Care Society Adult Patient Database Research Articles

Persistent Critical Illness and Long-Term Outcomes in Patients With COVID-19: A Multicenter Retrospective Cohort Study.

A nontrivial number of patients in ICUs experience persistent critical illness (PerCI), a phenomenon in which features of the ICU course more consistently predict mortality than the initial indication for admission. We aimed to describe PerCI among patients with critical illness caused by COVID-19, and these patients' short- and long-term outcomes. Multicenter retrospective cohort study. Australian and New Zealand Intensive Care Society Adult Patient Database of 114 Australian ICUs between January 1, 2020, and March 31, 2022. Patients 16 years old or older with COVID-19, and a documented ICU length of stay. The presence of PerCI, defined as an ICU length of stay greater than or equal to 10 days. We compared the survival time up to 2 years from ICU admission using time-varying robust-variance estimated Cox proportional hazards models. We further investigated the impact of PerCI in subgroups of patients, stratifying based on whether they survived their initial hospitalization. We included 4961 patients in the final analysis, and 882 patients (17.8%) had PerCI. ICU mortality was 23.4% in patients with PerCI and 6.5% in those without PerCI. Patients with PerCI had lower 2-year (70.9% [95% CI, 67.9-73.9%] vs. 86.1% [95% CI, 85.0-87.1%]; p < 0.001) survival rates compared with patients without PerCI. Patients with PerCI had higher mortality (adjusted hazards ratio: 1.734; 95% CI, 1.388-2.168); this was consistent across several sensitivity analyses. When analyzed as a nonlinear predictor, the hazards of mortality were inconsistent up until 10 days, before plateauing. In this multicenter retrospective observational study patients with PerCI tended to have poorer short-term and long-term outcomes. However, the hazards of mortality plateaued beyond the first 10 days of ICU stay. Further studies should investigate predictors of developing PerCI, to better prognosticate long-term outcomes.

Impact of frailty on long-term survival in patients discharged alive from hospital after an ICU admission with COVID-19

ObjectiveThough frailty is associated with mortality, its impact on long-term survival after an ICU admission with COVID-19 is unclear. We aimed to investigate the association between frailty and long-term survival in patients after an ICU admission with COVID-19. Design, Setting and ParticipantsThis registry-based multicentre, retrospective, cohort study included all patients ≥16 years discharged alive from the hospital following an ICU admission with COVID-19 and documented clinical frailty scale (CFS). Data from 118 ICUs between 01/01/2020 through 31/12/2020 in New Zealand and 31/12/2021 in Australia were reported in the Australian and New Zealand Intensive Care Society Adult Patient Database. The patients were categorised as ‘not frail’ (CFS 1-3), ‘mildly frail’ (CFS 4-5) and ‘moderately-to-severely frail’ (CFS 6-8). Main Outcome MeasuresThe primary outcome was survival time up to two years, which we analysed using Cox regression models. ResultsWe included 4028 patients with COVID-19 in the final analysis. ‘Moderately-to-severely frail’ patients were older (66.6 [56.3–75.8] vs. 69.9 [60.3–78.1]; p < 0.001) than those without frailty (median [interquartile range] 53.0 [40.1–64.6]), had higher sequential organ failure assessment scores (p < 0.001), and less likely to receive mechanical ventilation (p < 0.001) than patients without frailty or mild frailty. After adjusting for confounders, patients with mild frailty (adjusted hazards ratio: 2.31, 95%-CI: 1.75–3.05) and moderate-to-severe frailty (adjusted hazards ratio: 2.54, 95%-CI: 1.89–3.42) had higher mortality rates than those without frailty. ConclusionsFrailty was independently associated with shorter survival times to two years in patients with severe COVID-19 in ANZ following hospital discharge. Recognising frailty provides individualised patient intervention in those with frailty admitted to ICUs with severe COVID-19. Clinical trial registrationNot applicable.

Frailty and long-term survival among patients in Australian intensive care units with metastatic cancer (FRAIL-CANCER study): a retrospective registry-based cohort study

