A subset of patients with acute exacerbation of chronic pulmonary disease present with concomitant acute renal failure (ARF). Acute hypercapnia remains an underappreciated and often overlooked cause of ARF in these patients with acute hypercapnic respiratory failure (AHRF). A nephrology consultation is requested for oliguric ARF in a woman with obesity-hypoventilation syndrome who has been admitted for AHRF and was treated with non-invasive ventilation. Despite stable hemodynamic status, the patient receives a large volume of intravenous fluids in an attempt to improve the renal function and urine output, and develops pulmonary edema and worsening respiratory status.
The decision is made to hemodialyze the patient for pulmonary edema and resistant hyperkalemia. However, prior to initiation of hemodialysis, the patient is intubated and started on mechanical ventilation because of progressively worsening respiratory status. This is followed by rapid improvement in hypercapnia and acidosis, and then by a significant increase in urine output....