Central haemodynamics and oxygen transport during CPPV with frequencies of 16 and 8 times per minute.
During the weaning period after 18 h of mechanical ventilation following open-heart surgery, central haemodynamics, systemic oxygen transport and total oxygen consumption were assessed in a total of 11 patients receiving continuous positive pressure ventilation. Mechanical ventilatory rates of 16 and 8 times per minute were studied. Systemic arterial pressure, cardiac index, stroke volume index, left ventricular stroke work index, rate-pressure-product, and systemic oxygen transport were observed to be higher during the lower ventilatory rate. Because transmural right atrial and pulmonary capillary wedge pressures were also higher during ventilation with a frequency of eight times per minute, the lower frequency may impede venous return less. This might explain the difference found in central haemodynamics between the two ventilation frequencies.
D000328:Adult; D001794:Blood Pressure; D002302:Cardiac Output; D006348:Cardiac Surgical Procedures; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D011175:Positive-Pressure Respiration / Q000009:adverse effects*; D013318:Stroke Volume
D010100:Oxygen