Treatment of COVID-19-associated ARDS with umbilical cord-derived mesenchymal stromal cells in the STROMA-CoV-2 multicenter randomized double-blind trial: long-term safety, respiratory function, and quality of life

BACKGROUND

The STROMA-CoV-2 study was a French phase 2b, multicenter, double-blind, randomized, placebo-controlled clinical trial that did not identify a significant efficacy of umbilical cord-derived mesenchymal stromal cells in patients with SARS-CoV-2-induced acute respiratory distress syndrome. Safety on day 28 was found to be good. The aim of our extended study was to assess the 6- and 12-month safety of UC-MSCs administration in the STROMA-CoV-2 cohort.

METHODS

A detailed multi-domain assessment was conducted at 6 and 12 months following hospital discharge focusing on adverse events, lung computed tomography-scan, pulmonary and muscular functional status, and quality of life in the STROMA-CoV-2 cohort including SARS-CoV-2-related early (< 96 h) mild-to-severe acute respiratory distress syndrome.

RESULTS

Between April 2020 and October 2020, 47 patients were enrolled, of whom 19 completed a 1-year follow-up. There were no significant differences in any endpoints or adverse effects between the UC-MSCs and placebo groups at the 6- and 12-month assessments. Ground-glass opacities persisted at 1 year in 5 patients (26.3%). Furthermore, diffusing capacity for carbon monoxide remained altered over 1 year, although no patient required oxygen or non-invasive ventilatory support. Quality of life revealed declines in mental, emotional and physical health throughout the follow-up period, and the six-minute walking distance remained slightly impaired at the 1-year patient assessment.

CONCLUSIONS

This study suggests a favorable safety profile for the use of intravenous UC-MSCs in the context of the first French wave of SARS-CoV-2-related moderate-to-severe acute respiratory distress syndrome, with no adverse effects observed at 1 year.

One-year survival of aneurysmal subarachnoid hemorrhage after airplane transatlantic transfer - a monocenter retrospective study

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is preferentially treated by prompt endovascular coiling, which is not available in Guadeloupe. Subsequently, patients are transferred to Paris, France mainland, by commercial airplane (6751 km flight) after being managed according to guidelines. This study describes the characteristics, management and outcomes related to these patients.

METHODS

Retrospective observational cohort study of 148 patients admitted in intensive care unit for a suspected aSAH and transferred by airplane over a 10-year period (2010-2019).

RESULTS

The median [interquartile range] age was 53 [45-64] years and 61% were female. On admission, Glasgow coma scale was 15 [13-15], World Federation of Neurological Surgeons (WFNS) grading scale was 1 [1-3] and Fisher scale was 4 [2-4]. External ventricular drainage and mechanical ventilation were performed prior to the flight respectively in 42% and 47% of patients. One-year mortality was 16% over the study period. By COX logistic regression analysis, acute hydrocephalus (hazard ratio [HR] 2.34, 95% confidence interval [CI] 0.98-5.58) prior to airplane transfer, WFNS grading scale on admission (HR 1.53, 95% CI 1.16-2.02) and age (OR 1.03, 95% 1.00-1.07) were associated with one-year mortality.

CONCLUSION

When necessary, transatlantic air transfer of patients with suspected aSAH after management according to local guidelines seems feasible and safe.

[Non-invasive ventilation in acute respiratory failure of oncology-hematology patients: What are its current benefits and limitations?]

Acute respiratory failure (ARF) is a leading cause, along with sepsis, of admission to the intensive care unit (ICU) of patients with active cancer. Presenting variable clinical severity, ARF in onco-hematological patients has differing etiologies, primarily represented by possibly opportunistic acute infectious pneumonia (de novo hypoxemic ARF), and decompensation in chronic cardiac or respiratory diseases (e.g., acute pulmonary edema or exacerbated chronic obstructive pulmonary disease). In these patients, orotracheal intubation is associated with a doubled risk of in-hospital mortality. Consequently, over the last three decades, numerous researchers have attempted to demonstrate and pinpoint the precise role of non-invasive ventilation (NIV) in the specific context of ARF in onco-hematological patients. While the benefits of NIV in the management of acute pulmonary edema or alveolar hypoventilation (hypercapnic ARF) are well-demonstrated, its positioning in de novo hypoxemic ARF is debatable, and has recently been called into question. In the early 2000s, based on randomized controlled trials, NIV was recommended as first-line treatment, one reason being that it allowed significantly reduced use of orotracheal intubation. In the latest randomized studies, however, the benefits of NIV in terms of survival orotracheal intubation have not been observed; as a result, it is no longer recommended in the management of de novo hypoxemic ARF in onco-haematological patients.

Association between arterial oxygen and mortality across critically ill patients with hematologic malignancies: results from an international collaborative network

PURPOSE

Patients with hematological malignancies are at high risk for life-threatening complications. To date, little attention has been paid to the impact of hyperoxemia and excess oxygen use on mortality. The aim of this study was to investigate the association between partial pressure of arterial oxygen (PaO2) and 28-day mortality in critically ill patients with hematologic malignancies.

METHODS

Data from three international cohorts (Europe, Canada, Oceania) of patients who received respiratory support (noninvasive ventilation, high-flow nasal cannula, invasive mechanical ventilation) were obtained. We used mixed-effect Cox models to investigate the association between day one PaO2 or excess oxygen use (inspired fraction of oxygen ≥ 0.6 with PaO2 > 100 mmHg) on day-28 mortality.

RESULTS

11,249 patients were included. On day one, 5716 patients (50.8%) had normoxemia (60 ≤ PaO2 ≤ 100 mmHg), 1454 (12.9%) hypoxemia (PaO2 < 60 mmHg), and 4079 patients (36.3%) hyperoxemia (PaO2 > 100 mmHg). Excess oxygen was used in 2201 patients (20%). Crude day-28 mortality rate was 40.6%. There was a significant association between PaO2 and day-28 mortality with a U-shaped relationship (p < 0.001). Higher PaO2 levels (> 100 mmHg) were associated with day-28 mortality with a dose-effect relationship. Subgroup analyses showed an association between hyperoxemia and mortality in patients admitted with neurological disorders; however, the opposite relationship was seen across those admitted with sepsis and neutropenia. Excess oxygen use was also associated with subsequent day-28 mortality (adjusted hazard ratio (aHR) [95% confidence interval (CI)]: 1.11[1.04-1.19]). This result persisted after propensity score analysis (matched HR associated with excess oxygen:1.31 [1.20-1.1.44]).

CONCLUSION

In critically-ill patients with hematological malignancies, exposure to hyperoxemia and excess oxygen use were associated with increased mortality, with variable magnitude across subgroups. This might be a modifiable factor to improve mortality.

Increasing sweep gas flow reduces respiratory drive and dyspnea in non-intubated veno-arterial ECMO patients - a pilot study

BACKGROUND.

Data on assessment and management of dyspnea in patients on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock are lacking. We hypothesized that increasing sweep gas flow through the VA-ECMO oxygenator may decrease dyspnea in non-intubated VA-ECMO patients exhibiting clinically significant dyspnea, with a parallel reduction in respiratory drive.

METHODS.

Non-intubated, spontaneously breathing, supine patients on VA-ECMO for cardiogenic shock who presented with a visual analog dyspnea scale (dyspnea-VAS) ≥ 40/100 mm were included. Sweep gas flow was increased up to +6 L/min by three steps of +2 L/min each. Dyspnea was assessed with dyspnea-VAS and Multidimensional Dyspnea Profile. The respiratory drive was assessed by the electromyographic activity of the alae nasi and parasternal muscles.

RESULTS.

We included 21 patients. On inclusion, median dyspnea-VAS was 50 ([interquartile range] 45-60) mm and sweep gas flow was 1.0 L/min (0.5-2.0). An increase in sweep gas flow significantly decreased dyspnea-VAS (50[45-60] at baseline vs 20[10-30] at 6L/min; p<0.001). The decrease in dyspnea was greater for the sensory component of dyspnea (-50%[43-75]) than for the affective and emotional components (-17%[0-25] and -12%[0-17], p<0.001). An increase in sweep gas flow significantly decreased electromyographic activity of the alae nasi and parasternal muscles (-23%[36-10] and -20[41-0], p<0.001). There was a significant correlation between the sweep gas flow and the dyspnea-VAS (r=-0.91 95%CI[-0.94, -0.87]), between the respiratory drive and the sensory component of dyspnea (r=0.29 95%CI[0.13, 0.44]), between the respiratory drive and the affective component of dyspnea (r=0.29 95%CI[0.02, 0.54]) and between the sweep gas flow and the alae nasi and parasternal (r=-0.31 95%CI[-0.44, -0.22] and r=-0.25 95%CI[-0.44, -0.16]).

CONCLUSION.

In critically ill patients with VA-ECMO, an increase in sweep gas flow through the oxygenation membrane decreases dyspnea, possibly mediated by a decrease in respiratory drive.

Clinical features and outcomes of patients with pancreatic cancer requiring unplanned medical ICU admission: A retrospective multicenter study

BACKGROUND

We sought to describe the reasons for intensive care unit (ICU) admission and outcomes of patients with pancreatic cancer requiring unplanned medical ICU admission.

PATIENTS AND METHODS

Retrospective cohort study in five ICUs from 2009 to 2020. All patients with pancreatic cancer admitted to the ICU were included. Patients having undergone recent surgery were excluded (< 4 weeks).

RESULTS

269 patients were included. Tumors were mainly adenocarcinoma (90%). Main reason for admission was sepsis/septic shock (32%) with a biliary tract infection in 44 (51%) patients. Second reason for admission was gastrointestinal bleeding (28%). ICU and 3-month mortality rates were 26% and 59% respectively. Performance status 3-4 (odds ratio OR 3.58), disease status (responsive/stable -ref-, newly diagnosed OR 3.25, progressive OR 5.99), mechanical ventilation (OR 8.03), vasopressors (OR 4.19), SAPS 2 (OR 1.69) and pH (OR 0.02) were independently associated with ICU mortality. Performance status 3-4 (Hazard ratio HR 1.96) and disease status (responsive/stable -ref-, newly diagnosed HR 2.67, progressive HR 4.14) were associated with 3-month mortality.

CONCLUSION

Reasons for ICU admissions of pancreatic cancer patients differ from those observed in other solid cancer. Short- and medium-term mortality are strongly influenced by performance status and disease status at ICU admission.

