. Venous occlusion plethysmography was used to evaluate the functional degree of outflow obstruction. RESULTS: Colour duplex scanning at 3 months' and 6 months' follow-up showed that 55% and 74% of initially occlusive thrombi, respectively, were recanalized, with thrombus resolution occurring faster and more completely in those initially limited to popliteal and/or calf level. Discrepancies between phlebography and duplex scanning were found in 6% (26/441) of venous segments investigated by both methods, primarily concerning flow in the veins below the knee. CONCLUSIONS: In comparison with phlebography, colour duplex scanning is an accurate method for evaluation and follow-up of patients with DVT. The non-invasive nature of colour duplex scanning makes this method extremely suitable for repeated studies and thus a potentially very valuable tool for both clinical and research studies of circulatory changes involved in acute and chronic DVT.

Adult↗
PubMed2000

Plethysmography: the new wave in haemodynamic monitoring--a review of clinical applications.

The plethysmograph, a useful, non-invasive circulatory assessment capability featured on most modern pulse oximeters, provides a waveform representation of pulsatile peripheral blood flow, from which can be drawn assessments of both the peripheral and central circulation. Implementation and maintenance of plethysmography monitoring is straightforward and uncomplicated by virtue of its non-invasiveness. Yet despite its capabilities, ease of use and widespread availability it remains an underutilised data source. Diagnostic and monitoring capabilities of the device include heart rate and rhythm monitoring, detection of myocardial and valvular dysfunction, assessment of intra-aortic balloon pump performance when pressure waveforms are unobtainable, detection and measurement of pulsus paradoxus, improved performance of the Allen's test and detection of peripheral vascular diseases, peripheral vasoconstriction and developing shock. This paper describes the range of established applications of plethysmography, reviews pertinent literature and describes the directions in which, in the absence of supportive literature, clinical practice is finding applications.

Cardiography, Impedance↗
PubMed1981

Venous volume displacement plethysmography: Its diagnostic value in deep venous thrombosis as determined by receiver operator characteristic curves.

The pitfall of several reviews of noninvasive venous assessment has been the expression of the test data solely in terms of diagnostic accuracy (the number of correct tests in ratio to all tests performed), where results of a test will vary according to disease prevalence. The advantages of receiver operator characteristic curve analysis are twofold: (1) it describes the dynamic relationship between sensitivity (the ratio of the number of true positive tests to the patients with deep venous thrombosis) and specificity (the ratio of true negative tests to the number of patients with no deep venous thrombosis) independent of disease prevalence; and (2) the threshold criteria that defines a positive test can be set by the best balance between sensitivity and specificity and then applied to a given patient population for its diagnostic accuracy. Venous volume plethysmography is a widely used, simple and rapid method. It was compared to the "gold standard" of phlebography in a prospective blind study of 70 limbs that were clinically suspect of having deep venous thrombosis (DVT). Venous volume displacement plethysmography was defined objectively by three quantitative parameters: (1) maximum venous outflow, (2) integer ratio, and (3) segmental venous capacitance ratio. The DVT (22 to 70 positive phlebograms) was divided by anatomic location into either calf vein DVT or proximal DVT (popliteal vein or above). By combining these three parameters, a balance between sensitivity and specificity was obtained to provide a rapid, objective method for screening patients with suspected DVT.

Journal Article↗
PubMed1999

Comparison of air-displacement plethysmography with hydrostatic weighing and bioelectrical impedance analysis for the assessment of body composition in healthy adults.

BACKGROUND: Over the past decade, considerable attention has been paid to accurately measuring body composition in diverse populations. Recently, the use of air-displacement plethysmography (AP) was proposed as an accurate, comfortable, and accessible method of body-composition analysis. OBJECTIVE: The purpose of this study was to compare measurements of percentage body fat (%BF) by AP and 2 other established techniques, hydrostatic weighing (HW) and bioelectrical impedance analysis (BIA), in adults. DESIGN: The sample consisted of healthy men (n = 23) and women (n = 24). %BF was measured by AP, HW, and BIA. RESULTS: In the total group, %BF(AP) (25.0+/-8.9%) was not significantly different from %BF(HW) (25.1+/-7.7%) or %BF(BIA) (23.9+/-7.7%), and %BF(AP) was significantly correlated with %BF(HW) (r = 0.944, P < 0.001) and with %BF(BIA) (r = 0.859, P < 0.01). Compared with HW, AP underestimated %BF in men (by -1.24+/-3.12%) but overestimated %BF in women (by 1.02+/-2.48%), indicating a significant sex effect (P < 0.05). The differences in estimation between AP and BIA and between BIA and HW were not significantly different between the sexes. CONCLUSION: AP is an accurate method for assessing body composition in healthy adults. Future studies should assess further the cause of the individual variations with this new method.

Adipose Tissue↗
PubMed2002

Effects of clothing on accuracy and reliability of air displacement plethysmography.

PURPOSE: The purpose of this investigation was to quantify the effects of different attire on the accuracy and reliability of estimating percent body fat (%fat) by using air displacement plethysmography (ADP). METHODS: Fifteen adults were tested four times on four separate occasions. Each session consisted of estimating %fat with ADP wearing a swimsuit (ADP(SS)), a hospital gown (ADP(HG)), and in the nude (ADP(N)), plus assessment by hydrostatic weighing (HW). RESULTS: An ANOVA revealed no significant differences within any of the four methods over the 4 days. Intraclass correlation coefficients revealed a strong relationship for repeated measures in ADP(SS) (r = 0.981), ADP(HG) (r = 0.993), ADP(N) (r = 0.989), and HW (r = 0.976). Mean data for each condition indicated a significant underestimation (P < 0.05) of %fat while wearing a hospital gown (13.8 +/- 7.7%) compared with ADP(SS) (22.0 +/- 7.8%), ADP(N) (23.5 +/- 7.5%), and HW (22.6 +/- 6.8%). CONCLUSION: Reliability of ADP does not appear to be compromised by clothing; however, wearing a hospital gown significantly affects accuracy, reducing %fat estimations by approximately 9% compared with the recommended swimsuit. Measurement in the nude does not provide more reliable or accurate measures than wearing a swimsuit.

Adolescent↗