Recent advances in cancer therapeutics have improved outcomes, resulting in increasing candidacy of patients with metastatic cancer being admitted to intensive care units (ICUs). A large proportion of patients also have frailty, predisposing them to poor outcomes, yet the literature reporting on this is scarce. We aimed to assess the impact of frailty on survival in patients with metastatic cancer admitted to the ICU. In this retrospective registry-based cohort study, we used data from the Australia and New Zealand Intensive Care Society Adult Patient (age ≥16 years) database to identify patients with advanced (solid and haematological cancer) and a documented Clinical Frailty scale (CFS) admitted to 166 Australian ICUs. Patients without metastatic cancer were excluded. We analysed the effect of frailty (CFS 5-8) on long-term survival, and how this effect changed in specific subgroups (cancer subtypes, age [<65 years or ≥65 years], and those who survived hospitalisation). Because estimates tend to cluster within centres and vary between them, we used Cox proportional hazards regression models with robust sandwich variance estimators to assess the effect of frailty on survival time up to 4 years after ICU admission between groups. Between Jan 1, 2018, and March 31, 2022, 30 026 patients were eligible, and after exclusions 21 174 patients were included in the analysis; of these, 6806 (32·1%) had frailty, and 11 662 (55·1%) were male, 9489 (44·8%) were female, and 23 (0·1%) were intersex or self-reported indeterminate sex. The overall survival was lower for patients with frailty at 4 years compared with patients without frailty (29·5% vs 10·9%; p<0·0001). Frailty was associated with shorter 4-year survival times (adjusted hazard ratio 1·52 [95% CI 1·43-1·60]), and this effect was seen across all cancer subtypes. Frailty was associated with shorter survival times in patients younger than 65 years (1·66 [1·51-1·83]) and aged 65 years or older (1·40 [1·38-1·56]), but its effects were larger in patients younger than 65 years (pinteraction<0·0001). Frailty was also associated with shorter survival times in patients who survived hospitalisation (1·49 [1·40-1·59]). In patients with metastatic cancer admitted to the ICU, frailty was associated with poorer long-term survival. Patients with frailty might benefit from a goal-concordant time-limited trial in the ICU and will need suitable post-intensive care supportive management. None.

Long-Term Outcomes of Pulmonary Embolism Requiring Intensive Care Unit (ICU) Admission

Introduction:Pulmonary embolism (PE) requiring intensive care unit (ICU) admission is associated with high in-hospital mortality, however data on long-term survival outcomes and associated contributors remains limited. We sought to further investigate this using a large binational dataset. Methods:Retrospective cohort study of adults aged &amp;gt;16 years admitted to an Australian or New Zealand (NZ) ICU between January 1, 2018 and December 31, 2022 with a primary admission diagnosis of PE using the Australian and NZ Intensive Care Society (ANZICS) Adult Patient Database (APD). Data were available on baseline characteristics - specifically age, gender, admission co-morbidities (active malignancy, chronic cardiovascular, respiratory, renal and liver disease and illness severity as per the Acute Physiology and Chronic Health Evaluation (APACHE) III scoring system. The need for ICU-specific supports (vasopressors or inotropes, invasive and non-invasive ventilation [NIV], extracorporeal membrane oxygenation [ECMO]) was also recorded. All-cause mortality from 30 days to 48 months after ICU admission was obtained. Descriptive analyses, Kaplan-Meier and Cox proportional hazards models were used to describe survival during this time period. Ethical approval was granted by the Alfred Hospital Human Research Ethics Committee (HREC). Results:6447 patients with PE who had been admitted to 193 ICUs across Australia and NZ were identified, representing 9136 patient-years of follow-up. Median age was 66.5 years (interquartile range [IQR], 53-75). 24.5% were admitted to a rural or regional ICU. Median ICU length of stay was 46.6 hours (IQR, 27-79). Median APACHE III score was 42 (IQR, 31-56). Admission co-morbidities included active malignancy (8.1%), chronic respiratory (7.0%), renal (1.4%) and liver (0.4%) disease. Systolic blood pressure was was ≤90 mmHg at time of ICU admission in 1482 patients (23.9% of those in whom this data was available). Vasopressors or inotropes were required in 986 patients (17.6%), NIV was used in 713 (12.6%), invasive ventilation in 453 (8.0%) and 24 patients (0.43%) received ECMO. The mean duration of invasive ventilation where this was required was 14.9 hours. Kaplan-Meier survival analysis is shown in Figure 1. Overall survival was 92.3% at 30 days (95% CI, 91.6-93.0%), 87.5% at 6 months (95% CI, 86.5-88.3%), 84.4% at 12 months (95% CI 83.4%-85.4%) and 73.0% at 48 months (95% CI, 71.0-74.9%). Active malignancy was the strongest independent predictor of mortality (hazard ratio [HR] 3.3, 95% CI 2.8-4.0). Other independent predictors were chronic liver (HR 2.8), renal (HR 1.7) and respiratory (HR 1.6) disease, immunosuppressive therapy (HR 1.5), and the need for NIV (HR 1.4) or vasopressor and inotropic support (HR 1.3). No significant difference in mortality was observed between rural/regional and tertiary/metropolitan ICUs, however improved survival was observed in patients admitted to Australian ICUs (n = 6032) compared to those in NZ (n = 415) (HR 0.5 [95% CI 0.4-0.8]). Conclusions:Nearly three-quarters of patients admitted to ICU due to PE remain alive 2 years later. The largest risk factor for late mortality is malignancy, along with other chronic diseases, which is similar to previous studies reporting long-term follow-up of PE survivors outside ICU, however patients who need advanced life supports (NIV, ECMO) were also at greater risk. Limitations of this study include retrospective design, broad heterogeneity in admission criteria across different ICUs due to variation in resources across both countries and lack of data therapies such as intravenous thrombolysis and anticoagulation. Further work is needed to understand if changes to acute management of at-risk patients might improve long-term survival outcomes.