An Initial Investigation of Diaphragm Neurostimulation in Patients with Acute Respiratory Distress Syndrome

BACKGROUND

Lung protective ventilation aims at limiting lung stress and strain. By reducing the amount of pressure transmitted by the ventilator into the lungs, diaphragm neurostimulation offers a promising approach to minimize ventilator-induced lung injury. This study investigates the physiologic effects of diaphragm neurostimulation in acute respiratory distress syndrome (ARDS) patients. The hypothesis was that diaphragm neurostimulation would improve oxygenation, would limit the distending pressures of the lungs, and would improve cardiac output.

METHODS

Patients with moderate ARDS were included after 48 h of invasive mechanical ventilation and had a left subclavian catheter placed to deliver bilateral transvenous phrenic nerve stimulation. Two 60-min volume-controlled mechanical ventilation (control) sessions were interspersed by two 60-min diaphragm neurostimulation sessions delivered continually, in synchrony with the ventilator. Gas exchange, lung mechanics, chest electrical impedance tomography, and cardiac index were continuously monitored and compared across four sessions. The primary endpoint was the Pao2/fraction of inspired oxygen (Fio2) ratio at the end of each session, and the secondary endpoints were lung mechanics and hemodynamics.

RESULTS

Thirteen patients were enrolled but the catheter could not be inserted in one, leaving 12 patients for analysis. All sessions were conducted without interruption and well tolerated. The Pao2/Fio2 ratio did not change during the four sessions. Median (interquartile range) plateau pressure was 23 (20 to 31) cm H2O and 21 (17 to 25) cm H2O, driving pressure was 14 (12 to 18) cm H2O and 11 (10 to 13) cm H2O, and end-inspiratory transpulmonary pressure was 9 (5 to 11) cm H2O and 7 (4 to 11) cm H2O during mechanical ventilation alone and during mechanical ventilation + neurostimulation session, respectively. The dorsal/ventral ventilation surface ratio was 0.70 (0.54 to 0.91) when on mechanical ventilation and 1.20 (0.76 to 1.33) during the mechanical ventilation + neurostimulation session. The cardiac index was 2.7 (2.3 to 3.5) l · min-1 · m-2 on mechanical ventilation and 3.0 (2.4 to 3.9) l · min-1 · m-2 on mechanical ventilation + neurostimulation.

CONCLUSIONS

This proof-of-concept study showed the feasibility of short-term diaphragm neurostimulation in conjunction with mechanical ventilation in ARDS patients. Diaphragm neurostimulation was associated with positive effects on lung mechanics and on hemodynamics.

EDITOR’S PERSPECTIVE

High Airway Occlusion Pressure Is Associated with Dyspnea and Increased Mortality in Critically Ill Mechanically Ventilated Patients

RATIONALE

100 ms airway occlusion pressure (P0.1) reflects central respiratory drive. We aimed to assess factors associated with P0.1 and whether an abnormally low or high P0.1 value is associated with higher mortality and longer duration of mechanical ventilation (MV).

METHODS

Secondary analysis of a prospective cohort study conducted in 10 intensive care units in France to evaluate dyspnea in communicative MV patients. In patients intubated for more than 24 hours, P0.1 was measured with dyspnea as soon as patients could communicate and the following day.

RESULTS

260 patients were assessed after a median time of ventilation of 4 days. P0.1 was 1.9 (1 - 3.5) cmH2O on enrollment, 24% had a P0.1 >3.5 cmH2O, 37% had a P0.1 between 1.5 and 3.5 cmH2O, and 39% had a P0.1 <1.5 cmH2O. In multivariable linear regression, independent factors associated with P0.1 level were presence of dyspnea (p=0.037), respiratory rate (p<0.001), and PaO2 (p=0.008). 90-day mortality was 33% in patients with P0.1 >3.5 cmH2O vs. 19% in those with a P0.1 between 1.5 and 3.5 cmH2O and 17% in patients with P0.1 <1.5 cmH2O (p=0.046). After adjustment for the main risk factors, P0.1 was associated with 90-day mortality (per cmH2O of P0.1, Hazard ratio 1.19, 95% Confidence interval 1.04 - 1.37, p=0.011). P0.1 was also independently associated with a longer duration of MV (per cmH2O of P0.1, Hazard ratio 1.10, 95% Confidence interval 1.02-1.19, p=0.016).

CONCLUSIONS

In patients receiving invasive mechanical ventilation, abnormally high P0.1 values may suggest dyspnea and is associated with higher mortality and prolonged duration of MV.

Dyspnoea in acutely ill mechanically ventilated adult patients: an ERS/ESICM statement

This statement outlines a review of the literature and current practice concerning the prevalence, clinical significance, diagnosis and management of dyspnoea in critically ill, mechanically ventilated adult patients. It covers the definition, pathophysiology, epidemiology, short- and middle-term impact, detection and quantification, and prevention and treatment of dyspnoea. It represents a collaboration of the European Respiratory Society and the European Society of Intensive Care Medicine. Dyspnoea ranks among the most distressing experiences that human beings can endure. Approximately 40% of patients undergoing invasive mechanical ventilation in the intensive care unit (ICU) report dyspnoea, with an average intensity of 45 mm on a visual analogue scale from 0 to 100 mm. Although it shares many similarities with pain, dyspnoea can be far worse than pain in that it summons a primal fear response. As such, it merits universal and specific consideration. Dyspnoea must be identified, prevented and relieved in every patient. In the ICU, mechanically ventilated patients are at high risk of experiencing breathing difficulties because of their physiological status and, in some instances, because of mechanical ventilation itself. At the same time, mechanically ventilated patients have barriers to signalling their distress. Addressing this major clinical challenge mandates teaching and training, and involves ICU caregivers and patients. This is even more important because, as opposed to pain which has become a universal healthcare concern, very little attention has been paid to the identification and management of respiratory suffering in mechanically ventilated ICU patients.

Dyspnoea in acutely ill mechanically ventilated adult patients: an ERS/ESICM statement

This statement outlines a review of the literature and current practice concerning the prevalence, clinical significance, diagnosis and management of dyspnoea in critically ill, mechanically ventilated adult patients. It covers the definition, pathophysiology, epidemiology, short- and middle-term impact, detection and quantification, and prevention and treatment of dyspnoea. It represents a collaboration of the European Respiratory Society (ERS) and the European Society of Intensive Care Medicine (ESICM). Dyspnoea ranks among the most distressing experiences that human beings can endure. Approximately 40% of patients undergoing invasive mechanical ventilation in the intensive care unit (ICU) report dyspnoea, with an average intensity of 45 mm on a visual analogue scale from 0 to 100 mm. Although it shares many similarities with pain, dyspnoea can be far worse than pain in that it summons a primal fear response. As such, it merits universal and specific consideration. Dyspnoea must be identified, prevented and relieved in every patient. In the ICU, mechanically ventilated patients are at high risk of experiencing breathing difficulties because of their physiological status and, in some instances, because of mechanical ventilation itself. At the same time, mechanically ventilated patients have barriers to signalling their distress. Addressing this major clinical challenge mandates teaching and training, and involves ICU caregivers and patients. This is even more important because, as opposed to pain which has become a universal healthcare concern, very little attention has been paid to the identification and management of respiratory suffering in mechanically ventilated ICU patients.

Sensory interventions to relieve dyspnoea in critically ill mechanically ventilated patients

BACKGROUND

In critically ill patients receiving mechanical ventilation, dyspnoea is frequent, severe and associated with an increased risk of neuropsychological sequelae. We evaluated the efficacy of sensory interventions targeting the brain rather than the respiratory system to relieve dyspnoea in mechanically ventilated patients.

METHODS

Patients receiving mechanical ventilation for ≥48 h and reporting dyspnoea (unidimensional dyspnoea visual analogue scale (Dyspnoea-VAS)) first underwent increased pressure support and then, in random order, auditory stimulation (relaxing music versus pink noise) and air flux stimulation (facial versus lower limb). Treatment responses were assessed using Dyspnoea-VAS, the Multidimensional Dyspnea Profile and measures of the neural drive to breathe (airway occlusion pressure (P 0.1) and electromyography of inspiratory muscles).

RESULTS

We included 46 patients (tracheotomy or intubation n=37; noninvasive ventilation n=9). Increasing pressure support decreased Dyspnoea-VAS by median 40 mm (p<0.001). Exposure to music decreased Dyspnoea-VAS compared with exposure to pink noise by median 40 mm (p<0.001). Exposure to facial air flux decreased Dyspnoea-VAS compared with limb air flux by median 30 mm (p<0.001). Increasing pressure support, but not music exposure and facial air flux, reduced P 0.1 by median 3.3 cmH2O (p<0.001).

CONCLUSIONS

In mechanically ventilated patients, sensory interventions can modulate the processing of respiratory signals by the brain irrespective of the intensity of the neural drive to breathe. It should therefore be possible to alleviate dyspnoea without resorting to pharmacological interventions or having to infringe the constraints of mechanical ventilation lung protection strategies by increasing ventilatory support.

Multiplex Polymerase Chain Reaction Assay to Detect Nasopharyngeal Viruses in Immunocompromised Patients With Acute Respiratory Failure

BACKGROUND

In immunocompromised patients with acute respiratory failure (ARF), the clinical significance of respiratory virus detection in the nasopharynx remains uncertain.

RESEARCH QUESTION

Is viral detection in nasopharyngeal swabs associated with causes and outcomes of ARF in immunocompromised patients?

STUDY DESIGN AND METHODS

This preplanned post hoc analysis of a randomized controlled trial enrolled immunocompromised patients admitted to 32 ICUs for ARF between May 2016 and December 2017. Nasopharyngeal swabs sampled at inclusion were assessed for 23 respiratory pathogens using multiplex polymerase chain reaction (PCR) assay. Causes of ARF were established by managing physicians and were reviewed by three expert investigators masked to the multiplex PCR assay results. Associations between virus detection in nasopharyngeal swabs, causes of ARF, and composite outcome of day 28 mortality, invasive mechanical ventilation (IMV), or both were assessed.

