The advent of the SARS-CoV-2 pandemic brought unprecedented challenges to healthcare systems worldwide. As the virus spread across continents, hospitals faced a surge in patient admissions, particularly to intensive care units (ICUs). Understanding the impact of the pandemic on the sickest patients admitted to hospital is crucial for enhancing preparedness for future outbreaks. In this edition of the journal, authors from Denmark report on a register-based national observational study that sheds light on the changes in ICU admission rates and demographic profiles of patients during the initial phase of the pandemic.¹

Shifts in ICU admission rates

The study revealed a notable decline in the number of ICU admissions during the first wave of the COVID-19 pandemic in Denmark. This decline was particularly pronounced in specific age groups, with fewer admissions observed among individuals below 18 years and those aged 70 and above. Such shifts in admission rates underscore the dynamic nature of healthcare utilization patterns in response to external crises but might also be due to real or perceived chances of survival of elderly or frail patients with COVID19.² Understanding these changes is vital for ensuring equitable access to critical care services across all demographics.

Demographic profile of ICU patients

Despite the decline in admission rates, the demographic profile of patients admitted to ICUs remained relatively stable during the pandemic's first wave. The study found no significant changes in the gender distribution or the prevalence of comorbidities among ICU patients. This might highlight the resilience of some healthcare systems in managing critical care needs amidst a global health crisis.

Impact on other admissions and hospital stay

One of the notable findings of the study was the decrease in elective ICU admissions as healthcare resources were reallocated to prioritize COVID-19 patients, and elective procedures and admissions were deferred, leading to a reduction in non-urgent ICU admissions.

Hospital level data from the US confirms the shift in admission rates to hospital: the number of patients admitted to hospital with non-COVID diagnoses declined during early 2020 and while rates of admissions with cancer did recover within a few months many patients with other conditions stayed away.³

Analysis of data from ICU admissions in 15 countries showed increased mortality for patients with non-COVID diagnoses in low-income countries contrasting with better survival in high income countries.⁴ In contrast to the data from the Danish cohort, an analysis of data from 71 Dutch ICUs showed lower patient volume of admissions of non-COVID patients and a selection of patients with fewer comorbidities. Despite this, there was a modest increase in the case-mix adjusted mortality.⁵

The change might have affected groups of patients with different conditions differently: notably leading to a reduction in the rate of patients requiring cardiac surgery or transplants.⁶ While there was a marked reduction in ICU admissions following emergency surgery in the UK, mortality from these conditions increased.⁷

The Danish study further identified an increase in the length of hospital stay prior to ICU admission during the pandemic. This delay in ICU admission could be attributed to a number of factors, including the lower proportion of surgical admissions, or - more directly related to COVID-19 - inexperience with the disease or concerns about overwhelming ICUs. While ICU capacity in the UK was increased dramatically in Denmark the surge was only in the order of 30%.⁸

Learnings for healthcare preparedness and governmental decision-making

Several countries have reported national data on ICU admissions during the pandemic: Sweden⁹ and the UK¹⁰ have published mortality rates of patients with COVID during a time when assumed and real pressure on beds led to dramatic increases in ICU capacity¹¹ and concerns about availability of appropriate treatment options.¹²

The requirement for strict Infection Prevention and Control measures, aimed at reducing nosocomial infection, complicates how critical care, and indeed overall hospital care, can be provided, particularly in the early stages of a pandemic when we have limited knowledge about how the pathogen is transmitted. We do not know from this study, whether these issues reduced the overall capacity of critical care in Denmark, and could in part explain why fewer patients were admitted.

It is notable, that even at the peak of COVID-19 admissions in week 13 of the data reported in the study, COVID-19 patients accounted for only 12% of the overall ICU population. This contrasts starkly with UK experience, where at the time of peak pressure, the overwhelming majority of ICU patients were unwell with Covid, exceeding our baseline critical care beds, staff and equipment, and requiring us to open up new capacity.¹³ Multiple public health and societal reasons are likely to explain these differences, predominantly the timing and effectiveness of lockdowns.

The interactions of care delivered to patients with COVID-19 and those without COVID-19 have significant implications for healthcare preparedness and response strategies in managing future pandemics or public health emergencies: The increase in the length of hospital stay prior to ICU admission highlights the need for streamlined pathways for expedited critical care assessment and management. Investing in methods for early detection and intervention protocols might help minimize delays in accessing essential healthcare services, particularly during periods of heightened demand.

Conclusion

The study provides valuable insights into the dynamics of ICU admissions during the first wave of the COVID-19 pandemic in Denmark. While the overall number of admissions declined, certain demographic groups experienced more pronounced reductions, highlighting the importance of equitable healthcare delivery. The stability of the demographic profile of ICU patients underscores the resilience of healthcare systems in responding to crises. However, challenges such as delayed ICU admissions and decreased elective admissions with subsequence problems in the recovery of capacity against growing waiting lists for patients awaiting elective surgery underscore the need for ongoing vigilance and adaptive strategies in healthcare delivery.¹⁴ By learning from the experiences of the pandemic, healthcare systems can better prepare for future challenges and ensure equitable access to critical care services for all patients.

References

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