Two Weeks Versus One Week of Maximal Patient-Intensivist Continuity for Adult Medical Intensive Care Patients: A Two-Center Target Trial Emulation.

OBJECTIVES: To compare outcomes for 2 weeks vs. 1 week of maximal patient-intensivist continuity in the ICU. DESIGN: Retrospective cohort study. SETTING: Two U.S. urban, teaching, medical ICUs where intensivists were scheduled for 2-week service blocks: site A was in the Midwest and site B was in the Northeast. PATIENTS: Patients 18 years old or older admitted to a study ICU between March 1, 2017, and February 28, 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We applied target trial emulation to compare admission during an intensivist's first week (as a proxy for 2 wk of maximal continuity) vs. admission during their second week (as a proxy for 1 wk of maximal continuity). Outcomes included hospital mortality, ICU length of stay, and, for mechanically ventilated patients, duration of ventilation. Exploratory outcomes included imaging, echocardiogram, and consultation orders. We used inverse probability weighting to adjust for baseline differences and random-effects meta-analysis to calculate overall effect estimates. Among 2571 patients, 1254 were admitted during an intensivist's first week and 1317 were admitted during a second week. At sites A and B, hospital mortality rates were 25.8% and 24.2%, median ICU length of stay were 4 and 2 days, and median mechanical ventilation durations were 3 and 3 days, respectively. There were no differences in adjusted mortality (odds ratio [OR], 1.01 [95% CI, 0.96-1.06]) or ICU length of stay (-0.25 d [-0.82 d to +0.32 d]) for 2 weeks vs. 1 week of maximal continuity. Among mechanically ventilated patients, there were no differences in adjusted mortality (OR, 1.00 [0.87-1.16]), ICU length of stay (+0.06 d [-0.78 d to +0.91 d]), or duration of mechanical ventilation (+0.37 d [-0.46 d to +1.21 d]) for 2 weeks vs. 1 week of maximal continuity. CONCLUSIONS: Two weeks of maximal patient-intensivist continuity was not associated with differences in clinical outcomes compared with 1 week in two medical ICUs.

Variation in Sedative and Analgesic Use During the COVID-19 Pandemic and Associated Outcomes.

BACKGROUND: Providing analgesia and sedation is an essential component of caring for many mechanically ventilated patients. The selection of analgesic and sedative medications during the COVID-19 pandemic, and the impact of these sedation practices on patient outcomes, remain incompletely characterized. RESEARCH QUESTION: What were the hospital patterns of analgesic and sedative use for patients with COVID-19 who received mechanical ventilation (MV), and what differences in clinical patient outcomes were observed across prevailing sedation practices? STUDY DESIGN AND METHODS: We conducted an observational cohort study of hospitalized adults who received MV for COVID-19 from February 2020 through April 2021 within the Society of Critical Care Medicine Discovery Viral Infection and Respiratory Illness Universal Study (VIRUS) COVID-19 Registry. To describe common sedation practices, we used hierarchical clustering to group hospitals based on the percentage of patients who received various analgesic and sedative medications. We then used multivariable regression models to evaluate the association between hospital analgesia and sedation cluster and duration of MV (with a placement of death [POD] approach to account for competing risks). RESULTS: We identified 1,313 adults across 35 hospitals admitted with COVID-19 who received MV. Two clusters of analgesia and sedation practices were identified. Cluster 1 hospitals generally administered opioids and propofol with occasional use of additional sedatives (eg, benzodiazepines, alpha-agonists, and ketamine); cluster 2 hospitals predominantly used opioids and benzodiazepines without other sedatives. As compared with patients in cluster 2, patients admitted to cluster 1 hospitals underwent a shorter adjusted median duration of MV with POD (ß-estimate, -5.9; 95% CI, -11.2 to -0.6; P = .03). INTERPRETATION: Patients who received MV for COVID-19 in hospitals that prioritized opioids and propofol for analgesia and sedation experienced shorter adjusted median duration of MV with POD as compared with patients who received MV in hospitals that primarily used opioids and benzodiazepines.

A novel measure to summarize blood transfusion practice during critical illness.