RESULTS

Among the 510 sampled patients, the multiplex PCR assay results were positive in 103 patients (20.2%), and a virus was detected in 102 samples: rhinoviruses or enteroviruses in 35.5%, coronaviruses in 10.9%, and flu-like viruses (influenza virus, parainfluenza virus, respiratory syncytial virus, human metapneumovirus) in 52.7%. The cause of ARF varied significantly according to the results of the multiplex PCR assay, especially the proportion of viral pneumonia: 50.0% with flu-like viruses, 14.0% with other viruses, and 3.6% when no virus was detected (P < .001). No difference was found in the composite outcome of day 28 mortality, IMV, or both according to positive assay findings (54.9% vs 54.7%; P = .965). In a pre-established subgroup analysis, flu-like virus detection was associated with a higher rate of day 28 mortality, IMV, or both among recipients of allogeneic hematopoietic stem cell transplantation compared with those without detected virus.

INTERPRETATION

In immunocompromised patients with ARF, the results of nasopharyngeal multiplex PCR assays are not associated with IMV or mortality. A final diagnosis of viral pneumonia is retained in one-third of patients with positive assay results and in one-half of the patients with a flu-like virus.

Prognosis of critically ill immunocompromised patients with virus-detected acute respiratory failure

BACKGROUND

Acute respiratory failure (ARF) is the leading cause of ICU admission. Viruses are increasingly recognized as a cause of pneumonia in immunocompromised patients, but epidemiologic data are scarce. We used the Groupe de Recherche en Réanimation Respiratoire en Onco-Hématologie's database (2003-2017, 72 intensive care units) to describe the spectrum of critically ill immunocompromised patients with virus-detected ARF and to report their outcomes. Then, patients with virus-detected ARF were matched based on clinical characteristics and severity (1:3 ratio) with patients with ARF from other origins.

RESULTS

Of the 4038 immunocompromised patients in the whole cohort, 370 (9.2%) had a diagnosis of virus-detected ARF and were included in the study. Influenza was the most common virus (59%), followed by respiratory syncytial virus (14%), with significant seasonal variation. An associated bacterial infection was identified in 79 patients (21%) and an invasive pulmonary aspergillosis in 23 patients (6%). The crude in-hospital mortality rate was 37.8%. Factors associated with mortality were: neutropenia (OR = 1.74, 95% confidence interval, CI [1.05-2.89]), poor performance status (OR = 1.84, CI [1.12-3.03]), and the need for invasive mechanical ventilation on the day of admission (OR = 1.97, CI [1.14-3.40]). The type of virus was not associated with mortality. After matching, patients with virus-detected ARF had lower mortality (OR = 0.77, CI [0.60-0.98]) than patients with ARF from other causes. This result was mostly driven by influenza-like viruses, namely, respiratory syncytial virus, parainfluenza virus, and human metapneumovirus (OR = 0.54, CI [0.33-0.88]).

CONCLUSIONS

In immunocompromised patients with virus-detected ARF, mortality is high, whatever the species, mainly influenced by clinical severity and poor general status. However, compared to non-viral ARF, in-hospital mortality was lower, especially for patients with detected viruses other than influenza.

Diaphragm function in patients with Covid-19-related acute respiratory distress syndrome on venovenous extracorporeal membrane oxygenation

BACKGROUND

Venovenous extracorporeal membrane oxygenation (VV ECMO) is frequently associated with deep sedation and neuromuscular blockades, that may lead to diaphragm dysfunction. However, the prevalence, risk factors, and evolution of diaphragm dysfunction in patients with VV ECMO are unknown. We hypothesized that the prevalence of diaphragm dysfunction is high and that diaphragm activity influences diaphragm function changes.

METHODS

Patients with acute respiratory distress syndrome (ARDS) requiring VV ECMO were included in two centers. Diaphragm function was serially assessed by measuring the tracheal pressure in response to phrenic nerve stimulation (Ptr,stim) from ECMO initiation (Day 1) until ECMO weaning. Diaphragm activity was estimated from the percentage of spontaneous breathing ventilation and by measuring the diaphragm thickening fraction (TFdi) with ultrasound.

RESULTS

Sixty-three patients were included after a median of 4 days (3-6) of invasive mechanical ventilation. Diaphragm dysfunction, defined by Ptr, stim ≤ 11 cmH2O, was present in 39 patients (62%) on Day 1 of ECMO. Diaphragm function did not change over the study period and was not influenced by the percentage of spontaneous breathing ventilation or the TFdi during the 1 week. Among the 63 patients enrolled in the study, 24 (38%) were still alive at the end of the study period (60 days).

CONCLUSIONS

Sixty-two percent of patients undergoing ECMO for ARDS related to SARS CoV-2 infection had a diaphragm dysfunction on Day 1 of ECMO initiation. Diaphragm function remains stable over time and was not associated with the percentage of time with spontaneous breathing.

CLINICALTRIALS

gov Identifier NCT04613752 (date of registration February 15, 2021).

One-Year Outcomes in Patients With Acute Stroke Requiring Mechanical Ventilation

BACKGROUND

Long-term outcomes of patients with severe stroke remain poorly documented. We aimed to characterize one-year outcomes of patients with stroke requiring mechanical ventilation in the intensive care unit (ICU).

METHODS

We conducted a prospective multicenter cohort study in 33 ICUs in France (2017-2019) on patients with consecutive strokes requiring mechanical ventilation for at least 24 hours. Outcomes were collected via telephone interviews by an independent research assistant. The primary end point was poor functional outcome, defined by a modified Rankin Scale score of 4 to 6 at 1 year. Multivariable mixed models investigated variables associated with the primary end point. Secondary end points included quality of life, activities of daily living, and anxiety and depression in 1-year survivors.

RESULTS

Among the 364 patients included, 244 patients (66.5% [95% CI, 61.7%-71.3%]) had a poor functional outcome, including 190 deaths (52.2%). After adjustment for non-neurological organ failure, age ≥70 years (odds ratio [OR], 2.38 [95% CI, 1.26-4.49]), Charlson comorbidity index ≥2 (OR, 2.01 [95% CI, 1.16-3.49]), a score on the Glasgow Coma Scale <8 at ICU admission (OR, 3.43 [95% CI, 1.98-5.96]), stroke subtype (intracerebral hemorrhage: OR, 2.44 [95% CI, 1.29-4.63] versus ischemic stroke: OR, 2.06 [95% CI, 1.06-4.00] versus subarachnoid hemorrhage: reference) remained independently associated with poor functional outcome. In contrast, a time between stroke diagnosis and initiation of mechanical ventilation >1 day was protective (OR, 0.56 [95% CI, 0.33-0.94]). A sensitivity analysis conducted after exclusion of patients with early decisions of withholding/withdrawal of care yielded similar results. We observed persistent physical and psychological problems at 1 year in >50% of survivors.

CONCLUSIONS

In patients with severe stroke requiring mechanical ventilation, several ICU admission variables may inform caregivers, patients, and their families on post-ICU trajectories and functional outcomes. The burden of persistent sequelae at 1 year reinforces the need for a personalized, multi-disciplinary, prolonged follow-up of these patients after ICU discharge.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03335995.

ESICM guidelines on acute respiratory distress syndrome: definition, phenotyping and respiratory support strategies

The aim of these guidelines is to update the 2017 clinical practice guideline (CPG) of the European Society of Intensive Care Medicine (ESICM). The scope of this CPG is limited to adult patients and to non-pharmacological respiratory support strategies across different aspects of acute respiratory distress syndrome (ARDS), including ARDS due to coronavirus disease 2019 (COVID-19). These guidelines were formulated by an international panel of clinical experts, one methodologist and patients' representatives on behalf of the ESICM. The review was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement recommendations. We followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach to assess the certainty of evidence and grade recommendations and the quality of reporting of each study based on the EQUATOR (Enhancing the QUAlity and Transparency Of health Research) network guidelines. The CPG addressed 21 questions and formulates 21 recommendations on the following domains: (1) definition; (2) phenotyping, and respiratory support strategies including (3) high-flow nasal cannula oxygen (HFNO); (4) non-invasive ventilation (NIV); (5) tidal volume setting; (6) positive end-expiratory pressure (PEEP) and recruitment maneuvers (RM); (7) prone positioning; (8) neuromuscular blockade, and (9) extracorporeal life support (ECLS). In addition, the CPG includes expert opinion on clinical practice and identifies the areas of future research.

Interventions Relieving Dyspnea in Intubated Patients Show Responsiveness of the Mechanical Ventilation-Respiratory Distress Observation Scale

Rationale: Breathing difficulties are highly stressful. In critically ill patients, they are associated with an increased risk of posttraumatic manifestations. Dyspnea, the corresponding symptom, cannot be directly assessed in noncommunicative patients. This difficulty can be circumvented using observation scales such as the mechanical ventilation-respiratory distress observation scale (MV-RDOS). Objective: To investigate the performance and responsiveness of the MV-RDOS to infer dyspnea in noncommunicative intubated patients. Methods: Communicative and noncommunicative patients exhibiting breathing difficulties under mechanical ventilation were prospectively included and assessed using a dyspnea visual analog scale, MV-RDOS, EMG activity of alae nasi and parasternal intercostals, and EEG signatures of respiratory-related cortical activation (preinspiratory potentials). Inspiratory-muscle EMG and preinspiratory cortical activities are surrogates of dyspnea. Assessments were conducted at baseline, after adjustment of ventilator settings, and, in some cases, after morphine administration. Measurements and Main Results: Fifty patients (age, 67 [(interquartile interval [IQR]), 61-76] yr; Simplified Acute Physiology Score II, 52 [IQR, 35-62]) were included, 25 of whom were noncommunicative. Relief occurred in 25 (50%) patients after ventilator adjustments and in 21 additional patients after morphine administration. In noncommunicative patients, MV-RDOS score decreased from 5.5 (IQR, 4.2-6.6) at baseline to 4.2 (IQR, 2.1-4.7; P < 0.001) after ventilator adjustments and 2.5 (IQR, 2.1-4.2; P = 0.024) after morphine administration. MV-RDOS and alae nasi/parasternal EMG activities were positively correlated (ρ = 0.41 and 0.37, respectively). MV-RDOS scores were higher in patients with EEG preinspiratory potentials (4.9 [IQR, 4.2-6.3] vs. 4.0 [IQR, 2.1-4.9]; P = 0.002). Conclusions: The MV-RDOS seems able to detect and monitor respiratory symptoms reasonably well in noncommunicative intubated patients. Clinical trial registered with www.clinicaltrials.gov (NCT02801838).