The impact of body mass index on long-term survival after ICU admission due to COVID-19: A retrospective multicentre study

ObjectiveThe impact of obesity on long-term survival after intensive care unit (ICU) admission with severe coronavirus disease 2019 (COVID-19) is unclear. We aimed to quantify the impact of obesity on time to death up to two years in patients admitted to Australian and New Zealand ICUs. DesignRetrospective multicentre study. Setting92 ICUs between 1st January 2020 through to 31st December 2020 in New Zealand and 31st March 2022 in Australia with COVID-19, reported in the Australian and New Zealand Intensive Care Society adult patient database. ParticipantsAll patients with documented height and weight to estimate the body mass index (BMI) were included. Obesity was classified patients according to the World Health Organization recommendations. Interventions and main outcome measuresThe primary outcome was survival time up to two years after ICU admission. The effect of obesity on time to death was assessed using a Cox proportional hazards model. Confounders were acute illness severity, sex, frailty, hospital type and jurisdiction for all patients. ResultsWe examined 2,931 patients; the median BMI was 30.2 (IQR 25.6–36.0) kg/m2. Patients with a BMI ≥30 kg/m2 were younger (median [IQR] age 57.7 [46.2–69.0] vs. 63.0 [50.0–73.6]; p < 0.001) than those with a BMI <30 kg/m2. Most patients (76.6%; 2,244/2,931) were discharged alive after ICU admission. The mortality at two years was highest for BMI categories <18.5 kg/m2 (35.4%) and 18.5–24.9 kg/m2 (31.1%), while lowest for BMI ≥40 kg/m2 (14.5%). After adjusting for confounders and with BMI 18.5–24.9 kg/m2 category as a reference, only the BMI ≥40 kg/m2 category patients had improved survival up to 2 years (hazard ratio = 0.51; 95%CI: 0.34–0.76). ConclusionsThe obesity paradox appears to exist beyond hospital discharge in critically ill patients with COVID-19 admitted in Australian and New Zealand ICUs. A BMI ≥40 kg/m2 was associated with a higher survival time of up to two years.

Measuring the Impact of ICU Strain on Mortality, After-Hours Discharge, Discharge Delay, Interhospital Transfer, and Readmission in Australia With the Activity Index.

ICU resource strain leads to adverse patient outcomes. Simple, well-validated measures of ICU strain are lacking. Our objective was to assess whether the "Activity index," an indicator developed during the COVID-19 pandemic, was a valid measure of ICU strain. Retrospective national registry-based cohort study. One hundred seventy-five public and private hospitals in Australia (June 2020 through March 2022). Two hundred seventy-seven thousand seven hundred thirty-seven adult ICU patients. None. Data from the Australian and New Zealand Intensive Care Society Adult Patient Database were matched to the Critical Health Resources Information System. The mean daily Activity index of each ICU (census total of "patients with 1:1 nursing" + "invasive ventilation" + "renal replacement" + "extracorporeal membrane oxygenation" + "active COVID-19," divided by total staffed ICU beds) during the patient's stay in the ICU was calculated. Patients were categorized as being in the ICU during very quiet (Activity index < 0.1), quiet (0.1 to < 0.6), intermediate (0.6 to < 1.1), busy (1.1 to < 1.6), or very busy time-periods (≥ 1.6). The primary outcome was in-hospital mortality. Secondary outcomes included after-hours discharge from the ICU, readmission to the ICU, interhospital transfer to another ICU, and delay in discharge from the ICU. Median Activity index was 0.87 (interquartile range, 0.40-1.24). Nineteen thousand one hundred seventy-seven patients died (6.9%). In-hospital mortality ranged from 2.4% during very quiet to 10.9% during very busy time-periods. After adjusting for confounders, being in an ICU during time-periods with higher Activity indices, was associated with an increased risk of in-hospital mortality (odds ratio [OR], 1.49; 99% CI, 1.38-1.60), after-hours discharge (OR, 1.27; 99% CI, 1.21-1.34), readmission (OR, 1.18; 99% CI, 1.09-1.28), interhospital transfer (OR, 1.92; 99% CI, 1.72-2.15), and less delay in ICU discharge (OR, 0.58; 99% CI, 0.55-0.62): findings consistent with ICU strain. The Activity index is a simple and valid measure that identifies ICUs in which increasing strain leads to progressively worse patient outcomes.

Mortality data from omission of early thromboprophylaxis in critically ill patients highlights the importance of an individualised diagnosis-related approach

