Oxygen-Saturation Targets for Critically Ill Adults Receiving Mechanical Ventilation.

BACKGROUND: Invasive mechanical ventilation in critically ill adults involves adjusting the fraction of inspired oxygen to maintain arterial oxygen saturation. The oxygen-saturation target that will optimize clinical outcomes in this patient population remains unknown. METHODS: In a pragmatic, cluster-randomized, cluster-crossover trial conducted in the emergency department and medical intensive care unit at an academic center, we assigned adults who were receiving mechanical ventilation to a lower target for oxygen saturation as measured by pulse oximetry (Spo2) (90%; goal range, 88 to 92%), an intermediate target (94%; goal range, 92 to 96%), or a higher target (98%; goal range, 96 to 100%). The primary outcome was the number of days alive and free of mechanical ventilation (ventilator-free days) through day 28. The secondary outcome was death by day 28, with data censored at hospital discharge. RESULTS: A total of 2541 patients were included in the primary analysis. The median number of ventilator-free days was 20 (interquartile range, 0 to 25) in the lower-target group, 21 (interquartile range, 0 to 25) in the intermediate-target group, and 21 (interquartile range, 0 to 26) in the higher-target group (P = 0.81). In-hospital death by day 28 occurred in 281 of the 808 patients (34.8%) in the lower-target group, 292 of the 859 patients (34.0%) in the intermediate-target group, and 290 of the 874 patients (33.2%) in the higher-target group. The incidences of cardiac arrest, arrhythmia, myocardial infarction, stroke, and pneumothorax were similar in the three groups. CONCLUSIONS: Among critically ill adults receiving invasive mechanical ventilation, the number of ventilator-free days did not differ among groups in which a lower, intermediate, or higher Spo2 target was used. (Supported by the National Heart, Lung, and Blood Institute and others; PILOT ClinicalTrials.gov number, NCT03537937.).

Oxygen-Saturation Targets and Cognitive and Functional Outcomes in Mechanically Ventilated Adults.

Rationale: Among mechanically ventilated critically ill adults, the PILOT (Pragmatic Investigation of Optimal Oxygen Targets) trial demonstrated no difference in ventilator-free days among lower, intermediate, and higher oxygen-saturation targets. The effects on long-term cognition and related outcomes are unknown.Objectives: To compare the effects of lower (90% [range, 88-92%]), intermediate (94% [range, 92-96%]), and higher (98% [range, 96-100%]) oxygen-saturation targets on long-term outcomes.Methods: Twelve months after enrollment in the PILOT trial, blinded neuropsychological raters conducted assessments of cognition, disability, employment status, and quality of life. The primary outcome was global cognition as measured using the Telephone Montreal Cognitive Assessment. In a subset of patients, an expanded neuropsychological battery measured executive function, attention, immediate and delayed memory, verbal fluency, and abstraction.Measurements and Main Results: A total of 501 patients completed follow-up, including 142 in the lower, 186 in the intermediate, and 173 in the higher oxygen target groups. Median (interquartile range) peripheral oxygen saturation values in the lower, intermediate, and higher target groups were 94% (91-96%), 95% (93-97%), and 97% (95-99%), respectively. Telephone Montreal Cognitive Assessment score did not differ between lower and intermediate (adjusted odds ratio [OR], 1.36 [95% confidence interval (CI), 0.92-2.00]), intermediate and higher (adjusted OR, 0.90 [95% CI, 0.62-1.29]), or higher and lower (adjusted OR, 1.22 [95% CI, 0.83-1.79]) target groups. There was also no difference in individual cognitive domains, disability, employment, or quality of life.Conclusions: Among mechanically ventilated critically ill adults who completed follow-up at 12 months, oxygen-saturation targets were not associated with cognition or related outcomes.

A New Global Definition of Acute Respiratory Distress Syndrome.

Background: Since publication of the 2012 Berlin definition of acute respiratory distress syndrome (ARDS), several developments have supported the need for an expansion of the definition, including the use of high-flow nasal oxygen, the expansion of the use of pulse oximetry in place of arterial blood gases, the use of ultrasound for chest imaging, and the need for applicability in resource-limited settings. Methods: A consensus conference of 32 critical care ARDS experts was convened, had six virtual meetings (June 2021 to March 2022), and subsequently obtained input from members of several critical care societies. The goal was to develop a definition that would 1) identify patients with the currently accepted conceptual framework for ARDS, 2) facilitate rapid ARDS diagnosis for clinical care and research, 3) be applicable in resource-limited settings, 4) be useful for testing specific therapies, and 5) be practical for communication to patients and caregivers. Results: The committee made four main recommendations: 1) include high-flow nasal oxygen with a minimum flow rate of ⩾30 L/min; 2) use PaO2:FiO2 ⩽ 300 mm Hg or oxygen saturation as measured by pulse oximetry SpO2:FiO2 ⩽ 315 (if oxygen saturation as measured by pulse oximetry is ⩽97%) to identify hypoxemia; 3) retain bilateral opacities for imaging criteria but add ultrasound as an imaging modality, especially in resource-limited areas; and 4) in resource-limited settings, do not require positive end-expiratory pressure, oxygen flow rate, or specific respiratory support devices. Conclusions: We propose a new global definition of ARDS that builds on the Berlin definition. The recommendations also identify areas for future research, including the need for prospective assessments of the feasibility, reliability, and prognostic validity of the proposed global definition.

