Oxygen extraction-guided transfusion strategy in critically ill patients: study protocol for a randomised, open-labelled, controlled trial.

Introduction: In critically ill patients, individualised strategies for red blood cell transfusion (RBCT) are lacking. The objective of this study is to demonstrate the potential advantages of employing an individualised transfusion strategy compared with a restrictive approach, in unselected intensive care unit (ICU) patients.

Methods: This will be a randomised, multicentre, international trial.

Heterogeneous impact of Sighs on mortality in patients with acute hypoxemic respiratory failure: insights from the PROTECTION study.

Background: Sigh breaths may impact outcomes in acute hypoxemic respiratory failure (AHRF) during assisted mechanical ventilation. We investigated whether sigh breaths may impact mortality in predefined subgroups of patients enrolled in the PROTECTION multicenter clinical trial according to: 1.the physiological response in oxygenation to Sigh (responders versus non-responders) and 2.

Impact of positive end-expiratory pressure on renal resistive index in mechanical ventilated patients.

Purpose: Growing evidence shows the complex interaction between lung and kidney in critically ill patients. The renal resistive index (RRI) is a bedside measurement of the resistance of the renal blood flow and it is correlated with kidney injury. The positive end-expiratory pressure (PEEP) level could affect the resistance of renal blood flow, so we assumed that RRI could help to monitoring the changes in renal hemodynamics at different PEEP levels.

Intraoperative Ventilation/Perfusion Mismatch and Postoperative Pulmonary Complications after Major Noncardiac Surgery: A Prospective Cohort Study.

Background: Postoperative pulmonary complications can increase hospital length of stay, postoperative morbidity, and mortality. Although many factors can increase the risk of postoperative pulmonary complications, it is not known whether intraoperative ventilation/perfusion (V/Q) mismatch can be associated with an increased risk of postoperative pulmonary complications after major noncardiac surgery.

Methods: This study enrolled patients undergoing general anesthesia for noncardiac surgery and evaluated intraoperative V/Q distribution using the automatic lung parameter estimator technique.

Estimation of the transpulmonary pressure from the central venous pressure in mechanically ventilated patients.

Transpulmonary pressure (P) calculation requires esophageal pressure (P) as a surrogate of pleural pressure (Ppl), but its calibration is a cumbersome technique. Central venous pressure (CVP) swings may reflect tidal variations in Ppl and could be used instead of P, but the interpretation of CVP waveforms could be difficult due to superposition of heartbeat-induced pressure changes. Thus, we developed a digital filter able to remove the cardiac noise to obtain a filtered CVP (f-CVP).

Prone Positioning and Molecular Biomarkers in COVID and Non-COVID ARDS: A Narrative Review.

Prone positioning (PP) represents a therapeutic intervention with the proven capacity of ameliorating gas exchanges and ventilatory mechanics indicated in acute respiratory distress syndrome (ARDS). When PP is selectively applied to moderate-severe cases of ARDS, it sensitively affects clinical outcomes, including mortality. After the COVID-19 outbreak, clinical application of PP peaked worldwide and was applied in 60% of treated cases, according to large reports.

Into the Dark Serum Proteome: Personalized Features of IgG1 and IgA1 Repertoires in Severe COVID-19 Patients.

Serum proteomics has matured and is now able to monitor hundreds of proteins quantitatively in large cohorts of patients. However, the fine characteristics of some of the most dominant proteins in serum, the immunoglobulins, are in these studies often ignored, due to their vast, and highly personalized, diversity in sequences. Here, we focus exclusively on these personalized features in the serum proteome and distinctively chose to study individual samples from a low diversity population: elderly donors infected by severe acute respiratory syndrome corona virus 2 (SARS-CoV-2).

Incidence and Determinants of Acute Kidney Injury after Prone Positioning in Severe COVID-19 Acute Respiratory Distress Syndrome.