Simulation study for evaluating an adaptive-randomisation Bayesian hybrid trial design with enrichment

Background

As we enter the era of precision medicine, the role of adaptive designs, such as response-adaptive randomisation or enrichment designs in drug discovery and development, has become increasingly important to identify the treatment given to a patient based on one or more biomarkers. Tailoring the ventilation supply technique according to the responsiveness of patients to positive end-expiratory pressure is a suitable setting for such a design.

Methods

In the setting of marker-strategy design, we propose a Bayesian response-adaptive randomisation with enrichment design based on group sequential analyses. This design combines the elements of enrichment design and response-adaptive randomisation. Concerning the enrichment strategy, Bayesian treatment-by-subset interaction measures were used to adaptively enrich the patients most likely to benefit from an experimental treatment while controlling the false-positive rate.The operating characteristics of the design were assessed by simulation and compared to those of alternate designs.

Results

The results obtained allowed the detection of the superiority of one treatment over another and the presence of a treatment-by-subgroup interaction while keeping the false-positive rate at approximately 5\% and reducing the average number of included patients. In addition, simulation studies identified that the number of interim analyses and the burn-in period may have an impact on the performance of the scheme.

Conclusion

The proposed design highlights important objectives of precision medicine, such as determining whether the experimental treatment is superior to another and identifying wheter such an efficacy could depend on patient profile.

Association between combination antibiotic therapy as opposed as monotherapy and outcomes of ICU patients with Pseudomonas aeruginosa ventilator-associated pneumonia: an ancillary study of the iDIAPASON trial

BACKGROUND

The optimal treatment duration and the nature of regimen of antibiotics (monotherapy or combination therapy) for Pseudomonas aeruginosa ventilator‑associated pneumonia (PA-VAP) remain debated. The aim of this study was to evaluate whether a combination antibiotic therapy is superior to a monotherapy in patients with PA-VAP in terms of reduction in recurrence and death, based on the 186 patients included in the iDIAPASON trial, a multicenter, randomized controlled trial comparing 8 versus 15 days of antibiotic therapy for PA-VAP.

METHODS

Patients with PA-VAP randomized in the iDIAPASON trial (short-duration-8 days vs. long-duration-15 days) and who received appropriate antibiotic therapy were eligible in the present study. The main objective is to compare mortality at day 90 according to the antibiotic therapy received by the patient: monotherapy versus combination therapy. The primary outcome was the mortality rate at day 90. The primary outcome was compared between groups using a Chi-square test. Time from appropriate antibiotic therapy to death in ICU or to censure at day 90 was represented using Kaplan-Meier survival curves and compared between groups using a Log-rank test.

RESULTS

A total of 169 patients were included in the analysis. The median duration of appropriate antibiotic therapy was 14 days. At day 90, among 37 patients (21.9%) who died, 17 received monotherapy and 20 received a combination therapy (P = 0.180). Monotherapy and combination antibiotic therapy were similar for the recurrence rate of VAP, the number of extra pulmonary infections, or the acquisition of multidrug-resistant (MDR) bacteria during the ICU stay. Patients in combination therapy were exposed to mechanical ventilation for 28 ± 12 days, as compared with 23 ± 11 days for those receiving monotherapy (P = 0.0243). Results remain similar after adjustment for randomization arm of iDIAPASON trial and SOFA score at ICU admission.

CONCLUSIONS

Except longer durations of antibiotic therapy and mechanical ventilation, potentially related to increased difficulty in achieving clinical cure, the patients in the combination therapy group had similar outcomes to those in the monotherapy group.

TRIAL REGISTRATION

NCT02634411 , Registered 15 December 2015.

Differences in clinical characteristics and outcomes between COVID-19 and influenza in critically ill adult patients: a national database study

OBJECTIVE

Prior to the coronavirus disease 2019 (COVID-19) pandemic, influenza was the most frequent cause of viral respiratory pneumonia requiring intensive care unit (ICU) admission. Few studies have compared the characteristics and outcomes of critically ill patients with COVID-19 and influenza.

METHODS

This was a French nationwide study comparing COVID-19 (March 1, 2020-June 30, 2021) and influenza patients (January 1, 2014-December 31, 2019) admitted to an ICU during pre-vaccination era. Primary outcome was in-hospital death. Secondary outcome was need for mechanical ventilation.

RESULTS

105,979 COVID-19 patients were compared to 18,763 influenza patients. Critically ill patients with COVID-19 were more likely to be men with more comorbidities. Patients with influenza required more invasive mechanical ventilation (47 vs. 34%, p<0·001), vasopressors (40% vs. 27, p<0·001) and renal-replacement therapy (22 vs. 7%, p<0·001). Hospital mortality was 25 and 21% (p<0·001) in patients with COVID-19 and influenza, respectively. In the subgroup of patients receiving invasive mechanical ventilation, ICU length of stay was significantly longer in patients with COVID-19 (18 [10-32] vs. 15 [8-26] days, p<0·001). Adjusting for age, gender, comorbidities, and modified SAPS II score, in-hospital death was higher in COVID-19 patients (adjusted sub-distribution hazard ratio [aSHR]=1.69; 95%CI=1.63-1.75) compared with influenza patients. COVID-19 was also associated with less invasive mechanical ventilation (aSHR=0.87; 95%CI=0.85-0.89) and a higher likelihood of death without invasive mechanical ventilation (aSHR=2.40; 95%CI=2.24-2.57).

CONCLUSION

Despite younger age and lower SAPS II score, critically ill COVID-19 patients had a longer hospital stay and higher mortality than patients with influenza.

Diaphragm Neurostimulation Assisted Ventilation in Critically Ill Patients

Diaphragm neurostimulation consists of placing electrodes directly on or in proximity to the phrenic nerve(s) to elicit diaphragmatic contractions. Since its initial description in the 18th century, indications have shifted from cardiopulmonary resuscitation to long-term ventilatory support. Recently, the technical development of devices for temporary diaphragm neurostimulation has opened up the possibility of a new era for the management of mechanically ventilated patients. Combining positive pressure ventilation with diaphragm neurostimulation offers a potentially promising new approach to the delivery of mechanical ventilation which may benefit multiple organ systems. Maintaining diaphragm contractions during ventilation may attenuate diaphragm atrophy and accelerate weaning from mechanical ventilation. Preventing atelectasis and preserving lung volume can reduce lung stress and strain and improve homogeneity of ventilation, potentially mitigating ventilator-induced lung injury. Furthermore, restoring the thoracoabdominal pressure gradient generated by diaphragm contractions may attenuate the drop in cardiac output induced by positive pressure ventilation. Experimental evidence suggests diaphragm neurostimulation may prevent neuroinflammation associated with mechanical ventilation. This review describes the historical development and evolving approaches to diaphragm neurostimulation during mechanical ventilation and surveys the potential mechanisms of benefit. The review proposes a research agenda and offers perspectives for the future of diaphragm neurostimulation assisted mechanical ventilation for critically ill patients.

Factors related to mortality in critically ill histoplasmosis: a multicenter retrospective study in Guadeloupe and French Guyana

PURPOSE

To describe clinical and biological features and the outcomes of patients admitted for histoplasmosis in two intensive care units (ICU) in French Guyana and in the French West Indies (Guadeloupe).

METHODS

All patients admitted to these two ICUs for culture-proven histoplasmosis between January 2014 to August 2022 were included in the study. Using univariate and multivariate analysis, we assessed risk factors at ICU admission that were associated with death.

RESULTS

Forty patients were included (65% men). Median age was 56 years and simplified acute physiologic score (SAPS) II was 65. HIV was found in 58%, another immunodeficiency was identified in 28%, and no underlying immunodeficiency could be identified in 14% of patients. Within the first 24 h of ICU admission, 85% of patients had acute respiratory failure, 78% had shock, 30% had coma, and 48% had hemophagocytic lymphohistiocytosis. Mechanical ventilation was instituted in 78% of patients and renal replacement therapy in 55%. The 30-day mortality was 53%. By multivariate analysis, factors independently associated with 30-day mortality were SOFA score (odds ratio [OR] 1.5, 95% confidence interval [CI] [1.1-2.1]), time between symptom onset and treatment per day (OR 1.1, 95% CI 1.0-1.1), and hemophagocytic lymphohistiocytosis (OR 6.4, 95% CI 1.1-47.5).

CONCLUSION

Histoplasmosis requiring ICU admission is a protean disease with multiple and severe organ involvement. Immunodeficiency is found in most patients. The prognosis remains severe despite appropriate treatment and is worsened by late treatment initiation.

Study protocol for a randomized controlled trial of Proportional Assist Ventilation for Minimizing the Duration of Mechanical Ventilation: the PROMIZING study

BACKGROUND

Proportional assist ventilation with load-adjustable gain factors (PAV+) is a mechanical ventilation mode that delivers assistance to breathe in proportion to the patient's effort. The proportional assistance, called the gain, can be adjusted by the clinician to maintain the patient's respiratory effort or workload within a normal range. Short-term and physiological benefits of this mode compared to pressure support ventilation (PSV) include better patient-ventilator synchrony and a more physiological response to changes in ventilatory demand.

METHODS

The objective of this multi-centre randomized controlled trial (RCT) is to determine if, for patients with acute respiratory failure, ventilation with PAV+ will result in a shorter time to successful extubation than with PSV. This multi-centre open-label clinical trial plans to involve approximately 20 sites in several continents. Once eligibility is determined, patients must tolerate a short-term PSV trial and either (1) not meet general weaning criteria or (2) fail a 2-min Zero Continuous Positive Airway Pressure (CPAP) Trial using the rapid shallow breathing index, or (3) fail a spontaneous breathing trial (SBT), in this sequence. Then, participants in this study will be randomized to either PSV or PAV+ in a 1:1 ratio. PAV+ will be set according to a target of muscular pressure. The weaning process will be identical in the two arms. Time to liberation will be the primary outcome; ventilator-free days and other outcomes will be measured.

DISCUSSION

Meta-analyses comparing PAV+ to PSV suggest PAV+ may benefit patients and decrease healthcare costs but no powered study to date has targeted the difficult to wean patient population most likely to benefit from the intervention, or used consistent timing for the implementation of PAV+. Our enrolment strategy, primary outcome measure, and liberation approaches may be useful for studying mechanical ventilation and weaning and can offer important results for patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02447692 . Prospectively registered on May 19, 2015.

