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Systemic cardiac output and distribution during high-frequency oscillation
Abstract:
High-frequency oscillation (HFO) appears to be an alternate, less traumatic mode of ventilating surfactant-deficient patients, because conventional (mechanical) pressure-limited ventilation (CMV) compromises cardiac function at high mean airway pressures. We compared systemic cardiac output and its distribution during HFO and CMV in ten adult rabbits rendered surfactant deficient by repeated pulmonary saline lavage. Cardiac output and organ blood flow were measured using the radionucleotide-labeled microsphere technique during ventilation at a mean airway pressure of 15 cm H2O and an inspired oxygen concentration of 100%. Both cardiac output and organ perfusion were similar during both modes of ventilation.
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