Table 1 Selected clinical studies investigating post-ARDS cognitive impairment

Davidson et al.

Prospective cohort (n = 146)

Patients who survived ARDS experience significantly reduced quality of life following discharge compared to critically ill patients without ARDS

Hopkins et al.

Prospective cohort (n = 62)

Survivors of ARDS demonstrate cognitive impairments in memory, attention, concentration, and processing speed: 100% at discharge and 78% at 1 year after discharge

Contant et al.

Observational (n = 161)

ARDS following severe head injury results in severe intracranial hypertension. Targeting intracranial pressure rather than cerebral blood flow improves outcomes

Georgiadis et al.

Prospective interventional (n = 20)

In patients with acute stroke receiving mechanical ventilation, changes in cerebral perfusion pressure are mediated by mean arterial pressure rather than by positive end-expiratory pressure. Positive end-expiratory pressure does not increase intracranial pressure as long as hemodynamic stability is maintained

Holland et al.

Prospective cohort (n = 137)

In patients with traumatic brain injury, ARDS independently predicts mortality and is associated with worse long-term neurological outcome

Ely et al.

Prospective cohort (n = 275)

Delirium independently predicts higher mortality and longer hospital stay among patients treated with mechanical ventilation

Mascia et al.

Prospective interventional (n = 12)

Positive end-expiratory pressure does not affect intracranial pressure when inducing alveolar recruitment, but does lead to significant increases in PaCO₂ and intracranial pressure when inducing alveolar hyperinflation

Muench et al.

Prospective interventional (n = 10)

In hemodynamically unstable patients with severe subarachnoid hemorrhage, increases in positive end-expiratory pressure disturb cerebrovascular autoregulation, resulting in significant decreases in mean arterial pressure and regional cerebral blood flow

Mascia et al.

Observational (n = 82)

High-tidal-volume mechanical ventilation is associated with the development of ARDS after severe brain injury

Fong et al.

Secondary analysis of prospective cohort (n = 408)

Delirium accelerates cognitive decline in patients with probable or possible Alzheimer’s disease

Taccone et al.

Observational (n = 21)

Septic shock impairs cerebral autoregulation in patients with septic shock, particularly with concurrent hypercapnia

Janz et al.

Retrospective cohort (n = 7 from database of 379)

Brain autopsy of patients with ICU delirium shows hypoxic ischemic damage in the hippocampus, suggesting a link between ICU delirium and long-term cognitive impairment

van den Boogard et al.

Exploratory observational (n = 100)

The underlying mechanism of delirium may differ in patients with systemic inflammation versus patients without systemic inflammation and is mediated by different cytokines for each mechanism

Mikkelsen et al.

Prospective cohort (n = 102)

Survivors of ARDS 1 year following discharge demonstrate a confluence of cognitive impairment, psychiatric sequelae, and diminished quality of life. Hypoxemia and conservative fluid management are associated with these long-term impairments

Elmer et al.

Retrospective cohort (n = 697)

High-tidal-volume mechanical ventilation in patients with intracerebral hemorrhage is associated with the development of ARDS and increased mortality

Pandharipande et al.

Prospective cohort (n = 821)

At 12-month follow-up after discharge, 1/4 of patients who had been critically ill demonstrate cognitive impairment similar in severity to that seen in mild Alzheimer’s disease, and 1/3 similar in severity to that seen in traumatic brain injury

Needham et al.

Prospective cohort (n = 203)

At 6- and 12-month follow-up, ARDS survivors demonstrated impairments in 6-min walk distance and physical function outcomes. Minimizing the duration of intensive care and corticosteroid use may reflect modifiable risk factors

Girard et al.

Prospective cohort (n = 1040 enrolled, n = 586 follow-up)

Patients with ARDS, septic shock, or both experience multiple subtypes of delirium associated with long-term cognitive impairment at 3- and 12-month follow-up, including hypoxic, septic, unclassified, and sedative-associated delirium. The durations of these delirium subtypes predict worse cognitive function at 12-month follow-up, particularly sedative-associated delirium