Impact of corticosteroids on the duration of ventilatory support during severe acute exacerbations of chronic obstructive pulmonary disease in patients in the intensive care unit: a study protocol for a multicentre, randomized, placebo-controlled, double-blind trial

BACKGROUND

Patients who are admitted to the intensive care unit (ICU) for severe acute exacerbations of chronic obstructive pulmonary disease (COPD) have poor outcomes. Although international clinical practice guidelines cautiously recommend the routine use of systemic corticosteroids for COPD exacerbations, data are scarce and inconclusive regarding their benefit for most severe patients who require mechanical ventilation in the ICU. Furthermore, corticosteroids may be associated with an increased risk of infection, ICU-acquired limb weakness, and metabolic disorders.

METHODS AND ANALYSIS

This study is an investigator-initiated, multicentre, randomized, placebo-controlled, double-blind trial comparing systemic corticosteroids to placebo during severe acute exacerbations of COPD in patients who require mechanical ventilation in French ICUs. A total of 440 patients will be randomized 1:1 to methylprednisolone (1 mg/kg) or placebo for 5 days, and stratified according to initial mechanical ventilation (non-invasive or invasive), pneumonia as triggering factor, and recent use of systemic corticosteroids (< 48 h). The primary outcome is the number of ventilator-free days at day 28, defined as the number of days alive and without mechanical invasive and/or non-invasive ventilation between randomization and day 28. Secondary outcomes include non-invasive ventilation (NIV) failure rate, duration of mechanical ventilation (invasive and/or NIV), circulatory support (vasopressor), outcomes related to corticosteroid adverse events (severe hyperglycaemia, gastrointestinal bleeding, uncontrolled arterial hypertension, ICU-acquired weakness, ICU-acquired infections, and delirium), lengths of ICU and hospital stay, ICU and hospital mortality, day 28 and day 90 mortality, number of new exacerbation(s)/hospitalization(s) between hospital discharge and day 90, and dyspnoea and comfort at randomization, ICU discharge, and day 90. Subgroup analyses for the primary outcome are planned according to stratification criteria at randomization.

Decreased breathing variability is associated with poorer outcome in mechanically ventilated patients

Rationale: Breathing is a cyclic activity that is by nature variable. Breathing variability is modified in mechanically ventilated (MV) patients.

Objectives: We aimed to evaluate whether decreased variability on the day of transition from assist-control ventilation to a partial mode of assistance was associated with a poorer outcome.

Methods: This was an ancillary study of a multicenter, randomized, controlled trial comparing neurally adjusted ventilatory assist to pressure support ventilation. Flow and the electrical activity of the diaphragm (EAdi) were recorded within 48 h of switching from controlled ventilation to a partial mode of ventilatory assistance.

Measurements: Variability of flow and EAdi-related variables were quantified by the coefficient of variation, the amplitude ratio of the spectrum's first harmonic to its zero-frequency component (H1/DC) and two surrogates of complexity,.

Main Results: Ninety-eight patients ventilated for a median duration of 5 days were included. H1/DC of inspiratory flow and EAdi were lower in survivors than in non-survivors, suggesting a higher breathing variability in this population (for flow, 37%versus45%, p=0.041; for EAdi, 42%versus52%, p=0.002). By multivariate analysis, H1/DC of inspiratory EAdi was independently associated with day-28 mortality (odds ratio 1.10, p=0.002). H1/DC of inspiratory EAdi was lower in patients with a duration of MV<8 days (41%versus45%, p=0.022). Noise limit and the largest Lyapunov exponent suggested a lower complexity in patients with a duration of MV<8 days.

Conclusion: Higher breathing variability and lower complexity are associated with higher survival and lower duration of MV.

Abatacept/Ruxolitinib and Screening for Concomitant Respiratory Muscle Failure to Mitigate Fatality of Immune-Checkpoint Inhibitor Myocarditis

Immune-checkpoint-inhibitor (ICI)-associated myotoxicity involves the heart (myocarditis) and skeletal muscles (myositis), which frequently occur concurrently and is highly fatal. We report the results of a strategy that included identification of individuals with severe ICI-myocarditis by also screening for and managing concomitant respiratory muscle involvement with mechanical ventilation, as well as treatment with CTLA4-fusion protein abatacept and the Janus-kinase inhibitor ruxolitinib. Forty cases with definite ICI-myocarditis were included with pathological confirmation of concomitant myositis in the majority of patients. In the first 10 patients, using recommended guidelines, myotoxicity-related fatality occurred in 60%, consistent with historical controls. In the subsequent 30 cases, we instituted systematic screening for respiratory muscle involvement coupled with active ventilation and treatment using ruxolitinib and abatacept. Abatacept dose was adjusted using CD86-receptor occupancy on circulating monocytes. Myotoxicity-related fatality rate was 3.4%(1/30) in these 30 patients vs.60% in 1st quartile(p<0.0001). These clinical results are hypothesis-generating and need further evaluation.

One-Year Mental and Physical Health Assessment in Survivors after Extracorporeal Membrane Oxygenation for COVID-19-related Acute Respiratory Distress Syndrome

Rationale: Long-term outcomes of patients with coronavirus disease (COVID-19)-related acute respiratory distress syndrome treated with extracorporeal membrane oxygenation (ECMO) are unknown. Objectives: To assess physical examination, pulmonary function tests, anxiety, depression, post-traumatic stress disorder and quality of life at 6 and 12 months after ECMO onset. Methods: Multicenter, prospective study in patients who received ECMO for COVID-19 acute respiratory distress syndrome from March to June 2020 and survived hospital discharge. Measurements and Main Results: Of 80 eligible patients, 62 were enrolled in seven French ICUs. ECMO and invasive mechanical ventilation duration were 18 (11-25) and 36 (27-62) days, respectively. All were alive, but only 19/50 (38%) returned to work and 13/42 (31%) had recovered a normal sex drive at 1 year. Pulmonary function tests were almost normal at 6 months, except for Dl_CO, which was still impaired at 12 months. Mental health, role-emotional, and role-physical were the most impaired domain compared with patients receiving ECMO who did not have COVID-19. One year after ICU admission, 19/43 (44%) patients had significant anxiety, 18/43 (42%) had depression symptoms, and 21/50 (42%) were at risk for post-traumatic stress disorders. Conclusions: Despite the partial recovery of the lung function tests at 1 year, the physical and psychological function of this population remains impaired. Based on the comparison with long-term follow-up of patients receiving ECMO who did not have COVID-19, poor mental and physical health may be more related to COVID-19 than to ECMO in itself, although this needs confirmation.

Trends in clinical characteristics and outcomes of all critically ill COVID-19 adult patients hospitalized in France between March 2020 and June 2021: a national database study

INTRODUCTION

Studies regarding coronavirus disease 2019 (COVID-19) were mainly performed in the initial wave, but some small-scale data points to prognostic differences for patients in successive waves. We therefore aimed to study the impact of time on prognosis of ICU-admitted COVID-19 patients.

METHOD

We performed a national retrospective cohort study, including all adult patients hospitalized in French ICUs from March 1, 2020 to June 30, 2021, and identified three surge periods. Primary and secondary outcomes were in-hospital mortality and need for invasive mechanical ventilation, respectively.

RESULTS

105,979 critically ill ICU-admitted COVID-19 patients were allocated to the relevant three surge periods. In-hospital mortality for surges 1, 2, and 3 was, respectively, 24%, 27%, and 24%. Invasive mechanical ventilation was the highest level of respiratory support for 42%, 32%, and 31% (p < 0.001) over the whole period, with a decline in the use of vasopressors over time. Adjusted for age, sex, comorbidities, and modified Simplified Acute Physiology Score II at ICU admission, time period was associated with less invasive mechanical ventilation and a high risk of in-hospital death. Vaccination against COVID-19 was associated with a lower likelihood of invasive mechanical ventilation (adjusted sub-hazard ratio [aSHR] = 0.64 [0.53-0.76]) and intra-hospital death (aSHR = 0.80, [0.68-0.95]).

CONCLUSION

In this large database of ICU patients admitted for COVID-19, we observed a decline in invasive mechanical ventilation, vasopressors, and RRT use over time but a high risk of in-hospital death. Vaccination was identified as protective against the risk of invasive mechanical ventilation and in-hospital death.

Pleural and transpulmonary pressures to tailor protective ventilation in children

This review aims to: (1) describe the rationale of pleural (P_PL) and transpulmonary (P_L) pressure measurements in children during mechanical ventilation (MV); (2) discuss its usefulness and limitations as a guide for protective MV; (3) propose future directions for paediatric research. We conducted a scoping review on P_L in critically ill children using PubMed and Embase search engines. We included peer-reviewed studies using oesophageal (P_ES) and P_L measurements in the paediatric intensive care unit (PICU) published until September 2021, and excluded studies in neonates and patients treated with non-invasive ventilation. P_L corresponds to the difference between airway pressure and P_PL Oesophageal manometry allows measurement of P_ES, a good surrogate of P_PL, to estimate P_L directly at the bedside. Lung stress is the P_L, while strain corresponds to the lung deformation induced by the changing volume during insufflation. Lung stress and strain are the main determinants of MV-related injuries with P_L and P_PL being key components. P_L-targeted therapies allow tailoring of MV: (1) Positive end-expiratory pressure (PEEP) titration based on end-expiratory P_L (direct measurement) may be used to avoid lung collapse in the lung surrounding the oesophagus. The clinical benefit of such strategy has not been demonstrated yet. This approach should consider the degree of recruitable lung, and may be limited to patients in which PEEP is set to achieve an end-expiratory P_L value close to zero; (2) Protective ventilation based on end-inspiratory P_L (derived from the ratio of lung and respiratory system elastances), might be used to limit overdistention and volutrauma by targeting lung stress values < 20-25 cmH₂O; (3) P_PL may be set to target a physiological respiratory effort in order to avoid both self-induced lung injury and ventilator-induced diaphragm dysfunction; (4) P_PL or P_L measurements may contribute to a better understanding of cardiopulmonary interactions. The growing cardiorespiratory system makes children theoretically more susceptible to atelectrauma, myotrauma and right ventricle failure. In children with acute respiratory distress, P_PL and P_L measurements may help to characterise how changes in PEEP affect P_PL and potentially haemodynamics. In the PICU, P_PL measurement to estimate respiratory effort is useful during weaning and ventilator liberation. Finally, the use of P_PL tracings may improve the detection of patient ventilator asynchronies, which are frequent in children. Despite these numerous theoritcal benefits in children, P_ES measurement is rarely performed in routine paediatric practice. While the lack of robust clincal data partially explains this observation, important limitations of the existing methods to estimate P_PL in children, such as their invasiveness and technical limitations, associated with the lack of reference values for lung and chest wall elastances may also play a role. P_PL and P_L monitoring have numerous potential clinical applications in the PICU to tailor protective MV, but its usefulness is counterbalanced by technical limitations. Paediatric evidence seems currently too weak to consider oesophageal manometry as a routine respiratory monitoring. The development and validation of a noninvasive estimation of P_L and multimodal respiratory monitoring may be worth to be evaluated in the future.

