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de Jong-de Vos Van Steenwijk, C.C.E. (author), Wieling, W. (author), Harms, M.P.M. (author), Wesseling, K.H. (author), TNO Biomedical Instrumentation (author)
1. Fainting is a common phenomenon in young subjects, but the final events before the actual faint are not well known. The aim of the present study was to study the inter-individual variability of haemodynamic events associated with near-fainting in children and teenagers. 2. Sixty-eight healthy subjects (aged 6-16 years) performed a 70°tilt-up...
article 1997
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Wesseling, K.H. (author), Technisch Physische Dienst TNO - TH (author)
article 1992
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Omboni, S. (author), Parati, G. (author), Castiglioni, P. (author), di Rienzo, M. (author), Imholz, B.P.M. (author), Langewouters, G.J. (author), Wesseling, K.H. (author), Mancia, G. (author), TNO Biomedical Instrumentation (author)
Portapres is a noninvasive, beat-to-beat finger blood pressure (BP) monitor that has been shown to accurately estimate 24-hour intra-arterial BP at normal and high BPs. However, no information is available on the ability of this device to accurately track ambulatory BP variability. In 20 ambulatory normotensive and hypertensive subjects, we...
article 1998
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Gizdulich, P. (author), Wesseling, K.H. (author), TNO Biomedical Instrumentation (author)
Pressure-volume (p-V) relationships of a segment of the forearm circulation have been measured in nine male healthy subjects. Forearm volume was measured using electrical impedance plethysmography, arterial transmural pressure by subtracting mean arterial pressure measured contralaterally in a finger from the pressure in a cuff placed over the...
article 1988
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Snelder, M. (author), Wesseling, B. (author), van Arem, B. (author), Hertogh, M.J.C.M. (author)
When infrastructures projects are evaluated, it is not only important to evaluate them with models that represent the average daily situation, but also to evaluate them in case of irregular situations like incidents. This becomes especially relevant when various project alternatives are expected to show significantly different scores in case of...
article 2017
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Langewouters, G.J. (author), Settels, J.J. (author), Roelandt, R. (author), Wesseling, K.H. (author), Technisch Physische Dienst TNO - TH (author)
In the clinic, blood pressure is measured almost exclusively using non- invasive intermittent techniques, of which the auscultatory (Riva- Rocci/Korotkoff, RRK) and the computerized oscillometric method are most often used. However, both methods only provide a momentary value. In addition, the accuracy is hampered by phenomena such as cuff...
article 1998
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Wesseling, K.H. (author), TNO Biomedische Instrumentatie (author)
Twenty-one years ago, in 1967, lecturer dr, Jan Peñáz submitted a patent description of a method to measure indirectly the full arterial pressure waveform in a finger using a volume clamp technique, and at the lOth Conference on Medical and Biological Engineering at Dresden in 1973, he actually demonstrated a device and published a one-page...
article 1990
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Atkins, N. (author), O' Brien, E. (author), Wesseling, K.H. (author), Guelen, I. (author), TNO Biomedical Instrumentation (author)
The most fallible component of blood pressure measurement is the human observer. The traditional technique of measuring blood pressure does not allow the result of the measurement to be checked by independent observers, thereby leaving the method open to bias. In the Sphygmocorder, several components used to measure blood pressure have been...
article 1997
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van Lieshout, J.J. (author), Toska, K. (author), van Lieshout, E.J. (author), Eriksen, M. (author), Walløe, L. (author), Wesseling, K.H. (author), TNO Biomedical Instrumentation (author)
The proper understanding of the cardiovascular mechanisms involved in complaints of short-lasting dizziness and the evaluation of unexplained recurrent syncope requires continuous monitoring of cardiac stroke volume (SV) in addition to blood pressure and heart rate. The primary aim of the present study was to evaluate a pulse wave analysis...
article 2003
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Gisolf, J. (author), Westerhof, B.E. (author), van Dijk, N. (author), Wesseling, K.H. (author), Wieling, W. (author), Karemaker, J.M. (author), TNO Industrie (author)
Objectives We set out to determine the effect of sublingual nitroglycerin (NTG), as used during routine tilt testing in patients with unexplained syncope, on hemodynamic characteristics and baroreflex control of heart rate (HR) and systemic vascular resistance (SVR). Background Nitroglycerin is used in tilt testing to elicit a vasovagal response...
article 2004
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Guelen, I. (author), Westerhof, B.E. (author), van der Sar, G.L. (author), van Montfrans, G.A. (author), Kiemeneij, F. (author), Wesseling, K.H. (author), Bos, W.J.W. (author), Gaubius Instituut TNO (author)
Objective: To evaluate three methods aimed at the reconstruction of brachial pressure from non-invasive finger arterial pressure measurements as implemented in the Finometer™, (FMS, Finapres Measurement Systems, Arnhem, Netherlands), the successor to the Finapres™ (TNO Siomedical Instrumentation, Amsterdam, Netherlands). Methods: Finger arterial...
