Intradialytic hypercapnic respiratory failure managed by noninvasive assisted ventilation.

We report a hemodialysis patient with acute hypercapnic respiratory failure managed on noninvasive intermittent positive pressure ventilation and progressive metabolic acidosis. Dialysate bicarbonate concentration of 25 mEq/l was associated with exacerbation of metabolic acidosis, while higher dialysate bicarbonate concentration of 30 mEq/l induced a dangerous increase in PCO(2) level. Excessive bicarbonate buffering and CO(2) production induced by severe metabolic acidosis, malnourishment and tissue hypoxia, could explain inadequate correction of metabolic acidosis and worsening of hypercapnia in this patient. Our findings suggest the need for close monitoring of blood gases and cautious modulation of dialysate bicarbonate concentration in the presence of progressive metabolic acidosis in hypercapnic hemodialysis patients. Copyright 2001 S. Karger AG, Basel