In-hospital mortality in patients admitted to Australian intensive care units with COVID-19 between 2020 and 2024

Matthew T Donnan^{1

2}, Peinan Zhao³, Allen C Cheng^{4

5}, Aaliya Ibrahim⁶, Annamaria Palermo⁷, Benjamin Reddi^{8

9}, Claire Reynolds¹⁰, Craig French^{11

12}, Edward Litton^{7

13}, Hannah Rotherham^{14

15}, Husna Begum¹⁶, Jamie Cooper^{1

16}, Jodi Dumbrell¹⁶, Lewis Campbell^{17

18}, Mark Plummer¹⁴, Mahesh Ramanan¹⁹, Patricia Alliegro¹⁶, Richard E McAllister²⁰, Simon Erickson²¹, Shweta Priyadarshini²², Sze Ng¹⁶, Tessa Broadley¹⁶, Tony Trapani¹⁶, Vicki Papanikolaou¹⁶, Winston Cheung²³, Andrew A Udy^{1

3

16}, Aidan Burrell^{1

3

16}

Affiliations

¹ Department of Intensive Care and Hyperbaric Medicine, The Alfred Hospital, Melbourne, Australia.
² Department of Respiratory Medicine, The Alfred Hospital, Melbourne, Australia.
³ School of Translational Medicine, Monash University, The Alfred Hospital, Melbourne, Australia.
⁴ School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia.
⁵ Monash Infectious Diseases, Monash Health and School of Clinical Sciences, Monash University, Clayton, VIC, Australia.
⁶ Health Protection Policy and Surveillance Division, Interim Australian Centre for Disease Control (CDC), Australia Government Department of Health and Aged Care, Australia.
⁷ Intensive Care Unit, Fiona Stanley Hospital, Perth, WA, Australia.
⁸ Royal Adelaide Hospital, Adelaide, SA, Australia.
⁹ University of Adelaide, Adelaide, SA, Australia.
¹⁰ Intensive Care Unit, St Vincent's Health Network, Sydney, NSW, Australia.
¹¹ The Australian and New Zealand Intensive Care Society (ANZICS) Centre for Outcome and Resources Evaluation, Melbourne, VIC, Australia.
¹² Department of Intensive Care, Western Health, Melbourne, VIC, Australia.
¹³ Department of Intensive Care Medicine, St John of God Hospital Subiaco, Perth, WA, Australia.
¹⁴ Intensive Care Unit, Royal Melbourne Hospital, Parkville, VIC, Australia.
¹⁵ Department of Critical Care, The University of Melbourne, Parkville, VIC, Australia.
¹⁶ Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, VIC, Australia.
¹⁷ Intensive Care Unit, Royal Darwin Hospital, Darwin, NT, Australia.
¹⁸ Menzies School of Health Research, Darwin, NT, Australia.
¹⁹ Intensive Care Unit, Caboolture Hospital, Caboolture, QLD, Australia.
²⁰ Department of Critical Care Medicine, Royal Hobart Hospital, Hobart, TAS, Australia.
²¹ Perth Children's Hospital, Perth, WA, Australia.
²² Department of Intensive Care Medicine, St Vincent's Healthcare Clinical Campus, Sydney, Australia.
²³ Department of Intensive Care Medicine, Concord Repatriation General Hospital, Sydney, NSW, Australia.

PMID: 40109285
PMCID: PMC11919585
DOI: 10.1016/j.ccrj.2024.11.003

In-hospital mortality in patients admitted to Australian intensive care units with COVID-19 between 2020 and 2024

Matthew T Donnan et al. Crit Care Resusc. 2025.

. 2025 Feb 28;27(1):100094.

doi: 10.1016/j.ccrj.2024.11.003. eCollection 2025 Mar.

