Plasma renin activity in end-stage kidney disease.

Plasma renin activity, fluid and electrolyte balance, and hemodynamic conditions were measured in seven hypertensive patients with end-stage renal disease before and after five exchanges of peritoneal dialytic fluids which removed large amounts of water and sodium, sodium but little water, and little water and sodium, respectively. The subjects had normal plasma renin activity, severe anemia, high cardiac output, high total peripheral resistance, and elevated blood volume. Plasma renin activity rose with large losses of sodium and water but changed slightly when large amounts of sodium with little water or small amounts of sodium and water were removed. Plasma renin activity prior to dialysis did not correlate with mean arterial pressure, blood volume, cardiac index, total peripheral resistance, or serum sodium concentration. Change in plasma renin activity with dialysis correlated inversely with change in mean arterial pressure, water balance, and change in cardiac output, and directly with change in total peripheral resistance and change in serum sodium concentration. There was no correlation with change in blood volume or sodium balance.