BACKGROUND: Large-scale observational studies have summarized transfusion practice using traditional measures of central tendency (e.g., the mean hemoglobin concentration at the time of transfusion). However, the mean hemoglobin concentration fails to identify specific hemoglobin concentration thresholds that drive practice. In the following brief report, we propose a novel measure of "practice discontinuity" that identifies specific practice-defining hemoglobin thresholds. STUDY DESIGN AND METHODS: We used the PINC AI Database (2016-2022) to identify adult patients admitted to an intensive care unit with at least one hemoglobin concentration measurement. For each day that hemoglobin was measured, we identified whether the patient received a red blood cell transfusion using hospital charge codes. We defined the "practice discontinuity" measure as the hemoglobin concentration at which there was the largest increase in transfusion use going from a higher to an incrementally lower hemoglobin concentration. We also calculated the mean and median pretransfusion hemoglobin concentrations. RESULTS: We identified 1,298,367 patients and 4,905,839 patient-days for inclusion. RBC transfusion occurred in a total of 530,654 (10.8%) patient-days. The overall pre-transfusion mean and median hemoglobin concentrations were 8.4 and 8.0 g/dL, respectively. The practice discontinuity measure identified 7.0 g/dL as the hemoglobin concentration at which transfusion use increased the most, from 46.6% of patient-days at a concentration of 7.0 g/dL to 74.8% of patient-days at a concentration of 6.9 g/dL. DISCUSSION: We propose that future studies of red blood cell transfusion practice consider inclusion of the practice discontinuity measure to more fully summarize clinical practice.

Variation in Use of Medications for Opioid Use Disorder in Critically Ill Patients Across the United States.

OBJECTIVES: To describe practice patterns surrounding the use of medications to treat opioid use disorder (MOUD) in critically ill patients. DESIGN: Retrospective, multicenter, observational study using the Premier AI Healthcare Database. SETTING: The study was conducted in U.S. ICUs. PATIENTS: Adult (≥ 18 yr old) patients with a history of opioid use disorder (OUD) admitted to an ICU between 2016 and 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 108,189 ICU patients (658 hospitals) with a history of OUD, 20,508 patients (19.0%) received MOUD. Of patients receiving MOUD, 13,745 (67.0%) received methadone, 2,950 (14.4%) received buprenorphine, and 4,227 (20.6%) received buprenorphine/naloxone. MOUD use occurred in 37.9% of patients who received invasive mechanical ventilation. The median day of MOUD initiation was hospital day 2 (interquartile range [IQR] 1-3) and the median duration of MOUD use was 4 days (IQR 2-8). MOUD use per hospital was highly variable (median 16.0%; IQR 10-24; range, 0-70.0%); admitting hospital explained 8.9% of variation in MOUD use. A primary admitting diagnosis of unintentional poisoning (aOR 0.41; 95% CI, 0.38-0.45), presence of an additional substance use disorder (aOR 0.66; 95% CI, 0.64-0.68), and factors indicating greater severity of illness were associated with reduced odds of receiving MOUD in the ICU. CONCLUSIONS: In a large multicenter, retrospective study, there was large variation in the use of MOUD among ICU patients with a history of OUD. These results inform future studies seeking to optimize the approach to MOUD use during critical illness.

Effectiveness of Fludrocortisone Plus Hydrocortisone versus Hydrocortisone Alone in Septic Shock: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials.

Rationale: The use of hydrocortisone in adult patients with septic shock is controversial, and the effectiveness of adding fludrocortisone to hydrocortisone remains uncertain. Objectives: To assess the comparative effectiveness and safety of fludrocortisone plus hydrocortisone, hydrocortisone alone, and placebo or usual care in adults with septic shock. Methods: A systematic review and a Bayesian network meta-analysis of peer-reviewed randomized trials were conducted. The primary outcome was all-cause mortality at last follow-up. Treatment effects are presented as relative risks (RRs) with 95% credible intervals (CrIs). Placebo or usual care was the reference treatment. Measurements and Main Results: Among 7,553 references, we included 17 trials (7,688 patients). All-cause mortality at last follow-up was lowest with fludrocortisone plus hydrocortisone (RR, 0.85; 95% CrI, 0.72-0.99; 98.3% probability of superiority, moderate-certainty evidence), followed by hydrocortisone alone (RR, 0.97; 95% CrI, 0.87-1.07; 73.1% probability of superiority, low-certainty evidence). The comparison of fludrocortisone plus hydrocortisone versus hydrocortisone alone was based primarily on indirect evidence (only two trials with direct evidence). Fludrocortisone plus hydrocortisone was associated with a 12% lower risk of all-cause mortality compared with hydrocortisone alone (RR, 0.88; 95% CrI, 0.74-1.03; 94.2% probability of superiority, moderate-certainty evidence). Conclusions: In adult patients with septic shock, fludrocortisone plus hydrocortisone was associated with lower risk of all-cause mortality at last follow-up than placebo and hydrocortisone alone. The scarcity of head-to-head trials comparing fludrocortisone plus hydrocortisone versus hydrocortisone alone led our network meta-analysis to rely primarily on indirect evidence for this comparison. Although we undertook several sensitivity analyses and assessments, these findings should be considered while also acknowledging the heterogeneity of included trials.

