The Psychiatric Domain of Post-Intensive Care Syndrome: A Review for the Intensivist

Post-intensive care syndrome (PICS) is a clinical syndrome characterized by new or worsening changes in mental health, cognition, or physical function that persist following critical illness. The psychiatric domain of PICS encompasses new or worsened psychiatric burdens following critical illness, including post-traumatic stress disorder (PTSD), depression, and anxiety. Many of the established predisposing and precipitating factors for the psychiatric domain of PICS are commonly found in the setting of critical illness, including mechanical ventilation (MV), exposure to sedating medications, and physical restraint. Importantly, previous psychiatric history is a strong risk factor for the development of the psychiatric domain of PICS and should be considered when screening patients to diagnose psychiatric impairment and interventions. Delirium has been associated with psychiatric symptoms following ICU admission, therefore prevention warrants careful consideration. Dexmedetomidine has been shown to have the lowest risk for development of delirium when compared to other sedatives and has been the only sedative studied in relation to the psychiatric domain of PICS. Nocturnal dexmedetomidine and intensive care unit (ICU) diaries have been associated with decreased psychiatric burden after ICU discharge. Studies evaluating the impact of other intra-ICU practices on the development of the psychiatric domain of PICS, including the ABCDEF bundle, depth of sedation, and daily spontaneous awakening trials, have been limited and inconclusive. The psychiatric domain of PICS is difficult to treat and may be less responsive to multidisciplinary post-discharge programs and targeted interventions than the cognitive and physical domains of PICS. Given the high morbidity associated with the psychiatric domain of PICS, intensivists should familiarize themselves with the risk factors and intra-ICU interventions that can mitigate this important and under-recognized condition.