Albumin use in patients with septic shock-Post-hoc analyses of an international randomised fluid trial.

BACKGROUND: Albumin administration is suggested in patients with sepsis and septic shock who have received large volumes of crystalloids. Given lack of firm evidence, clinical practice variation may exist. To address this, we investigated if patient characteristics or trial site were associated with albumin use in septic shock. METHODS: We conducted a post-hoc study of the CLASSIC international, randomised clinical trial of fluid volumes in septic shock. Associations between selected baseline variables and trial site with albumin use during ICU stay were assessed in Cox models considering death, ICU discharge, and loss-to-follow-up as competing events. Baseline variables were first assessed individually, adjusted for treatment allocation (restrictive vs. standard IV fluid), and then adjusted for allocation and the other baseline variables. Site was assessed in a model adjusted for allocation and baseline variables. RESULTS: We analysed 1541 of 1554 patients randomised in CLASSIC (99.2%). During ICU stay, 36.3% of patients in the restrictive-fluid group and 52.6% in the standard-fluid group received albumin. Gastrointestinal focus of infection and higher doses of norepinephrine were most strongly associated with albumin use (subgroup with highest quartile of norepinephrine doses, hazard ratio (HR) 2.58, 95% CI 1.89 to 3.53). HRs for associations between site and albumin use ranged from 0.11 (95% CI 0.05 to 0.26) to 1.70 (95% CI 1.06 to 2.74); test for overall effect of site: p < .001. CONCLUSIONS: In adults with septic shock, gastrointestinal focus of infection and higher doses of norepinephrine at baseline were associated with albumin use, which also varied substantially between sites.

Restrictive versus standard IV fluid therapy in adult ICU patients with septic shock-Bayesian analyses of the CLASSIC trial.

BACKGROUND: The CLASSIC trial assessed the effects of restrictive versus standard intravenous (IV) fluid therapy in adult intensive care unit (ICU) patients with septic shock. This pre-planned study provides a probabilistic interpretation and evaluates heterogeneity in treatment effects (HTE). METHODS: We analysed mortality, serious adverse events (SAEs), serious adverse reactions (SARs) and days alive without life-support within 90 days using Bayesian models with weakly informative priors. HTE on mortality was assessed according to five baseline variables: disease severity, vasopressor dose, lactate levels, creatinine values and IV fluid volumes given before randomisation. RESULTS: The absolute difference in mortality was 0.2%-points (95% credible interval: -5.0 to 5.4; 47% posterior probability of benefit [risk difference <0.0%-points]) with restrictive IV fluid. The posterior probabilities of benefits with restrictive IV fluid were 72% for SAEs, 52% for SARs and 61% for days alive without life-support. The posterior probabilities of no clinically important differences (absolute risk difference ≤2%-points) between the groups were 56% for mortality, 49% for SAEs, 90% for SARs and 38% for days alive without life-support. There was 97% probability of HTE for previous IV fluid volumes analysed continuously, that is, potentially relatively lower mortality of restrictive IV fluids with higher previous IV fluids. No substantial evidence of HTE was found in the other analyses. CONCLUSION: We could not rule out clinically important effects of restrictive IV fluid therapy on mortality, SAEs or days alive without life-support, but substantial effects on SARs were unlikely. IV fluids given before randomisation might interact with IV fluid strategy.

Effects of IV fluid restriction according to site-specific intensity of standard fluid treatment-protocol.

