Identification of Desaturation Episodes by Means of Continuous Measurement of Oxygen Saturation During Hemodialysis

Inclusion Criteria: * Age ≥18 years and able to give written informed consent to the study * On chronic hemodialysis for ≥ 90 days at time of enrollment * Ability to read * Consent to have video recording taken during study visit Exclusion Criteria: * Subjects with cognitive impairment to consent * Sickle cell anemia * Prescription of nasal oxygen * Simultaneous participation in another clinical trial that may affect breathing frequency/patterns, blood oxygenation, sleep/wake cycle or other parameters related to the outcomes of interest to this study * Use of a breathing device, e.g. CPAP * Central venous catheter used as vascular access for hemodialysis * Artificial fingernails (may disturb the measurement of the WatchPAT) * Use of one of the following medications: alpha blockers, short acting nitrates (less than 3 hours before the study). * Permanent pacemaker * Sustained non-sinus cardiac arrhythmias.