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Updated: Jan 22, 2026

Invasive Hemodynamic Characterization of the Portal-hypertensive Syndrome in Cirrhotic Rats
Published on: August 1, 2018
Hemodynamic effects of portable non-invasive ventilation in healthy men
Nikolaos Chynkiamis1, Matthew Armstrong1, James Manifield1
1Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle Upon-Tyne, NE1 8ST, UK.
Abstract:
VitaBreath is a portable, non-invasive ventilation device (pNIV) that relieves shortness of breath in COPD by delivering fixed inspiratory and expiratory positive airway pressures (IPAP/EPAP: 18/8 cmH2O). Fixed pressures may cause circulatory compromise. We investigated the circulatory effects of pNIV during normal breathing (NB) and after Eucapnic Voluntary Hyperpnoea trials (EVH) sustained at 80% MVV. In a balanced order sequence, 10 healthy men performed four trials on one visit: 1-min of pNIV (intervention) or 1-min quiet breathing (QB) during NB; and 1-min pNIV (intervention) or 1-min QB during recovery from 3-min EVH. Compared to QB, pNIV application was associated with greater cardiac output (CO: 1.6 ± 1.9 L.min-1; P = 0.03). One minute into recovery from EVH, pNIV caused greater CO (2.2 ± 1.6 L.min-1; P = 0.01) compared to QB. Mean blood pressure was not different with pNIV compared to control. pNIV increased thoracoabdominal volumes and breathing frequency during NB and recovery from EVH. pNIV application does not induce adverse hemodynamic effects in healthy men.
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