BackgroundVenous thromboembolism (VTE) prophylaxis is effective in reducing VTE events, however, its impact on mortality is unclear. We examined the association between omission of VTE prophylaxis within the first 24 h after intensive care unit (ICU) admission and hospital mortality.MethodsRetrospective analysis of prospectively collected data from the Australian New Zealand Intensive Care Society Adult Patient Database. Data were obtained for adult admissions between 2009 and 2020. Mixed effects logistic regression models were used to evaluate the association between omission of early VTE prophylaxis and hospital mortality.ResultsOf the 1,465,020 ICU admissions, 107,486 (7.3%) did not receive any form of VTE prophylaxis within the first 24 h after ICU admission without documented contraindication. Omission of early VTE prophylaxis was independently associated with 35% increased odds of in-hospital mortality (odds ratios (OR): 1.35; 95% CI: 1.31–1.41). The associations between omission of early VTE prophylaxis and mortality varied by admission diagnosis. In patients diagnosed with stroke (OR: 1.26, 95% CI: 1.05–1.52), cardiac arrest (OR: 1.85, 95% CI: 1.65–2.07) or intracerebral haemorrhage (OR: 1.48, 95% CI: 1.19–1.84), omission of VTE prophylaxis was associated with increased risk of mortality, but not in patients diagnosed with subarachnoid haemorrhage or head injury.ConclusionsOmission of VTE prophylaxis within the first 24 h after ICU admission was independently associated with increased risk of mortality that varied by admission diagnosis. Consideration of early thromboprophylaxis may be required for patients with stroke, cardiac arrest and intracerebral haemorrhage but not in those with subarachnoid haemorrhage or head injury. The findings highlight the importance of individualised diagnosis-related thromboprophylaxis benefit-harm assessments.

Mortality and costs related to severe acute pancreatitis in the intensive care units of Australia and New Zealand (ANZ), 2003–2020

Background and objectiveComprehensive data on the burden of severe acute pancreatitis (SAP) in global intensive care units (ICUs) and trends over time are lacking. Our objective was to compare trends in hospital and ICU mortality, in-hospital and ICU length of stay, and costs related to ICU admission in Australia and New Zealand (ANZ) for SAP. MethodsWe performed a retrospective, observational, cohort study of ICU admissions reported to the ANZ Intensive Care Society Adult Patient Database over three consecutive six-year time periods from 2003 to 2020. Results12,635 patients with SAP from 189 ICUs in ANZ were analysed. No difference in adjusted hospital mortality (11.4% vs 11.5% vs 11.0%, p = 0.85) and ICU mortality rates (7.5% vs 8.0% vs 8.1%, p = 0.73) were noted over the study period. Median length of hospital admission reduced over time (13.9 days in 2003-08, 13.1 days in 2009-14 and 12.5 days in 2015-20; p < 0.01). No difference in length of ICU stay was noted over the study period (p = 0.13). The cost of managing SAP in ANZ ICUs remained constant over the three time periods. ConclusionsIn critically-ill SAP patients in ANZ, no change in mortality has been noted over nearly two decades. There was a slight reduction in hospital stay (1 day), while the length of ICU stay remained unchanged. Given the significant costs related to care of patients with SAP in ICU, these findings highlight the need to prioritise resource allocation for healthcare delivery and targeted clinical research to identify treatments aimed at reducing mortality.

Association Between Preexisting Mental Health Disorders and Adverse Outcomes in Adult Intensive Care Patients: A Data Linkage Study.

Mental illness is known to adversely affect the physical health of patients in primary and acute care settings; however, its impact on critically ill patients is less well studied. This study aimed to determine the prevalence, characteristics, and outcomes of patients admitted to the ICU with a preexisting mental health disorder. A multicenter, retrospective cohort study using linked data from electronic ICU clinical progress notes and the Australia and New Zealand Intensive Care Society Adult Patient Database. All patients admitted to eight Australian adult ICUs in the calendar year 2019. Readmissions within the same hospitalization were excluded. None. Natural language processing techniques were used to classify preexisting mental health disorders in participants based on clinician documentation in electronic ICU clinical progress notes. Sixteen thousand two hundred twenty-eight patients (58% male) were included in the study, of which 5,044 (31.1%) had a documented preexisting mental health disorder. Affective disorders were the most common subtype occurring in 2,633 patients (16.2%), followed by anxiety disorders, occurring in 1,611 patients (9.9%). Mixed-effects regression modeling found patients with a preexisting mental health disorder stayed in ICU 13% longer than other patients (β-coefficient, 0.12; 95% CI, 0.10-0.15) and were more likely to experience invasive ventilation (odds ratio, 1.42; 95% CI, 1.30-1.56). Severity of illness and ICU mortality rates were similar in both groups. Patients with preexisting mental health disorders form a significant subgroup within the ICU. The presence of a preexisting mental health disorder is associated with greater ICU length of stay and higher rates of invasive ventilation, suggesting these patients may have a different clinical trajectory to patients with no mental health history. Further research is needed to better understand the reasons for these adverse outcomes and to develop interventions to better support these patients during and after ICU admission.

