Threat of COVID-19 impacting on a quaternary healthcare service: a retrospective cohort study of administrative data

OBJECTIVES: The threat of a pandemic, over and above the disease itself, may have significant and broad effects on a healthcare system. We aimed to describe the impact of the SARS-CoV-2 pandemic (during a relatively low transmission period) and associated societal restrictions on presentations, admissions and outpatient visits. DESIGN: We compared hospital activity in 2020 with the preceding 5 years, 2015–2019, using a retrospective cohort study design. SETTING: Quaternary hospital in Melbourne, Australia. PARTICIPANTS: Emergency department presentations, hospital admissions and outpatient visits from 1 January 2015 to 30 June 2020, n=896 934 episodes of care. INTERVENTION: In Australia, the initial peak COVID-19 phase was March–April. PRIMARY AND SECONDARY OUTCOME MEASURES: Separate linear regression models were fitted to estimate the impact of the pandemic on the number, type and severity of emergency presentations, hospital admissions and outpatient visits. RESULTS: During the peak COVID-19 phase (March and April 2020), there were marked reductions in emergency presentations (10 389 observed vs 14 678 expected; 29% reduction; p<0.05) and hospital admissions (5972 observed vs 8368 expected; 28% reduction; p<0.05). Stroke (114 observed vs 177 expected; 35% reduction; p<0.05) and trauma (1336 observed vs 1764 expected; 24% reduction; p<0.05) presentations decreased; acute myocardial infarctions were unchanged. There was an increase in the proportion of hospital admissions requiring intensive care (7.0% observed vs 6.0% expected; p<0.05) or resulting in death (2.2% observed vs 1.5% expected; p<0.05). Outpatient attendances remained similar (30 267 observed vs 31 980 expected; 5% reduction; not significant) but telephone/telehealth consultations increased from 2.5% to 45% (p<0.05) of total consultations. CONCLUSIONS: Although case numbers of COVID-19 were relatively low in Australia during the first 6 months of 2020, the impact on hospital activity was profound.