Dexmedetomidine or Propofol for Sedation in Mechanically Ventilated Adults with Sepsis.

BACKGROUND: Guidelines currently recommend targeting light sedation with dexmedetomidine or propofol for adults receiving mechanical ventilation. Differences exist between these sedatives in arousability, immunity, and inflammation. Whether they affect outcomes differentially in mechanically ventilated adults with sepsis undergoing light sedation is unknown. METHODS: In a multicenter, double-blind trial, we randomly assigned mechanically ventilated adults with sepsis to receive dexmedetomidine (0.2 to 1.5 µg per kilogram of body weight per hour) or propofol (5 to 50 µg per kilogram per minute), with doses adjusted by bedside nurses to achieve target sedation goals set by clinicians according to the Richmond Agitation-Sedation Scale (RASS, on which scores range from -5 [unresponsive] to +4 [combative]). The primary end point was days alive without delirium or coma during the 14-day intervention period. Secondary end points were ventilator-free days at 28 days, death at 90 days, and age-adjusted total score on the Telephone Interview for Cognitive Status questionnaire (TICS-T; scores range from 0 to 100, with a mean of 50±10 and lower scores indicating worse cognition) at 6 months. RESULTS: Of 432 patients who underwent randomization, 422 were assigned to receive a trial drug and were included in the analyses - 214 patients received dexmedetomidine at a median dose of 0.27 µg per kilogram per hour, and 208 received propofol at a median dose of 10.21 µg per kilogram per minute. The median duration of receipt of the trial drugs was 3.0 days (interquartile range, 2.0 to 6.0), and the median RASS score was -2.0 (interquartile range, -3.0 to -1.0). We found no difference between dexmedetomidine and propofol in the number of days alive without delirium or coma (adjusted median, 10.7 vs. 10.8 days; odds ratio, 0.96; 95% confidence interval [CI], 0.74 to 1.26), ventilator-free days (adjusted median, 23.7 vs. 24.0 days; odds ratio, 0.98; 95% CI, 0.63 to 1.51), death at 90 days (38% vs. 39%; hazard ratio, 1.06; 95% CI, 0.74 to 1.52), or TICS-T score at 6 months (adjusted median score, 40.9 vs. 41.4; odds ratio, 0.94; 95% CI, 0.66 to 1.33). Safety end points were similar in the two groups. CONCLUSIONS: Among mechanically ventilated adults with sepsis who were being treated with recommended light-sedation approaches, outcomes in patients who received dexmedetomidine did not differ from outcomes in those who received propofol. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT01739933.).

Blood Pressure Management After Endovascular Therapy for Acute Ischemic Stroke: The BEST-II Randomized Clinical Trial.

Importance: The effects of moderate systolic blood pressure (SBP) lowering after successful recanalization with endovascular therapy for acute ischemic stroke are uncertain. Objective: To determine the futility of lower SBP targets after endovascular therapy (<140 mm Hg or 160 mm Hg) compared with a higher target (≤180 mm Hg). Design, Setting, and Participants: Randomized, open-label, blinded end point, phase 2, futility clinical trial that enrolled 120 patients with acute ischemic stroke who had undergone successful endovascular therapy at 3 US comprehensive stroke centers from January 2020 to March 2022 (final follow-up, June 2022). Intervention: After undergoing endovascular therapy, participants were randomized to 1 of 3 SBP targets: 40 to less than 140 mm Hg, 40 to less than 160 mm Hg, and 40 to 180 mm Hg or less (guideline recommended) group, initiated within 60 minutes of recanalization and maintained for 24 hours. Main Outcomes and Measures: Prespecified multiple primary outcomes for the primary futility analysis were follow-up infarct volume measured at 36 (±12) hours and utility-weighted modified Rankin Scale (mRS) score (range, 0 [worst] to 1 [best]) at 90 (±14) days. Linear regression models were used to test the harm-futility boundaries of a 10-mL increase (slope of 0.5) in the follow-up infarct volume or a 0.10 decrease (slope of -0.005) in the utility-weighted mRS score with each 20-mm Hg SBP target reduction after endovascular therapy (1-sided α = .05). Additional prespecified futility criterion was a less than 25% predicted probability of success for a future 2-group, superiority trial comparing SBP targets of the low- and mid-thresholds with the high-threshold (maximum sample size, 1500 with respect to the utility-weighted mRS score outcome). Results: Among 120 patients randomized (mean [SD] age, 69.6 [14.5] years; 69 females [58%]), 113 (94.2%) completed the trial. The mean follow-up infarct volume was 32.4 mL (95% CI, 18.0 to 46.7 mL) for the less than 140-mm Hg group, 50.7 mL (95% CI, 33.7 to 67.7 mL), for the less than 160-mm Hg group, and 46.4 mL (95% CI, 24.5 to 68.2 mL) for the 180-mm Hg or less group. The mean utility-weighted mRS score was 0.51 (95% CI, 0.38 to 0.63) for the less than 140-mm Hg group, 0.47 (95% CI, 0.35 to 0.60) for the less than 160-mm Hg group, and 0.58 (95% CI, 0.46 to 0.71) for the high-target group. The slope of the follow-up infarct volume for each mm Hg decrease in the SBP target, adjusted for the baseline Alberta Stroke Program Early CT score, was -0.29 (95% CI, -0.81 to ∞; futility P = .99). The slope of the utility-weighted mRS score for each mm Hg decrease in the SBP target after endovascular therapy, adjusted for baseline utility-weighted mRS score, was -0.0019 (95% CI, -∞ to 0.0017; futility P = .93). Comparing the high-target SBP group with the lower-target groups, the predicted probability of success for a future trial was 25% for the less than 140-mm Hg group and 14% for the 160-mm Hg group. Conclusions and Relevance: Among patients with acute ischemic stroke, lower SBP targets less than either 140 mm Hg or 160 mm Hg after successful endovascular therapy did not meet prespecified criteria for futility compared with an SBP target of 180 mm Hg or less. However, the findings suggested a low probability of benefit from lower SBP targets after endovascular therapy if tested in a future larger trial. Trial Registration: ClinicalTrials.gov Identifier: NCT04116112.