The relationship between nursing skill mix and severity of illness of patients admitted in Australian and New Zealand intensive care units

BackgroundCritically ill patients in the intensive care environment require an appropriate nursing workforce to improve quality of care and patient outcomes. However, limited information exists as to the relationship between severity of illness and nursing skill mix in the intensive care. ObjectiveThe aim of this study was to describe the variation in nursing skill mix across different hospital types and to determine if this was associated with severity of illness of critically ill patients admitted to adult intensive care units (ICUs) in Australia and New Zealand. Design & SettingA retrospective cohort study using the Australia and New Zealand Intensive Care Society Adult Patient Database (to provide information on patient demographics, severity of illness, and outcome) and the Critical Care Resources Registry (to provide information on annual nursing staffing levels and hospital type) from July 2014 to June 2020. Four hospital types (metropolitan, private, rural/regional, and tertiary) and three patient groups (elective surgical, emergency surgical, and medical) were examined. Main outcome measureThe main outcome measure was the proportion of critical care specialist registered nurses (RNs) expressed as a percentage of the full-time equivalent (FTE) of total RNs working within each ICU each year, as reported annually to the Critical Care Resources Registry. ResultsData were examined for 184 ICUs in Australia and New Zealand. During the 6-year study period, 770 747 patients were admitted to these ICUs. Across Australia and New Zealand, the median percentage of registered nursing FTE with a critical care qualification for each ICU (n = 184) was 59.1% (interquartile range [IQR] = 48.9–71.6). The percentage FTE of critical care specialist RNs was highest in private [63.7% (IQR = 52.6–78.2)] and tertiary ICUs [58.1% (IQR = 51.2–70.2)], followed by metropolitan ICUs [56.0% (IQR = 44.5–68.9)] with the lowest in rural/regional hospitals [55.9% (IQR = 44.9–70.0)]. In ICUs with higher percentage FTE of critical care specialist RNs, patients had higher severity of illness, most notably in tertiary and private ICUs. This relationship was persistent across all hospital types when examining subgroups of emergency surgical and medical patients and in multivariable analysis after adjusting for the type of hospital and relative percentage of each diagnostic group. ConclusionsIn Australian and New Zealand ICUs, the highest acuity patients are cared for by nursing teams with the highest percentage FTE of critical care specialist RNs. The Australian and New Zealand healthcare system has a critical care nursing workforce which scales to meet the acuity of ICU patients across Australia and New Zealand.

Projecting Future Climate Impact on National Australian Respiratory-Related Intensive Care Unit Demand.

A robust climate-health projection model has the potential to improve health care resource allocation. We aim to explore the relationship between Australian intensive care unit (ICU) demand and various measures of the long-lived large-scale climate and to develop a future nationwide climate-health projection model. We investigated patients admitted to ICUs in Australia between January 2003 and December 2019 who were exposed to long-lived large-scale combined climatic measures of temperature and humidity. We analysed the projected demand for respiratory-related ICU average length of stay (in days) per capita (ICUD/C) with four historical and one future projection dataset. These datasets included: i) Australian and New Zealand Intensive Care Society adult patient database, ii) Socioeconomic Data and Applications Center gridded global historical population, iii) Australian Bureau of Statistics national historical population, iv) Japanese 55-year Reanalysis historical climate (JRA55), and v) the fifth Coupled Model Inter-comparison Project future climate projections. 148,638 patients with respiratory issues required intensive care between 2003 and 2019. The annual growth in the population density-weighted wet-bulb-globe temperature-a combined measure of temperature and humidity-is strongly correlated with the annual per capita growth ICUD/C for respiratory-related conditions (r=0.771; p<0.001). This relationship was applied to develop a model projecting future respiratory-related ICU demand with three possible future Representative Concentration Pathways (RCP). RCP2.6 (lowest carbon emission climate scenario) showed only a 33.4% increase in Australian ICUD/C demand by 2090, while the RCP8.5 (highest carbon emission climate scenario) demonstrated almost two-fold higher demand (66.1%) than RCP2.6 by2090. The annual growth in population density-weighted wet-bulb-globe temperature correlates with the annual growth in Australian ICUD/C for respiratory-related conditions. A model based on possible future climate scenarios can be developed to predict changes in ICU demand in response to CO2 changes over the coming decades.

The prevalence of post-extubation dysphagia in critically ill adults: an Australian data linkage study

Objective: To define the prevalence of dysphagia after endotracheal intubation in critically ill adult patients. Design: A retrospective observational data linkage cohort study using the Australian and New Zealand Intensive Care Society Adult Patient Database and a mandatory government statewide health care administration database. Setting: Private and public intensive care units (ICUs) within Victoria, Australia. Participants: Adult patients who required endotracheal intubation for the purpose of mechanical ventilation within a Victorian ICU between July 2013 and June 2018. Main outcome measures: Presence of dysphagia, aspiration pneumonia, ICU length of stay, hospital length of stay, and cost per episode of care. Results: Endotracheal intubation in the ICU was required for 71 124 patient episodes across the study period. Dysphagia was coded in 7.3% (n = 5203) of those episodes. Patients with dysphagia required longer ICU (median, 154 [interquartile range (IQR), 78-259] v 53 [IQR, 27-107] hours; P < 0.001) and hospital admissions (median, 20 [IQR, 13-30] v 8 [IQR, 5-15] days; P < 0.001), were more likely to develop aspiration pneumonia (17.2% v 5.6%; odds ratio, 3.0; 95% CI, 2.8-3.2; P < 0.001), and the median health care expenditure increased by 93% per episode of care ($73 586 v $38 108; P < 0.001) compared with patients without dysphagia. Conclusions: Post-extubation dysphagia is associated with adverse patient and health care outcomes. Consideration should be given to strategies that support early identification of patients with dysphagia in the ICU to determine if these adverse outcomes can be reduced.

