Postrenal azotemia is a potentially life-threatening consequence of ur
inary obstruction. Its most serious consequences include fluid volume
deficits, hyperkalemia, and metabolic acidosis. Immediate therapy shou
ld be directed at restoring urine flow, correcting, extracellular flui
d volume deficits, minimizing the cardiac toxicity of hyperkalemia, an
d ameliorating the cardiovascular effects of metabolic acidosis. Most
patients respond quickly and completely to such therapeutic interventi
on.