Comparative Effectiveness of Mepolizumab, Benralizumab and Dupilumab among Patients with Difficult-to-Control Asthma.

Rationale The comparative effectiveness of biologics used as add-on therapy in the management of difficult-to-control asthma is unclear. Objective To compare the effectiveness of dupilumab, mepolizumab and benralizumab among patients with difficult-to-control asthma. Methods Retrospective multicenter cohort study of adult patients with difficult-to-control asthma started on dupilumab, mepolizumab or benralizumab from a multicenter electronic health record and claims-based database between October 19, 2018 and September 30, 2022. Propensity score matching was used to minimize bias from non-randomized treatment assignment; prespecified alpha level was set at 0.017 to account for three primary comparisons. The exposure of interest was new initiation of dupilumab, benralizumab or mepolizumab. The primary outcome was the rate of asthma exacerbation in the year following initiation of biologic therapy modeled using a negative binomial approach. Results Among 893,668 patients with asthma who were prescribed an inhaled corticosteroid and were at least 12 years old, (65% female, mean age 49), 3,943 started dupilumab, 1,902 started benralizumab, and 2,012 started mepolizumab without an alternative indication for biologic therapy. After matching, there were 1,805 patients in each group for comparisons between dupilumab and benralizumab, 1,865 for comparisons between dupilumab and mepolizumab, and 1,721 for comparisons between mepolizumab and benralizumab. For all pairwise comparisons, covariates were well balanced after matching (all standardized mean differences <0.1). Patients initiating dupilumab had a significantly lower rate of asthma exacerbations (1.07/year) compared to benralizumab (1.47/year) with a rate ratio of 0.73 [95% confidence interval (CI) 0.63-0.85] and also had a significantly lower rate of asthma exacerbations compared to mepolizumab (1.04/year compared to 1.45/year) with a rate ratio of 0.72 [0.62-0.84]. There was no statistically significant difference in the rate of asthma exacerbations between mepolizumab (1.40/year) and benralizumab (1.41/year) with a rate ratio of 1.00 [CI 0.85-1.17]. Conclusions In patients with difficult-to-control asthma newly initiated on biologic therapy, dupilumab was associated with a decreased rate of asthma exacerbations in the year after initiation as compared with mepolizumab or benralizumab.

An Update on Management of Adult Patients with Acute Respiratory Distress Syndrome: An Official American Thoracic Society Clinical Practice Guideline.

Background: This document updates previously published Clinical Practice Guidelines for the management of patients with acute respiratory distress syndrome (ARDS), incorporating new evidence addressing the use of corticosteroids, venovenous extracorporeal membrane oxygenation, neuromuscular blocking agents, and positive end-expiratory pressure (PEEP). Methods: We summarized evidence addressing four "PICO questions" (patient, intervention, comparison, and outcome). A multidisciplinary panel with expertise in ARDS used the Grading of Recommendations, Assessment, Development, and Evaluation framework to develop clinical recommendations. Results: We suggest the use of: 1) corticosteroids for patients with ARDS (conditional recommendation, moderate certainty of evidence), 2) venovenous extracorporeal membrane oxygenation in selected patients with severe ARDS (conditional recommendation, low certainty of evidence), 3) neuromuscular blockers in patients with early severe ARDS (conditional recommendation, low certainty of evidence), and 4) higher PEEP without lung recruitment maneuvers as opposed to lower PEEP in patients with moderate to severe ARDS (conditional recommendation, low to moderate certainty), and 5) we recommend against using prolonged lung recruitment maneuvers in patients with moderate to severe ARDS (strong recommendation, moderate certainty). Conclusions: We provide updated evidence-based recommendations for the management of ARDS. Individual patient and illness characteristics should be factored into clinical decision making and implementation of these recommendations while additional evidence is generated from much-needed clinical trials.

Practice Patterns and Outcomes of Potassium Repletion Thresholds during Critical Illness.

