Intensive care utilisation after elective surgery in Australia and New Zealand: A point prevalence study

Objective: We aimed to describe the characteristics, outcomes and resource utilisation of patients being cared for in an ICU after undergoing elective surgery in Australia and New Zealand (ANZ). Methods: This was a point prevalence study involving 51 adult ICUs in ANZ in June 2021. Patients met inclusion criteria if they were being treated in a participating ICU on he study dates. Patients were categorised according to whether they had undergone elective surgery, admitted directly from theatre or unplanned from the ward. Descriptive and comparative analysis was performed according to the source of ICU admission. Resource utilisation was measured by Length of stay, organ support and occupied bed days. Results: 712 patients met inclusion criteria, with 172 (24%) have undergone elective surgery. Of these, 136 (19%) were admitted directly to the ICU and 36 (5.1%) were an unplanned admission from the ward. Elective surgical patients occupied 15.8% of the total ICU patient bed days, of which 44.3% were following unplanned admissions. Elective surgical patients who were an unplanned admission from the ward, compared to those admitted directly from theatre, had a higher severity of illness (AP2 17 vs 13, p<0.01), require respiratory or vasopressor support (75% vs 44%, p<0.01) and hospital mortality (16.7% vs 2.2%, p < 0.01). Conclusions: ICU resource utilisation of patients who have undergone elective surgery is substantial. Those patients admitted directly from theatre have good outcomes and low resource utilisation. Patient admitted unplanned from the ward, although fewer, were sicker, more resource intensive and had significantly worse outcomes.