VCOM Louisiana Research Day Program

Clinical & Case Studies

Nora Rady, OMS-II; Sarah Voth, PhD Edward Via College of Osteopathic Medicine-Louisiana, Monroe, Louisiana 28 DELIRIUM PREDICTS ARDS-RELATED COGNITIVE IMPAIRMENT

Background: Patients recovering from acute respiratory distress syndrome (ARDS) frequently develop acute delirium and secondary organ damage, including impaired cognition. Physical and cognitive sequelae often chronically persist following discharge. This acute-to-chronic disease transition significantly impacts quality of life and is described by both post-intensive care syndrome and post-acute sequelae of COVID 19 (i.e., PASC or ‘Long COVID’). Both are disorders of chronic and often progressive impairment of physical, cognitive, and executive function, with comorbid anxiety and depression. Hypothesis: We hypothesize that delirium is an early manifestation of long-term neurocognitive decline post-discharge. Methods: PubMed was searched using key words/phrases: “ARDS”, “sequelae of ARDS”, “inflammation and ARDS”, “ARDS AND cognitive decline”, “Delirium”, “post-ICU cognitive impairment”, “ICU delirium AND PICS-related cognitive impairment”, “subjective experience of delirium ICU”, “ARDS AND amyloid”, and “post ICU cognitive impairment experience”. Clinical and basic science studies published between 2012 and 2022 were reviewed. Results: ARDS survivors suffer higher

healthcare costs and incidence of psychological and physical disability despite recovery of lung function. Between 70-100% of those recovered from acute ARDS exhibit significant neurocognitive decline. Patients report their experience of delirium as marked by a diminished sense of identity including feelings of dissociation, depersonalization, emotional dysregulation, and hallucinations. Physiologically, biomarkers including TNF- α , IL-6, IL-8, IL-10, amyloid-beta, tau, and high mobility group box 1 are elevated in critically ill patients and remain so up to 6 months post-discharge. Current evidence suggests proinflammatory elevation is associated with cognitive impairment whereas non-inflammatory mediators such as amyloid proteins promote neurocognitive decline similar to dementia and Alzheimer’s. Treatment strategies are currently limited to fluid and ventilatory management during the acute phase. MRI imaging studies indicate patients suffering from delirium often exhibit a decrease in both hippocampal and corpus callosum volumes. Hippocampal volume reduction is strongly predictive of cognitive impairment post-discharge e.g., diminished learning, memory, attention, executive function, and emotional regulation, with 50% of those affected performing below the 6 th percentile

in multiple assessments. Survivors describe struggling with a diminished quality of life including emotional lability, difficulty completing activities of daily living, rumination on their past, present, and future self, and a reduced role in the family dynamic. Conclusion: ARDS-related delirium is strongly predictive of cognitive dysregulation post discharge. Post-ARDS cognitive impairment often consists of both an acute stage (delirium) followed by a chronic stage of cognitive dysregulation/decline involving the lung-brain axis. It is an underrecognized clinical problem with significant physical and social impact for which new treatments are urgently needed.

41 2023 Via Research Recognition Day