Setting
The study was conducted in a 27-bed adult
cardiovascular medical ICU at Mission Hospital
in Mission Viejo, California, a 498-bed community
hospital. The diagnoses of patients admitted to
this unit included medical diagnoses (50%), cardiac
diagnoses including open heart surgery (34%-39%),
and surgical diagnoses (12%-14%). The mean annual
ICU daily census was 22.2 patients, with seasonal
fluctuations ranging from 12 to 27 patients. Staffing
was based on ratios and acuity with a ratio of 1 nurse
to 2 patients in most cases.