Renin-Angiotensin System Modulation With Synthetic Angiotensin (1-7) and Angiotensin II Type 1 Receptor-Biased Ligand in Adults With COVID-19: Two Randomized Clinical Trials.

Importance: Preclinical models suggest dysregulation of the renin-angiotensin system (RAS) caused by SARS-CoV-2 infection may increase the relative activity of angiotensin II compared with angiotensin (1-7) and may be an important contributor to COVID-19 pathophysiology. Objective: To evaluate the efficacy and safety of RAS modulation using 2 investigational RAS agents, TXA-127 (synthetic angiotensin [1-7]) and TRV-027 (an angiotensin II type 1 receptor-biased ligand), that are hypothesized to potentiate the action of angiotensin (1-7) and mitigate the action of the angiotensin II. Design, Setting, and Participants: Two randomized clinical trials including adults hospitalized with acute COVID-19 and new-onset hypoxemia were conducted at 35 sites in the US between July 22, 2021, and April 20, 2022; last follow-up visit: July 26, 2022. Interventions: A 0.5-mg/kg intravenous infusion of TXA-127 once daily for 5 days or placebo. A 12-mg/h continuous intravenous infusion of TRV-027 for 5 days or placebo. Main Outcomes and Measures: The primary outcome was oxygen-free days, an ordinal outcome that classifies a patient's status at day 28 based on mortality and duration of supplemental oxygen use; an adjusted odds ratio (OR) greater than 1.0 indicated superiority of the RAS agent vs placebo. A key secondary outcome was 28-day all-cause mortality. Safety outcomes included allergic reaction, new kidney replacement therapy, and hypotension. Results: Both trials met prespecified early stopping criteria for a low probability of efficacy. Of 343 patients in the TXA-127 trial (226 [65.9%] aged 31-64 years, 200 [58.3%] men, 225 [65.6%] White, and 274 [79.9%] not Hispanic), 170 received TXA-127 and 173 received placebo. Of 290 patients in the TRV-027 trial (199 [68.6%] aged 31-64 years, 168 [57.9%] men, 195 [67.2%] White, and 225 [77.6%] not Hispanic), 145 received TRV-027 and 145 received placebo. Compared with placebo, both TXA-127 (unadjusted mean difference, -2.3 [95% CrI, -4.8 to 0.2]; adjusted OR, 0.88 [95% CrI, 0.59 to 1.30]) and TRV-027 (unadjusted mean difference, -2.4 [95% CrI, -5.1 to 0.3]; adjusted OR, 0.74 [95% CrI, 0.48 to 1.13]) resulted in no difference in oxygen-free days. In the TXA-127 trial, 28-day all-cause mortality occurred in 22 of 163 patients (13.5%) in the TXA-127 group vs 22 of 166 patients (13.3%) in the placebo group (adjusted OR, 0.83 [95% CrI, 0.41 to 1.66]). In the TRV-027 trial, 28-day all-cause mortality occurred in 29 of 141 patients (20.6%) in the TRV-027 group vs 18 of 140 patients (12.9%) in the placebo group (adjusted OR, 1.52 [95% CrI, 0.75 to 3.08]). The frequency of the safety outcomes was similar with either TXA-127 or TRV-027 vs placebo. Conclusions and Relevance: In adults with severe COVID-19, RAS modulation (TXA-127 or TRV-027) did not improve oxygen-free days vs placebo. These results do not support the hypotheses that pharmacological interventions that selectively block the angiotensin II type 1 receptor or increase angiotensin (1-7) improve outcomes for patients with severe COVID-19. Trial Registration: ClinicalTrials.gov Identifier: NCT04924660.

Inflammation and Coagulation during Critical Illness and Long-Term Cognitive Impairment and Disability.

