Project description:ObjectivesAs coronavirus disease 2019 is a novel disease, treatment strategies continue to be debated. This provides the intensive care community with a unique opportunity as the population of coronavirus disease 2019 patients requiring invasive mechanical ventilation is relatively homogeneous compared with other ICU populations. We hypothesize that the novelty of coronavirus disease 2019 and the uncertainty over its similarity with noncoronavirus disease 2019 acute respiratory distress syndrome resulted in substantial practice variation between hospitals during the first and second waves of coronavirus disease 2019 patients.DesignMulticenter retrospective cohort study.SettingTwenty-five hospitals in the Netherlands from February 2020 to July 2020, and 14 hospitals from August 2020 to December 2020.PatientsOne thousand two hundred ninety-four critically ill intubated adult ICU patients with coronavirus disease 2019 were selected from the Dutch Data Warehouse. Patients intubated for less than 24 hours, transferred patients, and patients still admitted at the time of data extraction were excluded.Measurements and main resultsWe aimed to estimate between-ICU practice variation in selected ventilation parameters (positive end-expiratory pressure, Fio2, set respiratory rate, tidal volume, minute volume, and percentage of time spent in a prone position) on days 1, 2, 3, and 7 of intubation, adjusted for patient characteristics as well as severity of illness based on Pao2/Fio2 ratio, pH, ventilatory ratio, and dynamic respiratory system compliance during controlled ventilation. Using multilevel linear mixed-effects modeling, we found significant (p ≤ 0.001) variation between ICUs in all ventilation parameters on days 1, 2, 3, and 7 of intubation for both waves.ConclusionsThis is the first study to clearly demonstrate significant practice variation between ICUs related to mechanical ventilation parameters that are under direct control by intensivists. Their effect on clinical outcomes for both coronavirus disease 2019 and other critically ill mechanically ventilated patients could have widespread implications for the practice of intensive care medicine and should be investigated further by causal inference models and clinical trials.
Project description:ObjectivesThere is limited evidence on the impact of protocolized ventilator weaning in pediatric acute respiratory distress syndrome, despite utilization in clinical trials and clinical care. We aimed to determine whether protocolized ventilator weaning shortens mechanical ventilation duration and PICU length of stay in pediatric acute respiratory distress syndrome survivors.DesignSecondary analysis of a prospective pediatric acute respiratory distress syndrome (Berlin definition) cohort from July 2011 to June 2019 analyzed using interrupted time series analysis pre- and postimplementations of a ventilator-weaning pathway. We compared duration of invasive ventilation and PICU length of stay in survivors before and after implementation of a ventilator-weaning pathway. We excluded PICU nonsurvivors and subjects with greater than 100 ventilator days.SettingLarge academic tertiary-care PICU.PatientsChildren with acute respiratory distress syndrome who survived to PICU discharge with less than or equal to 100 days of invasive mechanical ventilation.InterventionsImplementation of a ventilator-weaning pathway on May 2016.Measurements and main resultsOf 723 children with acute respiratory distress syndrome, 132 subjects died and six subjects with ventilation greater than 100 days were excluded. Of the remaining 585 subjects, 375 subjects had acute respiratory distress syndrome prior to pathway intervention and 210 after. Patients in the preintervention epoch were younger, more likely to have infectious acute respiratory distress syndrome, and had increased use of alternative ventilator modes. Pathway adoption was rapid and sustained. Controlling for temporality, pathway implementation was associated with a decrease of a median 3.6 ventilator days (95% CI, -5.4 to -1.7; p < 0.001). There was no change in the reintubation rates. Results were robust to multiple sensitivity analyses adjusting for confounders.ConclusionsVentilator-weaning pathway implementation shortened invasive ventilation duration in pediatric acute respiratory distress syndrome survivors with no change in reintubation. The effect size of this intervention was comparable with those targeted in acute respiratory distress syndrome trials.