Authors

Affiliations

¹ Department of Intensive Care and Hyperbaric Medicine, The Alfred Hospital, Melbourne, Australia.
² Department of Respiratory Medicine, The Alfred Hospital, Melbourne, Australia.
³ School of Translational Medicine, Monash University, The Alfred Hospital, Melbourne, Australia.
⁴ School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia.
⁵ Monash Infectious Diseases, Monash Health and School of Clinical Sciences, Monash University, Clayton, VIC, Australia.
⁶ Health Protection Policy and Surveillance Division, Interim Australian Centre for Disease Control (CDC), Australia Government Department of Health and Aged Care, Australia.
⁷ Intensive Care Unit, Fiona Stanley Hospital, Perth, WA, Australia.
⁸ Royal Adelaide Hospital, Adelaide, SA, Australia.
⁹ University of Adelaide, Adelaide, SA, Australia.
¹⁰ Intensive Care Unit, St Vincent's Health Network, Sydney, NSW, Australia.
¹¹ The Australian and New Zealand Intensive Care Society (ANZICS) Centre for Outcome and Resources Evaluation, Melbourne, VIC, Australia.
¹² Department of Intensive Care, Western Health, Melbourne, VIC, Australia.
¹³ Department of Intensive Care Medicine, St John of God Hospital Subiaco, Perth, WA, Australia.
¹⁴ Intensive Care Unit, Royal Melbourne Hospital, Parkville, VIC, Australia.
¹⁵ Department of Critical Care, The University of Melbourne, Parkville, VIC, Australia.
¹⁶ Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, VIC, Australia.
¹⁷ Intensive Care Unit, Royal Darwin Hospital, Darwin, NT, Australia.
¹⁸ Menzies School of Health Research, Darwin, NT, Australia.
¹⁹ Intensive Care Unit, Caboolture Hospital, Caboolture, QLD, Australia.
²⁰ Department of Critical Care Medicine, Royal Hobart Hospital, Hobart, TAS, Australia.
²¹ Perth Children's Hospital, Perth, WA, Australia.
²² Department of Intensive Care Medicine, St Vincent's Healthcare Clinical Campus, Sydney, Australia.
²³ Department of Intensive Care Medicine, Concord Repatriation General Hospital, Sydney, NSW, Australia.

PMID: 40109285
PMCID: PMC11919585
DOI: 10.1016/j.ccrj.2024.11.003

Abstract

Objective: To describe and compare the demographics, management, and outcomes for patients with COVID-19 admitted to intensive care units (ICUs) in Australia across the various waves of the COVID pandemic.

Design setting and participants: People aged ≥16 years who were admitted to a participating ICU with confirmed COVID-19 in the Short Period Incidence Study of Severe Acute Respiratory Infection (SPRINT-SARI) Australia study between February 2020 and May 2024.

Main outcome measures: Primary outcome: In-hospital mortality. Secondary outcomes: ICU mortality; ICU and hospital lengths of stay; supportive and disease-specific therapies.

Results: From 27 February 2020 to 18 May 2024, 10171 people were admitted to 72 ICUs with confirmed COVID-19 disease. The Wild Type wave included 518 (5.1%) patients, the Delta wave 2467 (24.3%) patients, and the Omicron wave 7186 (70.7%) patients. The median (IQR) age was 61 (49-70) years, 54 (41-66) years, and 65 (45-75) years, respectively (P < 0.001). The proportion of vaccinated cases increased in successive waves (1% vs 23.9% vs 65.1%) but plateaued in the Omicron subvariant waves (range 60.0%-71.9%). Invasive mechanical ventilation use decreased across successive waves (52.5% vs 43.6% vs 31.7%, P < 0.001). Use of extracorporeal membrane oxygenation was highest during the Delta wave (3.6%, 83 patients, median duration 18 days [IQR 9.8-35]). Multivariable analysis demonstrated an increased risk of in-hospital mortality among patients admitted during the Delta (adjusted HR 1.80, 95% CI: 1.38-2.35, p < 0.001) and Omicron (adjusted HR 1.88, 95% CI: 1.46-2.42, p < 0.001) waves when compared to the Wild Type wave.

Conclusion: COVID-19 continues to manifest significant morbidity and mortality in those requiring ICU admission. Despite a reduced need for ICU level supports, patients admitted during the Omicron wave demonstrated the highest in-hospital mortality.

Keywords: COVID-19; ICU; Mechanical Ventilation; Omicron; Outcomes; Pandemic.

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Conflict of interest statement

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: SPRINT-SARI Australia reports financial support was provided by Department of Health, Commonwealth of Australia. Andrew Udy, Mark Plummer and Edward Litton declare they are part of the CC&R editorial team as associate editors. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

**Fig. 1**
Cumulative patients admitted to ICU with COVID-19.

**Fig. 2**
Multivariable analysis (Cox regression) of in-hospital mortality. *Reference: Wild Type wave.*

**Fig. 3**
Adjusted survival probability following ICU admission with COVID-19.

See this image and copyright information in PMC

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In-hospital mortality in patients admitted to Australian intensive care units with COVID-19 between 2020 and 2024

Affiliations

In-hospital mortality in patients admitted to Australian intensive care units with COVID-19 between 2020 and 2024

Authors

Affiliations

Abstract

Conflict of interest statement

Figures

References

LinkOut - more resources

Full Text Sources