Rationale: The biological mechanisms of long-term cognitive impairment and disability after critical illness are unclear.Objectives: To test the hypothesis that markers of acute inflammation and coagulation are associated with subsequent long-term cognitive impairment and disability.Methods: We obtained plasma samples from adults with respiratory failure or shock on Study Days 1, 3, and 5 and measured concentrations of CRP (C-reactive protein), IFN-γ, IL-1ß, IL-6, IL-8, IL-10, IL-12, MMP-9 (matrix metalloproteinase-9), TNF-α (tumor necrosis factor-α), soluble TNF receptor 1, and protein C. At 3 and 12 months after discharge, we assessed global cognition, executive function, and activities of daily living. We analyzed associations between markers and outcomes using multivariable regression, adjusting for age, sex, education, comorbidities, baseline cognition, doses of sedatives and opioids, stroke risk (in cognitive models), and baseline disability scores (in disability models).Measurements and Main Results: We included 548 participants who were a median (interquartile range) of 62 (53-72) years old, 88% of whom were mechanically ventilated, and who had an enrollment Sequential Organ Failure Assessment score of 9 (7-11). After adjusting for covariates, no markers were associated with long-term cognitive function. Two markers, CRP and MMP-9, were associated with greater disability in basic and instrumental activities of daily living at 3 and 12 months. No other markers were consistently associated with disability outcomes.Conclusions: Markers of systemic inflammation and coagulation measured early during critical illness are not associated with long-term cognitive outcomes and demonstrate inconsistent associations with disability outcomes. Future studies that pair longitudinal measurement of inflammation and related pathways throughout the course of critical illness and during recovery with long-term outcomes are needed.

Protocolized Postextubation Respiratory Support to Prevent Reintubation: A Randomized Clinical Trial.

Rationale: Respiratory support (noninvasive ventilation or high-flow nasal cannula) applied at the time of extubation has been reported to reduce reintubation rates, but concerns regarding effectiveness have limited uptake into practice.Objectives: To determine if providing postextubation respiratory support to all patients undergoing extubation in a medical ICU would decrease the incidence of reintubation.Methods: We conducted a pragmatic, two-armed, cluster-crossover trial of adults undergoing extubation from invasive mechanical ventilation between October 1, 2017, and March 31, 2019, in the medical ICU of an academic medical center. Patients were assigned to either protocolized postextubation respiratory support (a respiratory therapist-driven protocol in which patients with suspected hypercapnia received noninvasive ventilation and patients without suspected hypercapnia received high-flow nasal cannula) or usual care (postextubation management at the discretion of treating clinicians). The primary outcome was reintubation within 96 hours of extubation.Measurements and Main Results: A total of 751 patients were enrolled. Of the 359 patients assigned to protocolized support, 331 (92.2%) received postextubation respiratory support compared with 66 of 392 patients (16.8%) assigned to usual care, a difference driven by differential use of high-flow nasal cannula (74.7% vs. 2.8%). A total of 57 patients (15.9%) in the protocolized support group experienced reintubation compared with 52 patients (13.3%) in the usual care group (odds ratio, 1.23; 95% confidence interval, 0.82 to 1.84; P = 0.32).Conclusions: Among a broad population of critically ill adults undergoing extubation from invasive mechanical ventilation at an academic medical center, protocolized postextubation respiratory support, primarily characterized by an increase in the use of high-flow nasal cannula, did not prevent reintubation compared with usual care.Clinical trial registered with www.clinicaltrials.gov (NCT0328831).

Balanced Crystalloids versus Saline in Critically Ill Adults.

BACKGROUND: Both balanced crystalloids and saline are used for intravenous fluid administration in critically ill adults, but it is not known which results in better clinical outcomes. METHODS: In a pragmatic, cluster-randomized, multiple-crossover trial conducted in five intensive care units at an academic center, we assigned 15,802 adults to receive saline (0.9% sodium chloride) or balanced crystalloids (lactated Ringer's solution or Plasma-Lyte A) according to the randomization of the unit to which they were admitted. The primary outcome was a major adverse kidney event within 30 days - a composite of death from any cause, new renal-replacement therapy, or persistent renal dysfunction (defined as an elevation of the creatinine level to ≥200% of baseline) - all censored at hospital discharge or 30 days, whichever occurred first. RESULTS: Among the 7942 patients in the balanced-crystalloids group, 1139 (14.3%) had a major adverse kidney event, as compared with 1211 of 7860 patients (15.4%) in the saline group (marginal odds ratio, 0.91; 95% confidence interval [CI], 0.84 to 0.99; conditional odds ratio, 0.90; 95% CI, 0.82 to 0.99; P=0.04). In-hospital mortality at 30 days was 10.3% in the balanced-crystalloids group and 11.1% in the saline group (P=0.06). The incidence of new renal-replacement therapy was 2.5% and 2.9%, respectively (P=0.08), and the incidence of persistent renal dysfunction was 6.4% and 6.6%, respectively (P=0.60). CONCLUSIONS: Among critically ill adults, the use of balanced crystalloids for intravenous fluid administration resulted in a lower rate of the composite outcome of death from any cause, new renal-replacement therapy, or persistent renal dysfunction than the use of saline. (Funded by the Vanderbilt Institute for Clinical and Translational Research and others; SMART-MED and SMART-SURG ClinicalTrials.gov numbers, NCT02444988 and NCT02547779 .).

