Abstract A138: Nighttime Interruptions and Hospital-Acquired Delirium among Older Patients with Acute Ischemic Stroke: Analysis of Overnight Clinical Workflow Impacts on Patient Restfulness and Outcomes

Introduction: Achieving restfulness in the hospital environment is increasingly recognized as a patient-centered goal. We investigated whether clinical workflow-related nighttime interruptions impact hospital-acquired delirium (HAD) and discharge outcomes among older acute ischemic stroke (AIS) patients. Methods: We analyzed AIS patients aged ≥ 70 years across 7 stroke-certified hospitals (Jan 2018 to Jul 2025). Inclusion criteria were absence of delirium on admission and 2+ nights of hospital stay. Nighttime interruptions (10PM to 5AM) were extracted from EMR entries related to documentation of imaging, lab draws, medication administration, vital measurements, and hygiene care. A restful night was defined as 4+ uninterrupted hours. Overall restfulness was scaled for the hospital visit (percentage of total nights considered restful) and categorized as high (>75% restful nights), moderate (50-75%), or low (