High-Flow Versus VenturiMask Oxygen Therapy to Prevent Reintubation in Hypoxemic Patients after Extubation: A Multicenter Randomized Clinical Trial

Rationale: When compared with VenturiMask after extubation, high-flow nasal oxygen provides physiological advantages. Objectives: To establish whether high-flow oxygen prevents endotracheal reintubation in hypoxemic patients after extubation, compared with VenturiMask. Methods: In this multicenter randomized trial, 494 patients exhibiting Pa_O2:Fi_O2 ratio ⩽ 300 mm Hg after extubation were randomly assigned to receive high-flow or VenturiMask oxygen, with the possibility to apply rescue noninvasive ventilation before reintubation. High-flow use in the VenturiMask group was not permitted. Measurements and Main Results: The primary outcome was the rate of reintubation within 72 hours according to predefined criteria, which were validated a posteriori by an independent adjudication committee. Main secondary outcomes included reintubation rate at 28 days and the need for rescue noninvasive ventilation according to predefined criteria. After intubation criteria validation (n = 492 patients), 32 patients (13%) in the high-flow group and 27 patients (11%) in the VenturiMask group required reintubation at 72 hours (unadjusted odds ratio, 1.26 [95% confidence interval (CI), 0.70-2.26]; P = 0.49). At 28 days, the rate of reintubation was 21% in the high-flow group and 23% in the VenturiMask group (adjusted hazard ratio, 0.89 [95% CI, 0.60-1.31]; P = 0.55). The need for rescue noninvasive ventilation was significantly lower in the high-flow group than in the VenturiMask group: at 72 hours, 8% versus 17% (adjusted hazard ratio, 0.39 [95% CI, 0.22-0.71]; P = 0.002) and at 28 days, 12% versus 21% (adjusted hazard ratio, 0.52 [95% CI, 0.32-0.83]; P = 0.007). Conclusions: Reintubation rate did not significantly differ between patients treated with VenturiMask or high-flow oxygen after extubation. High-flow oxygen yielded less frequent use of rescue noninvasive ventilation. Clinical trial registered with www.clinicaltrials.gov (NCT02107183).

'Involve me and I learn': an experiential teaching approach to improve dyspnea awareness in medical residents

BACKGROUND

Dyspnea is a frightening and debilitating experience. It attracts less attention than pain ('dyspnea invisibility'), possibly because of its non-universal nature. We tested the impact of self-induced experimental dyspnea on medical residents.

MATERIALS AND METHODS

During a teaching session following the principles of experiential learning, emergency medicine residents were taught about dyspnea theoretically, observed experimental dyspnea in their teacher, and personally experienced self-induced dyspnea. The corresponding psychophysiological reactions were described. Immediate and 1-year evaluations were conducted to assess course satisfaction (overall 0-20 grade) and the effect on the understanding of what dyspnea represents for patients.

RESULTS

Overall, 55 emergency medicine residents participated in the study (26 men, median age 26 years). They were moderately satisfied with previous dyspnea teaching (6 [5-7] on a 0-10 numerical rating scale [NRS]) and expressed a desire for an improvement in the teaching (8 [7-9]). Immediately after the course they reported improved understanding of patients' experience (7 [6-8]), which persisted at 1 year (8 [7-9], 28 respondents). Overall course grade was 17/20 [15-18], and there were significant correlations with experimental dyspnea ratings (intensity: r = 0.318 [0.001-0.576], p = 0.043; unpleasantness: r = 0.492 [0.208-0.699], p = 0.001). In multivariate analysis, the only factor independently associated with the overall course grade was 'experiential understanding' (the experimental dyspnea-related improvement in the understanding of dyspneic patients' experience). A separate similar experiment conducted in 50 respiratory medicine residents yielded identical results.

CONCLUSIONS

This study suggests that, in advanced medical residents, the personal discovery of dyspnea can have a positive impact on the understanding of what dyspnea represents for patients. This could help fight dyspnea invisibility.

Differential Effect of Targeted Temperature Management Between 32 °C and 36 °C Following Cardiac Arrest According to Initial Severity of Illness: Insights From Two International Data Sets

BACKGROUND

Recent guidelines have emphasized actively avoiding fever to improve outcomes in patients who are comatose following resuscitation from cardiac arrest (ie, out-of-hospital cardiac arrest). However, whether targeted temperature management between 32 °C and 36 °C (TTM32-36) can improve neurologic outcome in some patients remains debated.

RESEARCH QUESTION

Is there an association between the use of TTM32-36 and outcome according to severity assessed at ICU admission using a previously derived risk score?

STUDY DESIGN AND METHODS

Data prospectively collected in the Sudden Death Expertise Center (SDEC) registry (France) between May 2011 and December 2017 and in the Resuscitation Outcomes Consortium Continuous Chest Compressions (ROC-CCC) trial (United States and Canada) between June 2011 and May 2015 were used for this study. Severity at ICU admission was assessed through a modified version of the Cardiac Arrest Hospital Prognosis (mCAHP) score, divided into tertiles of severity. The study explored associations between TTM32-36 and favorable neurologic status at hospital discharge by using multiple logistic regression as well as in tertiles of severity for each data set.

RESULTS

A total of 2,723 patients were analyzed in the SDEC data set and 4,202 patients in the ROC-CCC data set. A favorable neurologic status at hospital discharge occurred in 728 (27%) patients in the French data set and in 1,239 (29%) patients in the North American data set. Among the French data set, TTM32-36 was independently associated with better neurologic outcome in the tertile of patients with low (adjusted OR, 1.63; 95% CI, 1.15-2.30; P = .006) and high (adjusted OR, 1.94; 95% CI, 1.06-3.54; P = .030) severity according to mCAHP at ICU admission. Similar results were observed in the North American data set (adjusted ORs of 1.36 [95% CI, 1.05-1.75; P = .020] and 2.42 [95% CI, 1.38-4.24; P = .002], respectively). No association was observed between TTM32-36 and outcome in the moderate groups of the two data sets.

INTERPRETATION

TTM32-36 was significantly associated with a better outcome in patients with low and high severity at ICU admission assessed according to the mCAHP score. Further studies are needed to evaluate individualized temperature control following out-of-hospital cardiac arrest.

Low dose of morphine to relieve dyspnea in acute respiratory failure (OpiDys): protocol for a double-blind randomized controlled study

Background

Dyspnea is common and severe in intensive care unit (ICU) patients managed for acute respiratory failure. Dyspnea appears to be associated with impaired prognosis and neuropsychological sequels. Pain and dyspnea share many similarities and previous studies have shown the benefit of morphine on dyspnea in patients with end-stage onco-hematological disease and severe heart or respiratory disease. In these populations, morphine administration was safe. Here, we hypothesize that low-dose opioids may help to reduce dyspnea in patients admitted to the ICU for acute respiratory failure. The primary objective of the trial is to determine whether the administration of low-dose titrated opioids, compared to placebo, in patients admitted to the ICU for acute respiratory failure with severe dyspnea decreases the mean 24-h intensity of dyspnea score.

Methods

In this single-center double-blind randomized controlled trial with 2 parallel arms, we plan to include 22 patients (aged 18–75 years) on spontaneous ventilation with either non-invasive ventilation, high flow oxygen therapy or standard oxygen therapy admitted to the ICU for acute respiratory failure with severe dyspnea. They will be assigned after randomization with a 1:1 allocation ratio to receive in experimental arm administration of low-dose titrated morphine hydrochloride for 24 h consisting in an intravenous titration relayed subcutaneously according to a predefined protocol, or a placebo (0.9% NaCl) administered according to the same protocol in the control arm. The primary endpoint is the mean 24-h dyspnea score assessed by a visual analog scale of dyspnea.

Discussion

To our knowledge, this study is the first to evaluate the benefit of opioids on dyspnea in ICU patients admitted for acute respiratory failure.

Trial registration

ClinicalTrials.govNCT04358133. Registered on 24 April 2020.

Effect of High-Flow Nasal Cannula Oxygen vs Standard Oxygen Therapy on Mortality in Patients With Respiratory Failure Due to COVID-19: The SOHO-COVID Randomized Clinical Trial

IMPORTANCE

The benefit of high-flow nasal cannula oxygen (high-flow oxygen) in terms of intubation and mortality in patients with respiratory failure due to COVID-19 is controversial.

OBJECTIVE

To determine whether the use of high-flow oxygen, compared with standard oxygen, could reduce the rate of mortality at day 28 in patients with respiratory failure due to COVID-19 admitted in intensive care units (ICUs).

DESIGN, SETTING, AND PARTICIPANTS

The SOHO-COVID randomized clinical trial was conducted in 34 ICUs in France and included 711 patients with respiratory failure due to COVID-19 and a ratio of partial pressure of arterial oxygen to fraction of inspired oxygen equal to or below 200 mm Hg. It was an ancillary trial of the ongoing original SOHO randomized clinical trial, which was designed to include patients with acute hypoxemic respiratory failure from all causes. Patients were enrolled from January to December 2021; final follow-up occurred on March 5, 2022.

INTERVENTIONS

Patients were randomly assigned to receive high-flow oxygen (n = 357) or standard oxygen delivered through a nonrebreathing mask initially set at a 10-L/min minimum (n = 354).

