Effect of bolus injection versus continuous infusion of furosemide on diuresis and neurohormonal activation in patients with severe congestive heart failure

Previous studies have demonstrated that continuous infusion of furosemide results in increased diuresis and natriuresis compared with bolus administration of the drug in patients with severe heart failure. We reasoned that continuous infusion of furosemide caused less activation of neurohumoral mechanisms, since other studies have shown that bolus administration of furosemide may activate this system. We therefore tested the hypothesis that continuous administration of furosemide would increase water and sodium excretion due to less activation of neurohormones. Eight patients with severe heart failure were studied during continuous infusion over 24 h and bolus injections of furosemide twice daily in a randomized cross-over study. Bolus administration of furosemide increased diuresis and natriuresis significantly in the first 4 h after administration compared with continuous administration, but this was later reversed, resulting in similar 24 h total output. The neurohormones measured at baseline were all ...