Balanced Crystalloids versus Saline in Noncritically Ill Adults.

BACKGROUND: Comparative clinical effects of balanced crystalloids and saline are uncertain, particularly in noncritically ill patients cared for outside an intensive care unit (ICU). METHODS: We conducted a single-center, pragmatic, multiple-crossover trial comparing balanced crystalloids (lactated Ringer's solution or Plasma-Lyte A) with saline among adults who were treated with intravenous crystalloids in the emergency department and were subsequently hospitalized outside an ICU. The type of crystalloid that was administered in the emergency department was assigned to each patient on the basis of calendar month, with the entire emergency department crossing over between balanced crystalloids and saline monthly during the 16-month trial. The primary outcome was hospital-free days (days alive after discharge before day 28). Secondary outcomes included major adverse kidney events within 30 days - a composite of death from any cause, new renal-replacement therapy, or persistent renal dysfunction (defined as an elevation of the creatinine level to ≥200% of baseline) - all censored at hospital discharge or 30 days, whichever occurred first. RESULTS: A total of 13,347 patients were enrolled, with a median crystalloid volume administered in the emergency department of 1079 ml and 88.3% of the patients exclusively receiving the assigned crystalloid. The number of hospital-free days did not differ between the balanced-crystalloids and saline groups (median, 25 days in each group; adjusted odds ratio with balanced crystalloids, 0.98; 95% confidence interval [CI], 0.92 to 1.04; P=0.41). Balanced crystalloids resulted in a lower incidence of major adverse kidney events within 30 days than saline (4.7% vs. 5.6%; adjusted odds ratio, 0.82; 95% CI, 0.70 to 0.95; P=0.01). CONCLUSIONS: Among noncritically ill adults treated with intravenous fluids in the emergency department, there was no difference in hospital-free days between treatment with balanced crystalloids and treatment with saline. (Funded by the Vanderbilt Institute for Clinical and Translational Research and others; SALT-ED ClinicalTrials.gov number, NCT02614040 .).

Haloperidol and Ziprasidone for Treatment of Delirium in Critical Illness.

BACKGROUND: There are conflicting data on the effects of antipsychotic medications on delirium in patients in the intensive care unit (ICU). METHODS: In a randomized, double-blind, placebo-controlled trial, we assigned patients with acute respiratory failure or shock and hypoactive or hyperactive delirium to receive intravenous boluses of haloperidol (maximum dose, 20 mg daily), ziprasidone (maximum dose, 40 mg daily), or placebo. The volume and dose of a trial drug or placebo was halved or doubled at 12-hour intervals on the basis of the presence or absence of delirium, as detected with the use of the Confusion Assessment Method for the ICU, and of side effects of the intervention. The primary end point was the number of days alive without delirium or coma during the 14-day intervention period. Secondary end points included 30-day and 90-day survival, time to freedom from mechanical ventilation, and time to ICU and hospital discharge. Safety end points included extrapyramidal symptoms and excessive sedation. RESULTS: Written informed consent was obtained from 1183 patients or their authorized representatives. Delirium developed in 566 patients (48%), of whom 89% had hypoactive delirium and 11% had hyperactive delirium. Of the 566 patients, 184 were randomly assigned to receive placebo, 192 to receive haloperidol, and 190 to receive ziprasidone. The median duration of exposure to a trial drug or placebo was 4 days (interquartile range, 3 to 7). The median number of days alive without delirium or coma was 8.5 (95% confidence interval [CI], 5.6 to 9.9) in the placebo group, 7.9 (95% CI, 4.4 to 9.6) in the haloperidol group, and 8.7 (95% CI, 5.9 to 10.0) in the ziprasidone group (P=0.26 for overall effect across trial groups). The use of haloperidol or ziprasidone, as compared with placebo, had no significant effect on the primary end point (odds ratios, 0.88 [95% CI, 0.64 to 1.21] and 1.04 [95% CI, 0.73 to 1.48], respectively). There were no significant between-group differences with respect to the secondary end points or the frequency of extrapyramidal symptoms. CONCLUSIONS: The use of haloperidol or ziprasidone, as compared with placebo, in patients with acute respiratory failure or shock and hypoactive or hyperactive delirium in the ICU did not significantly alter the duration of delirium. (Funded by the National Institutes of Health and the VA Geriatric Research Education and Clinical Center; MIND-USA ClinicalTrials.gov number, NCT01211522 .).

Identifying Clinical Research Priorities in Adult Pulmonary and Critical Care. NHLBI Working Group Report.