MAIN OUTCOMES AND MEASURES

The primary outcome was mortality at day 28. There were 13 secondary outcomes, including the proportion of patients requiring intubation, number of ventilator-free days at day 28, mortality at day 90, mortality and length of stay in the ICU, and adverse events.

RESULTS

Among the 782 randomized patients, 711 patients with respiratory failure due to COVID-19 were included in the analysis (mean [SD] age, 61 [12] years; 214 women [30%]). The mortality rate at day 28 was 10% (36/357) with high-flow oxygen and 11% (40/354) with standard oxygen (absolute difference, -1.2% [95% CI, -5.8% to 3.4%]; P = .60). Of 13 prespecified secondary outcomes, 12 showed no significant difference including in length of stay and mortality in the ICU and in mortality up until day 90. The intubation rate was significantly lower with high-flow oxygen than with standard oxygen (45% [160/357] vs 53% [186/354]; absolute difference, -7.7% [95% CI, -14.9% to -0.4%]; P = .04). The number of ventilator-free days at day 28 was not significantly different between groups (median, 28 [IQR, 11-28] vs 23 [IQR, 10-28] days; absolute difference, 0.5 days [95% CI, -7.7 to 9.1]; P = .07). The most common adverse events were ventilator-associated pneumonia, occurring in 58% (93/160) in the high-flow oxygen group and 53% (99/186) in the standard oxygen group.

CONCLUSIONS AND RELEVANCE

Among patients with respiratory failure due to COVID-19, high-flow nasal cannula oxygen, compared with standard oxygen therapy, did not significantly reduce 28-day mortality.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04468126.

Description and Outcome of Severe Hypoglycemic Encephalopathy in the Intensive Care Unit

BACKGROUND

Disorders of consciousness due to severe hypoglycemia are rare but challenging to treat. The aim of this retrospective cohort study was to describe our multimodal neurological assessment of patients with hypoglycemic encephalopathy hospitalized in the intensive care unit and their neurological outcomes.

METHODS

Consecutive patients with disorders of consciousness related to hypoglycemia admitted for neuroprognostication from 2010 to 2020 were included. Multimodal neurological assessment included electroencephalography, somatosensory and cognitive event-related potentials, and morphological and quantitative magnetic resonance imaging (MRI) with quantification of fractional anisotropy. Neurological outcomes at 28 days, 3 months, 6 months, 1 year, and 2 years after hypoglycemia were retrieved.

RESULTS

Twenty patients were included. After 2 years, 75% of patients had died, 5% remained in a permanent vegetative state, 10% were in a minimally conscious state, and 10% were conscious but with severe disabilities (Glasgow Outcome Scale-Extended scores 3 and 4). All patients showed pathologic electroencephalography findings with heterogenous patterns. Morphological brain MRI revealed abnormalities in 95% of patients, with various localizations including cortical atrophy in 65% of patients. When performed, quantitative MRI showed decreased fractional anisotropy affecting widespread white matter tracts in all patients.

CONCLUSIONS

The overall prognosis of patients with severe hypoglycemic encephalopathy was poor, with only a small fraction of patients who slowly improved after intensive care unit discharge. Of note, patients who did not improve during the first 6 months did not recover consciousness. This study suggests that a multimodal approach capitalizing on advanced brain imaging and bedside electrophysiology techniques could improve diagnostic and prognostic performance in severe hypoglycemic encephalopathy.

Specialized Weaning Unit in the Trajectory of SARS-CoV-2 ARDS: Influence of Limb Muscle Strength on Decannulation and Rehabilitation

BACKGROUND

Patients with ARDS due to COVID-19 may require tracheostomy and transfer to a weaning center. To date, data on the outcome of these patients are scarce. The objectives of this study were to determine the factors associated with time to decannulation and limb-muscle strength recovery.

METHODS

This was an observational retrospective study of subjects with COVID-19-related ARDS requiring tracheostomy after prolonged ventilation, who were subsequently transferred to a weaning center from April 4, 2020-May 30, 2020.

RESULTS

Forty-three subjects were included. Median age (interquartile range) was 61 (48-66) y; 81% were men, and median body mass index (BMI) was 30 (26-35) kg/m². Tracheostomy was performed after a median of 19 (12-27) d of mechanical ventilation, and the median ICU length of stay prior to transfer to the weaning center was 30 (21-46) d. On admission to the weaning center, the median Medical Research Council (MRC) score was 36 (27-44). Time to decannulation was 9 (7-18) d after admission to the weaning center. The only factor independently associated with early decannulation was the MRC score on admission to the weaning center (odds ratio 1.16 [95% CI 1.06-1.31], P = .005). Two factors were independently associated with MRC gain ≥ 10: BMI (odds ratio 0.88 [95% CI 0.76-0.99], P = .045) and MRC on admission (odds ratio 0.91 [95% CI 0.82-0.98], P = .03. Three months after admission to the weaning center, 40 subjects (93%) were weaned from mechanical ventilation and 36 (84%) had returned home.

CONCLUSIONS

MRC score at weaning center admission predicted both early decannulation and limb-muscle strength recovery.

Prognostic Value of the Intensive Care Respiratory Distress Observation Scale on ICU Admission

BACKGROUND

The association between dyspnea and mortality has not been demonstrated in the ICU setting. We tested the hypothesis that dyspnea (self-reported respiratory discomfort) or its observational correlates (5-item intensive care Respiratory Distress Observation Scale [IC-RDOS]) assessed on ICU admission would be associated with ICU mortality.

METHODS

Ancillary analysis of single-center data prospectively collected from 220 communicative ICU subjects allocated to a derivation cohort of 120 subjects and a separate validation cohort of 100 subjects. Dyspnea was assessed dichotomously (yes/no), with a dyspnea visual analog scale (measured in mm), and IC-RDOS was calculated. Multivariate logistic regression was used to identify factors associated with ICU and hospital mortality.

RESULTS

Dyspnea was reported by 69 (58%; median 45 [interquartile range [IQR] 32-60] mm) and 47 (47%; 38 [IQR 26-48] mm) subjects in the derivation and validation cohorts, respectively. IC-RDOS was 2.3 (1.2-3.1) and 2.4 (1.3-2.8), respectively. IC-RDOS values were higher in subjects with dyspnea than in subjects without dyspnea in both the derivation cohort (2.6 [2.2-4.6] vs 1.4 [0.9-2.4], P < .001) and the validation cohort (2.6 [2.3-4.4] vs 2.2 [1.0-2.8], P < .001). On multivariate analysis of the derivation cohort, admission for hemorrhagic shock (odds ratio 13.98), IC-RDOS (odds ratio 1.77), and Simplified Acute Physiology Score II (odds ratio 1.10) was associated with ICU mortality. Areas under the receiving operating characteristic curve of IC-RDOS to predict ICU mortality were 0.785 and 0.794 in the derivation and validation cohorts, respectively.

CONCLUSIONS

IC-RDOS, an observational correlate of dyspnea, but not dyspnea itself, was associated with higher mortality in ICU subjects.

Organisation et rôle d’un Service de Réadaptation Post-Réanimation (SRPR) à orientation respiratoire dans la trajectoire d’un patient de réanimation

Les services de réadaptation post-réanimation à orientation respiratoire sont des structures de soins offrant un nouveau modèle de prise en charge spécialisée pour les patients présentant un sevrage ventilatoire prolongé et/ou une défaillance critique persistante à l’issu d’un séjour prolongé en réanimation. La principale défaillance chronique persistante est la dépendance ventilatoire prolongée à laquelle s’associe généralement une constellation « syndromique » de modifications physiologiques, conséquences du séjour en réanimation, comme la dénutrition, la neuromyopathie (locomotion, déglutition), le delirium, les lésions cutanées et un état d’immunodépression. Au-delà de l’activité spécifique de sevrage ventilatoire et du retrait de la canule de trachéotomie, les missions de soins au SRPR sont complexes et multidisciplinaires impliquant une prise en charge nutritionnelle, une réhabilitation motrice, la gestion des comorbidités (décompensation), le soulagement des symptômes, une prise en charge psychologiques, et la planification du projet de soin en concertation avec le patient et son entourage. Cette mise au point aborde le concept de défaillance critique persistante post-réanimation et des enjeux de santé publique qu’il représente, retrace l’historique du développement des SRPR à orientation respiratoire ainsi que leurs principaux éléments structurels et de fonctionnement, pour enfin développer les grands axes de prise en charge thérapeutique.

Dyspnea and the electromyographic activity of inspiratory muscles during weaning from mechanical ventilation

Rationale

Dyspnea, a key symptom of acute respiratory failure, is not among the criteria for spontaneous breathing trial (SBT) failure. Here, we sought (1) to determine whether dyspnea is a reliable failure criterion for SBT failure; (2) to quantify the relationship between dyspnea and the respective electromyographic activity of the diaphragm (EMGdi), the parasternal (EMGpa) and the Alae nasi (EMGan).

Methods

Mechanically ventilated patients undergoing an SBT were included. Dyspnea intensity was measured by the Dyspnea-Visual Analogic Scale (Dyspnea-VAS) at the initiation and end of the SBT. During the 30-min SBT or until SBT failure, the EMGdi was continuously measured with a multi-electrode nasogastric catheter and the EMGan and EMGpa with surface electrodes.

Results

Thirty-one patients were included, SAPS 2 (median [interquartile range]) 53 (37‒74), mechanically ventilated for 6 (3‒10) days. Seventeen patients (45%) failed the SBT. The increase in Dyspnea-VAS along the SBT was higher in patients who failed (6 [4‒8] cm) than in those who passed (0 [0‒1] cm, p = 0.01). The area under the receiver operating characteristics curve for Dyspnea-VAS was 0.909 (0.786–1.032). The increase in Dyspnea-VAS was significantly correlated to the increase in EMGan (Rho = 0.42 [0.04‒0.70], p < 0.05), but not to the increase in EMGpa (Rho = − 0.121 [− 0.495 to − 0.290], p = 0.555) and EMGdi (Rho = − 0.26 [− 0.68 to 0.28], p = 0.289).

Conclusion

Dyspnea is a reliable criterion of SBT failure, suggesting that Dyspnea-VAS could be used as a monitoring tool of the SBT. In addition, dyspnea seems to be more closely related to the electromyographic activity of the Alae nasi than of the diaphragm.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01025-5.

