The decrease of cardiac chamber volumes and output during positive-pressure ventilation

Positive-pressure ventilation (PPV) is widely used for treatment of acute cardiorespiratory failure, occasionally at the expense of compromised cardiac function and arterial blood pressure. The explanation why has largely rested on interpretation of intracardiac pressure changes. We evaluated the effect of PPV on the central circulation by studying cardiac chamber volumes with cardiac magnetic resonance imaging (CMR). We hypothesized that PPV lowers cardiac output (CO) mainly via the Frank-Starling relationship. In 18 healthy volunteers, cardiac chamber volumes and flow in aorta and the pulmonary artery were measured by CMR during PPV levels of 0, 10, and 20 cmH2O applied via a respirator and a face mask. All cardiac chamber volumes decreased in proportion to the level of PPV. Following 20-cmH2O PPV, the total diastolic and systolic cardiac volumes (±SE) decreased from 605 (±29) ml to 446 (±29) ml (P
Source: AJP: Heart and Circulatory Physiology - Category: Cardiology Authors: Tags: MUSCLE MECHANICS AND VENTRICULAR FUNCTION Source Type: research

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Source: European Radiology - Category: Radiology Source Type: research
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Source: Acta Neurologica Belgica - Category: Neurology Source Type: research
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Source: The International Journal of Cardiovascular Imaging - Category: Radiology Source Type: research
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Source: Cerebrovascular Diseases Extra - Category: Neurology Source Type: research
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Source: Oncology Letters - Category: Cancer & Oncology Tags: Oncol Lett Source Type: research
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Source: Clinical Imaging - Category: Radiology Authors: Tags: Neuroradiology Source Type: research
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Source: Clinical Neuroradiology - Category: Neurology Source Type: research
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Source: The Canadian Veterinary Journal - Category: Veterinary Research Authors: Tags: Can Vet J Source Type: research
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Source: Frontiers in Neurology - Category: Neurology Source Type: research
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Source: Journal of the Royal College of Physicians of Edinburgh - Category: General Medicine Tags: J R Coll Physicians Edinb Source Type: research
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