Preventing, treating, and promoting recovery from critical illness due to pulmonary disease are foundational goals of the critical care community and the NHLBI. Decades of clinical research in acute respiratory distress syndrome, acute respiratory failure, pneumonia, and sepsis have yielded improvements in supportive care, which have translated into improved patient outcomes. Novel therapeutics have largely failed to translate from promising preclinical findings into improved patient outcomes in late-phase clinical trials. Recent advances in personalized medicine, "big data," causal inference using observational data, novel clinical trial designs, preclinical disease modeling, and understanding of recovery from acute illness promise to transform the methods of pulmonary and critical care clinical research. To assess the current state of, research priorities for, and future directions in adult pulmonary and critical care research, the NHLBI assembled a multidisciplinary working group of investigators. This working group identified recommendations for future research, including 1) focusing on understanding the clinical, physiological, and biological underpinnings of heterogeneity in syndromes, diseases, and treatment response with the goal of developing targeted, personalized interventions; 2) optimizing preclinical models by incorporating comorbidities, cointerventions, and organ support; 3) developing and applying novel clinical trial designs; and 4) advancing mechanistic understanding of injury and recovery to develop and test interventions targeted at achieving long-term improvements in the lives of patients and families. Specific areas of research are highlighted as especially promising for making advances in pneumonia, acute hypoxemic respiratory failure, and acute respiratory distress syndrome.

Effect of balanced crystalloids versus saline on urinary biomarkers of acute kidney injury in critically ill adults.

BACKGROUND: Recent trials have suggested use of balanced crystalloids may decrease the incidence of major adverse kidney events compared to saline in critically ill adults. The effect of crystalloid composition on biomarkers of early acute kidney injury remains unknown. METHODS: From February 15 to July 15, 2016, we conducted an ancillary study to the Isotonic Solutions and Major Adverse Renal Events Trial (SMART) comparing the effect of balanced crystalloids versus saline on urinary levels of neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) among 261 consecutively-enrolled critically ill adults admitted from the emergency department to the medical ICU. After informed consent, we collected urine 36 ± 12 h after hospital admission and measured NGAL and KIM-1 levels using commercially available ELISAs. Levels of NGAL and KIM-1 at 36 ± 12 h were compared between patients assigned to balanced crystalloids versus saline using a Mann-Whitney U test. RESULTS: The 131 patients (50.2%) assigned to the balanced crystalloid group and the 130 patients (49.8%) assigned to the saline group were similar at baseline. Urinary NGAL levels were significantly lower in the balanced crystalloid group (median, 39.4 ng/mg [IQR 9.9 to 133.2]) compared with the saline group (median, 64.4 ng/mg [IQR 27.6 to 339.9]) (P < 0.001). Urinary KIM-1 levels did not significantly differ between the balanced crystalloid group (median, 2.7 ng/mg [IQR 1.5 to 4.9]) and the saline group (median, 2.4 ng/mg [IQR 1.3 to 5.0]) (P = 0.36). CONCLUSIONS: In this ancillary analysis of a clinical trial comparing balanced crystalloids to saline among critically ill adults, balanced crystalloids were associated with lower urinary concentrations of NGAL and similar urinary concentrations of KIM-1, compared with saline. These results suggest only a modest reduction in early biomarkers of acute kidney injury with use of balanced crystalloids compared with saline. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT02444988 . Date registered: May 15, 2015.

Effect of Vitamin C, Thiamine, and Hydrocortisone on Ventilator- and Vasopressor-Free Days in Patients With Sepsis: The VICTAS Randomized Clinical Trial.

Importance: Sepsis is a common syndrome with substantial morbidity and mortality. A combination of vitamin C, thiamine, and corticosteroids has been proposed as a potential treatment for patients with sepsis. Objective: To determine whether a combination of vitamin C, thiamine, and hydrocortisone every 6 hours increases ventilator- and vasopressor-free days compared with placebo in patients with sepsis. Design, Setting, and Participants: Multicenter, randomized, double-blind, adaptive-sample-size, placebo-controlled trial conducted in adult patients with sepsis-induced respiratory and/or cardiovascular dysfunction. Participants were enrolled in the emergency departments or intensive care units at 43 hospitals in the United States between August 2018 and July 2019. After enrollment of 501 participants, funding was withheld, leading to an administrative termination of the trial. All study-related follow-up was completed by January 2020. Interventions: Participants were randomized to receive intravenous vitamin C (1.5 g), thiamine (100 mg), and hydrocortisone (50 mg) every 6 hours (n = 252) or matching placebo (n = 249) for 96 hours or until discharge from the intensive care unit or death. Participants could be treated with open-label corticosteroids by the clinical team, with study hydrocortisone or matching placebo withheld if the total daily dose was greater or equal to the equivalent of 200 mg of hydrocortisone. Main Outcomes and Measures: The primary outcome was the number of consecutive ventilator- and vasopressor-free days in the first 30 days following the day of randomization. The key secondary outcome was 30-day mortality. Results: Among 501 participants randomized (median age, 62 [interquartile range {IQR}, 50-70] years; 46% female; 30% Black; median Acute Physiology and Chronic Health Evaluation II score, 27 [IQR, 20.8-33.0]; median Sequential Organ Failure Assessment score, 9 [IQR, 7-12]), all completed the trial. Open-label corticosteroids were prescribed to 33% and 32% of the intervention and control groups, respectively. Ventilator- and vasopressor-free days were a median of 25 days (IQR, 0-29 days) in the intervention group and 26 days (IQR, 0-28 days) in the placebo group, with a median difference of -1 day (95% CI, -4 to 2 days; P = .85). Thirty-day mortality was 22% in the intervention group and 24% in the placebo group. Conclusions and Relevance: Among critically ill patients with sepsis, treatment with vitamin C, thiamine, and hydrocortisone, compared with placebo, did not significantly increase ventilator- and vasopressor-free days within 30 days. However, the trial was terminated early for administrative reasons and may have been underpowered to detect a clinically important difference. Trial Registration: ClinicalTrials.gov Identifier: NCT03509350.

