STUDIES ON THE LOWER URINARY TRACT OBSTRUCTION (III. REPORT)

BLOOD pH AND UREA NITROGEN IN CASES OF LOWER URINARY TRACT OBSTRUCTION

Abstract

Studies of blood pH values and urea nitrogen (B. U. N.) levels before and after the continuous drainage were made in 73 cases having lower urinary tract obstruction.
(A) Patients whose renal function was normal or only slightly impaired;
In most cases of this group, blood pH values were within normal range before the drainage. Several patients who were complaining complete urinary retention showed some degree of acidosis, but after the drainage these acidosis disappeared rapidly.
B. U. N. levels of this group before the drainage showed normal (below 20mg/dl) in about two-fifth of them. The remainder were over 20mg/dl, but the patients whose B. U. N. levels increased over 30mg/dl were very rare even in the condition of complete urinary retention. After the drainage, B. U. N. levels soon fell down under 20mg/dl in all cases.
(B) Patients whose renal function was moderately or severely impaired;
In this group, blood pH values before the drainage were usually abnormal. Many of them showed hyperchloremic acidosis, but sometimes alkalosis could be seen.
B. U. N. levels before the drainage were sometimes normal or only slightly higher, but in most cases over 30mg/dl.
In the post-drainage course, there was a distinct difference according to the degree of renal damage, i. e. whether moderate or severe. When the renal damage was moderate and yet reversible, so not only B. U. N. levels but also Na, Cl concentrations and pH values of blood became normal following adequate fluid and electrolyte therapy usually within 2 or 3 weeks.
But most of the patients whose renal damage was severe and became irreversible showed that, in spite of long continuous drainage over months, B. U. N. levels were continuously above 30mg/dl and that unstability of blood electrolyte and pH persisted.