Clinical physiology and functional imaging
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Clin Physiol Funct Imaging · Jul 2018
Effect of spontaneous saliva swallowing on short-term heart rate variability (HRV) and reliability of HRV analysis.
The effects of effortful swallowing and solid meal ingestions on heart rate variability (HRV) have been examined previously. The effects of spontaneous saliva swallowing on short-term HRV and reliability of HRV analysis have not been studied before. The effect of saliva swallowing on HRV analyses parameters [meanRRI, SDNN (standard deviation of normal-to-normal), LF (low frequency), HF (high frequency) powers, LH/HF] and the reliability of LF and HF powers were investigated by frequency, time-frequency and intraclass correlation coefficient (ICC) analyses. ⋯ When the analyses were made for 2-min signal periods, these values decreased to 0·63 and 0·67. We concluded that spontaneous saliva swallowing can change HRV parameters. We have also seen that changes in swallowing rate and use of short signal segments may reduce the reliability of HRV analyses.
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Clin Physiol Funct Imaging · May 2018
Comparative Study Observational StudyComparison of cardiac output estimates by bioreactance and inert gas rebreathing methods during cardiopulmonary exercise testing.
This study assessed the agreement between cardiac output estimated by inert gas rebreathing and bioreactance methods at rest and during exercise. ⋯ Bioreactance and inert gas rebreathing methods show acceptable levels of agreement for estimating cardiac output at higher levels of metabolic demand. However, they cannot be used interchangeably due to strong disparity in results at rest and low-to-moderate exercise intensity.
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Clin Physiol Funct Imaging · Mar 2018
Comparative StudyDiscriminatory ability of right atrial volumes with two- and three-dimensional echocardiography to detect elevated right atrial pressure in pulmonary hypertension.
Pulmonary hypertension (PH) patients have high mortality due to right ventricular failure. Predictors of poor prognostic outcome are increased right atrial volume (RAV) and elevated mean right atrial pressure (mRAP). Our aim was to determine whether RAV measured with 2D echocardiography (2DE) and 3D echocardiography (3DE) can detect elevated mRAP in patients evaluated for PH. ⋯ Enlarged RA measures with 2DE and 3DE have better discriminatory ability compared with IVC measures, to detect elevated mRAP in patients evaluated for PH.
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Clin Physiol Funct Imaging · Mar 2018
Oesophageal Doppler guided optimization of cardiac output does not increase visceral microvascular blood flow in healthy volunteers.
Oesophageal Doppler monitoring (ODM) is used clinically to optimize cardiac output (CO) and guide fluid therapy. Despite limited experimental evidence, it is assumed that increasing CO increases visceral microvascular blood flow (MBF). We used contrast-enhanced ultrasound (CEUS) to assess whether ODM-guided optimization of CO altered MBF. ⋯ ODM-optimized CO reduces time to renal perfusion but does not alter renal or hepatic MBF. A lack of relationship between microvascular visceral perfusion and CO following ODM-guided optimization may explain the absence of improved clinical outcome with ODM monitoring.
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Clin Physiol Funct Imaging · Jan 2018
The multi-ethnic global lung initiative 2012 and Third National Health and Nutrition Examination Survey reference values do not reflect spirometric measurements in Black boys and men from Tanzania.
The interpretation of spirometric results of Black Africans according to reference standards based on data from outside their native environment may lead to the wrong conclusions. This article aims to characterize the ventilatory capacity of boys and men from Tanzania according to forced expiratory volume in one second (FEV1 ), forced vital capacity (FVC), peak expiratory flow (PEF) and FEV1 /FVC based on the collected anthropological material and to compare them to NHANES III, Third National Health and Nutrition Examination Survey (NHANES III) African American predicted values and GLI2012 equations. The analysis included spirometric measurements of n = 295 participants from Tanzania. ⋯ All the spirometric measurements included in the analysis were statistically significantly correlated with age, body height, sitting height, trunk length and body weight. The application of prediction formulae developed for non-African populations overestimates the values for Black Africans. The results of spirometric measurements are ecosensitive and dependent on various external (environmental) factors.