BACKGROUND: Variation in usual practice in fluid trials assessing lower versus higher volumes may affect overall comparisons. To address this, we will evaluate the effects of heterogeneity in treatment intensity in the Conservative versus Liberal Approach to Fluid Therapy of Septic Shock in Intensive Care trial. This will reflect the effects of differences in site-specific intensities of standard fluid treatment due to local practice preferences while considering participant characteristics. METHODS: We will assess the effects of heterogeneity in treatment intensity across one primary (all-cause mortality) and three secondary outcomes (serious adverse events or reactions, days alive without life support and days alive out of hospital) after 90 days. We will classify sites based on the site-specific intensity of standard fluid treatment, defined as the mean differences in observed versus predicted intravenous fluid volumes in the first 24 h in the standard-fluid group while accounting for differences in participant characteristics. Predictions will be made using a machine learning model including 22 baseline predictors using the extreme gradient boosting algorithm. Subsequently, sites will be grouped into fluid treatment intensity subgroups containing at least 100 participants each. Subgroups differences will be assessed using hierarchical Bayesian regression models with weakly informative priors. We will present the full posterior distributions of relative (risk ratios and ratios of means) and absolute differences (risk differences and mean differences) in each subgroup. DISCUSSION: This study will provide data on the effects of heterogeneity in treatment intensity while accounting for patient characteristics in critically ill adult patients with septic shock. REGISTRATIONS: The European Clinical Trials Database (EudraCT): 2018-000404-42, ClinicalTrials. gov: NCT03668236.

Albumin administration in septic shock-Protocol for post-hoc analyses of data from a multicentre RCT.

BACKGROUND: Intravenous (IV) albumin is suggested for patients with septic shock who have received large amounts of IV crystalloids; a conditional recommendation based on moderate certainty of evidence. Clinical variation in the administration of IV albumin in septic shock may exist according to patient characteristics and location. METHODS: This is a protocol and statistical analysis plan for a post-hoc secondary study of the Conservative versus Liberal Approach to Fluid Therapy of Septic Shock in Intensive Care (CLASSIC) RCT of 1554 adult ICU patients with septic shock. We will assess if specific baseline characteristics or trial site are associated with the administration of IV albumin during ICU stay using Cox models with competing events. All models will be adjusted for the treatment allocation in CLASSIC (restrictive vs. standard IV fluid), and all analyses will consider competing events (death, ICU discharge and loss-to-follow-up). We will present results as hazard ratios with 95% confidence intervals and p-values for the associations of baseline characteristics or site with IV albumin administration. Between-group differences (interactions) will be assessed using p-values from likelihood ratio tests. All results will be considered exploratory only. DISCUSSION: This secondary study of the CLASSIC RCT may yield important insight into potential practice variation in the administration of albumin in septic shock.

Higher vs Lower Doses of Dexamethasone in Patients with COVID-19 and Severe Hypoxia (COVID STEROID 2) trial: Protocol for a secondary Bayesian analysis.

BACKGROUND: Coronavirus disease 2019 (COVID-19) can lead to severe hypoxic respiratory failure and death. Corticosteroids decrease mortality in severely or critically ill patients with COVID-19. However, the optimal dose remains unresolved. The ongoing randomised COVID STEROID 2 trial investigates the effects of higher vs lower doses of dexamethasone (12 vs 6 mg intravenously daily for up to 10 days) in 1,000 adult patients with COVID-19 and severe hypoxia. METHODS: This protocol outlines the rationale and statistical methods for a secondary, pre-planned Bayesian analysis of the primary outcome (days alive without life support at day 28) and all secondary outcomes registered up to day 90. We will use hurdle-negative binomial models to estimate the mean number of days alive without life support in each group and present results as mean differences and incidence rate ratios with 95% credibility intervals (CrIs). Additional count outcomes will be analysed similarly and binary outcomes will be analysed using logistic regression models with results presented as probabilities, relative risks and risk differences with 95% CrIs. We will present probabilities of any benefit/harm, clinically important benefit/harm and probabilities of effects smaller than pre-defined clinically minimally important differences for all outcomes analysed. Analyses will be adjusted for stratification variables and conducted using weakly informative priors supplemented by sensitivity analyses using sceptic priors. DISCUSSION: This secondary, pre-planned Bayesian analysis will supplement the primary, conventional analysis and may help clinicians, researchers and policymakers interpret the results of the COVID STEROID 2 trial while avoiding arbitrarily dichotomised interpretations of the results. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04509973; EudraCT: 2020-003363-25.

Low-dose hydrocortisone in patients with COVID-19 and severe hypoxia: The COVID STEROID randomised, placebo-controlled trial.