Project description:Prone position has been used in acute respiratory distress syndrome (ARDS) patients for more than 40 years in ICU. After having demonstrated its capability to significantly improve oxygenation in a large number of patients, sometimes dramatically, this procedure has been found to prevent ventilator-induced lung injury, the primary concern for the intensivists managing ARDS patients. Over the time, several trials have been done, which regularly improved and refined from each other. At the end, significant improvement in survival has been demonstrated in the most severe ARDS patients, at a threshold of 100-150 mmHg PaO2/FiO2 ratio. The effect of proning on survival cannot be predicted and seems unrelated with both severity of oxygenation impairment and oxygenation response to proning. The rate of complication is declining with the increase in centers expertise. The pressure sores are more frequent in prone and require a special attention. Prone position is a key component of lung protective mechanical ventilation and should be used as a first line therapy in association with low tidal volume and neuromuscular blocking agents in patients with severe ARDS.
Project description:Rationale: Serial measurements of genome-wide transcriptional changes in alveolar macrophages (AMs) in patients with acute respiratory distress syndrome (ARDS) could identify dynamic biologic processes that are associated with clinical outcomes. Objectives: To identify associations between AM transcriptional programs and the composite endpoint of ventilator-free days (VFDs) over the course of ARDS. Methods: We performed unbiased genome-wide transcriptional profiling of AMs purified from bronchoalveolar lavage fluid collected from patients with ARDS. Cells were obtained at baseline (Day 1), Day 4, and Day 8 after ARDS onset. We assessed pathway enrichment in subjects with VFDs > 0 (VFD-Extubated/Alive) versus VFDs = 0 (VFD-Intubated/Dead) at each time point. Measurements and Main Results: We found highly divergent AM transcriptional patterns at all time points between ARDS patients based on their VFD status (FDR < 0.05). “M1-like” and pro-inflammatory gene sets such as IL-6-JAK-STAT signaling were significantly enriched in AMs isolated on Day 1 in VFD-Extubated/Alive versus VFD-Intubated/Dead subjects. In contrast, many of these same gene sets were associated with the VFD-Intubated/Dead subjects on Day 8. In patients who had samples from each time point, we identified multiple AM gene clusters whose temporal expression patterns were associated with VFD status. The relationship between AM expression profiles and VFDs was distinct in subjects with Direct (pulmonary) versus Indirect (extrapulmonary) ARDS. Conclusion: Clinically meaningful outcomes over the course of ARDS are associated with highly distinct AM transcriptional programs. Our findings suggest that interventions targeting the alveolar immune response should be tested within strictly defined time periods.
Project description:Acute respiratory distress syndrome (ARDS) is a heterogeneous form of acute, diffuse lung injury that is characterized by dysregulated inflammation, increased alveolar-capillary interface permeability, and non-cardiogenic pulmonary edema. In the general population, the incidence and mortality associated with ARDS over the last two decades have steadily declined in parallel with optimized approaches to pneumonia and other underlying causes of ARDS as well as increased utilization of multimodal treatment strategies that include lung-protective ventilation. In the cancer settings, significant declines in the incidence and mortality of ARDS over the past two decades have also been reported, although these rates remain significantly higher than those in the general population. Epidemiologic studies identify infection, including disseminated fungal pneumonias, as a major underlying cause of ARDS in the cancer setting. More than half of cancer patients who develop ARDS will not survive to hospital discharge. Those who do survive often face a protracted and often incomplete recovery, resulting in significant long-term physical, psychological, and cognitive sequelae. The residual organ dysfunction and poor functional status after ARDS may delay or preclude subsequent cancer treatments. As such, close collaboration between the critical care physicians and oncology team is essential in identifying and reversing the underlying causes and optimizing treatments for cancer patients with ARDS. This chapter reviews the diagnosis and common causes of ARDS in cancer and gives an update on the general management principles for cancer patients with ARDS in the ICU.
