Mechanisms of improvement of water and sodium excretion by immersion in decompensated cirrhotic patients.

Eight patients with alcoholic liver disease, ascites, and edema were found to have impaired water (36 +/- 6% in 5 hr) and sodium (3.9 +/- 1.1 mEq/5 hr) excretion during a 20 ml/kg water load. These patients were submitted to a 5-hr head-out water immersion (HWI) with hemodynamic monitoring (Swan-Ganz). HWI increased cardiac index (3.3 to 4.2 liters/min/m2), right atrial pressure (RAP, 3.9 to 9.0 mm Hg), and wedge capillary pulmonary pressure (9.8 to 15.4 mm Hg) (all P less than 0.01). HWI decreased plasma renin activity (6.4 to 4.5 ng/ml/hr, P less than 0.001), aldosterone (73 to 43 ng/dl, P less than 0.001), arginine vasopressin (AVP, 1.03 +/- 0.15 to 0.76 +/- 0.08 pg/ml, P less than 0.005), norepinephrine (NE, 584 to 435 pg/ml, P less than 0.001) and increased the percentage of water load excreted (36 to 63%, P less than 0.005) and urinary sodium excretion (3.9 to 9.7 mEq/5 hr, P less than 0.05). The percentage of water load excreted was inversely correlated to AVP levels (r = 0.52, P less than 0.05) and directly correlated to RAP (r = 0.74, P less than 0.05). A significant positive correlation was also found between the increase in fractional excretion of sodium (delta FENa) and the increase in RAP (r = 0.77, P less than 0.001). FENa also correlated inversely with NE levels (r = 0.56, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)