Sedation-Related Electroencephalographic Patterns in Acute Hypoxemic Respiratory Failure.

Rationale: There is no universal objective measure of the effect of sedation on brain activity and how to differentiate it from sleep. In patients with early acute hypoxemic respiratory failure (AHRF) we used the Odds Ratio Product (ORP), an electroencephalography (EEG)-based metric used to quantify the sleep-wake continuum. Despite patients behaviorally appearing asleep, we observed and quantified novel EEG patterns previously unobserved during natural sleep, and hypothesized these unnatural EEG patterns (EEG Ups ) reflect the effect of sedation.

Assessing inspiratory drive and effort in critically ill patients at the bedside.

Unlabelled: Monitoring inspiratory drive and effort may aid proper selection and setting of respiratory support in patients with acute respiratory failure (ARF), whether they are intubated or not. Although diaphragmatic electrical activity (EAdi) and esophageal manometry can be considered the reference methods for assessing respiratory drive and inspiratory effort, respectively, various alternative techniques exist, each with distinct advantages and limitations. This narrative review provides a comprehensive overview of bedside methods to assess respiratory drive and effort, with a primary focus on patients with ARF.

Physiological Consequences of Breathing Effort According to the Mode of Ventilation During Acute Hypoxemic Respiratory Failure.

Rationale: Excessive stress (distending pressure), strain (volume deformation), and drop in inspiratory alveolar pressure are proposed mechanisms for patient self-inflicted lung injury.

Objectives: To dissect the influence of inspiratory effort, respiratory mechanics, and ventilation mode on lung stress, strain, and drop in inspiratory alveolar pressure; and explore their impact on oxygenation and lung compliance.

Methods: International cohort study analyzing respiratory recordings (esophageal pressure) of patients with acute hypoxemic respiratory failure.

Longitudinal Characterization of Patient-Ventilator Asynchronies in Acute Hypoxemic Respiratory Failure.

We sought to analyze the prevalence of patient-ventilator asynchronies in subjects with hypoxemic respiratory failure because of COVID-19 ARDS and their association with clinical outcomes. This was a two-center observational cohort study using prospectively collected real-world data. We included adult subjects with COVID-19 ARDS who required mechanical ventilation for more than 48 hours.

Monitoring and preserving diaphragmatic function in mechanical ventilation.

Purpose Of Review: This review summarizes the evidence on clinical outcomes related to diaphragm dysfunction, providing an overview on available monitoring tools and strategies for its prevention and treatment.

Recent Findings: Long-term adverse functional outcomes in intensive care survivors are well documented, especially in patients with prolonged mechanical ventilation. Because diaphragm weakness is highly prevalent and strongly associated with weaning failure, a link between diaphragm weakness and adverse functional outcomes is probable.

Monitoring patients with acute respiratory failure during non-invasive respiratory support to minimize harm and identify treatment failure.

Non-invasive respiratory support (NRS), including high flow nasal oxygen therapy, continuous positive airway pressure and non-invasive ventilation, is a cornerstone in the management of critically ill patients who develop acute respiratory failure (ARF). Overall, NRS reduces the work of breathing and relieves dyspnea in many patients with ARF, sometimes avoiding the need for intubation and invasive mechanical ventilation with variable efficacy across diverse clinical scenarios. Nonetheless, prolonged exposure to NRS in the presence of sustained high respiratory drive and effort can result in respiratory muscle fatigue, cardiovascular collapse, and impaired oxygen delivery to vital organs, leading to poor outcomes in patients who ultimately fail NRS and require intubation.

Ventilation distribution during spontaneous breathing trials predicts liberation from mechanical ventilation: the VISION study.

Background: Predicting complete liberation from mechanical ventilation (MV) is still challenging. Electrical impedance tomography (EIT) offers a non-invasive measure of regional ventilation distribution and could bring additional information.

Research Question: Whether the display of regional ventilation distribution during a Spontaneous Breathing Trial (SBT) could help at predicting early and successful liberation from MV.

Monitoring and modulating respiratory drive in mechanically ventilated patients.

Purpose Of Review: Respiratory drive is frequently deranged in the ICU, being associated with adverse clinical outcomes. Monitoring and modulating respiratory drive to prevent potentially injurious consequences merits attention. This review gives a general overview of the available monitoring tools and interventions to modulate drive.

