Critical illness can induce mental and physical impairments entirely separate from the illness that precipitates an intensive care unit admission. Delirium during an ICU stay is associated with increased risk of long-term cognitive impairment and post-ICU syndrome (PICS).
“Delirium is common in the hospital,” said Matthew Mart, MD, MSCI, postdoctoral research fellow and instructor in Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center. “Up to a quarter of patients in the general hospital population will experience delirium. In the ICU, that increases to a third. More than half of patients on mechanical ventilation have at least one episode of delirium.”
Delirium is a severe neurocognitive syndrome characterized by the acute onset of deficits in attention and cognition, he continued. Delirium is assessed using the Richmond Agitation Sedation Scale (RASS), which ranges from +4, combative, to -5, unarousable. ICU patients should be assessed daily for signs of delirium using either the CAM-ICU (Confusion Assessment Method for the ICU) or ICDSC (Intensive care Delirium Screening Checklist) instrument.
Mechanical ventilation is a risk factor for delirium, as are immobility, the use of benzodiazepines, polypharmacy, sleep deprivation, lack of communication with family and other modifiable factors.
“The cornerstone of management is focused on prevention,” Dr. Mart said. “Early rehabilitation is one of the few interventions shown to reduce the duration of delirium.”
The ABCDEF Bundle, a six-factor intervention, is even more effective, he added. Steps include:
Assess, prevent and manage pain
Both spontaneous awakening trials and spontaneous breathing trials
Choice of sedation and analgesia
Delirium: assess, prevent and manage
Early Mobility and exercise
Family engagement and empowerment
The ABCDEF approach can also limit the development of long-term cognitive impairment (LTCI) following critical illness. Interventions that reduce delirium reduce the risk of LTCI.
“Patients with any episode of delirium are more than twice as likely to show significant LTCI,” said Jayna M. Gardner-Gray, MD, FACEP, clinical assistant professor, Wayne State University. “Forty to 80 percent of ICU survivors have the functional equivalent of mild/moderate dementia.”
The cognitive, physical, and mental health impairments following acute illness are known as post-ICU syndrome (PICS).
“PICS doesn’t affect just the patient,” said Hugo Carmona, MD, assistant professor of pulmonary, critical care and sleep medicine, University of Washington. PICS also affects the family. “The burdens of caring for someone with PICS are quite high.”
Early mobilization and rehab can reduce the risk of PICS, just as it can reduce risk for delirium, he continued.
“Applying the ABCDEF bundle from the first day of admission improves the likelihood of discharge to home and reduces the risk of ICU readmission,” he said. “Any days of delirium are associated with later cognitive impairment. As you perform more of the ABCDEF bundle, you reduce risk.”
There have been few randomized controlled trials in post-ICU interventions to reduce or manage the symptoms of PICS, but consensus guidelines are emerging. The National Institute for Health and Care Excellence and the Society for Critical Care Medicine have developed similar approaches to reducing the physical, cognitive, and mental health impairments experienced by both ICU survivors and their families, reported Ann M. Parker, MD, PhD, assistant professor of pulmonary and critical care medicine, Johns Hopkins University School of Medicine.
Key components of ICU recovery programs include continuity of care from ICU to discharge, improvements in symptom status, managing expectations, validating progress, and reducing feelings of guilt and helplessness.
“We have all heard this from our patients,” Dr. Parker said. “We need to focus on the non-physical aspects of our post-ICU interventions.”