(1) Background: Acute kidney injury (AKI) is common among critically ill COVID-19 patients, but its temporal association with prone positioning (PP) is still unknown, and no data exist on the possibility of predicting PP-associated AKI from bedside clinical variables. (2) Methods: We analyzed data from 93 COVID-19-related ARDS patients who underwent invasive mechanical ventilation (IMV) and at least one PP cycle. We collected hemodynamic variables, respiratory mechanics, and circulating biomarkers before, during, and after the first PP cycle.

Frailty trajectories in ICU survivors: A comparison between the clinical frailty scale and the Tilburg frailty Indicator and association with 1 year mortality.

Purpose: To test the agreement of the Clinical Frailty Scale (CFS) and the Tilburg Frailty Indicator (TFI), their association with 3, 6 months and 1-year mortality and the trajectory of frailty in a mixed population of ICU survivors.

Material And Methods: This is a prospective, multicenter, longitudinal study on ICU survivors ≥18 years old with an ICU stay >72 h. For each patient, sociodemographic and clinical data were collected.

Inspiratory pressure waveform influences time to failure, respiratory muscle fatigue, and metabolism during resistive breathing.

Increased ventilatory work beyond working capacity of the respiratory muscles can induce fatigue, resulting in limited respiratory muscle endurance (T ). Previous resistive breathing investigations all applied square wave inspiratory pressure as fatigue-inducing pattern. Spontaneous breathing pressure pattern more closely approximate a triangle waveform.

Clinical risk factors for increased respiratory drive in intubated hypoxemic patients.

Background: There is very limited evidence identifying factors that increase respiratory drive in hypoxemic intubated patients. Most physiological determinants of respiratory drive cannot be directly assessed at the bedside (e.g.

Cellular and molecular features of COVID-19 associated ARDS: therapeutic relevance.

The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection can be asymptomatic or cause a disease (COVID-19) characterized by different levels of severity. The main cause of severe COVID-19 and death is represented by acute (or acute on chronic) respiratory failure and acute respiratory distress syndrome (ARDS), often requiring hospital admission and ventilator support.The molecular pathogenesis of COVID-19-related ARDS (by now termed c-ARDS) is still poorly understood.

Effect of expiratory flow limitation on ventilation/perfusion mismatch and perioperative lung function during pneumoperitoneum and Trendelenburg position.

Background: Laparoscopic surgery and Trendelenburg position may affect the respiratory function and alter the gas exchange. Further the reduction of the lung volumes may contribute to the development of expiratory flow limitation (EFL). The latter is associated with an increased risk of postoperative pulmonary complications.

Effect of the Pandemic Outbreak on ICU-Associated Infections and Antibiotic Prescription Trends in Non-COVID19 Acute Respiratory Failure Patients.

Background: The COVID-19 pandemic had a relevant impact on the organization of intensive care units (ICU) and may have reduced the overall compliance with healthcare-associated infections (HAIs) prevention programs. Invasively ventilated patients are at high risk of ICU-associated infection, but there is little evidence regarding the impact of the pandemic on their occurrence in non-COVID-19 patients. Moreover, little is known of antibiotic prescription trends in the ICU during the first wave of the pandemic.

Long-term dyspnea, regional ventilation distribution and peripheral lung function in COVID-19 survivors: a 1 year follow up study.

Background: Dyspnea is common after COVID-19 pneumonia and can be characterized by a defective CO diffusion (DLCO) despite normal pulmonary function tests (PFT). Nevertheless, DLCO impairment tends to normalize at 1 year, with no dyspnea regression. The altered regional distribution of ventilation and a dysfunction of the peripheral lung may characterize dyspnea at 1 year after COVID-19 pneumonia.

Heterogeneity of Ventilation/Perfusion Mismatch at Different Levels of PEEP and in Mechanical Phenotypes of COVID-19 ARDS.

Background: COVID-19-related ARDS is characterized by severe hypoxemia with initially preserved lung compliance and impaired ventilation/perfusion (V̇/Q̇) matching. PEEP can increase end-expiratory lung volume, but its effect on V̇/Q̇ mismatch in COVID-19-related ARDS is not clear.

Methods: We enrolled intubated and mechanically ventilated subjects with COVID-19 ARDS and used the automatic lung parameter estimator (ALPE) to measure V̇/Q̇.