BACKGROUND: In the early phase of the pandemic, some guidelines recommended the use of corticosteroids for critically ill patients with COVID-19, whereas others recommended against the use despite lack of firm evidence of either benefit or harm. In the COVID STEROID trial, we aimed to assess the effects of low-dose hydrocortisone on patient-centred outcomes in adults with COVID-19 and severe hypoxia. METHODS: In this multicentre, parallel-group, placebo-controlled, blinded, centrally randomised, stratified clinical trial, we randomly assigned adults with confirmed COVID-19 and severe hypoxia (use of mechanical ventilation or supplementary oxygen with a flow of at least 10 L/min) to either hydrocortisone (200 mg/d) vs a matching placebo for 7 days or until hospital discharge. The primary outcome was the number of days alive without life support at day 28 after randomisation. RESULTS: The trial was terminated early when 30 out of 1000 participants had been enrolled because of external evidence indicating benefit from corticosteroids in severe COVID-19. At day 28, the median number of days alive without life support in the hydrocortisone vs placebo group were 7 vs 10 (adjusted mean difference: -1.1 days, 95% CI -9.5 to 7.3, P = .79); mortality was 6/16 vs 2/14; and the number of serious adverse reactions 1/16 vs 0/14. CONCLUSIONS: In this trial of adults with COVID-19 and severe hypoxia, we were unable to provide precise estimates of the benefits and harms of hydrocortisone as compared with placebo as only 3% of the planned sample size were enrolled. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04348305. European Union Drug Regulation Authorities Clinical Trials (EudraCT) Database: 2020-001395-15.

Low-dose hydrocortisone in patients with COVID-19 and severe hypoxia (COVID STEROID) trial-Protocol and statistical analysis plan.

INTRODUCTION: Severe acute respiratory syndrome coronavirus-2 has caused a pandemic of coronavirus disease (COVID-19) with many patients developing hypoxic respiratory failure. Corticosteroids reduce the time on mechanical ventilation, length of stay in the intensive care unit and potentially also mortality in similar patient populations. However, corticosteroids have undesirable effects, including longer time to viral clearance. Clinical equipoise on the use of corticosteroids for COVID-19 exists. METHODS: The COVID STEROID trial is an international, randomised, stratified, blinded clinical trial. We will allocate 1000 adult patients with COVID-19 receiving ≥10 L/min of oxygen or on mechanical ventilation to intravenous hydrocortisone 200 mg daily vs placebo (0.9% saline) for 7 days. The primary outcome is days alive without life support (ie mechanical ventilation, circulatory support, and renal replacement therapy) at day 28. Secondary outcomes are serious adverse reactions at day 14; days alive without life support at day 90; days alive and out of hospital at day 90; all-cause mortality at day 28, day 90, and 1 year; and health-related quality of life at 1 year. We will conduct the statistical analyses according to this protocol, including interim analyses for every 250 patients followed for 28 days. The primary outcome will be compared using the Kryger Jensen and Lange test in the intention to treat population and reported as differences in means and medians with 95% confidence intervals. DISCUSSION: The COVID STEROID trial will provide important evidence to guide the use of corticosteroids in COVID-19 and severe hypoxia.

Influenza and associated co-infections in critically ill immunosuppressed patients.

