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C Kovijanic

Publications and source records attributed to C Kovijanic.

3 recordsLinked to original sources
PubMed1984

Beat frequencies in high-frequency positive-pressure ventilation.

Amplitude modulation of the waveforms of several cardiovascular variables was investigated during high-frequency (1.3 to 3.3 Hz) positive-pressure ventilation (HFPPV). The amplitude modulation of the pulmonary artery pressure wave was most prominent and its beat frequency (BF) was equal to the difference between the heart rate and the ventilation rate. Spectral analysis of the pulmonary artery pressure demonstrated well-defined peaks associated with the BF. No significant physiologic changes in either cardiovascular or pulmonary function were attributable to the presence of the beat phenomenon.

Animals↗
PubMed1984

High-frequency positive-pressure ventilation with the MA-1 ventilator.

A conventional, low-frequency ventilator was modified to ventilate dogs at high frequencies of 85 to 185 cycle/min while cardiovascular and pulmonary variables were monitored. Although gas transport was adequate, cardiac output was diminished when compared to low-frequency ventilation. The addition of an in-line pneumotachograph markedly increased PaCO2 during high-frequency ventilation. Carbon dioxide transport was primarily dependent upon the magnitude of the tidal volume at all high frequencies tested.

Animals↗