Do clinical and formal assessments of the capacity of patients in the intensive care unit to make decisions agree?

BACKGROUND: The complex environment and technology of intensive care unit (ICU) care may impair the ability of patients to participate in medical decision making or give informed consent. We studied the agreement of the intuitive assessments of residents and nurses of ICU patients' cognition, judgment, and decision-making capacity, and whether those assessments agreed with abbreviated formal mental status testing.
METHODS: Using a prospective survey case study, we assessed 200 English-speaking patients within 24 hours of their ICU admission. Formal assessment of cognition, judgment, and insight was performed by a research assistant. We obtained independent intuitive ratings by nurses and residents of patient cognition, judgment, and ability to participate in medical decision making or give informed consent.
RESULTS: Residents' and nurses' assessment of cognition and judgment showed a high degree of agreement with weighted ks of greater than 0.76. Assessments of cognition by residents and nurses agreed with Folstein Mini-Mental State Examination in 70% and 73.6% of cases, respectively. Forty percent of the population had an unimpaired Mini-Mental State Examination score of greater than 23, and an additional 12% of the subjects were mildly impaired with scores of 20 to 23. When asked whether they would approach patient or family for consent for an invasive procedure, nurses and physicians said they would request informed consent from 66% and 62% of the patients, respectively.
CONCLUSIONS: Residents and nurses caring for patients newly admitted to the ICU agree in their assessment of cognition, judgment, and capacity to participate in medical decision making, and are not unduly influenced by ventilator status. Their assessments correlate highly with abbreviated formal mental status testing.