Search results for "Plethysmograph"
showing 10 items of 94 documents
Changes of arterial hemodynamics in patients with type 2 diabetes mellitus or impaired glucose tolerance
2006
Aim: The aim of our study was to evaluate the arterial hemodynamics in patients with type 2 diabetes mellitus or impaired glucose tolerance without clinical or Doppler evidence of peripheral arterial disease, in order to early detect vascular damage. Methods. We studied 20 subjects (12 men and 8 women, aged between 48 and 62 years) with type 2 diabetes mellitus (Group 1), 20 subjects (11 men and 9 women, aged between 49 and 61 years) with reduced glucose tolerance (Group 2), and 20 normal subjects (10 men and 10 women, aged between 48 and 62 years) (Group 3). Each subject underwent strain-gauge plethysmography and the following parameters were evaluated: rest flow (RF); peak flow (PF); PF/R…
Prevalence and Risk Factors of PAD among Patients with Elevated ABI
2008
ObjectivesTo assess the prevalence and clinical significance of elevated ankle-brachial index (ABI) in patients referred to vascular consultation.DesignRetrospective clinical study.Material and methodsIn 1,762 patients referred with a suspicion of peripheral arterial disease (PAD), ABI and toe brachial index (TBI) were measured by photoplethysmography. ABI≥1.3 was considered falsely elevated and TBI<0.60 was the diagnostic criterion for PAD.ResultsThe prevalence of elevated ABI was 8.4% and that of PAD among these patients 62.2%. PAD was significantly more prevalent among subjects with severe symptoms (rest pain, ulcers or gangrene) than in those with intermittent claudication (83.8% and 45…
Extended Granger causality: a new tool to identify the structure of physiological networks.
2015
Granger causality (GC) is a very popular tool for assessing the presence of directional interactions between two time series of a multivariate data set. In its original formulation, GC does not account for zero-lag correlations possibly existing between the observed time series. In the present study we compare the GC with a novel measure, termed extended GC (eGC), able to capture instantaneous causal relationships. We present a two-step procedure for the practical estimation of eGC based on first detecting the existence of zero-lag correlations, and then assigning them to one of the two possible causal directions using pairwise measures of non-Gaussianity. The proposed method was validated …
Associations of fat mass and fat-free mass with physical fitness in 4-year-old children: Results from the MINISTOP trial
2016
Physical fitness is a powerful marker of health in youth. Studies in adolescents and adults suggest that higher fat mass is related to worse physical fitness. However, there is limited knowledge whether fat mass and fat-free mass are associated with physical fitness already in preschoolers. Baseline data from the MINISTOP (Mobile-based INtervention Intended to STop Obesity in Preschoolers) trial was utilized for this cross-sectional analysis. Body composition was assessed using air-displacement plethysmography. Fat mass index [fat mass (kg)/height(2) (m)] and fat-free mass index [fat-free mass (kg)/height(2) (m)] were used to provide height-adjusted measures of body composition. Physical fi…
Noradrenaline depleting and blood pressure lowering activity of threo-corbadrine
1968
Abstract Threo-corbadrine caused a long-lasting depletion of noradrenaline in the heart and in mesenteric vessels and lowered the blood pressure of normal and renal hypertensive rats. It is suggested that threo-cobadrine decreases vascular tone by acting peripherally as a substitute adrenergic transmitter.
Measurement of phase I volume breath by breath in spontaneously breathing guinea pigs.
1990
A new method to determine phase I volume in tracheotomized spontaneously breathing guinea pigs is presented. Measurements were performed in three animals weighing 567-896 g. In simultaneous tracings of tidal volume (VT) and expiratory profiles of endogenous gases (PO2 or PCO2), the phase I volume of each breath was determined graphically as the volume expired up to the end of phase I of the expirogram. The mean phase I volume of different animals ranged from 0.29 to 0.43 ml with an arithmetic dispersion between 0.014 and 0.021 ml. Spontaneous sighs sometimes with doubling of the VT caused a significant rise of phase I volume up to 50% of the normal values. The linear regression curve was c…
Classic conditioning of the ventilatory responses in rats
1997
Nsegbe, Elise, Guy Vardon, Pierre Perruchet, and Jorge Gallego. Classic conditioning of the ventilatory responses in rats. J. Appl. Physiol. 83(4): 1174–1183, 1997.—Recent authors have stressed the role of conditioning in the control of breathing, but experimental evidence of this role is still sparse and contradictory. To establish that classic conditioning of the ventilatory responses can occur in rats, we performed a controlled experiment in which a 1-min tone [conditioned stimulus (CS)] was paired with a hypercapnic stimulus [8.5% CO2, unconditioned stimulus (US)]. The experimental group ( n = 9) received five paired CS-US presentations, followed by one CS alone to test conditioning. Th…
Use of a portable device to record maximum inspiratory flow in relation to dyspnoea in patients with COPD
2011
SummaryForced inspiratory measures have been described to reflect the reduction in dyspnoea upon bronchodilation in severe COPD. Based on this we evaluated the applicability and usefulness of a portable device for the assessment of forced inspiration. In 37 patients with COPD (GOLD II/II/IV n = 16/15/6, mean ± SD FEV1 46.2 ± 15.4%pred) lung function was recorded prior to inhalation of 24 μg formoterol and 30 min later. Assessments comprised spirometry including forced inspiration, body plethysmography, maximum inspiratory flow (InCheck, Clement Clarke), and changes in dyspnoea via visual analogue scale (VAS). The sequence was repeated on a second day to assess reproducibility. Bronchodilati…
Changes in estimating echocardiography pulmonary capillary wedge pressure after hypersaline plus furosemide versus furosemide alone in decompensated …
2011
BACKGROUND: The aim of the study was to verify the effects of hypertonic saline solution (HSS) plus a high furosemide dose and light restriction of sodium intake compared with a high-dose infusion of furosemide alone on pulmonary capillary wedge pressure (PCWP), as determined by Doppler echocardiography and tissue Doppler imaging in patients suffering from decompensated heart failure. METHODS AND RESULTS: Consecutive patients in New York Heart Association functional class IV, unresponsive to oral high doses of furosemide up to 250-500 mg/d and/or combinations of diuretics, with ejection fraction <40%, serum creatinine <2 mg/dL, blood urea nitrogen ≤60 mg/dL, reduced urinary volume (<500 mL/…
Comparison of short-term heart rate variability indexes evaluated through electrocardiographic and continuous blood pressure monitoring
2019
Heart rate variability (HRV) analysis represents an important tool for the characterization of complex cardiovascular control. HRV indexes are usually calculated from electrocardiographic (ECG) recordings after measuring the time duration between consecutive R peaks, and this is considered the gold standard. An alternative method consists of assessing the pulse rate variability (PRV) from signals acquired through photoplethysmography, a technique also employed for the continuous noninvasive monitoring of blood pressure. In this work, we carry out a thorough analysis and comparison of short-term variability indexes computed from HRV time series obtained from the ECG and from PRV time series …