Hemodynamic measurements in human subjects and in experimental animals are generally made in the supine position; not much attention is paid to potential beneficial or harmful effects of right or left lateral positions on cardiac output or other hemodynamic variables. To evaluate the potential influence of such positional changes on cardiac performance, we measured cardiac output and left and r...

Neurogenic orthostatic hypotension and supine hypertension are common manifestations of cardiovascular dysautonomia in Parkinson's disease and related synucleinopathies. Because these disorders are haemodynamic opposites, improvement in one might be achieved at the expense of worsening of the other. Thus, management decisions necessitate assessment of the individual risks for patients with coex...

Baseline airway geometry is thought to be an important determinant of the airway response to challenge; this geometry is altered by changing posture. The effect of changes in posture on airway calibre, midtidal lung volume, and the airway response to inhaled histamine was studied in eight healthy subjects (four female; mean (SD) age 29.8 (5.1) years, FEV1 3.54 (0.65) 1). Each subject was studie...

 ABSTRACT Study design: A cross-sectional non-experimental study. Objectives: To collectively detect the reliability and feasibility of the five types of clinical tests that have been used to measure endurance of the trunk muscles in subjects with and without low back pain (LBP) and identifY the sensitivity of each test to predict the probability of the occurrence ofLBP. Background: Testing spi...

conclusion our findings support prone positioning for premature infants. therefore, it is advisable to nicu staff that if there is no obstacle for changing the infant’s position, prone position in infants with respiratory complications during receiving n-cpap in nicu can be useful. regarding the fact that prone position is a risk factor for sudden infant death syndrome , prone position should b...

This study looked at the effects of posture on the morning/evening expiratory flows and airway responsiveness to methacholine. Fourteen nonsmoking subjects with stable asthma (eight men, six women) were included in the study. Subjects were randomly allocated to spend 4 h in the supine or seated position on separate days, in the morning from 8 to 12 AM and in the evening from 8 to 12 PM. The FEV...

BACKGROUND Approximately 50% of patients with primary autonomic failure have supine hypertension. We investigated whether this supine hypertension could be driven by residual sympathetic activity. METHODS AND RESULTS In patients with multiple system atrophy (MSA) or pure autonomic failure (PAF), we studied the effect of oral yohimbine on seated systolic blood pressure (SBP), the effect of gan...

BACKGROUND It is well known that upper airway resistance increases with postural change from a sitting to supine position in patients with obstructive sleep apnoea (OSA). It is not known, however, how the postural change affects the ventilatory and occlusion pressure response to hypercapnia in patients with OSA when awake. METHODS The responses of minute ventilation (VE) and mouth pressure 0....

We evaluated the effect of prone positioning on gas-transfer characteristics in normal human subjects. Single-breath (SB) and rebreathing (RB) maneuvers were employed to assess carbon monoxide diffusing capacity (DlCO), its components related to capillary blood volume (Vc) and membrane diffusing capacity (Dm), pulmonary tissue volume (Vti), and cardiac output (Qc). Alveolar volume (Va) was sign...