Reverse triggering ? a novel or previously missed phenomenon?

Background: Reverse triggering (RT) was described in 2013 as a form of patient-ventilator asynchrony, where patient's respiratory effort follows mechanical insufflation. Diagnosis requires esophageal pressure (P) or diaphragmatic electrical activity (EA), but RT can also be diagnosed using standard ventilator waveforms.

Hypothesis: We wondered (1) how frequently RT would be present but undetected in the figures from literature, especially before 2013; (2) whether it would be more prevalent in the era of small tidal volumes after 2000.

Dyssynchronous diaphragm contractions impair diaphragm function in mechanically ventilated patients.

Background: Pre-clinical studies suggest that dyssynchronous diaphragm contractions during mechanical ventilation may cause acute diaphragm dysfunction. We aimed to describe the variability in diaphragm contractile loading conditions during mechanical ventilation and to establish whether dyssynchronous diaphragm contractions are associated with the development of impaired diaphragm dysfunction.

Methods: In patients receiving invasive mechanical ventilation for pneumonia, septic shock, acute respiratory distress syndrome, or acute brain injury, airway flow and pressure and diaphragm electrical activity (Edi) were recorded hourly around the clock for up to 7 days.

Flow starvation during square-flow assisted ventilation detected by supervised deep learning techniques.

Background: Flow starvation is a type of patient-ventilator asynchrony that occurs when gas delivery does not fully meet the patients' ventilatory demand due to an insufficient airflow and/or a high inspiratory effort, and it is usually identified by visual inspection of airway pressure waveform. Clinical diagnosis is cumbersome and prone to underdiagnosis, being an opportunity for artificial intelligence. Our objective is to develop a supervised artificial intelligence algorithm for identifying airway pressure deformation during square-flow assisted ventilation and patient-triggered breaths.

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

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). 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.

Failure of First Transition to Pressure Support Ventilation After Spontaneous Awakening Trials in Hypoxemic Respiratory Failure: Influence of COVID-19.

Objectives: To describe the rate of failure of the first transition to pressure support ventilation (PSV) after systematic spontaneous awakening trials (SATs) in patients with acute hypoxemic respiratory failure (AHRF) and to assess whether the failure is higher in COVID-19 compared with AHRF of other etiologies. To determine predictors and potential association of failure with outcomes.

Design: Retrospective cohort study.

The oesophageal balloon for respiratory monitoring in ventilated patients: updated clinical review and practical aspects.

There is a well-recognised importance for personalising mechanical ventilation settings to protect the lungs and the diaphragm for each individual patient. Measurement of oesophageal pressure ( ) as an estimate of pleural pressure allows assessment of partitioned respiratory mechanics and quantification of lung stress, which helps our understanding of the patient's respiratory physiology and could guide individualisation of ventilator settings. Oesophageal manometry also allows breathing effort quantification, which could contribute to improving settings during assisted ventilation and mechanical ventilation weaning.

Causes, Consequences, and Treatments of Sleep and Circadian Disruption in the ICU: An Official American Thoracic Society Research Statement.

Sleep and circadian disruption (SCD) is common and severe in the ICU. On the basis of rigorous evidence in non-ICU populations and emerging evidence in ICU populations, SCD is likely to have a profound negative impact on patient outcomes. Thus, it is urgent that we establish research priorities to advance understanding of ICU SCD.

Reverse Triggering during Controlled Ventilation: From Physiology to Clinical Management.

Reverse triggering dyssynchrony is a frequent phenomenon recently recognized in sedated critically ill patients under controlled ventilation. It occurs in at least 30-55% of these patients and often occurs in the transition from fully passive to assisted mechanical ventilation. During reverse triggering, patient inspiratory efforts start after the passive insufflation by mechanical breaths.

The physiological underpinnings of life-saving respiratory support.

Treatment of respiratory failure has improved dramatically since the polio epidemic in the 1950s with the use of invasive techniques for respiratory support: mechanical ventilation and extracorporeal respiratory support. However, respiratory support is only a supportive therapy, designed to "buy time" while the disease causing respiratory failure abates. It ensures viable gas exchange and prevents cardiorespiratory collapse in the context of excessive loads.