Rationale: Potassium repletion is common in critically ill patients. However, practice patterns and outcomes related to different intensive care unit (ICU) potassium repletion strategies are unclear. Objectives: 1) Describe potassium repletion practices in critically ill adults; 2) compare the effectiveness of potassium repletion strategies; and 3) compare effectiveness and safety of specific potassium repletion thresholds on patient outcomes. Methods: This was a retrospective analysis of the PINC AI Healthcare Database (2016-2022), including all critically ill adults admitted to an ICU on Hospital Day 1 and with a serum potassium concentration measured on Hospital Day 2. We determined the frequency of potassium repletion (any formulation) at each measured serum potassium concentration in each ICU, then classified ICUs as having threshold-based (a large increase in potassium repletion rates at a specific serum potassium concentration) or probabilistic (linear relationship between serum concentration and the repletion probability) patterns of repletion. Between patients in threshold-based and probabilistic repletion ICUs, we compared outcomes (primary outcome: potassium repletion frequency). We reported unadjusted percentages per exposure group and the adjusted odds ratios (from hierarchical regression models) for each outcome. Among patients in threshold-based ICUs with the most common repletion thresholds (3.5 mEq/L and 4.0 mEq/L), we conducted regression discontinuity analyses to examine the effectiveness of potassium repletion at each potassium threshold. Results: We included 190,490 patients in 88 ICUs; 35.0% received at least one dose of potassium on the same calendar day. Rates of potassium repletion were similar between 22 threshold-based strategy ICUs (33.5%) and 22 probabilistic strategy ICUs (36.4%). There was no difference in the adjusted risk of potassium repletion between patients admitted to threshold-based strategy ICUs versus probabilistic strategy ICUs (adjusted odds ratio, 1.09; 95% confidence interval [CI], 0.76-1.57). In regression discontinuity analysis, crossing the 3.5 mEq/L threshold from high to low potassium levels resulted in a 39.1% (95% CI, 23.7-42.4) absolute increase in potassium repletion but no change in other outcomes. Similarly, crossing the 4.0 mEq/L threshold resulted in a 36.4% (95% CI, 22.4-42.2) absolute increase in potassium repletion but no change in other outcomes. Conclusions: Potassium repletion is common in critically ill patients and occurs over a narrow range of "normal" potassium levels (3.5-4.0 mEq/L); use of a threshold-based repletion strategy to guide potassium repletion in ICU patients is not associated with clinically meaningful differences in outcomes.

Patient Outcomes After Long-Term Acute Care Hospital Closures.

Importance: Long-term acute care hospitals (LTCHs) are common sites of postacute care for patients recovering from severe respiratory failure requiring mechanical ventilation (MV). However, federal payment reform led to the closure of many LTCHs in the US, and it is unclear how closure of LTCHs may have affected upstream care patterns at short-stay hospitals and overall patient outcomes. Objective: To estimate the association between LTCH closures and short-stay hospital care patterns and patient outcomes. Design, Setting, and Participants: This retrospective, national, matched cohort study used difference-in-differences analysis to compare outcomes at short-stay hospitals reliant on LTCHs that closed during 2012 to 2018 with outcomes at control hospitals. Data were obtained from the Medicare Provider Analysis and Review File, 2011 to 2019. Participants included Medicare fee-for-service beneficiaries aged 66 years and older receiving MV for at least 96 hours in an intensive care unit (ie, patients at-risk for prolonged MV) and the subgroup also receiving a tracheostomy (ie, receiving prolonged MV). Data were analyzed from October 2022 to June 2023. Exposure: Admission to closure-affected hospitals, defined as those discharging at least 60% of patients receiving a tracheostomy to LTCHs that subsequently closed, vs control hospitals. Main Outcomes and Measures: Upstream hospital care pattern outcomes were short-stay hospital do-not-resuscitate orders, palliative care delivery, tracheostomy placement, and discharge disposition. Patient outcomes included hospital length of stay, days alive and institution free within 90 days, spending per days alive within 90 days, and 90-day mortality. Results: Between 2011 and 2019, 99 454 patients receiving MV for at least 96 hours at 1261 hospitals were discharged to 459 LTCHs; 84 LTCHs closed. Difference-in-differences analysis included 8404 patients (mean age, 76.2 [7.2] years; 4419 [52.6%] men) admitted to 45 closure-affected hospitals and 45 matched-control hospitals. LTCH closure was associated with decreased LTCH transfer rates (difference, -5.1 [95% CI -8.2 to -2.0] percentage points) and decreased spending-per-days-alive (difference, -$8701.58 [95% CI, -$13 323.56 to -$4079.60]). In the subgroup of patients receiving a tracheostomy, there was additionally an increase in do-not-resuscitate rates (difference, 10.3 [95% CI, 4.2 to 16.3] percentage points) and transfer to skilled nursing facilities (difference, 10.0 [95% CI, 4.2 to 15.8] percentage points). There was no significant association of closure with 90-day mortality. Conclusions and Relevance: In this cohort study, LTCH closure was associated with changes in discharge patterns in patients receiving mechanical ventilation for at least 96 hours and advanced directive decisions in the subgroup receiving a tracheostomy, without change in mortality. Further studies are needed to understand how LTCH availability may be associated with other important outcomes, including functional outcomes and patient and family satisfaction.

