Irish National ICU Audit Annual Report 2021 Key Findings

Key Findings
INICUA captured activity in 22 adult public hospitals, which collectively provided 96% of Level 3 ICU care in adult HSE-funded hospitals in 2021. The ICU audit documented 12,151 admissions of 11,420 patients to 26 Units in 22 hospitals. The mean length of stay was 6.6 days.
Data in this report provides detailed insights into the complexity and volume of care provided in each Unit, with implications for resource requirements when planning ICU services. A key metric in defining the complexity of care provided is the number of bed days where the Patient is undergoing invasive ventilation. The Report provides data for each Unit on (i) the total number of bed days with invasive ventilation and (ii) bed days with invasive ventilation as a percentage of total bed days.
Hospitals with the largest numbers of bed days where the Patient is undergoing invasive ventilation were St James’s Hospital, Beaumont Hospital, Mater Misericordiae Hospital, Cork University Hospital and St Vincent’s Hospital.
On average, 303 ICU/HDU beds were open daily in publicly funded hospitals in 2021 (ICU-BIS data). This corresponded to 6.0 critical care beds per 100,000 population; the average for OECD countries was 14.1/100,000.
The average bed-occupancy rate nationally was 88.5%. Recommendations for bed-occupancy rates range from 75% to 85%. Occupancy rates below this range indicate unnecessary allocation of expensive resources, while occupancy above this range suggests that the Unit will be unable to cope with surges in demand, and that admission of critically ill patients will frequently be delayed. A number of Units, including some of the larger Units, had bed-occupancy rates greater than 90% for 2021 (St Vincent’s Hospital, Mater Hospital, Cork University Hospital, Beaumont Hospital and Mercy University Hospital).
In keeping with the high bed-occupancy levels, there was evidence that patients were being discharged before they were fully ready for ward care. INEWS scores at ICU discharge were relatively high in some Units, with median INEWS scores of 4 and upper quartile INEWS scores of 6.
Despite the high bed-occupancy levels, delays in discharges of patients judged ready for ward care were common; 3.3% of bed days were occupied by patients cleared for discharge for over 8 hours.
Mean length of stay (LOS) was 6.6 days in 2021 (compared with 5.8 days in 2020). The increased LOS is due to greater numbers of COVID-19 patients who had a longer LOS (see below). The median LOS was 3 days.
COVID-19 disease had a major impact on ICU activity in 2021. Our audit documented 1,671 patients admitted to ICU with a diagnosis of COVID, which represents 15% of all patients admitted to ICU in 2021. Length of stay was over twice as long for COVID-19 patients, and they accounted for 29% of all ICU beds occupied in 2021.
Other common reasons for ICU admission were surgery (35% of admissions), sepsis (37%) and trauma (7.6%). There were 284 admissions as a result of traumatic brain injury, 130 of these to Beaumont Hospital.
A requirement for in-hospital cardiopulmonary resuscitation (CPR) before admission to ICU is suggestive of unrecognised deterioration in the ward. The rates of requirement for CPR ranged from 0.4% to 11% between different Units, suggesting potential for intervention in hospitals with higher rates. The national rate of patients requiring CPR before ICU admission has remained unchanged over the 5 annual ICU Audit reports despite investments in outreach, in early warning scores and in education about the deteriorating patient.
Fifty-three children under 16 years were admitted to adult ICU in 2021, a decrease of more than 50% since 2019, reflecting a move towards admitting children to specialist paediatric Units.
One hundred and ninety-six patients who were pregnant or recently pregnant (within 6 weeks of Unit admission) were admitted, 31% more than in 2020. This increase was due to the admission of 73 pregnant or recently pregnant patients with COVID-19, all of whom survived.
Patients needed to be sicker to be admitted to ICU in Ireland, compared with the UK, as judged by mean APACHE II score and median predicted risk of acute hospital mortality (ICNARCH-2018 model). This suggests a shortage of ICU beds compared to the UK.
Units varied considerably in their rates of provision of dialysis, especially if days receiving dialysis were expressed as a proportion of days receiving invasive ventilation. The data indicate variability in both case mix and clinical practice between hospitals.