BACKGROUND: It is unclear whether influenza infection and associated co-infection are associated with patient-important outcomes in critically ill immunocompromised patients with acute respiratory failure. METHODS: Preplanned secondary analysis of EFRAIM, a prospective cohort study of 68 hospitals in 16 countries. We included 1611 patients aged 18 years or older with non-AIDS-related immunocompromise, who were admitted to the ICU with acute hypoxemic respiratory failure. The main exposure of interest was influenza infection status. The primary outcome of interest was all-cause hospital mortality, and secondary outcomes ICU length of stay (LOS) and 90-day mortality. RESULTS: Influenza infection status was categorized into four groups: patients with influenza alone (n = 95, 5.8%), patients with influenza plus pulmonary co-infection (n = 58, 3.6%), patients with non-influenza pulmonary infection (n = 820, 50.9%), and patients without pulmonary infection (n = 638, 39.6%). Influenza infection status was associated with a requirement for intubation and with LOS in ICU (P < 0.001). Patients with influenza plus co-infection had the highest rates of intubation and longest ICU LOS. On crude analysis, influenza infection status was associated with ICU mortality (P < 0.001) but not hospital mortality (P = 0.09). Patients with influenza plus co-infection and patients with non-influenza infection alone had similar ICU mortality (41% and 37% respectively) that was higher than patients with influenza alone or those without infection (33% and 26% respectively). A propensity score-matched analysis did not show a difference in hospital mortality attributable to influenza infection (OR = 1.01, 95%CI 0.90-1.13, P = 0.85). Age, severity scores, ARDS, and performance status were all associated with ICU, hospital, and 90-day mortality. CONCLUSIONS: Category of infectious etiology of respiratory failure (influenza, non-influenza, influenza plus co-infection, and non-infectious) was associated with ICU but not hospital mortality. In a propensity score-matched analysis, influenza infection was not associated with the primary outcome of hospital mortality. Overall, influenza infection alone may not be an independent risk factor for hospital mortality in immunosuppressed patients.

Time to onset of gastrointestinal bleeding in the SUP-ICU trial: A pre-planned substudy.

BACKGROUND: The aetiology and risk factors for clinically important gastrointestinal bleeding (CIB) in adult ICU patients may differ according to the onset of CIB, which could affect the balance between benefits and harms of stress ulcer prophylaxis (SUP). METHODS: We assessed the time to CIB in the Stress Ulcer Prophylaxis in the Intensive Care Unit (SUP-ICU) trial. We assessed if associations between baseline characteristics including allocation to SUP and CIB changed during time in the ICU, specifically in the later (after day 2) compared to the earlier (first 2 days) period, using Cox models adjusted for SAPS II and allocation to SUP. Additionally, we described baseline characteristics and CIB episodes stratified by earlier/later/no CIB and 90-day mortality status. RESULTS: Clinically important gastrointestinal bleeding occurred in 110/3291 (3.3%) patients after a median of 6 (interquartile range 2-13) days; 25.5% of the episodes occurred early. Higher SAPS II was consistently associated with increased risk of CIB (hazard ratio (HR) 1.03, 95% confidence interval (CI) 1.01-1.05 in the earlier period vs HR 1.02, 95% CI 1.01-1.03 in the later period; P = .37); university hospital admission was associated with decreased risk of earlier CIB (HR 0.30, 95% CI 0.14-0.63); this significantly increased in the later period (to HR 0.85, 95% CI 0.53-1.37; P = .02). Patients with later compared to earlier CIB received more transfusions and had more diagnostic/therapeutic procedures for CIB. CONCLUSIONS: Clinically important gastrointestinal bleeding mostly occurred more than 2 days after randomization. University hospital admission was associated with significantly decreased risk of CIB in the earlier period only.

Conservative vs liberal fluid therapy in septic shock (CLASSIC) trial-Protocol and statistical analysis plan.

INTRODUCTION: Intravenous (IV) fluid is a key intervention in the management of septic shock. The benefits and harms of lower versus higher fluid volumes are unknown and thus clinical equipoise exists. We describe the protocol and detailed statistical analysis plan for the conservative versus liberal approach to fluid therapy of septic shock in the Intensive Care (CLASSIC) trial. The aim of the CLASSIC trial is to assess benefits and harms of IV fluid restriction versus standard care in adult intensive care unit (ICU) patients with septic shock. METHODS: CLASSIC trial is an investigator-initiated, international, randomised, stratified, and analyst-blinded trial. We will allocate 1554 adult patients with septic shock, who are planned to be or are admitted to an ICU, to IV fluid restriction versus standard care. The primary outcome is mortality at day 90. Secondary outcomes are serious adverse events (SAEs), serious adverse reactions (SARs), days alive at day 90 without life support, days alive and out of the hospital at day 90 and mortality, health-related quality of life (HRQoL), and cognitive function at 1 year. We will conduct the statistical analyses according to a pre-defined statistical analysis plan, including three interim analyses. For the primary analysis, we will use logistic regression adjusted for the stratification variables comparing the two interventions in the intention-to-treat (ITT) population. DISCUSSION: The CLASSIC trial results will provide important evidence to guide clinicians' choice regarding the IV fluid therapy in adults with septic shock.

