VALIDATION OF THE SUPINE VENOUS PUMP FUNCTION-TEST - A NEW NONINVASIVE TOOL IN THE ASSESSMENT OF DEEP VENOUS INSUFFICIENCY

1. A new non-invasive test was developed to assess calf muscle pump fu nction: the supine venous pump function test, The technique uses strai n-gauge plethysmography and is performed in the supine position. The m ethod is superior to other non-invasive methods because basically the most essential haemodynamic parameter, venous pressure decrease, is us ed by properly converting venous volume measurements into venous press ure, The validity of this test was established by comparison with inva sive venous pressure measurements and by determining the reproducibili ty. Additionally, normal values were determined. 2. In 28 extremities the supine venous pump function test was performed simultaneously with invasive venous pressure measurements, The reproducibility of the tes t was assessed in 10 randomly chosen volunteers, In 34 volunteers norm al values were obtained and 26 patients with clinical venous insuffici ency were examined. 3. Comparison of the two methods revealed a correl ation coefficient of r=0.98 (P<0.001). A mean difference of 3.9%(pf) b etween both methods was found with limits of agreement of -6.3%(pf) to 14.1%(pf). The coefficient of repeatability was 13%(pf) and the coeff icient of variation was 9%. The normal range was found to be >60%(pf). The mean pump function in the patient group was 45%(pf). 4. The limit s of agreement are small enough to be confident that the supine venous pump function test can be used instead of invasive venous pressure me asurements to assess calf muscle pump function in clinical practice, T he reproducibility of the test is good.