Using Continuous Positive Airway Pressure to Reduce the Incidence of Acute Kidney Injury in Hospitalized Patients With Chronic Kidney Disease

Using Continuous Positive Airway Pressure to Reduce the Incidence of Acute Kidney Injury in Hospitalized Patients With Chronic Kidney Disease

Obstructive sleep apnea (OSA) is a common and undertreated condition in patients with chronic kidney disease (CKD). Both physiologic and empiric data suggest that renal hypoxia due to OSA is associated with worsening kidney function. Hospitalized patients are often exposed to multiple nephrotoxins such as antibiotics, contrast agents, and diuretics, which place them at risk for acute worsening of kidney function. This study aims to determine whether immediate diagnosis and treatment of OSA in CKD patients will decrease the incidence of acute kidney injury during hospitalization. The investigators will evaluate the extent to which this effect can be attributed to a decrease in nocturnal hypoxia and improved blood pressure control. Secondary endpoints include hospital length of stay, and a composite outcome comprised of hemodialysis initiation, major cardiovascular events, and mortality.

incidence of acute kidney injury during hospitalization (defined as an increase in creatinine by 0.5 mg/dl or more)

Composite outcome of a) Incidence of major cardiovascular event (acute coronary syndrome, major arrhythmia, or exacerbation of CHF), b) Initiation of hemodialysis c)In-hospital mortality

Inclusion Criteria: CKD defined by National Kidney Foundation Staging system: eGFR < 60 Overnight sleep study consistent with OSA Exclusion Criteria: Currently treated with positive airway pressure for sleep-disordered breathing Hemodynamically unstable, defined as SBP < 90, or use of vasopressors Intubated or mechanically ventilated Respiratory insufficiency, defined as P/F ratio < 250, or requiring mechanical ventilation End stage renal disease on renal replacement therapy Contraindication to CPAP, including active emesis, recent intracranial surgery, altered level of consciousness

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