Factors determining renal response to water immersion in non-excretor cirrhotic patients

Abstract

Non-excretor cirrhotic patients, defined by their inability to normally excrete a standard water load, display variable responses to head-out water immersion. The hemodynamic, hormonal, and renal fucntional status of fifteen such patients were analyzed relative to water excretion during head-out water immersion. Group 1 patients (N = 7) all excreted less than 40% of the water load during immersion, whereas excretion was greater than 40% in all eight patients in Group 2. Group 1 patients, when compared with Group 2, had more ascites, more diuretic resistance, lower serum sodium concentration (125 ± 2 vs. 130 ± 1 mEq/liter, P < 0.05), and more impaired baseline water excretion (12.9 ± 1.2 vs. 35.9 ± 5.9% of water load in 5 hr, P < 0.005). Systemic hemodynamic responses to water immersion were similar in both groups. Glomerular filtration rate and renal plasma flow were significantly more impaired in Group 1 patients (insulin clearance 28 ± 6 vs. 62 ± 9 ml/min/1.73 m2, P < 0.05; para-aminohippurate clearance 212 ± 35 vs. 357 ± 37 ml/min, P < 0.05). Concentrations of plasma vasopressin (1.7 ± 0.5 vs. 0.8 ± 0.1 pg/ml, P < 0.05), renin (8.6 ± 1.7 vs. 3.8 ± 0.9 ng/ml/hr, P < 0.05), aldosterone (82 ± 14 vs. 39 ± 10 ng/dl, P < 0.05) and norepinephrine (1155 ± 183 vs. 603 ± 126 pg/ml, P < 0.05) were all significantly higher in Group 1 than Group 2 patients during water immersion. Thus, non-excretor cirrhotic patients are not homogenous and appear to comprise a spectrum with those patients in whom water excretion is most impaired, having tense ascites, diuretic resistance, lower serum sodium concentrations, more impaired renal function, and more marked abnormalities in the hormonal markers of decreased effective blood volume.