Relationship between renal furosemide excretion rate or urinary diuretic concentration (log value) and excretion of sodium in normal subjects (left curve) and in patients with CHF (right curve). Relationship between renal furosemide excretion rate or urinary diuretic concentration (log value) and excretion of sodium in normal subjects (left curve) and in patients with CHF (right curve). L K M De Bruyne Postgrad Med J 2003;79:268-271 Copyright © The Fellowship of Postgraduate Medicine. All rights reserved.