Impact of a Follow-up Telephone Call Program on 30-Day Readmissions (FUTR-30): A Pragmatic Randomized Controlled Real-world Effectiveness Trial.

BACKGROUND: Telephone call programs are a common intervention used to improve patients' transition to outpatient care after hospital discharge. OBJECTIVE: To examine the impact of a follow-up telephone call program as a readmission reduction initiative. RESEARCH DESIGN: Pragmatic randomized controlled real-world effectiveness trial. SUBJECTS: We enrolled and randomized all patients discharged home from a hospital general medicine service to a follow-up telephone call program or usual care discharge. Patients discharged against medical advice were excluded. The intervention was a hospital program, delivering a semistructured follow-up telephone call from a nurse within 3-7 days of discharge, designed to assess understanding and provide education, and assistance to support discharge plan implementation. MEASURES: Our primary endpoint was hospital inpatient readmission within 30 days identified by the electronic health record. Secondary endpoints included observation readmission, emergency department revisit, and mortality within 30 days, and patient experience ratings. RESULTS: All 3054 patients discharged home were enrolled and randomized to the telephone call program (n=1534) or usual care discharge (n=1520). Using a prespecified intention-to-treat analysis, we found no evidence supporting differences in 30-day inpatient readmissions [14.9% vs. 15.3%; difference -0.4 (95% confidence interval, 95% CI), -2.9 to 2.1; P=0.76], observation readmissions [3.8% vs. 3.6%; difference 0.2 (95% CI, -1.1 to 1.6); P=0.74], emergency department revisits [6.1% vs. 5.4%; difference 0.7 (95% CI, -1.0 to 2.3); P=0.43], or mortality [4.4% vs. 4.9%; difference -0.5 (95% CI, -2.0 to 1.0); P=0.51] between telephone call and usual care groups. CONCLUSIONS: We found no evidence of an impact on 30-day readmissions or mortality due to the postdischarge telephone call program.

Acute kidney injury risk-based screening in pediatric inpatients: a pragmatic randomized trial.

BACKGROUND: Pediatric acute kidney injury (AKI) is common and associated with increased morbidity, mortality, and length of stay. We performed a pragmatic randomized trial testing the hypothesis that AKI risk alerts increase AKI screening. METHODS: All intensive care and ward admissions of children aged 28 days through 21 years without chronic kidney disease from 12/6/2016 to 11/1/2017 were included. The intervention alert displayed if calculated AKI risk was > 50% and no serum creatinine (SCr) was ordered within 24 h. The primary outcome was SCr testing within 48 h of AKI risk > 50%. RESULTS: Among intensive care admissions, 973/1909 (51%) were randomized to the intervention. Among those at risk, more SCr tests were ordered for the intervention group than for controls (418/606, 69% vs. 361/597, 60%, p = 0.002). AKI incidence and severity were the same in intervention and control groups. Among ward admissions, 5492/10997 (50%) were randomized to the intervention, and there were no differences between groups in SCr testing, AKI incidence, or severity of AKI. CONCLUSIONS: Alerts based on real-time prediction of AKI risk increased screening rates in intensive care but not pediatric ward settings. Pragmatic clinical trials provide the opportunity to assess clinical decision support and potentially eliminate ineffective alerts.

Balanced Crystalloids versus Saline in Sepsis. A Secondary Analysis of the SMART Clinical Trial.

Rationale: Administration of intravenous crystalloid solutions is a fundamental therapy for sepsis, but the effect of crystalloid composition on patient outcomes remains unknown.Objectives: To compare the effect of balanced crystalloids versus saline on 30-day in-hospital mortality among critically ill adults with sepsis.Methods: Secondary analysis of patients from SMART (Isotonic Solutions and Major Adverse Renal Events Trial) admitted to the medical ICU with an International Classification of Diseases, 10th Edition, Clinical Modification System code for sepsis, using multivariable regression to control for potential confounders.Measurements and Main Results: Of 15,802 patients enrolled in SMART, 1,641 patients were admitted to the medical ICU with a diagnosis of sepsis. A total of 217 patients (26.3%) in the balanced crystalloids group experienced 30-day in-hospital morality compared with 255 patients (31.2%) in the saline group (adjusted odds ratio [aOR], 0.74; 95% confidence interval [CI], 0.59-0.93; P = 0.01). Patients in the balanced group experienced a lower incidence of major adverse kidney events within 30 days (35.4% vs. 40.1%; aOR, 0.78; 95% CI, 0.63-0.97) and a greater number of vasopressor-free days (20 ± 12 vs. 19 ± 13; aOR, 1.25; 95% CI, 1.02-1.54) and renal replacement therapy-free days (20 ± 12 vs. 19 ± 13; aOR, 1.35; 95% CI, 1.08-1.69) compared with the saline group.Conclusions: Among patients with sepsis in a large randomized trial, use of balanced crystalloids was associated with a lower 30-day in-hospital mortality compared with use of saline.Clinical trial registered with www.clinicaltrials.gov (NCT02444988).