article 2003
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Castiglioni, P. (author), Parati, G. (author), Omboni, S. (author), Mancia, G. (author), Imholz, B.P.M. (author), Wesseling, K.H. (author), di Rienzo, M. (author), TNO Biomedical Instrumentation (author)
The present study compares the spectral characteristics of 24-h blood pressure variability estimated invasively at the brachial artery level with those estimated by measurement of blood pressure at the finger artery using the non-invasive Portapres device. Broad-band spectra (from 3 x 10<sup>-5</sup> to 0.5 Hz) were derived from both finger and...
article 1999
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Gizdulich, P. (author), Imholz, B.P.M. (author), van den Meiracker, A.H. (author), Parati, G. (author), Wesseling, K.H. (author), TNO Biomedical Instrumentation (author)
Objective. Arterial pressure waveforms distort between brachial and finger arteries, causing differences mainly in systolic pressure. Distortion, reportedly, can be removed by applying a waveform filter to the finger pressure. Design. We analysed the data from two studies that detected discrepancies in systolic tracking between Finapres and...
article 1996
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Jellema, W.T. (author), Imholz, B.P.M. (author), van Goudoever, J. (author), Wesseling, K.H. (author), van Lieshout, J.J. (author), Technisch Physische Dienst TNO - TH (author)
1. The aims of this study were to determine the clinical feasibility of continuous, non-invasive Finapres recordings as a replacement for intrabrachial pressure during a 30 min head-up tilt, and the reliability of continuous cardiac output computation by pulse contour analysis from the finger arterial versus the brachial waveform. 2. In eight...
article 1996
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Schaap, M. (author), Wichink Kruit, R.J. (author), Manders, A.M.M. (author), Kamphuis, V. (author), Hoogerbrugge, R. (author), Nguyen, L. (author), Wesseling, J. (author), Weijers, E. (author)
Verbeterde metingen en een verbeterd model zijn gebruikt om een meer betrouwbare schatting van de zeezoutconcentraties in PM10 te maken. Als gevolg hiervan gaat de zeezoutaftrek naar beneden voor zowel de jaargemiddelde concentratie als het aantal overschrijdingsdagen
article 2012
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Jansen, J.R.C. (author), Schreuder, J.J. (author), Settels, J.J. (author), Kornet, L. (author), Penn, O.C.K.M. (author), Mulder, P.G.H. (author), Versprille, A. (author), Wesseling, K.H. (author), TNO Biomedical Instrumentation (author)
Application of the Stewart-Hamilton equation in the thermodilution technique requires flow to be constant. In patients in whom ventilation of the lungs is controlled, flow modulations may occur leading to large errors in the estimation of mean cardiac output. Methods: To eliminate these errors, a modified equation was developed. The resulting...
article 1996
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van Lieshout, J.J. (author), Imholz, B.P.M. (author), Wesseling, K.H. (author), Speelman, J.D. (author), Wieling, W. (author), TNO Biomedical Instrumentation (author)
Cardiovascular autonomic control was studied in a patient with an incomplete high spinal cord lesion who presented with the symptoms of severe dizziness during debating and singing but not during orthostasis. The marked falls in blood pressure upon singing and orthostasis (45° passive head-up tilt) were comparable in magnitude but different in...
article 1991
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Jellema, W.T. (author), Imholz, B.P.M. (author), Oosting, H. (author), Wesseling, K.H. (author), van Lieshout, J.J. (author), TNO Biomedical Instrumentation (author)
Objective: The aim of this study was to compare beat-to-beat changes in stroke volume (SV) estimated by two different pressure wave analysis techniques during orthostatic stress testing: pulse contour analysis and Modelflow, ie, simulation of a three-element model of aortic input impedance. Methods: A reduction in SV was introduced in eight...
article 1999
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Sprangers, R.L.H. (author), Wesseling, K.H. (author), Imholz, A.L.T. (author), Imholz, B.P.M. (author), Wieling, W. (author), Technisch Physische Dienst TNO - TH (author)
article 1991
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de Jong-de Vos Van Steenwijk, C.C.E. (author), Imholz, B.P.M. (author), Wesseling, K.H. (author), Wieling, W. (author), TNO Biomedical Instrumentation (author)
The objective of this study was to determine whether the Valsalva manoeuvre is applicable as a test for neurocardiovascular control in healthy children and teenagers. Sixty-eight 6- to 16-year-old children and teenagers performed two Valsalva manoeuvres in the sitting position. They were instructed to maintain airway pressure (strain) for 15 s...
article 1997
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