Effect of Respiratory Viral Panel Adoption on Antibiotic Use in Ventilated Patients.

Rationale: Rapid respiratory viral panel (RVP) testing has become widely used to aid in the diagnosis and treatment of acute respiratory failure. However, the impact of RVP on antibiotic stewardship in critically ill patients is unclear. Objectives: To assess if adoption of RVP testing at hospitals was associated with changes in antibiotic duration in intensive care unit patients receiving invasive mechanical ventilation. Methods: With data from the Premier Inc. database from 2016 to 2019, we used interrupted time series with multivariable hierarchical linear regression models to quantify trends in outcomes for 31,644 patients in the 12 months before RVP adoption, the level change in outcomes at the time of RVP adoption (estimand of interest), and changes in outcome trends in the 12 months after RVP adoption. Results: Hospital adoption of RVP testing (n = 62,603) was associated with a decrease in days of antibiotics by 0.5 days (95% confidence interval, -0.8, -0.1) in the first month after adoption. There was also a significant decrease in the risk of Clostridioides difficile infection by 0.9% (95% confidence interval, -1.6, -0.3). There were no significant changes in other outcomes, including hospitalization costs, hospital length of stay, or rates of ventilator-associated pneumonia. Conclusions: Hospital adoption of RVP testing was associated with modest reductions in both antibiotic duration and risk of C. difficile infection among intensive care unit patients with acute respiratory failure and suspected infection.

Discharge Disposition and Loss of Independence Among Survivors of COVID-19 Admitted to Intensive Care: Results From the SCCM Discovery Viral Infection and Respiratory Illness Universal Study (VIRUS).

OBJECTIVES: To describe incidence and risk factors of loss of previous independent living through nonhome discharge or discharge home with health assistance in survivors of intensive care unit (ICU) admission for coronavirus disease 2019 (COVID-19). DESIGN: Multicenter observational study including patients admitted to the ICU from January 2020 till June 30, 2021. HYPOTHESIS: We hypothesized that there is a high risk of nonhome discharge in patients surviving ICU admission due to COVID-19. SETTING: Data were included from 306 hospitals in 28 countries participating in the SCCM Discovery Viral Infection and Respiratory Illness Universal Study COVID-19 registry. PATIENTS: Previously independently living adult ICU survivors of COVID-19. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was nonhome discharge. Secondary outcome was the requirement of health assistance among patients who were discharged home. Out of 10 820 patients, 7101 (66%) were discharged alive; 3791 (53%) of these survivors lost their previous independent living status, out of those 2071 (29%) through nonhome discharge, and 1720 (24%) through discharge home requiring health assistance. In adjusted analyses, loss of independence on discharge among survivors was predicted by patient age ≥ 65 years (adjusted odds ratio [aOR] 2.78, 95% confidence interval [CI] 2.47-3.14, P < .0001), former and current smoking status (aOR 1.25, 95% CI 1.08-1.46, P = .003 and 1.60 (95% CI 1.18-2.16), P = .003, respectively), substance use disorder (aOR 1.52, 95% CI 1.12-2.06, P = .007), requirement for mechanical ventilation (aOR 4.17, 95% CI 3.69-4.71, P < .0001), prone positioning (aOR 1.19, 95% CI 1.03-1.38, P = .02), and requirement for extracorporeal membrane oxygenation (aOR 2.28, 95% CI 1.55-3.34, P < .0001). CONCLUSIONS: More than half of ICU survivors hospitalized for COVID-19 are unable to return to independent living status, thereby imposing a significant secondary strain on health care systems worldwide.

Comparison of Propylthiouracil vs Methimazole for Thyroid Storm in Critically Ill Patients.

