Preventing hemodilution abolishes natriuresis of water immersion in humans.

Am J Physiol

Danish Aerospace Medical Centre of Research, Rigshospitalet 7805, DK-2200 Copenhagen, Denmark.

Published: September 1998

The hypothesis was tested that hemodilution is one of the determinants of the water immersion (WI)-induced natriuresis. Eight males were subjected to 3 h of 1) WI to the midchest (Chest), 2) WI to the neck combined with thigh cuff-induced (80 mmHg) venous stasis (Neck + stasis), and 3) a seated time control (n = 6). Central venous pressure and left atrial diameter increased to the same extent during Chest and Neck + stasis (P < 0.05), whereas renal sodium excretion only increased during Chest from 77 +/- 7 to 225 +/- 13 micromol/min (P < 0.05). During Chest, plasma colloid osmotic pressure (COP) decreased from 27.7 +/- 0.7 to 25.1 +/- 0.7 mmHg (P < 0.05), and plasma volume (PV) increased from 3,263 +/- 129 to 3,581 +/- 159 ml (P < 0.05), whereas these variables remained unchanged during Neck + stasis. Plasma norepinephrine concentration decreased similarly during Chest and Neck + stasis by 45 +/- 7 and 34 +/- 4%, respectively (P < 0.05), whereas plasma renin activity decreased only during Chest (P < 0.05). In conclusion, during WI in humans 1) hemodilution (decrease in COP and increase in PV) is a pivotal stimulus for the natriuresis and 2) central blood volume expansion without hemodilution does not augment renal sodium output.

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajpregu.1998.275.3.R879DOI Listing

Publication Analysis

Top Keywords

neck stasis
16
chest neck
12
water immersion
8
renal sodium
8
+/-
8
005 plasma
8
decreased chest
8
chest
6
005
6
neck
5

Similar Publications

Background And Purpose: This animal study was designed to evaluate in vivo the acute and short-term safety and efficacy of the new Artisse intrasaccular device (ISD) for aneurysm occlusion and to gain knowledge about the behavior in the aneurysms.

Materials And Methods: The device was implanted in 7 white New Zealand rabbits with bifurcation aneurysms. Immediate and 90-day angiographic follow-up as well as histologic and scanning electron microscope imaging were evaluated.

View Article and Find Full Text PDF

Background: Anticoagulants increase the risk of cardiac tamponade in patients with pericardial effusion (PE). Therefore, inappropriate administration of them in the presence of PE can lead to a catastrophic outcome. This study presents a patient with a provisional misdiagnosis of venous thromboembolism (VTE).

View Article and Find Full Text PDF

Background And Purpose: This study evaluates the early clinical performance of the new Artisse Intrasaccular Device (Artisse ISD), a self-expandable intrasaccular flow diverter, for treating wide-necked aneurysms (WNAs). We report initial safety and efficacy outcomes in the first cohort of patients treated with this novel device.

Methods: Prospective clinical and radiological data were collected for all patients treated with the Artisse ISD at three Austrian neurovascular centers from July 2023 to August 2024.

View Article and Find Full Text PDF

Improving Diagnosis of Acute Cholecystitis with US: New Paradigms.

Radiographics

December 2024

From the Departments of Radiology (R.P., J.R.T., L.S., A.K.) and Pathology (D.B.B.), Stanford University, 300 Pasteur Dr, Palo Alto, CA 94304.

Acute cholecystitis is an inflammatory condition of the gallbladder typically incited by mechanical obstruction. Accurate diagnosis of this common clinical condition is challenging due to variable imaging appearances as well as overlapping clinical manifestations with biliary colic, acute hepatitis, pancreatitis, and cholangiopathies. In acute cholecystitis, increased dilatation and high intraluminal pressures lead to gallbladder inflammation and may progress to gangrenous changes, focal wall necrosis, and subsequent perforation.

View Article and Find Full Text PDF

Hemodynamic analysis of a thrombosed bleb in an unruptured cerebral aneurysm.

Surg Neurol Int

October 2024

Department of Neurological Surgery, Ryofukai Satoh Neurosurgical Hospital, Fukuyama, Japan.

Article Synopsis
  • This study focuses on a rare case of a bleb in an unruptured cerebral aneurysm that underwent complete thrombosis over 7 years, which has not been documented before.
  • The use of computational fluid dynamics (CFD) analysis revealed that factors like decreased flow rate and changes in wall shear stress were linked to the thrombosis in the bleb.
  • The findings highlight the importance of CFD in understanding the hemodynamics related to thrombosis in cerebral aneurysms, potentially improving clinical interventions.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!