Tackling Brain and Muscle Dysfunction in Acute Respiratory Distress Syndrome Survivors: NHLBI Workshop Report.

Acute respiratory distress syndrome (ARDS) is associated with long-term impairments in brain and muscle function that significantly impact the quality of life of those who survive the acute illness. The mechanisms underlying these impairments are not yet well understood, and evidence-based interventions to minimize the burden on patients remain unproved. The NHLBI of the NIH assembled a workshop in April 2023 to review the state of the science regarding ARDS-associated brain and muscle dysfunction, to identify gaps in current knowledge, and to determine priorities for future investigation. The workshop included presentations by scientific leaders across the translational science spectrum and was open to the public as well as the scientific community. This report describes the themes discussed at the workshop as well as recommendations to advance the field toward the goal of improving the health and well-being of ARDS survivors.

Flow-Limited and Reverse-Triggered Ventilator Dyssynchrony Are Associated With Increased Tidal and Dynamic Transpulmonary Pressure.

OBJECTIVES: Ventilator dyssynchrony may be associated with increased delivered tidal volumes (V t s) and dynamic transpulmonary pressure (ΔP L,dyn ), surrogate markers of lung stress and strain, despite low V t ventilation. However, it is unknown which types of ventilator dyssynchrony are most likely to increase these metrics or if specific ventilation or sedation strategies can mitigate this potential. DESIGN: A prospective cohort analysis to delineate the association between ten types of breaths and delivered V t , ΔP L,dyn , and transpulmonary mechanical energy. SETTING: Patients admitted to the medical ICU. PATIENTS: Over 580,000 breaths from 35 patients with acute respiratory distress syndrome (ARDS) or ARDS risk factors. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients received continuous esophageal manometry. Ventilator dyssynchrony was identified using a machine learning algorithm. Mixed-effect models predicted V t , ΔP L,dyn , and transpulmonary mechanical energy for each type of ventilator dyssynchrony while controlling for repeated measures. Finally, we described how V t , positive end-expiratory pressure (PEEP), and sedation (Richmond Agitation-Sedation Scale) strategies modify ventilator dyssynchrony's association with these surrogate markers of lung stress and strain. Double-triggered breaths were associated with the most significant increase in V t , ΔP L,dyn , and transpulmonary mechanical energy. However, flow-limited, early reverse-triggered, and early ventilator-terminated breaths were also associated with significant increases in V t , ΔP L,dyn , and energy. The potential of a ventilator dyssynchrony type to increase V t , ΔP L,dyn , or energy clustered similarly. Increasing set V t may be associated with a disproportionate increase in high-volume and high-energy ventilation from double-triggered breaths, but PEEP and sedation do not clinically modify the interaction between ventilator dyssynchrony and surrogate markers of lung stress and strain. CONCLUSIONS: Double-triggered, flow-limited, early reverse-triggered, and early ventilator-terminated breaths are associated with increases in V t , ΔP L,dyn , and energy. As flow-limited breaths are more than twice as common as double-triggered breaths, further work is needed to determine the interaction of ventilator dyssynchrony frequency to cause clinically meaningful changes in patient outcomes.

Analgesia and Sedation Use During Noninvasive Ventilation for Acute Respiratory Failure.

OBJECTIVES: To describe U.S. practice regarding administration of sedation and analgesia to patients on noninvasive ventilation (NIV) for acute respiratory failure (ARF) and to determine the association of this practice with odds of intubation or death. DESIGN: A retrospective multicenter cohort study. SETTING: A total of 1017 hospitals contributed data between January 2010 and September 2020 to the Premier Healthcare Database, a nationally representative healthcare database in the United States. PATIENTS: Adult (≥ 18 yr) patients admitted to U.S. hospitals requiring NIV for ARF. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We identified 433,357 patients on NIV of whom (26.7% [95% CI] 26.3%-27.0%) received sedation or analgesia. A total of 50,589 patients (11.7%) received opioids only, 40,646 (9.4%) received benzodiazepines only, 20,146 (4.6%) received opioids and benzodiazepines, 1.573 (0.4%) received dexmedetomidine only, and 2,639 (0.6%) received dexmedetomidine in addition to opioid and/or benzodiazepine. Of 433,357 patients receiving NIV, 50,413 (11.6%; 95% CI, 11.5-11.7%) patients underwent invasive mechanical ventilation on hospital days 2-5 or died on hospital days 2-30. Intubation was used in 32,301 patients (7.4%; 95% CI, 7.3-7.6%). Further, death occurred in 24,140 (5.6%; 95% CI, 5.5-5.7%). In multivariable analysis adjusting for relevant covariates, receipt of any medication studied was associated with increased odds of intubation or death. In inverse probability weighting, receipt of any study medication was also associated with increased odds of intubation or death (average treatment effect odds ratio 1.38; 95% CI, 1.35-1.40). CONCLUSIONS: The use of sedation and analgesia during NIV is common. Medication exposure was associated with increased odds of intubation or death. Further investigation is needed to confirm this finding and determine whether any subpopulations are especially harmed by this practice.

