Continuous monitoring with pulse oximeters can alert nurses to changes in patient status, but, like most electronic monitors, they can malfunction, resulting in occult hypoxemia (i.e., failure of pulse oximeter to detect clinically meaningful hypoxemia). This study assessed the potential of using frequency of nursing documentation of provider notification to identify unrecognized hypoxemia. Patients with both evident and occult hypoxemia had increased nurse documentation in the four hours before the hypoxic event. Crucially, this finding was also true in Black patients, where pulse oximeters are less likely to detect hypoxemia.