ARDS is an acute inflammatory pulmonary process triggered by severe pulmonary and systemic insults to the alveolar-capillary membrane. This causes increased vascular permeability and the development ...of interstitial and alveolar protein-rich edema, leading to acute hypoxemic respiratory failure. Supportive treatment includes the use of lung-protective ventilatory strategies that decrease the work of breathing, can improve oxygenation, and minimize ventilator-induced lung injury. Despite substantial advances in supportive measures, there are no specific pharmacologic treatments for ARDS, and the overall hospital mortality rate remains about 40% in most series. The pathophysiology of ARDS involves interactions among multiple mechanisms, including immune cell infiltration, cytokine storm, alveolar-capillary barrier disruption, cell apoptosis, and the development of fibrosis. Here we review some new developments in the molecular basis of lung injury, with a focus on possible novel pharmacologic interventions aimed at improving the outcomes of patients with ARDS. Our focus is on platelet-endothelial cell adhesion molecule-1, which contributes to the maintenance and restoration of vascular integrity following barrier disruption. We also highlight the wingless-related integration site signaling pathway, which appears to be a central mechanism for lung healing as well as for fibrotic development.
This article discusses recently published articles reporting the incidence and outcome of patients with the acute respiratory distress syndrome (ARDS). This is a difficult task since there is a ...marked variability regarding the methodology of the few, large epidemiological, and observational studies on ARDS.
The review will mainly focus on publications from the past 18 months. We have reviewed new epidemiological studies reporting population-based incidence of ARDS. Also, we have reviewed the data on survival reported in observational and randomized controlled trials, discussed how the current ARDS definition modifies the true incidence of ARDS, and briefly mentioned recent approaches that appear to improve ARDS outcome.
On the basis of current evidence, it seems that the incidence and overall hospital mortality of ARDS has not changed substantially in the last decade. Independent of the definition used for identification of ARDS patients, reported population-based incidence of ARDS is an order of magnitude lower in Europe than in the USA. Current hospital mortality of combined moderate and severe ARDS reported in observational studies is greater than 40%.
Abstract
Although the defining elements of “acute respiratory distress syndrome” (ARDS) have been known for over a century, the syndrome was first described in 1967. Since then, despite several ...revisions of its conceptual definition, it remains a matter of debate whether ARDS is a discrete nosological entity. After almost 60 years, it is appropriate to examine how critical care has modeled this fascinating syndrome and affected patient’s outcome. Given that the diagnostic criteria of ARDS (e.g., increased pulmonary vascular permeability and diffuse alveolar damage) are difficult to ascertain in clinical practice, we believe that a step forward would be to standardize the assessment of pulmonary and extrapulmonary involvement in ARDS to ensure that each patient can receive the most appropriate and effective treatment. The selection of treatments based on arbitrary ranges of PaO
2
/FiO
2
lacks sufficient sensitivity to individualize patient care.
Usually, arterial oxygenation in patients with the acute respiratory distress syndrome (ARDS) improves substantially by increasing the level of positive end-expiratory pressure (PEEP). Herein, we are ...proposing a novel variable PaO
/(FiO
xPEEP) or P/FP
for PEEP ≥ 5 to address Berlin's definition gap for ARDS severity by using machine learning (ML) approaches.
We examined P/FP
values delimiting the boundaries of mild, moderate, and severe ARDS. We applied ML to predict ARDS severity after onset over time by comparing current Berlin PaO
/FiO
criteria with P/FP
under three different scenarios. We extracted clinical data from the first 3 ICU days after ARDS onset (N = 2738, 1519, and 1341 patients, respectively) from MIMIC-III database according to Berlin criteria for severity. Then, we used the multicenter database eICU (2014-2015) and extracted data from the first 3 ICU days after ARDS onset (N = 5153, 2981, and 2326 patients, respectively). Disease progression in each database was tracked along those 3 ICU days to assess ARDS severity. Three robust ML classification techniques were implemented using Python 3.7 (LightGBM, RF, and XGBoost) for predicting ARDS severity over time.
P/FP
ratio outperformed PaO
/FiO
ratio in all ML models for predicting ARDS severity after onset over time (MIMIC-III: AUC 0.711-0.788 and CORR 0.376-0.566; eICU: AUC 0.734-0.873 and CORR 0.511-0.745).
The novel P/FP
ratio to assess ARDS severity after onset over time is markedly better than current PaO
/FiO
criteria. The use of P/FP
could help to manage ARDS patients with a more precise therapeutic regimen for each ARDS category of severity.