A key role of audit is to define quality indicators (QI) and measure how Units meet the targets for these. Prompt access to ICU improves outcomes for critically ill patients. The HSE has defined targets for the time of the decision to admit to arrival in ICU. Of the 18 hospitals with adequate data for this analysis, one met the target of 50% of admissions within one hour of a decision to admit (Beaumont Hospital). Fifteen hospitals met the target of 80% of patients admitted within 4 hours of a decision to admit, leaving only 3 hospitals which did not meet this target.
Another measure of timely admission to ICU is the proportion of patients who develop organ failure in four or more organ systems within 24 hours of admission. Outliers for this QI were St Vincent’s University Hospital, Connolly Hospital and Cork University Hospital. All of these hospitals have submitted action plans to achieve improved outcomes for this QI in the future.
Unplanned discharges at night suggest that patients not fully ready for ward care are being discharged to wards unfamiliar with the patients, and such unplanned discharges are therefore highly undesirable. University Hospital Galway and Cavan General Hospital were outliers for this QI in 2021. Both hospitals have submitted action plans to address this issue.
Unplanned readmission to ICU within 48 hours of discharge is a key QI which may reflect either pressure on Units to discharge prematurely or poor care in the ward to which the patient is discharged. There were no outlier Units for this QI in 2021.
The crude mortality rate in ICU was 18%. A further 6% of ICU admissions died after ICU discharge, before leaving hospital, giving a mortality rate of 24%. This represents a survival rate of 76%. These numbers are similar to data from comparable international Units.
A key QI of care in ICU is the acute hospital mortality rate adjusted for the relative risk of death by consideration of the factors known to affect mortality. Data from our audit are analysed by ICNARC, the organisation which runs ICU audit in the UK, and ICNARC analysis of our data makes it possible to directly compare outcomes in the Republic of Ireland with outcomes in the UK. The national risk-adjusted standardized mortality ratio (SMR) for ROI, calculated using the ICNARCH-2018 model, was similar to the SMR for the UK.
The national value for SMR was 1.16 compared to the 2020 value of 1.05; this increase is a possible cause for concern. This finding may, however, reflect greater numbers of COVID-19 patients in 2021.
No individual Units had risk-adjusted mortality rates outside the acceptable range for this QI. This indicates that quality of care in all these Units reached an acceptable standard.
A key finding of the audit was that risk-adjusted mortality outcomes were similar whether patients were initially admitted to a larger Unit (> 200 Level 3 patients annually) or to a smaller Unit (< 200 Level 3 patients annually). Similar outcomes for smaller and larger Units were found for the overall population of all patients admitted to ICU, for just high-risk patients (> 20% predicted risk of acute hospital mortality) and for COVID-19 patients. This finding differs from accepted wisdom regarding outcomes in smaller versus larger Unit. There are large numbers of inter-hospital transfers of patients within the Irish healthcare system, and we believe that this has achieved equality of risk-adjusted outcomes for critically ill patients across the system.
Six hundred and three COVID-19 patients died before discharge from acute hospital, giving a crude hospital mortality rate of 36%, compared to a 24% mortality rate for the overall ICU population.
Using the COVID-19 specific ICNARC model, the risk-adjusted 28-day in-hospital SMR for COVID-19 patients was 0.87, which was slightly better than the UK value of 1.0.
Data on multidrug-resistant organisms (MDROs) showed low rates of colonisation on admission to ICU with the exception of Vancomycin Resistant Enterococci (VRE) at 11%. Rates of Unitacquired transmission were low.
Brain death was diagnosed in 103 patients in our audited Units in 2021. Fifty of these patients became organ donors, a conversion rate of 48.5%. The most common reasons for not progressing to organ donation were families not assenting (27 patients) and organs being judged unsuitable by transplant teams although families had assented (12 patients).
There was considerable variability between Units in the rates of diagnosis of brain death and in the rates of progression from brain death to organ donation, although the numbers of patients in many Units were too small to draw conclusions.
Donations after circulatory death (DCD) increased to 10 in 2021, compared with 6 in 2020. The rate of DCD remains low compared to the rate in the UK. Inter-hospital transfers were an integral part of care pathways in the ROI. The audit identified 913 inter-hospital transfers to ICU in 2021. Transfers commonly occurred outside normal working hours; 44% occurred between 20.00 and 08.00, and 26% took place at weekends.
The specialties receiving the most transfers were respiratory medicine (16%), neurosurgery (13%) and general medicine (11%). In 2021 it is likely that many of the transfers to respiratory medicine represented COVID-19 patients who required advanced critical care.