Chronic critical illness (CCI) does not have a single accepted definition. Most authors apply CCI to patients who survive an initial critical illness with mechanical ventilation or other intensive care therapies, but remain dependent on these technologies beyond 14 days, neither improving nor imminently declining. The usual CCI patient does not have respiratory failure in isolation. Instead, many have protracted comorbidities, such as neuromuscular weakness, debility, delirium, skin breakdown, and edema.

Approximately 5-10% of patients who require mechanical ventilation develop CCI. It can emerge from a critical illness for many reasons, including medical (e.g., pneumonia), surgical (complications after an operation), a stroke, or trauma. Risk factors for developing CCI have not been clearly established.

For many CCI patients, proceeding to tracheostomy and long-term ventilation represents a fundamental decision point, often arriving 14-21 days after critical illness presentation.
This is a challenging decision; clinicians should be aware of the following outcomes data:
- Mortality in CCI is high.
- Long-term functional outcomes in CCI are poor.
- Symptom burden in CCI is high.

See reference for more information.

Adapted from Hinrichs A and Rosielle DA. Palliative Care Network of Wisconsin. Fast facts and concepts #343. Chronic critical illness in adults. Internet. Accessed on January 4, 2018.