Respiratory distress observation scales to predict weaning outcome

Background

Whether dyspnea is present before starting a spontaneous breathing trial (SBT) and whether it may affect the outcome of the SBT is unknown. Mechanical Ventilation—Respiratory Distress Observation Scale (MV-RDOS) has been proposed as a reliable surrogate of dyspnea in non-communicative intubated patients. In the present study, we sought (1) to describe the evolution of the MV-RDOS during a SBT and (2) to investigate whether MV-RDOS can predict the outcome of the SBT.

Methods

Prospective, single-center study in a twenty-two bed ICU in a tertiary center. Patients intubated since more 48 h who had failed a first SBT were eligible if they meet classical readiness to wean criteria. The MV-RDOS was assessed before, at 2-min, 15-min and 30-min (end) of the SBT. The presence of clinically important dyspnea was inferred by a MV-RDOS value ≥  2.6.

Results

Fifty-eight patients (age 63 [51–70], SAPS II 66 [51–76]; med [IQR]) were included. Thirty-three (57%) patients failed the SBT, whose 18 (55%) failed before 15-min. Twenty-five (43%) patients successfully passed the SBT. A MV-RDOS ≥ 2.6 was present in ten (17%) patients before to start the SBT. All these ten patients subsequently failed the SBT. A MV-RDOS ≥ 2.6 at 2-min predicted a SBT failure with a 51% sensibility and a 88% specificity (AUC 0.741 95% confidence interval [CI] 0.616–0.866, p = 0.002). Best cut-off value at 2-min was 4.3 and predicted SBT failure with a 27% sensibility and a 96% specificity.

Conclusion

Despite patients met classical readiness to wean criteria, respiratory distress assessed with the MV-RDOS was frequent at the beginning of SBT. Measuring MV-RDOS before to initiate a SBT could avoid undue procedure and reduce patient’s exposure to unnecessary mechanical ventilation weaning failure and distress.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04028-7.

Randomized Clinical Study of Temporary Transvenous Phrenic Nerve Stimulation in Difficult-to-Wean Patients

Rationale: Diaphragm dysfunction is frequently observed in critically ill patients with difficult weaning from mechanical ventilation. Objectives: To evaluate the effects of temporary transvenous diaphragm neurostimulation on weaning outcome and maximal inspiratory pressure. Methods: Multicenter, open-label, randomized, controlled study. Patients aged ⩾18 years on invasive mechanical ventilation for ⩾4 days and having failed at least two weaning attempts received temporary transvenous diaphragm neurostimulation using a multielectrode stimulating central venous catheter (bilateral phrenic stimulation) and standard of care (treatment) (n = 57) or standard of care (control) (n = 55). In seven patients, the catheter could not be inserted, and in seven others, pacing therapy could not be delivered; consequently, data were available for 43 patients. The primary outcome was the proportion of patients successfully weaned. Other endpoints were mechanical ventilation duration, 30-day survival, maximal inspiratory pressure, diaphragm-thickening fraction, adverse events, and stimulation-related pain. Measurements and Main Results: The incidences of successful weaning were 82% (treatment) and 74% (control) (absolute difference [95% confidence interval (CI)], 7% [-10 to 25]), P = 0.59. Mechanical ventilation duration (mean ± SD) was 12.7 ± 9.9 days and 14.1 ± 10.8 days, respectively, P = 0.50; maximal inspiratory pressure increased by 16.6 cm H₂O and 4.8 cm H₂O, respectively (difference [95% CI], 11.8 [5 to 19]), P = 0.001; and right hemidiaphragm thickening fraction during unassisted spontaneous breathing was +17% and -14%, respectively, P = 0.006, without correlation with changes in maximal inspiratory pressure. Serious adverse event frequency was similar in both groups. Median stimulation-related pain in the treatment group was 0 (no pain). Conclusions: Temporary transvenous diaphragm neurostimulation did not increase the proportion of successful weaning from mechanical ventilation. It was associated with a significant increase in maximal inspiratory pressure, suggesting reversal of the course of diaphragm dysfunction. Clinical trial registered with www.clinicaltrials.gov (NCT03096639) and the European Database on Medical Devices (CIV-17-06-020004).

Comparison of 8 versus 15 days of antibiotic therapy for Pseudomonas aeruginosa ventilator-associated pneumonia in adults: a randomized, controlled, open-label trial

PURPOSE

Compared to long duration of antibiotic therapy, a short duration has a comparable clinical efficacy for ventilator-associated pneumonia (VAP), with the exception of documented VAP of non-fermenting Gram-negative bacilli (NF-GNB), including Pseudomonas aeruginosa (PA). We aimed to assess the non-inferiority of a short duration of antibiotics (8 days) vs. prolonged antibiotic therapy (15 days) in VAP due to PA (PA-VAP).

METHODS

We conducted a nationwide, randomized, open-labeled, multicenter, non-inferiority trial to evaluate optimal duration of antibiotic treatment in PA-VAP. Eligible patients were adults with diagnosis of PA-VAP and randomly assigned in 1:1 ratio to receive a short-duration treatment (8 days) or a long-duration treatment (15 days). A pre-specified analysis was used to assess a composite endpoint combining mortality and PA-VAP recurrence rate during hospitalization in the intensive care unit (ICU) within 90 days.

RESULTS

In intention-to-treat population (n = 186), the percentage of patients who reached the composite endpoint was 25.5% (N = 25/98) in the 15-day group versus 35.2% (N = 31/88) in the 8-day group (difference 9.7%, 90% confidence interval (CI) 0.0-21.2%). The percentage of recurrence of PA-VAP during the ICU stay was 9.2% in the 15-day group versus 17% in the 8-day group. The two groups had similar median days of mechanical ventilation, of ICU stay, number of extra pulmonary infections and acquisition of multidrug-resistant (MDR) pathogens during ICU stay.

CONCLUSIONS

Our study showed no differences in the composite or separate outcomes (90-day mortality or VAP recurrence) between short- and long-duration treatments for PA-VAP. However, the lack of power limits the interpretation of this study.

Severe but reversible impaired diaphragm function in septic mechanically ventilated patients

Background

Whether sepsis-associated diaphragm dysfunction may improve despite the exposure of mechanical ventilation in critically ill patients is unclear. This study aims at describing the diaphragm function time course of septic and non-septic mechanically ventilated patients.

Methods

Secondary analysis of two prospective observational studies of mechanically ventilated patients in whom diaphragm function was assessed twice: within the 24 h after intubation and when patients were switched to pressure support mode, by measuring the endotracheal pressure in response to bilateral anterior magnetic phrenic nerve stimulation (Ptr,stim). Change in diaphragm function was expressed as the difference between Ptr,stim measured under pressure support mode and Ptr,stim measured within the 24 h after intubation. Sepsis was defined according to the Sepsis-3 international guidelines upon inclusion. In a sub-group of patients, the right hemidiaphragm thickness was measured by ultrasound.

Results

Ninety-two patients were enrolled in the study. Sepsis upon intubation was present in 51 (55%) patients. In septic patients, primary reason for ventilation was acute respiratory failure related to pneumonia (37/51; 73%). In non-septic patients, main reasons for ventilation were acute respiratory failure not related to pneumonia (16/41; 39%), coma (13/41; 32%) and cardiac arrest (6/41; 15%). Ptr,stim within 24 h after intubation was lower in septic patients as compared to non-septic patients: 6.3 (4.9–8.7) cmH₂O vs. 9.8 (7.0–14.2) cmH₂O (p = 0.004), respectively. The median (interquartile) duration of mechanical ventilation between first and second diaphragm evaluation was 4 (2–6) days in septic patients and 3 (2–4) days in non-septic patients (p = 0.073). Between first and second measurements, the change in Ptr,stim was + 19% (− 13–61) in septic patients and − 7% (− 40–12) in non-septic patients (p = 0.005). In the sub-group of patients with ultrasound measurements, end-expiratory diaphragm thickness decreased in both, septic and non-septic patients. The 28-day mortality was higher in patients with decrease or no change in diaphragm function.

Conclusion

Septic patients were associated with a more severe but reversible impaired diaphragm function as compared to non-septic patients. Increase in diaphragm function was associated with a better survival.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01005-9.

EXpert consensus On Diaphragm UltraSonography in the critically ill (EXODUS): a Delphi consensus statement on the measurement of diaphragm ultrasound-derived parameters in a critical care setting

Background

Diaphragm ultrasonography is rapidly evolving in both critical care and research. Nevertheless, methodologically robust guidelines on its methodology and acquiring expertise do not, or only partially, exist. Therefore, we set out to provide consensus-based statements towards a universal measurement protocol for diaphragm ultrasonography and establish key areas for research.

Methods

To formulate a robust expert consensus statement, between November 2020 and May 2021, a two-round, anonymous and online survey-based Delphi study among experts in the field was performed. Based on the literature review, the following domains were chosen: “Anatomy and physiology”, “Transducer Settings”, “Ventilator Impact”, “Learning and expertise”, “Daily practice” and “Future directions”. Agreement of ≥ 68% (≥ 10 panelists) was needed to reach consensus on a question.

Results

Of 18 panelists invited, 14 agreed to participate in the survey. After two rounds, the survey included 117 questions of which 42 questions were designed to collect arguments and opinions and 75 questions aimed at reaching consensus. Of these, 46 (61%) consensus was reached. In both rounds, the response rate was 100%. Among others, there was agreement on measuring thickness between the pleura and peritoneum, using > 10% decrease in thickness as cut-off for atrophy and using 40 examinations as minimum training to use diaphragm ultrasonography in clinical practice. In addition, key areas for research were established.

Conclusion

This expert consensus statement presents the first set of consensus-based statements on diaphragm ultrasonography methodology. They serve to ensure high-quality and homogenous measurements in daily clinical practice and in research. In addition, important gaps in current knowledge and thereby key areas for research are established.

Trial registration The study was pre-registered on the Open Science Framework with registration digital object identifier https://doi.org/10.17605/OSF.IO/HM8UG.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03975-5.

Very late intubation in COVID-19 patients: a forgotten prognosis factor?

Description of all consecutive critically ill COVID 19 patients hospitalized in ICU in University Hospital of Guadeloupe and outcome according to delay between steroid therapy initiation and mechanical ventilation onset. Very late mechanical ventilation defined as intubation after day 7 of dexamethasone therapy was associated with grim prognosis and a high mortality rate of 87%.