Importance: Thyroid storm is the most severe form of thyrotoxicosis, with high mortality, and is treated with propylthiouracil and methimazole. Some guidelines recommend propylthiouracil over methimazole, although the difference in outcomes associated with each treatment is unclear. Objective: To compare outcomes associated with use of propylthiouracil vs methimazole for the treatment of thyroid storm. Design, Setting, and Participants: This comparative effectiveness study comprised a large, multicenter, US-based cohort from the Premier Healthcare Database between January 1, 2016, and December 31, 2020. It included 1383 adult patients admitted to intensive or intermediate care units with a diagnosis of thyroid storm per International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes and treated with either propylthiouracil or methimazole. Analyses were conducted from July 2022 to February 2023. Exposure: Patients received either propylthiouracil or methimazole for treatment of thyroid storm. Exposure was assigned based on the initial thionamide administered. Main Outcomes and Measures: The primary outcome was the adjusted risk difference of in-hospital death or discharge to hospice between patients treated with propylthiouracil and those treated with methimazole, assessed by targeted maximum likelihood estimation. Results: A total of 1383 patients (656 [47.4%] treated with propylthiouracil; mean [SD] age, 45 [16] years; 473 women [72.1%]; and 727 [52.6%] treated with methimazole; mean [SD] age, 45 [16] years; 520 women [71.5%]) were included in the study. The standardized mean difference for age was 0.056, and the standardized mean difference for sex was 0.013. The primary composite outcome occurred in 7.4% of of patients (102 of 1383; 95% CI, 6.0%-8.8%). A total of 8.5% (56 of 656; 95% CI, 6.4%-10.7%) of patients who initiated propylthiouracil and 6.3% (46 of 727; 95% CI, 4.6%-8.1%) who initiated methimazole died in the hospital (adjusted risk difference, 0.6% [95% CI, -1.8% to 3.0%]; P = .64). There were no significant differences in duration of organ support, total hospitalization costs, or rates of adverse events between the 2 treatment groups. Conclusion and Relevance: In this comparative effectiveness study of a multicenter cohort of adult patients with thyroid storm, no significant differences were found in mortality or adverse events in patients who were treated with propylthiouracil or methimazole. Thus, current guidelines recommending propylthiouracil over methimazole for treatment of thyroid storm may merit reevaluation.

Hospital-level variation in practices and outcomes for patients with severe acute exacerbations of idiopathic pulmonary fibrosis: a retrospective multicentre cohort study.

BACKGROUND: In the absence of evidence-based strategies to improve patient outcomes, the management of patients with severe idiopathic pulmonary fibrosis (IPF) exacerbations may vary widely across centres. We assessed between-hospital variation in practices and mortality for patients with severe IPF exacerbations. METHODS: Using the Premier Healthcare Database from 1 October 2015 to 31 December 2020, we identified patients admitted to intensive care unit (ICU) or intermediate care unit with an IPF exacerbation. We assessed idiosyncratic, between-hospital variation in ICU practices (invasive mechanical ventilation (IMV), non-invasive mechanical ventilation (NIMV), corticosteroid use, and immunosuppressive and/or antioxidant use) and hospital mortality by determining median risk-adjusted hospital rates and intraclass correlation coefficients (ICCs) from hierarchical multivariable regression models. A priori, an ICC>15% was deemed 'high variation'. RESULTS: We identified 5256 critically ill patients with a severe IPF exacerbation at 385 US hospitals. Hospital median risk-adjusted rates of practices were: IMV (14% (IQR: 8.3%-26%)), NIMV (42% (31%-54%)), corticosteroid use (89% (84%-93%)), and immunosuppressive and/or antioxidant use (3.3% (1.9%-5.8%)). Model ICCs were: IMV (19% (95% CI: 18% to 21%)), NIMV (15% (13% to 16%)), corticosteroid use (9.8% (8.3% to 11%)), and immunosuppressive and/or antioxidant use (8.5% (7.1% to 9.9%)). The median risk-adjusted hospital mortality was 16% (IQR: 11%-24%) with an ICC of 7.5% (95% CI: 6.2% to 8.9%). INTERPRETATION: We observed high variation in the use of IMV and NIMV, and less variation in corticosteroid and immunosuppressant and/or antioxidant use among patients hospitalised with severe IPF exacerbations. Further research is needed to guide the decisions surrounding initiation of IMV and role of NIMV and to understand the effectiveness of corticosteroids among patients with severe IPF exacerbations.