Protocol for a systematic review and meta-analysis assessing conservative versus liberal intravenous fluid administration in patients with sepsis or septic shock at risk of fluid overload.

INTRODUCTION: Intravenous crystalloid fluid resuscitation forms a crucial part of the early intervention bundle for sepsis and septic shock, with the Surviving Sepsis Campaign guidelines recommending a 30 mL/kg fluid bolus within the first hour. Compliance with this suggested target varies in patients with comorbidities such as congestive heart failure, chronic kidney disease and cirrhosis due to concerns regarding iatrogenic fluid overload. However, it remains unclear whether resuscitation with higher fluid volumes puts them at greater risk of adverse outcomes. Thus, this systematic review will synthesise evidence from existing studies to assess the effects of a conservative as compared with a liberal approach to fluid resuscitation in patients at greater perceived risk of fluid overload due to comorbid conditions. METHODS AND ANALYSIS: This protocol was registered on PROSPERO and has been drafted following the checklist of Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. We will search MEDLINE, MEDLINE Epub Ahead of Print and In-Process, In-Data-Review & Other Non-Indexed Citations, Embase, Embase Classic, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Web of Science Core Collection, CINAHL Complete and ClinicalTrials.gov. A preliminary search of these databases was performed from their inception to 30 August 2022. The risk of bias and random errors will be assessed using the revised Cochrane risk-of-bias tool for randomised clinical trials and the Newcastle-Ottawa Scale for case-control and cohort studies. If a sufficient number of comparable studies are identified, we will perform a meta-analysis applying random effects model. We will investigate heterogeneity using a combination of visual inspection of the funnel plot as well as the Egger's test. ETHICS AND DISSEMINATION: No ethics approval is required for this study since no original data will be collected. The findings will be disseminated through peer-reviewed publication and conference presentation. PROSPERO REGISTRATION NUMBER: CRD42022348181.

Long-term effects of restriction of intravenous fluid in adult ICU patients with septic shock.

PURPOSE: To assess long-term outcomes of restrictive versus standard intravenous (IV) fluid therapy in adult intensive care unit (ICU) patients with septic shock included in the European Conservative versus Liberal Approach to Fluid Therapy in Septic Shock in Intensive Care (CLASSIC) trial. METHODS: We conducted the pre-planned analyses of mortality, health-related quality of life (HRQoL) using EuroQol (EQ)-5D-5L index values and EQ visual analogue scale (VAS), and cognitive function using Mini Montreal Cognitive Assessment (Mini MoCA) test at 1 year. Deceased patients were assigned numerical zero for HRQoL as a state equal to death and zero for cognitive function outcomes as worst possible score, and we used multiple imputation for missing data on HRQoL and cognitive function. RESULTS: Among 1554 randomized patients, we obtained 1-year data on mortality in 97.9% of patients, HRQoL in 91.3%, and cognitive function in 86.3%. One-year mortality was 385/746 (51.3%) in the restrictive-fluid group versus 383/767 (49.9%) in the standard-fluid group, absolute risk difference 1.5%-points [99% confidence interval (CI) - 4.8 to 7.8]. Mean differences were 0.00 (99% CI - 0.06 to 0.05) for EQ-5D-5L index values, - 0.65 for EQ VAS (- 5.40 to 4.08), and - 0.14 for Mini MoCA (- 1.59 to 1.14) for the restrictive-fluid group versus the standard-fluid group. The results for survivors only were similar in both groups. CONCLUSIONS: Among adult ICU patients with septic shock, restrictive versus standard IV fluid therapy resulted in similar survival, HRQoL, and cognitive function at 1 year, but clinically important differences could not be ruled out.