Association between frailty, delirium, and mortality in older critically ill patients: a binational registry study

BackgroundFrailty and delirium are prevalent among older adults admitted to the intensive care unit (ICU) and associated with adverse outcomes; however, their relationships have not been extensively explored. This study examined the association between frailty and mortality and length of hospital stay (LOS) in ICU patients, and whether the associations are mediated or modified by an episode of delirium.MethodsRetrospective analysis of data from the Australian New Zealand Intensive Care Society Adult Patient Database. A total of 149,320 patients aged 65 years or older admitted to 203 participating ICUs between 1 January 2017 and 31 December 2020 who had data for frailty and delirium were included in the analysis.ResultsA total of 41,719 (27.9%) older ICU patients were frail on admission, and 9,179 patients (6.1%) developed delirium during ICU admission. Frail patients had significantly higher odds of in-hospital mortality (OR: 2.15, 95% CI 2.05–2.25), episodes of delirium (OR: 1.86, 95% CI 1.77–1.95), and longer LOS (log-transformed mean difference (MD): 0.24, 95% CI 0.23–0.25). Acute delirium was associated with 32% increased odds of in-hospital mortality (OR: 1.32, 95% CI 1.23–1.43) and longer LOS (MD: 0.54, 95% CI 0.50–0.54). The odds ratios (95% CI) for in-hospital mortality were 1.37 (1.23–1.52), 2.14 (2.04–2.24) and 2.77 (2.51–3.05) for non-frail who developed delirium, frail without delirium, and frail and developed delirium during ICU admission, respectively. There was very small but statistically significant effect of frailty on in-hospital mortality (b for indirect effect: 0.00037, P < 0.001) and LOS (b for indirect effect: 0.019, P < 0.001) mediated through delirium.ConclusionBoth frailty and delirium independently increase the risk of in-hospital mortality and LOS. Acute delirium is more common in frail patients; however, it does not mediate or modify a clinically meaningful amount of the association between frailty and in-hospital mortality and LOS.

Twelve-month mortality outcomes for Indigenous and non-Indigenous people admitted to intensive care units in Australia: a registry-based data linkage study.

To compare longer term (12-month) mortality outcomes for Indigenous and non-Indigenous people admitted to intensive care units (ICUs) in Australia. Retrospective registry-based data linkage cohort study; analysis of all admissions of adults (16 years or older) to Australian ICUs, 1 January 2017 - 31 December 2019, as recorded in the Australian and New Zealand Intensive Care Society (ANZICS) Adult Patient Database (APD), linked using the SLK-581 key to National Death Index data. Unadjusted and adjusted mortality risk, censored at twelve months from the start of index ICU admission. Secondary outcomes were unadjusted and adjusted mortality twelve months from admission to the ICU. The APD recorded 330 712 eligible ICU admissions during 2017-2019 (65% of all ICU admissions registered), of which 11 322 were of Indigenous people (3.4%). Median age at admission was lower for Indigenous patients (51.2 [IQR, 36.7-63.6] years) than for non-Indigenous patients (66.5 [IQR, 52.7-76.1] years). Unadjusted mortality risk was similar for Indigenous and non-Indigenous patients (hazard ratio, 1.01; 95% CI, 0.97-1.06), but was higher for Indigenous patients after adjusting for age, admission diagnosis, illness severity, hospital type, jurisdiction, remoteness and socio-economic status (adjusted hazard ratio, 1.20; 95% CI, 1.14-1.27). Twelve-month mortality was higher for Indigenous than non-Indigenous patients (adjusted odds ratio, 1.24; 95% CI, 1.16-1.33). Twelve-month mortality outcomes are poorer for people admitted to ICUs in Australia than for the general population. Further, after adjusting for age and other factors, survival outcomes are poorer for Indigenous than non-Indigenous people admitted to ICUs. Critical illness may therefore contribute to shorter life expectancy among Indigenous Australians.