Point-of-care ultrasound training for residents in anaesthesia and critical care: results of a national survey comparing residents and training program directors' perspectives.

Background: Point-of-care ultrasound (POCUS) has become an essential tool for anaesthesia and critical care physicians and dedicated training is mandatory. This survey describes the current state of Italian residency training programs through the comparison of residents' and directors' perspective.

Methods: Observational prospective cross-sectional study: 12-question national e-survey sent to Italian directors of anaesthesia and critical care residency programs (N = 40) and residents (N = 3000).

Mechanical ventilation and COPD: from pathophysiology to ventilatory management.

In the chronic obstructive pulmonary disease (COPD), lung and chest-wall morphological alterations determine important and peculiar approaches to mechanical ventilation. Lung emphysema and reduced elastic recoil increase expiratory time, thus worsening dynamic hyperinflation, while airways chronic inflammation rises resistances and can determine distal air-trapping. Muscle wasting and fast fibers prevalence can result in weakness and in an earlier onset of muscle fatigue, prolonging the weaning process.

The Underestimated Role of Platelets in Severe Infection a Narrative Review.

Beyond their role in hemostasis, platelets have emerged as key contributors in the immune response; accordingly, the occurrence of thrombocytopenia during sepsis/septic shock is a well-known risk factor of mortality and a marker of disease severity. Recently, some studies elucidated that the response of platelets to infections goes beyond a simple fall in platelets count; indeed, sepsis-induced thrombocytopenia can be associated with-or even anticipated by-several changes, including an altered morphological pattern, receptor expression and aggregation. Of note, alterations in platelet function and morphology can occur even with a normal platelet count and can modify, depending on the nature of the pathogen, the pattern of host response and the severity of the infection.

Transparent decision support for mechanical ventilation using visualization of clinical preferences.

Background: Systems aiding in selecting the correct settings for mechanical ventilation should visualize patient information at an appropriate level of complexity, so as to reduce information overload and to make reasoning behind advice transparent. Metaphor graphics have been applied to this effect, but these have largely been used to display diagnostic and physiologic information, rather than the clinical decision at hand. This paper describes how the conflicting goals of mechanical ventilation can be visualized and applied in making decisions.

Individualized positive end-expiratory pressure guided by end-expiratory lung volume in early acute respiratory distress syndrome: study protocol for the multicenter, randomized IPERPEEP trial.

Background: In acute respiratory distress syndrome (ARDS), response to positive end-expiratory pressure (PEEP) is variable according to different degrees of lung recruitability. The search for a tool to individualize PEEP based on patients' individual response is warranted. End-expiratory lung volume (EELV) assessment by nitrogen washing-washout aids bedside estimation of PEEP-induced alveolar recruitment and may therefore help titrate PEEP on patient's individual recruitability.

Clinical implications of microvascular CT scan signs in COVID-19 patients requiring invasive mechanical ventilation.

Purpose: COVID-19-related acute respiratory distress syndrome (ARDS) is characterized by the presence of signs of microvascular involvement at the CT scan, such as the vascular tree in bud (TIB) and the vascular enlargement pattern (VEP). Recent evidence suggests that TIB could be associated with an increased duration of invasive mechanical ventilation (IMV) and intensive care unit (ICU) stay. The primary objective of this study was to evaluate whether microvascular involvement signs could have a prognostic significance concerning liberation from IMV.

Circulating Skeletal Troponin During Weaning From Mechanical Ventilation and Their Association to Diaphragmatic Function: A Pilot Study.

Patients with acute respiratory failure (ARF) may need mechanical ventilation (MV), which can lead to diaphragmatic dysfunction and muscle wasting, thus making difficult the weaning from the ventilator. Currently, there are no biomarkers specific for respiratory muscle and their function can only be assessed trough ultrasound or other invasive methods. Previously, the fast and slow isoform of the skeletal troponin I (fsTnI and ssTnI, respectively) have shown to be specific markers of muscle damage in healthy volunteers.