Monitoring for Hypoxia in COPD Patients

A 65-year-old female patient is admitted to the hospital for chronic obstructive pulmonary disease (COPD) exacerbation. During the assessment, the nurse notes that the patient has not been using her nebulizer as prescribed. The healthcare provider has ordered oxygen therapy to maintain oxygen saturation levels above 90%. Which potential complication should the nurse monitor for as a priority in this patient?