The impact of language barriers & interpreters on critical care patient outcomes

BackgroundIn a multicultural society, the impact of language proficiency and interpreter use on critical care patient outcomes is unknown. ObjectiveTo investigate the relationship between English language preference, requirement for an interpreter and in-hospital mortality amongst non-elective intensive care unit (ICU) patients. MethodAdult patients admitted to all 23 public ICUs within the state of Victoria, Australia from July 2007 to June 2018, were extracted from The Australian New Zealand Intensive Care Society Adult Patient Database. De-identified patient data was matched using probabilistic methods and statistical linkage keys to the Victorian Admitted Episodes Database. Patients were classified into one of three groups: ‘English preferred’, ‘English not preferred’ and ‘Interpreter required’. Results126,891 ICU admissions were analysed, of whom 3394 (3%) were in the ‘English not preferred’ group and 6355 (5%) in the ‘Interpreter required’ group. Compared to the ‘English preferred’, both the ‘English not preferred’ and ‘Interpreter required’ groups were older, had more co-morbidities and higher severity of illness scores. In-hospital mortality was 13.1% in the ‘English preferred’ group, 19.6% in the ‘English not preferred’ group and 16.7% in the ‘Interpreter required’ group. However, after adjusting for sex, severity of illness and socio-economic status, the ‘English not preferred’ group remained with a higher risk adjusted mortality (OR 1.21, 95%CI 1.07–1.36, P = 0.002), whereas the ‘Interpreter required’ group had a lower adjusted risk of mortality (OR 0.81, 95%CI 0.74–0.89, P < 0.001). ConclusionBeing identified as having a requirement for an interpreter was associated with improved outcomes for adults admitted to public hospital ICUs in Victoria. Interpreter services should be more readily available in the hospital setting. It is recommended that patients, family members and clinicians actively use interpreter services when English is not the preferred language of an ICU patient.

Comparing the Clinical Frailty Scale and an International Classification of Diseases-10 Modified Frailty Index in Predicting Long-Term Survival in Critically Ill Patients.

IMPORTANCE:The Clinical Frailty Scale (CFS) is the most used frailty measure in intensive care unit (ICU) patients. Recently, the modified frailty index (mFI), derived from 11 comorbidities has also been used. It is unclear to what degree the mFI is a true measure of frailty rather than comorbidity. Furthermore, the mFI cannot be freely obtained outside of specific proprietary databases.OBJECTIVE:To compare the performance of CFS and a recently developed International Classification of Diseases-10 (ICD-10) mFI (ICD-10mFI) as frailty-based predictors of long-term survival for up to 1 year.DESIGN:A retrospective multicentric observational study.SETTING AND PARTICIPANTS:All adult (≥16 yr) critically ill patients with documented CFS scores admitted to sixteen Australian ICUs in the state of Victoria between April 1, 2017 to June 30, 2018 were included. We used probabilistic methods to match de-identified ICU admission episodes listed in the Australia and New Zealand Intensive Care Society Adult Patient Database with the Victorian Admission Episode Dataset and the Victorian Death Index via the Victorian Data Linkage Centre.MAIN OUTCOMES AND MEASURES:The primary outcome was the longest available survival following ICU admission. We compared CFS and ICD-10mFI as primary outcome predictors, after adjusting for key confounders.RESULTS:The CFS and ICD-10mFI were compared in 7,001 ICU patients. The proportion of patients categorized as frail was greater with the CFS than with the ICD-10mFI (18.9% [n = 1,323] vs. 8.8% [n = 616]; p < 0.001). The median (IQR) follow-up time was 165 (82–276) days. The CFS predicted long-term survival up to 6 months after adjusting for confounders (hazard ratio [HR] = 1.26, 95% CI, 1.21–1.31), whereas ICD-10mFI did not (HR = 1.04, 95% CI, 0.98–1.10). The ICD-10mFI weakly correlated with the CFS (Spearman’s rho = 0.22) but had a poor agreement (kappa = 0.06). The ICD-10mFI more strongly correlated with the Charlson comorbidity index (Spearman’s rho 0.30) than CFS (Spearman’s rho = 0.25) (p < 0.001).CONCLUSIONS:CFS, but not ICD-10mFI, predicted long-term survival in ICU patients. ICD-10mFI correlated with co-morbidities more than CFS. These findings suggest that CFS and ICD-10mFI are not equivalent.RELEVANCE:CFS and ICD-10mFI are not equivalent in screening for frailty in critically ill patients and therefore ICD-10mFI in its current form should not be used.

Impact of frailty on clinical outcomes in patients with and without COVID-19 pneumonitis admitted to intensive care units in Australia and New Zealand: a retrospective registry data analysis

BackgroundIt is unclear if the impact of frailty on mortality differs between patients with viral pneumonitis due to COVID-19 or other causes. We aimed to determine if a difference exists between patients with and without COVID-19 pneumonitis.MethodsThis multicentre, retrospective, cohort study using the Australian and New Zealand Intensive Care Society Adult Patient Database included patients aged ≥ 16 years admitted to 153 ICUs between 01/012020 and 12/31/2021 with admission diagnostic codes for viral pneumonia or acute respiratory distress syndrome, and Clinical Frailty Scale (CFS). The primary outcome was hospital mortality.ResultsA total of 4620 patients were studied, and 3077 (66.6%) had COVID-19. The patients with COVID-19 were younger (median [IQR] 57.0 [44.7–68.3] vs. 66.1 [52.0–76.2]; p < 0.001) and less frail (median [IQR] CFS 3 [2–4] vs. 4 [3–5]; p < 0.001) than non-COVID-19 patients. The overall hospital mortality was similar between the patients with and without COVID-19 (14.7% vs. 14.9%; p = 0.82). Frailty alone as a predictor of mortality showed only moderate discrimination in differentiating survivors from those who died but was similar between patients with and without COVID-19 (AUROC 0.68 vs. 0.66; p = 0.42). Increasing frailty scores were associated with hospital mortality, after adjusting for Australian and New Zealand Risk of Death score and sex. However, the effect of frailty was similar in patients with and without COVID-19 (OR = 1.29; 95% CI: 1.19–1.41 vs. OR = 1.24; 95% CI: 1.11–1.37).ConclusionThe presence of frailty was an independent risk factor for mortality. However, the impact of frailty on outcomes was similar in COVID-19 patients compared to other causes of viral pneumonitis.Graphical

Vascular surgery patients in intensive care: a bi-national cohort study over 15 years.