Long-term outcomes of dexamethasone 12 mg versus 6 mg in patients with COVID-19 and severe hypoxaemia.

PURPOSE: We assessed long-term outcomes of dexamethasone 12 mg versus 6 mg given daily for up to 10 days in patients with coronavirus disease 2019 (COVID-19) and severe hypoxaemia. METHODS: We assessed 180-day mortality and health-related quality of life (HRQoL) using EuroQoL (EQ)-5D-5L index values and EQ visual analogue scale (VAS) in the international, stratified, blinded COVID STEROID 2 trial, which randomised 1000 adults with confirmed COVID-19 receiving at least 10 L/min of oxygen or mechanical ventilation in 26 hospitals in Europe and India. In the HRQoL analyses, higher values indicated better outcomes, and deceased patients were given a score of zero. RESULTS: We obtained vital status at 180 days for 963 of 982 patients (98.1%) in the intention-to-treat population, EQ-5D-5L index value data for 922 (93.9%) and EQ VAS data for 924 (94.1%). At 180 days, 164 of 486 patients (33.7%) had died in the 12 mg group versus 184 of 477 (38.6%) in the 6 mg group [adjusted risk difference - 4.3%; 99% confidence interval (CI) - 11.7-3.0; relative risk 0.89; 0.72-1.09; P = 0.13]. The adjusted mean differences between the 12 mg and the 6 mg groups in EQ-5D-5L index values were 0.06 (99% CI - 0.01 to 0.12; P = 0.10) and in EQ VAS scores 4 (- 3 to 10; P = 0.22). CONCLUSION: Among patients with COVID-19 and severe hypoxaemia, dexamethasone 12 mg compared with 6 mg did not result in statistically significant improvements in mortality or HRQoL at 180 days, but the results were most compatible with benefit from the higher dose.

Dexamethasone 12 mg versus 6 mg for patients with COVID-19 and severe hypoxaemia: a pre-planned, secondary Bayesian analysis of the COVID STEROID 2 trial.

PURPOSE: We compared dexamethasone 12 versus 6 mg daily for up to 10 days in patients with coronavirus disease 2019 (COVID-19) and severe hypoxaemia in the international, randomised, blinded COVID STEROID 2 trial. In the primary, conventional analyses, the predefined statistical significance thresholds were not reached. We conducted a pre-planned Bayesian analysis to facilitate probabilistic interpretation. METHODS: We analysed outcome data within 90 days in the intention-to-treat population (data available in 967 to 982 patients) using Bayesian models with various sensitivity analyses. Results are presented as median posterior probabilities with 95% credible intervals (CrIs) and probabilities of different effect sizes with 12 mg dexamethasone. RESULTS: The adjusted mean difference on days alive without life support at day 28 (primary outcome) was 1.3 days (95% CrI -0.3 to 2.9; 94.2% probability of benefit). Adjusted relative risks and probabilities of benefit on serious adverse reactions was 0.85 (0.63 to 1.16; 84.1%) and on mortality 0.87 (0.73 to 1.03; 94.8%) at day 28 and 0.88 (0.75 to 1.02; 95.1%) at day 90. Probabilities of benefit on days alive without life support and days alive out of hospital at day 90 were 85 and 95.7%, respectively. Results were largely consistent across sensitivity analyses, with relatively low probabilities of clinically important harm with 12 mg on all outcomes in all analyses. CONCLUSION: We found high probabilities of benefit and low probabilities of clinically important harm with dexamethasone 12 mg versus 6 mg daily in patients with COVID-19 and severe hypoxaemia on all outcomes up to 90 days.

Lower vs Higher Fluid Volumes During Initial Management of Sepsis: A Systematic Review With Meta-Analysis and Trial Sequential Analysis.

