Severe agitation among ventilated medical intensive care unit patients: Frequency, characteristics and outcomes

To determine the frequency, characteristics and outcomes of severe agitation among ventilated medical intensive care unit (MICU) patients. Prospective cohort study. Eighteen-bed MICU in 964-bed tertiary care center. All ventilated patients, aged 18 years or older and admitted for more than 24 h between January 1, 2001 and May 8, 2001. None. Data were collected daily by concurrent chart abstractions. Variables included sociodemographic, clinical, laboratory, pharmacologic and non-pharmacologic interventions, ventilator settings and adverse events. Severe agitation, the main outcome variable, was defined as two or more Motor Activity Assessment Scale (MAAS) scores above 4 in a 24-h period and sedative and/or narcotic doses above the established sedation and analgesia protocol or a combination of two or more sedatives. Twenty-three (16.1%) of 143 enrolled patients exhibited severe agitation. Agitated patients were younger (hazard ratio [HR] 1.32), more likely to be admitted from an outside hospital ICU (HR 2.48), had lower pH (HR 1.55) and PaO(2)/FIO(2) less than 200 mmHg (HR 2.59). Agitated patients had longer MICU stays (median 12 versus 5 days, p