orthostasis


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Related to orthostasis: succussion splash, orthostatic hypertension

orthostasis

[-stā′sis]
maintenance of an upright standing posture. In some medical tests a patient may need to maintain orthostasis for a long period to stimulate a rise in aldosterone concentration.
References in periodicals archive ?
The aim of this study was to find differences in the autonomic regulation of the heart at the rest and during orthostasis between children with attention deficit/ hyperactivity disorder and healthy subjects using short-term heart rate variability analysis.
Plasma neurotransmitters, blood pressure and heart rate during supine-resting, orthostasis, and moderate exercise conditions in two types of hypertensive patients.
The observation of orthostasis, as evidenced clinically as patient complaints of "light-headedness," dizziness, fainting or acute weakness, should signal the need for increased vigilance.
Supine-resting plus orthostasis plus exercise test showed raised values of NA that increased after both types of challenges: 465 pg/mL, 538 pg/mL, and 987 pg/mL, respectively.
The patient's blood pressure was 135/75 mm Hg without orthostasis.
Increase of mean arterial pressure as compared to the orthostasis test before medication was on average 4.
Multiple factors that might increase the pharmacodynamic response to SAPHRIS, causing poorer tolerance or orthostasis,could be present in elderly patients, and these patients should be monitored carefully.
In all patients with either TAH or LVAD, device rate, flow and volume, blood pressure, oxygen saturation, and symptoms of orthostasis and exercise intolerance [rating of perceived exertion (RPE)] should be monitored throughout each treatment session.
Cardiovascular and blood pressure related side effects, including dizziness and orthostasis, were low in both trials.
This research was possible because the neurochemical laboratory at the Instituto de Medicina Experimental, Faculty of Medicine at the Universidad Central de Venezuela has the capability to assess all circulating neurotransmitters, and this is where those parameters were routinely tested before and after the administration of many neuropharmacologic agents, (2-7) as well as during supine-resting plus orthostasis plus exercise and several pharmacologic challenges.
Physical examination revealed an afebrile, pale, cachectic man with moderate dehydration and orthostasis.