Dr Paul Maclure1, Dr Samuel Gluck2, Dr Andrew Pearce2, Dr Mark Finnis3
1Lyell McEwan Hospital , Adelaide, Australia,
2SAAS MedSTAR , Adelaide , Australia ,
3Royal Adelaide Hosptial , Adelaide , Australia
To estimate the effect of the retrieval process on mortality for patients admitted to a mixed adult Intensive Care Unit (ICU) compared with propensity matched, non-retrieved controls.
Materials & Methods
Patients retrieved to the Royal Adelaide Hospital (RAH) ICU between 2011 and 2015 were propensity score matched for age, gender, Aboriginal Torres Strait Islander (ATSI) status, APACHE III score and diagnostic group with non-retrieved ICU admissions to estimate the average treatment effect of retrieval on hospital mortality. Factors associated with mortality in those retrieved were assessed by multiple logistic regression.
Retrieved patients comprised 1,597 (14%) of 11,641 index ICU admissions; this group were younger, mean (sd) 53 (18.5) versus 59 (17.7) years, had higher APACHE III scores, 61 (30.3) versus 56 (27.5), were more likely to be indigenous (5.1% versus 3.7%) and to have sustained trauma (34% versus 9%). The average treatment effect for retrieval on hospital mortality, risk difference (95% confidence interval), was -0.7% (-2.8, 1.3), P=0.50. Variables independently associated with hospital mortality in those retrieved included age, APACHE III score and diagnostic category. Time from retrieval team activation to arrival with patient, rural location, radial distance from the RAH and population size at the retrieval location were not significantly associated with mortality.
The hospital mortality for retrieved patients was not significantly different when compared with propensity-matched controls. Mortality in those retrieved was associated with increasing age, APACHE III score and diagnostic category, however, was independent of time from team activation to arrival with patient.