Patient selection: critically-ill patient
Outcome: death after hospital discharge AND <= 30 days from ICU admission
Factors associated with increased risk:
(1) more severe illness, with a higher predicted in-hospital mortality rate at ICU admission (risk high if expected in-hospital mortality >= 10%, with increased risk if >= 1%)
(2) very short ICU stay (< 1 day)
(3) older age (>= 65 years of age)
where:
• The outcome of <= 30 days from ICU admission might tend to bias the effect of how long the person was in the ICU. A person in the ICU for 2 weeks would only be looked at for the 2 weeks after discharge. In addition, a person 2 weeks in the ICU would probably spend extra days on a ward prior to hospital discharge. A person in the ICU for 1 day would have 4 weeks after discharge to be at risk.
• A person with a very short ICU stay might be either under observation after surgery (relatively healthy) or someone transferred to another hospital (relatively unhealthy).
Factors associated with decreased risk:
(1) full-code status at the time of ICU admission (a person with a poor prognosis would be no-code)
(2) discharged home (vs acute care hospital, nursing home, etc)
Three of these factors are known at the time of ICU admission. The others are determined at time of discharge from the ICU or hospital.