OBJECTIVE: IV fluids are recommended during the initial management of sepsis, but the quality of evidence is low, and clinical equipoise exists. We aimed to assess patient-important benefits and harms of lower vs higher fluid volumes in adult patients with sepsis. METHODS: We conducted a systematic review with meta-analysis and trial sequential analysis (TSA) of randomized clinical trials of IV fluid volume separation in adult patients with sepsis. We adhered to our published protocol; the Cochrane handbook; the Preferred Reporting Items for Systematic Reviews and Meta-Analyses; and the Grading of Recommendations Assessment, Development and Evaluation statements. The primary outcomes were all-cause mortality, serious adverse events (SAEs), and quality of life. RESULTS: We included nine trials (n = 637); all were published after 2015 and had an overall high risk of bias. We found no statistically significant difference between lower vs higher fluid volumes in all-cause mortality (relative risk [RR], 0.87; 95% CI, 0.69-1.10; I2 = 0%; TSA-adjusted CI, 0.34-2.22) or SAEs (RR, 0.91; 95% CI, 0.78-1.05; I2 = 0%; TSA-adjusted CI, 0.68-1.21). No trials reported on quality of life. We did not find differences in the secondary or exploratory outcomes. The quality of evidence was very low across all outcomes. CONCLUSIONS: In this systematic review, we found very low quantity and quality of evidence supporting the decision on the volumes of IV fluid therapy in adults with sepsis. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03668236; URL: www.clinicaltrials.gov.

Acute hypoxemic respiratory failure in immunocompromised patients: the Efraim multinational prospective cohort study.

BACKGROUND: In immunocompromised patients with acute hypoxemic respiratory failure (ARF), initial management aims primarily to avoid invasive mechanical ventilation (IMV). METHODS: To assess the impact of initial management on IMV and mortality rates, we performed a multinational observational prospective cohort study in 16 countries (68 centers). RESULTS: A total of 1611 patients were enrolled (hematological malignancies 51.9%, solid tumors 35.2%, systemic diseases 17.3%, and solid organ transplantation 8.8%). The main ARF etiologies were bacterial (29.5%), viral (15.4%), and fungal infections (14.7%), or undetermined (13.2%). On admission, 915 (56.8%) patients were not intubated. They received standard oxygen (N = 496, 53.9%), high-flow oxygen (HFNC, N = 187, 20.3%), noninvasive ventilation (NIV, N = 153, 17.2%), and NIV + HFNC (N = 79, 8.6%). Factors associated with IMV included age (hazard ratio = 0.92/year, 95% CI 0.86-0.99), day-1 SOFA (1.09/point, 1.06-1.13), day-1 PaO2/FiO2 (1.47, 1.05-2.07), ARF etiology (Pneumocystis jirovecii pneumonia (2.11, 1.42-3.14), invasive pulmonary aspergillosis (1.85, 1.21-2.85), and undetermined cause (1.46, 1.09-1.98). After propensity score matching, HFNC, but not NIV, had an effect on IMV rate (HR = 0.77, 95% CI 0.59-1.00, p = 0.05). ICU, hospital, and day-90 mortality rates were 32.4, 44.1, and 56.4%, respectively. Factors independently associated with hospital mortality included age (odds ratio = 1.18/year, 1.09-1.27), direct admission to the ICU (0.69, 0.54-0.87), day-1 SOFA excluding respiratory score (1.12/point, 1.08-1.16), PaO2/FiO2 < 100 (1.60, 1.03-2.48), and undetermined ARF etiology (1.43, 1.04-1.97). Initial oxygenation strategy did not affect mortality; however, IMV was associated with mortality, the odds ratio depending on IMV conditions: NIV + HFNC failure (2.31, 1.09-4.91), first-line IMV (2.55, 1.94-3.29), NIV failure (3.65, 2.05-6.53), standard oxygen failure (4.16, 2.91-5.93), and HFNC failure (5.54, 3.27-9.38). CONCLUSION: HFNC has an effect on intubation but not on mortality rates. Failure to identify ARF etiology is associated with higher rates of both intubation and mortality. This suggests that in addition to selecting the appropriate oxygenation device, clinicians should strive to identify the etiology of ARF.