Does volume or occupancy influence emergency access block? A multivariate time series analysis from a single emergency department in Sydney, Australia during the COVID-19 pandemic.

OBJECTIVE: The study aims to determine whether ED presentation volume or hospital occupancy had a greater impact on ED performance before and during the COVID-19 health response at a tertiary referral hospital in Sydney, Australia. METHODS: Single centre time series analysis using routinely collected hospital and ED data from January 2019 to September 2020. The primary outcome was ED access block measured by emergency treatment performance (ETP; i.e. percentage of patients who were discharged or transferred to a ward from ED within 4 h of ED arrival time). Secondary outcomes were hospital occupancy, elective theatre cases and ambulance ramping. Multivariate time series analysis was performed using vector autoregression, to model effects of changes in various endogenous and correlated variables on ETP. RESULTS: There was an increase in ETP, drop in ED presentations and decrease in hospital occupancy between April and June 2020. Elective surgery and hospital occupancy had significant effects up to 2 days prior on ETP, while there were no significant effects of either ED or ambulance presentations on ETP. Hospital occupancy itself increased with ED presentations after 2-4 days and decreased with elective surgery after 1 day. Shocks (a one standard deviation increase) in hospital occupancy had a peak impact nearly two times greater compared to ED presentations (-1.43, 95% confidence interval -1.92, -0.93 vs -0.73, 95% confidence interval -1.21, -0.25). CONCLUSION: The main determinants of the reduction of ED overcrowding and access block during the pandemic were associated with reductions in hospital occupancy and elective surgery levels, and more research is required to assess more complex associations beyond the scope of this manuscript.

Predictors and in-hospital mortality associated with prolonged emergency department length of stay in New South Wales tertiary hospitals from 2017 to 2018.

OBJECTIVE: To determine specific patient, clinical and service factors associated with increased ED length of stay and investigate whether prolonged ED length of stay, as measured by emergency treatment performance (ETP) non-compliance, is an independent predictor of all cause 30-day mortality for patients presenting to, and admitted from ED. METHODS: This was a retrospective analysis of linked state-wide emergency, inpatient and death data from New South Wales. All patients who presented to a tertiary level public hospital (level 5 or 6) ED and admitted to an in-patient unit were included. Outcomes were the proportion of admitted patients who met ETP targets, and 30-day all-cause mortality. RESULTS: A total of 697 600 eligible cases were identified and analysed. The odds of meeting ETP benchmarks were 62% lower in those with complex or multiple medical comorbidities (odds ratio 0.38, 95% confidence interval 0.37-0.40, P < 0.001) compared with patients with no medical comorbidities. Admission under psychiatry, surgical and oncology service-related groups were associated with decreased ETP. The hazard ratio for 30-day all-cause mortality over time was 28% higher in those not meeting ETP benchmarks after adjusting for age, triage category, comorbidities, ICU and service-related group (hazard ratio 1.28, 95% confidence interval 1.26-1.30, P < 0.001). CONCLUSION: Patients with complex and multiple medical comorbidities, and those admitted under certain service-related groups such as psychiatry, surgery and oncology were found to have poorer ETP performance. Overall, failure to meet ETP was associated with increased mortality after adjusting for age, case-mix, comorbidities and acuity.