Project description:Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) regulates numerous intracellular signaling pathways involved in inflammation and apoptosis. We hypothesized that genetic variation in MAP3K1 might be associated with outcomes in patients with acute respiratory distress syndrome (ARDS), and that these variants would alter MAP3K1-mediated changes in inflammation and transcriptional regulation. To test this hypothesis, we genotyped single-nucleotide polymorphisms covering linkage disequilibrium bins in MAP3K1 in 306 subjects with ARDS from the ARDSNet FACTT (Fluid and Catheter Treatment Trial) study, and tested for associations between MAP3K1 single-nucleotide polymorphisms and ventilator-free days (VFDs) and mortality. We then validated these associations in a separate cohort of 241 patients with ARDS from Harborview Medical Center (Seattle, WA). We found the variant allele of rs832582 (MAP3K1906Val) was significantly associated with decreased VFDs using multivariate linear regression (-6.1 d, false discovery rate?=?0.06) in the FACTT cohort. In the Harborview Medical Center cohort, subjects homozygous for MAP3K1906Val also had decreased VFDs (-15.1 d, false discovery rate?<?0.01), and increased 28-day mortality (all subjects homozygous for the rare allele died). In whole blood stimulated with various innate immune agonists ex vivo, MAP3K1906Val was associated with increased IL-1?, IL-6, IL-8, monocyte chemoattractant protein 1, and TNF-? production. Transcriptome analysis of whole blood stimulated with Toll-like receptor 4 agonist ex vivo demonstrated enrichment of inflammatory gene sets in subjects homozygous for MAP3K1906Val. Our findings show a robust association between the variant allele of rs832582 (MAP3K1906Val) and decreased VFDs in patients with ARDS and suggest that this variant may predispose individuals to a greater inflammatory response.
Project description:Acute respiratory distress syndrome (ARDS) is an acute respiratory illness characterised by bilateral chest radiographical opacities with severe hypoxaemia due to non-cardiogenic pulmonary oedema. The COVID-19 pandemic has caused an increase in ARDS and highlighted challenges associated with this syndrome, including its unacceptably high mortality and the lack of effective pharmacotherapy. In this Seminar, we summarise current knowledge regarding ARDS epidemiology and risk factors, differential diagnosis, and evidence-based clinical management of both mechanical ventilation and supportive care, and discuss areas of controversy and ongoing research. Although the Seminar focuses on ARDS due to any cause, we also consider commonalities and distinctions of COVID-19-associated ARDS compared with ARDS from other causes.
Project description:The acute respiratory distress syndrome (ARDS) is a common cause of respiratory failure in critically ill patients and is defined by the acute onset of noncardiogenic pulmonary oedema, hypoxaemia and the need for mechanical ventilation. ARDS occurs most often in the setting of pneumonia, sepsis, aspiration of gastric contents or severe trauma and is present in ~10% of all patients in intensive care units worldwide. Despite some improvements, mortality remains high at 30-40% in most studies. Pathological specimens from patients with ARDS frequently reveal diffuse alveolar damage, and laboratory studies have demonstrated both alveolar epithelial and lung endothelial injury, resulting in accumulation of protein-rich inflammatory oedematous fluid in the alveolar space. Diagnosis is based on consensus syndromic criteria, with modifications for under-resourced settings and in paediatric patients. Treatment focuses on lung-protective ventilation; no specific pharmacotherapies have been identified. Long-term outcomes of patients with ARDS are increasingly recognized as important research targets, as many patients survive ARDS only to have ongoing functional and/or psychological sequelae. Future directions include efforts to facilitate earlier recognition of ARDS, identifying responsive subsets of patients and ongoing efforts to understand fundamental mechanisms of lung injury to design specific treatments.
Project description:Acute respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19) pneumonia is the main cause of the pandemic's death toll. The assessment of ARDS and time on invasive mechanical ventilation (IMV) could enhance the characterization of outcomes and management of this condition. This is a city-wide retrospective study of hospitalized patients with COVID-19 pneumonia from 5 March 2020 to 30 June 2020. Patients with critical illness were compared with those with non-critical illness. We examined the severity of ARDS and other factors associated with (i) weaning patients off IMV and (ii) mortality in a city-wide study in Louisville, KY. Of 522 patients with COVID-19 pneumonia, 219 (41.9%) were critically ill. Among critically ill patients, the median age was 60 years; 53% were male, 55% were White and 32% were African American. Of all critically ill patients, 52% had ARDS, and 38% of these had severe ARDS. Of the 25% of patients who were weaned off IMV, those with severe ARDS were weaned within eleven days versus five days for those without severe ARDS, p = 0.023. The overall mortality for critically ill patients was 22% versus 1% for those not critically ill. Furthermore, the 14-day mortality was 31% for patients with severe ARDS and 12% for patients without severe ARDS, p = 0.019. Patients with severe ARDS versus non-severe ARDS needed twice as long to wean off IMV (eleven versus five days) and had double the 14-day mortality of patients without severe ARDS.