Mobile Mindfulness Intervention for Psychological Distress Among Intensive Care Unit Survivors: A Randomized Clinical Trial.

Importance: Although psychological distress is common among survivors of critical illness, there are few tailored therapies. Objective: To determine the optimal method for delivering a mindfulness intervention via a mobile app for critical illness survivors. Design, Setting, and Participants: This randomized clinical trial used a 2 × 2 × 2 factorial design and was conducted at 3 sites among survivors of critical illness with elevated postdischarge symptoms of depression. The study was conducted between August 2019 and July 2023. Interventions: Participants were randomized to 1 of 8 different groups as determined by 3 two-level intervention component combinations: intervention introduction method (mobile app vs therapist call), mindfulness meditation dose (once daily vs twice daily), and management of increasing symptoms (mobile app vs therapist call). Main Outcomes and Measures: The primary outcome was the 9-item Patient Health Questionnaire (PHQ-9) depression scale score (range, 0-27) at 1 month. Secondary outcomes included anxiety (7-item Generalized Anxiety Disorder) and posttraumatic stress disorder (Posttraumatic Stress Scale) symptoms at 1 and 3 months, adherence, and feasibility. General linear models were used to compare main effects and interactions of the components among intervention groups. A formal decisional framework was used to determine an optimized intervention version. Results: A total of 247 participants (mean [SD] age, 50.2 [15.4] years; 104 [42.1%] women) were randomized. Twice-daily meditation compared with once-daily meditation was associated with a 1.2 (95% CI, 0.04-2.4)-unit lower mean estimated PHQ-9 score at 1 month and a 1.5 (95% CI, 0.1-2.8)-unit lower estimated mean score at 3 months. The other 2 intervention components had no main effects on the PHQ-9. Across-group adherence was high (217 participants [87.9%] using the intervention at trial conclusion) and retention was strong (191 [77.3%] and 182 [73.7%] at 1 and 3 months, respectively). Conclusions and Relevance: A mindfulness intervention for survivors of critical illness that included an app-based introduction, twice-daily guided meditation, and app-based management of increasing depression symptoms was optimal considering effects on psychological distress symptoms, adherence, and feasibility. Trial Registration: ClinicalTrials.gov Identifier: NCT04038567.

Identifying low-dimensional trajectories of mechanically-ventilated patient systems: Empirical phenotypes of joint patient+care processes to enhance temporal analysis in ARDS research.

Refined management of mechanically ventilation is an obvious target for improving patient outcomes, but is impeded by the nature of data for study and hypothesis generation. The connections between clinical outcomes and temporal development of iatrogenic injuries current lung-protective ventilator settings remain poorly understood. Analysis of lung-ventilator system (LVS) evolution at relevant timescales is frustrated by data volume and multiple sources of heterogeneity. This work motivates, presents, and validates a computational pipeline for resolving LVS systems into the joint evolution of data-conditioned model parameters and ventilator information. Applied to individuals, the workflow yields a concise low-dimensional representation of LVS behavior expressed in phenotypic breath waveforms suitable for analysis. The effectiveness of this approach is demonstrated through application to multi-day observational series of 35 patients. Individual patient analyses reveal multiple types of patient-oriented dynamics and breath behavior to expose the complexity of LVS evolution; less than 10% of phenotype changes related to ventilator settings changes. Dynamics are shown to including both stable and unstable phenotype transitions as well as both discrete and continuous changes unrelated to ventilator settings. At a cohort scale, 721 phenotypes constructed from individual data are condensed into a set of 16 groups that empirically organize around certain settings (positive end-expository pressure and ventilator mode) and structurally similar pressure-volume loop characterizations. Individual and cohort scale phenotypes, which may be refined by hypothesis-specific constructions, provide a common framework for ongoing temporal analysis and investigation of LVS dynamics.