To describe the characteristics and outcomes of patients admitted to Intensive Care following vascular surgery, and their subsequent usage of Intensive Care resources, over a 15-year period in Australia and New Zealand. This was a retrospective, bi-national study of 69 676 adult patients admitted to 179 Intensive Care Unit (ICUs) following vascular surgery between January 2005 and December 2019, using the Australian and New Zealand Intensive Care Society Adult Patient Database. The proportion of ICU bed days used by vascular surgery patients decreased during the study period from 3.6% in 2005 to 2.9% in 2019 (P< 0.001). The cohort had a median age of 73 years, and were most frequently admitted after a carotid endarterectomy (22%) or elective open aneurysm repair (20%). A total of 5.2% of patients did not survive to discharge. Mean annual adjusted mortality decreased during the study period from 6.1% in 2005 to 3.7% in 2019 (P< 0.001). Multiple factors were associated with higher mortality, including gender, hospital case volume and hospital type. Between 2005 and 2019 survival for vascular surgery patients requiring ICU admission in Australia and New Zealand improved. During the same time the proportion of ICU bed days used by these patients decreased.

Outcomes of Prolonged ICU Stay for Patients Undergoing Cardiac Surgery in Australia and New Zealand

To determine the effect of intensive care unit (ICU) length of stay (LOS) on hospital mortality and non-home discharge for patients undergoing cardiac surgery over a 16-year period in Australia and New Zealand. A retrospective, multicenter cohort study covering the period January 1, 2004 to December 31, 2019. One hundred one hospitals in Australia and New Zealand that submitted data to the Australia New Zealand Intensive Care Society Adult Patient Database. Adult patients (aged >18) who underwent coronary artery bypass grafting, valve surgery, or combined valve+coronary artery surgery. None. The authors analyzed 252,948 cardiac surgical patients from 101 hospitals, with a median age of 68.3 years (IQR 60-75.5), of whom 74.2% (187,632 of 252,948) were male patients. A U-shaped relationship was observed between ICU LOS and hospital mortality, with significantly elevated mortality at short (<20 hours) and long (>5 days) ICU LOS, which persisted after adjustment for illness severity and across clinically important subgroups (odds ratio for mortality with ICU LOS >5 days=3.21, 95% CI 2.88-3.58, p < 0.001). Prolonged duration of ICU LOS after cardiac surgery is associated with increased hospital mortality in a U-shaped relationship. An ICU LOS >5 days should be considered a meaningful definition for prolonged ICU stay after cardiac surgery.

Intensive care admissions following rapid response team reviews in patients with COVID-19 in Australia

Objectives: To evaluate the epidemiology of rapid response team (RRT) reviews that led to intensive care unit (ICU) admissions, and to evaluate the frequency of in-hospital cardiac arrests (IHCAs) among ICU patients with confirmed coronavirus disease 2019 (COVID-19) in Australia. Design: Multicentre, retrospective cohort study. Setting: 48 public and private ICUs in Australia. Participants: All adults (aged ≥ 16 years) with confirmed COVID-19 admitted to participating ICUs between 25 January and 31 October 2020, as part of SPRINT-SARI (Short PeRiod IncideNce sTudy of Severe Acute Respiratory Infection) Australia, which were linked with ICUs contributing to the Australian and New Zealand Intensive Care Society Adult Patient Database (ANZICS APD). Main outcome measures and results: Of the 413 critically ill patients with COVID-19 who were analysed, 48.2% (199/413) were admitted from the ward and 30.5% (126/413) were admitted to the ICU following an RRT review. Patients admitted following an RRT review had higher Acute Physiology and Chronic Health Evaluation (APACHE) scores, fewer days from symptom onset to hospitalisation (median, 5.4 [interquartile range (IQR), 3.2-7.6] v 7.1 days [IQR, 4.1-9.8]; P < 0.001) and longer hospitalisations (median, 18 [IQR, 11-33] v 13 days [IQR, 7-24]; P < 0.001) compared with those not admitted via an RRT review. Admissions following RRT review comprised 60.3% (120/199) of all ward-based admissions. Overall, IHCA occurred in 1.9% (8/413) of ICU patients with COVID-19, and most IHCAs (6/8, 75%) occurred during ICU admission. There were no differences in IHCA rates or in ICU or hospital mortality rates based on whether a patient had a prior RRT review or not. Conclusions: This study found that RRT reviews were a common way for deteriorating ward patients with COVID-19 to be admitted to the ICU, and that IHCA was rare among ICU patients with COVID-19.