The study of rainfall trends is crucial for food security and water availability in Alagoas state, Northeast of Brazil. In this work, monthly, seasonal and annual rainfall trends have been studied ...(1960–2016) for homogeneous rainfall regions over the eastern part of the Northeast Brazil (ENEB) and later related to climate variability. Cluster analysis was applied to identify homogeneous rainfall regions while the Mann–Kendall (MK), modified Mann–Kendall (MMK) and Pettitt tests were used in the analysis and identification of trends on a spatial and temporal scale. To relate rainfall and climate variability modes, Spearman's correlation was used in each homogeneous region. The rainfall series provided evidence of a general decrease in rainfall in the rainy period and an increase in the dry period, mainly over the driest region. The break points of time series occurred mostly in periods of great variations in values of modes of climate variability, especially the Monthly Niño3.4 Index and the Southern Oscillation Index (SOI), both having a robust influence across the region. Moreover, the probable rainfall in the time series with trends was different in most months before and after the breakpoint. After the breakpoint, probable rainfall was lower, influenced by the breakpoint year (size of the series before and after the breakpoint), which mainly occurred in the 1980s and 1990s and presented a warm phase and a greater number of El Niño events. The MK and MMK trend tests showed the ability to detect trends, although there is no established standard on which test or version to use due to self‐correlated, nonhomogeneous series with nonrandom or nonindependent data. Rainfall is an important variable for water and food security and in the monitoring of natural disasters. The changes detected in this study can be used as reference information for public policies on water resources and future studies for Alagoas and similar regions.
Temporal trends in rainfall were reported as climate variability.
Purpose
While our understanding of the pathogenesis and management of acute respiratory distress syndrome (ARDS) has improved over the past decade, estimates of its incidence have been controversial. ...The goal of this study was to examine ARDS incidence and outcome under current lung protective ventilatory support practices before and after the diagnosis of ARDS.
Methods
This was a 1-year prospective, multicenter, observational study in 13 geographical areas of Spain (serving a population of 3.55 million at least 18 years of age) between November 2008 and October 2009. Subjects comprised all consecutive patients meeting American-European Consensus Criteria for ARDS. Data on ventilatory management, gas exchange, hemodynamics, and organ dysfunction were collected.
Results
A total of 255 mechanically ventilated patients fulfilled the ARDS definition, representing an incidence of 7.2/100,000 population/year. Pneumonia and sepsis were the most common causes of ARDS. At the time of meeting ARDS criteria, mean PaO
2
/FiO
2
was 114 ± 40 mmHg, mean tidal volume was 7.2 ± 1.1 ml/kg predicted body weight, mean plateau pressure was 26 ± 5 cmH
2
O, and mean positive end-expiratory pressure (PEEP) was 9.3 ± 2.4 cmH
2
O. Overall ARDS intensive care unit (ICU) and hospital mortality was 42.7% (95%CI 37.7–47.8) and 47.8% (95%CI 42.8–53.0), respectively.
Conclusions
This is the first study to prospectively estimate the ARDS incidence during the routine application of lung protective ventilation. Our findings support previous estimates in Europe and are an order of magnitude lower than those reported in the USA and Australia. Despite use of lung protective ventilation, overall ICU and hospital mortality of ARDS patients is still higher than 40%.
Perioperative hypothermia causes postoperative complications. Prewarming reduces body temperature decrease in long-term surgeries. We aimed to assess the effect of different time-periods of ...prewarming on perioperative temperature in short-term transurethral resection under general anesthesia. Randomized, double-blind, controlled trial in patients scheduled for bladder or prostatic transurethral resection under general anesthesia. Eligible patients were randomly assigned to receive no-prewarming or prewarming during 15, 30, or 45 min using a forced-air blanket in the pre-anesthesia period. Tympanic temperature was used prior to induction of anesthesia and esophageal temperature intraoperatively. Primary outcome was the difference in core temperature among groups from the induction of general anesthesia until the end of surgery. Repeated measures multivariate analysis of covariance modeled the temperature response at each observation time according to prewarming. We examined modeled contrasts between temperature variables in subjects according to prophylaxis. We enrolled 297 patients and randomly assigned 76 patients to control group, 74 patients to 15-min group, 73 patients to 30-min group, and 74 patients to the 45-min group. Temperature in the control group before induction was 36.5 ± 0.5 °C. After prewarming, core temperature was significantly higher in 15- and 30-min groups (36.8 ± 0.5 °C, p = 0.004; 36.7 ± 0.5 °C, p = 0.041, respectively). Body temperature at the end of surgery was significantly lower in the control group (35.8 ± 0.6 °C) than in the three prewarmed groups (36.3 ± 0.6 °C in 15-min, 36.3 ± 0.5 °C in 30-min, and 36.3 ± 0.6 °C in 45-min group) (p < 0.001). Prewarming prior to short-term transurethral resection under general anesthesia reduced the body temperature drop during the perioperative period. These time-periods of prewarming also reduced the rate of postoperative complications.Study Registration Registered at ClinicalTrials.gov (Identifier: NCT03630887).
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