Chronic critical illness is a devastating syndrome of prolonged respiratory failure and other derangements. To our knowledge, no previous research has addressed brain dysfunction in the chronically critically ill, although this topic is important for medical decision making.
We studied a prospective cohort of 203 consecutive, chronically critically ill adults transferred to our hospital's respiratory care unit (RCU) after tracheotomy for failure to wean. We measured prevalence and duration of coma and delirium during RCU treatment using the Confusion Assessment Method for the Intensive Care Unit with the Richmond Agitation-Sedation Scale. To assess survivors (at 3 and 6 months after RCU discharge), we used a validated telephone Confusion Assessment Method.
Before hospitalization, most (153 [75.4%]) of the 203 patients in the study were at home, completely independent (115 [56.7%]), and cognitively intact (116 [82.0%]). In the RCU, 61 (30.0%) were comatose throughout the stay. Approximately half of patients (66 of 142) who were not in coma were delirious. Patients spent an average of 17.9 days (range, 1-153 days) in coma or delirium (average RCU stay, 25.6 days). Half of survivors (79 of 160) had one of these disturbances at RCU discharge. At 6 months, three fourths (151) of the study patients were dead or institutionalized; of 85 survivors, 58 (68.2%) were too profoundly impaired to respond to telephone cognitive assessment, and 53 (62.4%) were dependent in all activities of daily living.
Severe, prolonged, and permanent brain dysfunction is a prominent feature of chronic critical illness. These data, together with previous reports of symptom distress and rates of mortality and institutionalization, describe burdens for chronically critically ill patients receiving continued life-prolonging treatment and for their families.