Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 2407456

Overnight decrease in hematocrit after nasal CPAP treatment in patients with OSA.

J Krieger·E Sforza·M Barthelmebs·J L Imbs·D Kurtz
View original source ↗Export metadata ↓

Abstract

To clarify the paradox of a decrease in urine and sodium excretion occurring along with the elimination of peripheral edema when patients with obstructive sleep apnea (OSA) are treated with nasal continuous positive airway pressure (CPAP), we investigated the immediate effects of this treatment on the hematocrit and red blood cell count in eight patients with OSA. The hematocrit decreased in all patients, from a mean of 45.6 +/- 1.2 percent to 43.0 +/- 1.4 percent, with a parallel decrease in the red blood cell count from 4.777 +/- 0.168 millions/cu mm to 4.577 +/- 0.174 millions/cu mm (p less than 0.0005, one-tailed, in both cases). These results suggest that nasal CPAP treatment causes a hemodilution in patients with OSA, and are compatible with the hypothesis of an atrial natriuretic peptide-induced fluid shift from the intravascular to the extravascular volume in untreated patients with OSA. The reversal of these changes with CPAP treatment could explain the simultaneous decrease in sodium and urine excretion and the reduction of peripheral edema.

Explore related subjects

DarknessErythrocyte CountHematocritHumansMaleMiddle AgedPositive-Pressure RespirationSleep Apnea SyndromesJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J Krieger, E Sforza, M Barthelmebs, J L Imbs, D Kurtz. 1990. Overnight decrease in hematocrit after nasal CPAP treatment in patients with OSA.. https://doi.org/10.1378/chest.97.3.729

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1995

Independent neural mechanisms for bright and dark information in binocular stereopsis.

Early visual processing is organized into a number of independent channels. In the retina, increments and decrements of brightness are processed independently by different groups of neurons. For psychophysical measurements of human vision, independence can be tested statistically. Using this criterion in a depth judgement task, we show here that, for binocular stereo vision, increments and decrements are treated independently, at least as far as the level at which information from the left and right eyes is first combined. At later stages of stereo processing, the information from the two channels is no longer independent. Because the signals for stereo vision are first combined at the visual cortex, these results suggest that the neural 'on' and 'off' channels remain independent right up to early cortical stages. Theoretical studies of stereo vision have proposed that visual features in the views of the two eyes are matched on the basis of 'similarity'. Our results show that stereo matching treats features as statistically independent (and therefore dissimilar) if they appear perceptually bright and dark relative to the background. If features differ perceptually but only in the degree of brightness or darkness, human stereo vision treats them as similar.

Darkness↗
PubMed1995

Induction of protein oxidation in human low density lipoprotein by the photosensitive organic hydroperoxide, N,N'-bis(2-hydroxyperoxy-2-methoxyethyl)-1,4,5,8-naphthalene-tetra-carb oxylic- diimide.

We have developed a new molecular probe, N,N'-bis(2-hydroxyperoxy-2-methyoxyethyl)-1,4,5,8-naphthalen e-tetra-carboxylic- diimide (NP-III), that specifically generates hydroxyl radical upon irradiation with longer wavelength ultraviolet light (UVA). Hydroxyl radicals are generated only upon irradiation, thus NP-III is a new controllable hydroxyl radical source. Apolipoprotein (apo-B) of human low density lipoprotein (LDL), and bovine serum alubumin (BSA), were irradiated with UVA in the presence of NP-III and their oxidation was evaluated by two independent methods: assay of protein carbonyl groups and gel electrophoresis. NP-III oxidized apo-B and BSA in a time- and concentration-dependent manner. The results demonstrate that NP-III is a controllable, precise, and potentially tagetable source of hydroxyl radicals with which to induce protein oxidation.

Darkness↗
PubMed1995

Apollo MEED mycology revisited and reviewed, including the Trichophyton terrestre keratinophilic growth at splashdown and 23 years after exposure to space parameters.

Keratinophilic Trichophyton terrestre conidia were exposed to selected parameters of space flight including 254, 280 and 300 nm UV light, full light and total darkness of space. Phenotypic isolates were grown on human hair collected from one source at years 1 and 23 after splashdown. The patterns of fungal growth on the hair, and the hair deterioration rates, were noted according to the space exposure. Growth and deterioration were consistent but slightly reduced at year 23.

Darkness↗