Accessibility of the Australian population to an ICU, and of ICUs to each other.

OBJECTIVE To use a geographic information system to qualitatively and quantitatively illustrate the geospatial relationship of the Australian population to intensive care resources. DESIGN, SETTING AND PARTICIPANTS Intensive care unit data were sourced from the Australian and New Zealand Intensive Care Society Centre for Outcome and Resource Evaluation critical care resources survey (2007-2008) and adult patient database (2002-2008), and postcode data (2006) from the Australian Bureau of Statistics. Remoteness was classified within remoteness categories and the Accessibility/Remoteness Index of Australia Plus. Distance was the difference between two postcode's centroids. RESULTS Ninety-one public ICUs were identified. Of these, 50 (54.9%) were in a major city, 24 (26.4%) were inner regional, 15 (16.5%) were outer regional, one (1.1%) was remote and one (1.1%) was very remote, compared with 64.2%, 20.8%, 11.7%, 1.9% and 1.4% of the population, respectively (P = 0.324). Median population distance to the closest ICU was 35.9 km and closest Level 3 ICU was 54.8 km. This varied by state/territory, ranging from 7.6 km to the closest ICU for the Australian Capital Territory to 161.7 km for Western Australia. Overall, 84.8% of the Australian population were 0-50 km from an ICU, 12.9% were 51-300km, 2.3% were 301-1500 km, and 0.01% were > 1500km. This varied among the states/territories. A Level 3 ICU was the closest ICU for 65.4% of the population, a Level 2 for 27.6% and a Level 1 for 7%. Median distance between any two ICUs was 21.1 km. Generally, the distance between Level 3 ICUs was shorter than the distance to a Level 1 or Level 2 ICU. CONCLUSIONS The distribution of Australian ICUs and the Australian population was similar. However, accessibility varied by state/territory.