Identifying tweets of personal health experience through word embedding and LSTM neural network.

BACKGROUND: As Twitter has become an active data source for health surveillance research, it is important that efficient and effective methods are developed to identify tweets related to personal health experience. Conventional classification algorithms rely on features engineered by human domain experts, and engineering such features is a challenging task and requires much human intelligence. The resultant features may not be optimal for the classification problem, and can make it challenging for conventional classifiers to correctly predict personal experience tweets (PETs) due to the various ways to express and/or describe personal experience in tweets. In this study, we developed a method that combines word embedding and long short-term memory (LSTM) model without the need to engineer any specific features. Through word embedding, tweet texts were represented as dense vectors which in turn were fed to the LSTM neural network as sequences. RESULTS: Statistical analyses of the results of 10-fold cross-validations of our method and conventional methods indicate that there exist significant differences (p < 0.01) in performance measures of accuracy, precision, recall, F1-score, and ROC/AUC, demonstrating that our approach outperforms the conventional methods in identifying PETs. CONCLUSION: We presented an efficient and effective method of identifying health-related personal experience tweets by combining word embedding and an LSTM neural network. It is conceivable that our method can help accelerate and scale up analyzing textual data of social media for health surveillance purposes, because of no need for the laborious and costly process of engineering features.

Balanced Crystalloids versus Saline in the Intensive Care Unit. The SALT Randomized Trial.

RATIONALE: Saline is the intravenous fluid most commonly administered to critically ill adults, but it may be associated with acute kidney injury and death. Whether use of balanced crystalloids rather than saline affects patient outcomes remains unknown. OBJECTIVES: To pilot a cluster-randomized, multiple-crossover trial using software tools within the electronic health record to compare saline to balanced crystalloids. METHODS: This was a cluster-randomized, multiple-crossover trial among 974 adults admitted to a tertiary medical intensive care unit from February 3, 2015 to May 31, 2015. The intravenous crystalloid used in the unit alternated monthly between saline (0.9% sodium chloride) and balanced crystalloids (lactated Ringer's solution or Plasma-Lyte A). Enrollment, fluid delivery, and data collection were performed using software tools within the electronic health record. The primary outcome was the difference between study groups in the proportion of isotonic crystalloid administered that was saline. The secondary outcome was major adverse kidney events within 30 days (MAKE30), a composite of death, dialysis, or persistent renal dysfunction. MEASUREMENTS AND MAIN RESULTS: Patients assigned to saline (n = 454) and balanced crystalloids (n = 520) were similar at baseline and received similar volumes of crystalloid by 30 days (median [interquartile range]: 1,424 ml [500-3,377] vs. 1,617 ml [500-3,628]; P = 0.40). Saline made up a larger proportion of the isotonic crystalloid given in the saline group than in the balanced crystalloid group (91% vs. 21%; P < 0.001). MAKE30 did not differ between groups (24.7% vs. 24.6%; P = 0.98). CONCLUSIONS: An electronic health record-embedded, cluster-randomized, multiple-crossover trial comparing saline with balanced crystalloids can produce well-balanced study groups and separation in crystalloid receipt. Clinical trial registered with www.clinicaltrials.gov (NCT 02345486).

Frailty and Subsequent Disability and Mortality among Patients with Critical Illness.

RATIONALE: The prevalence of frailty (diminished physiologic reserve) and its effect on outcomes for those aged 18 years and older with critical illness is unclear. OBJECTIVES: We hypothesized greater frailty would be associated with subsequent mortality, disability, and cognitive impairment, regardless of age. METHODS: At enrollment, we measured frailty using the Clinical Frailty Scale (range, 1 [very fit] to 7 [severely frail]). At 3 and 12 months post-discharge, we assessed vital status, instrumental activities of daily living, basic activities of daily living, and cognition. We used multivariable regression to analyze associations between Clinical Frailty Scale scores and outcomes, adjusting for age, sex, education, comorbidities, baseline disability, baseline cognition, severity of illness, delirium, coma, sepsis, mechanical ventilation, and sedatives/opiates. MEASUREMENTS AND MAIN RESULTS: We enrolled 1,040 patients who were a median (interquartile range) of 62 (53-72) years old and who had a median Clinical Frailty Scale score of 3 (3-5). Half of those with clinical frailty (i.e., Clinical Frailty Scale score ≥5) were younger than 65 years old. Greater Clinical Frailty Scale scores were independently associated with greater mortality (P = 0.01 at 3 mo and P < 0.001 at 12 mo) and with greater odds of disability in instrumental activities of daily living (P = 0.04 at 3 mo and P = 0.002 at 12 mo). Clinical Frailty Scale scores were not associated with disability in basic activities of daily living or with cognition. CONCLUSIONS: Frailty is common in critically ill adults aged 18 years and older and is independently associated with increased mortality and greater disability. Future studies should explore routine screening for clinical frailty in critically ill patients of all ages. Interventions to reduce mortality and disability among patients with heightened vulnerability should be developed and tested. Clinical trial registered with www.clinicaltrials.gov (NCT 00392795 and NCT 00400062).