In patients with severe heart failure, 100% oxygen administration significantly reduced cardiac output (from 3.7 to 3.1 liters/min, p<0.01) and increased systemic vascular resistance.
Does supplemental oxygen administration alter hemodynamic variables in patients with severe congestive heart failure?
Supplemental oxygen administration has detrimental hemodynamic effects in patients with severe heart failure, including reduced cardiac output and increased filling pressures, independent of sympathetic activity.
Absolute Event Rate: 3.1% vs 3.7%
p-value: p=< 0.01
OBJECTIVES: This study sought to determine the hemodynamic effects of oxygen therapy in heart failure. BACKGROUND: High dose oxygen has detrimental hemodynamic effects in normal subjects, yet oxygen is a common therapy for heart failure. Whether oxygen alters hemodynamic variables in heart failure is unknown. METHODS: We studied 10 patients with New York Heart Association functional class III and IV congestive heart failure who inhaled room air and 100% oxygen for 20 min. Variables measured included cardiac output, stroke volume, pulmonary capillary wedge pressure, systemic and pulmonary vascular resistance, mean arterial pressure and heart rate. Graded oxygen concentrations were also studied (room air, 24%, 40% and 100% oxygen, respectively; n = 7). In five separate patients, muscle sympathetic nerve activity and ventilation were measured during 100% oxygen. RESULTS: The 100% oxygen reduced cardiac output (from 3.7 +/- 0.3 to 3.1 +/- 0.4 liters/min mean +/- SE, p < 0.01) and stroke volume (from 46 +/- 4 to 38 +/- 5 ml/beat per min, p < 0.01) and increased pulmonary capillary wedge pressure (from 25 +/- 2 to 29 +/- 3 mm Hg, p < 0.05) and systemic vascular resistance (from 1,628 +/- 154 to 2,203 +/- 199 dynes.s/cm5, p < 0.01). Graded oxygen led to a progressive decline in cardiac output (one-way analysis of variance, p < 0.0001) and stroke volume (p < 0.017) and an increase in systemic vascular resistance (p < 0.005). The 100% oxygen did not alter sympathetic activity or ventilation. CONCLUSIONS: In heart failure, oxygen has a detrimental effect on cardiac output, stroke volume, pulmonary capillary wedge pressure and systemic vascular resistance. These changes are independent of sympathetic activity and ventilation.
Haque et al. (1996) studied Congestive heart failure (n=15). Supplemental oxygen vs. Room air was evaluated on Cardiac output (liters/min) (p=< 0.01). In patients with severe heart failure, 100% oxygen administration significantly reduced cardiac output (from 3.7 to 3.1 liters/min, p<0.01) and increased systemic vascular resistance.