Extraneous Load, Patient Census, and Patient Acuity Correlate With Cognitive Load During ICU Rounds.

BACKGROUND: Cognitive load theory asserts that learning and performance degrade when cognitive load exceeds working memory capacity. This is particularly relevant in the learning environment of ICU rounds, when multidisciplinary providers integrate complex decision-making and teaching in a noisy, high-stress environment prone to cognitive distractions. RESEARCH QUESTION: What features of ICU rounds correlate with high provider cognitive load? STUDY DESIGN AND METHODS: This was an observational, multisite study of multidisciplinary providers during ICU rounds. Investigators recorded rounding characteristics and hourly extraneous cognitive load events during rounds (defined as distractions, episodes of split-attention or repetition, and deviations from standard communication format). After rounds, investigators measured each provider's cognitive load using the provider task load (PTL), an instrument derived from the National Aeronautics and Space Administration Task Load Index survey that assesses perceived workload associated with complex tasks. Relationships between rounding characteristics, extraneous load, and PTL score were evaluated using mixed-effects modeling. RESULTS: A total of 76 providers were observed during 32 rounds from December 2020 to May 2021. The mean rounding census ± SD was 12.5 ± 2.9 patients. The mean rounding time ± SD was 2 h 17 min ± 49 min. The mean extraneous load ± SD was 20.5 ± 4.5 events per hour, or one event every 2 min 51 s. This included 8.6 ± 3.4 distractions, 8.2 ± 4.2 communication deviations, 1.9 ± 1.4 repetitions, and 1.8 ± 1.3 episodes of split-attention per hour. Controlling for covariates, the hourly extraneous load events, number of new patients, and number of higher acuity patients were each associated with increased PTL score (slope, 2.40; 95% CI, 0.76-4.04; slope, 5.23; 95% CI, 2.02-8.43; slope, 3.35; 95% CI, 1.34-5.35, respectively). INTERPRETATION: Increased extraneous load, new patients, and patient acuity were associated with higher cognitive load during ICU rounds. These results can help direct how the ICU rounding structure may be modified to reduce workload and optimize provider learning and performance.

Mobile App-Based Mindfulness Intervention for Addressing Psychological Distress Among Survivors of Hospitalization for COVID-19 Infection.

BACKGROUND: Psychological distress symptoms are present and persistent among many patients who survive a critical illness like COVID-19. RESEARCH QUESTION: Could a self-directed mobile app-delivered mindfulness intervention be feasibly and rapidly implemented within a clinical trials network to reduce distress symptoms? STUDY DESIGN AND METHODS: A randomized clinical trial was conducted between January 2021 and May 2022 at 29 US sites and included survivors of hospitalization due to COVID-19-related illness with elevated symptoms of depression at discharge. Participants were randomized to intervention or usual care control. The intervention consisted of four themed weeks of daily audio, video, and text content. All study procedures were virtual. The primary outcome was depression symptoms assessed with the Patient Health Questionnaire 9 at 3 months. Secondary outcomes included anxiety (Generalized Anxiety Disorder 7-item scale), quality of life (EQ-5D), and adherence. We used general linear models to estimate treatment arm differences in outcomes over time. RESULTS: Among 56 randomized participants (mean age ± SD, 51.0 ± 13.2 years; 38 female [67.9%]; 14 Black participants [25%]), 45 (intervention: n = 23 [79%]; control: n = 22 [81%]) were retained at 6 months. There was no difference in mean improvement between intervention and control participants at 3 months in Patient Health Questionnaire 9 (-0.5 vs 0.1), Generalized Anxiety Disorder 7-item scale (-0.3 vs 0.1), or EQ-5D (-0.03 vs 0.02) scores, respectively; 6-month results were similar. Only 15 participants (51.7%) initiated the intervention, whereas the mean number ± SD of the 56 prescribed intervention activities completed was 12.0 ± 15.2. Regulatory approvals delayed trial initiation by nearly a year. INTERPRETATION: Among survivors of COVID-19 hospitalization with elevated psychological distress symptoms, a self-directed mobile app-based mindfulness intervention had poor adherence. Future psychological distress interventions mobilized at broad scale should focus efforts on patient engagement and regulatory simplification to enhance success. TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT04581200; URL: www.clinicaltrials.gov.