Effect of High-Flow Nasal Oxygen vs Standard Oxygen on 28-Day Mortality in Immunocompromised Patients With Acute Respiratory Failure: The HIGH Randomized Clinical Trial

Oxygen therapy in acute hypoxemic respiratory failure: guidelines from the SRLF-SFMU consensus conference

INTRODUCTION

Although largely used, the place of oxygen therapy and its devices in patients with acute hypoxemic respiratory failure (ARF) deserves to be clarified. The French Intensive Care Society (Société de Réanimation de Langue Française, SRLF) and the French Emergency Medicine Society (Société Française de Médecine d'Urgence, SFMU) organized a consensus conference on oxygen therapy in ARF (excluding acute cardiogenic pulmonary oedema and hypercapnic exacerbation of chronic obstructive diseases) in December 2023.

METHODS

A committee without any conflict of interest (CoI) with the subject defined 7 generic questions and drew up a list of sub questions according to the population, intervention, comparison and outcomes (PICO) model. An independent work group reviewed the literature using predefined keywords. The quality of the data was assessed using the GRADE methodology. Fifteen experts in the field from both societies proposed their own answers in a public session and answered questions from the jury (a panel of 16 critical-care and emergency medicine physicians, nurses and physiotherapists without any CoI) and the public. The jury then met alone for 48 h to write its recommendations.

RESULTS

The jury provided 22 statements answering 11 questions: in patients with ARF (1) What are the criteria for initiating oxygen therapy? (2) What are the targets of oxygen saturation? (3) What is the role of blood gas analysis? (4) When should an arterial catheter be inserted? (5) Should standard oxygen therapy, high-flow nasal cannula oxygen therapy (HFNC) or continuous positive airway pressure (CPAP) be preferred? (6) What are the indications for non-invasive ventilation (NIV)? (7) What are the indications for invasive mechanical ventilation? (8) Should awake prone position be used? (9) What is the role of physiotherapy? (10) Which criteria necessarily lead to ICU admission? (11) Which oxygenation device should be preferred for patients for whom a do-not-intubate decision has been made?

CONCLUSION

These recommendations should optimize the use of oxygen during ARF.

When to intubate in acute hypoxaemic respiratory failure? Options and opportunities for evidence-informed decision making in the intensive care unit

The optimal timing of intubation in acute hypoxaemic respiratory failure is uncertain and became a point of controversy during the COVID-19 pandemic. Invasive mechanical ventilation is a potentially life-saving intervention but carries substantial risks, including injury to the lungs and diaphragm, pneumonia, intensive care unit-acquired muscle weakness, and haemodynamic impairment. In deciding when to intubate, clinicians must balance premature exposure to the risks of ventilation with the potential harms of unassisted breathing, including disease progression and worsening multiorgan failure. Currently, the optimal timing of intubation is unclear. In this Personal View, we examine a range of parameters that could serve as triggers to initiate invasive mechanical ventilation. The utility of a parameter (eg, the ratio of arterial oxygen tension to fraction of inspired oxygen) to predict the likelihood of a patient undergoing intubation does not necessarily mean that basing the timing of intubation on that parameter will improve therapeutic outcomes. We examine options for clinical investigation to make progress on establishing the optimal timing of intubation.

A Comprehensive Review on High-Flow Nasal Cannula Oxygen Therapy in Critical Care: Evidence-Based Insights and Future Directions

High-flow nasal cannula (HFNC) therapy has emerged as a significant advancement in respiratory support, offering a non-invasive alternative to traditional oxygen delivery methods in critical care settings. This review comprehensively evaluates HFNC therapy, focusing on its definition, historical evolution, and current clinical applications. HFNC therapy delivers humidified and heated oxygen at high flow rates through a nasal cannula, enhancing oxygenation and patient comfort. The review highlights the physiological mechanisms underlying HFNC and its efficacy in managing acute respiratory failure, chronic obstructive pulmonary disease exacerbations, and postoperative respiratory support. Key findings from clinical trials and meta-analyses are discussed, emphasizing HFNC's advantages over conventional methods, such as reduced intubation rates and shorter ICU stays. The review also addresses safety considerations, including potential risks and complications associated with HFNC therapy. Furthermore, it explores future directions for research and technological advancements aimed at optimizing HFNC use in diverse patient populations. This review aims to provide evidence-based insights to inform clinical practice and guide future investigations in respiratory therapy.

Respiratory support in the emergency department: A systematic review and meta-analysis

BACKGROUND

An estimated 20% of emergency department (ED) patients require respiratory support (RS). Evidence suggests that nasal high flow (NHF) reduces RS need.

AIMS

This review compared NHF to conventional oxygen therapy (COT) or noninvasive ventilation (NIV) in adult ED patients.

METHOD

The systematic review (SR) and meta-analysis (MA) methods reflect the Cochrane Collaboration methodology. Six databases were searched for randomized controlled trials (RCTs) comparing NHF to COT or NIV use in the ED. Three summary estimates were reported: (1) need to escalate care, (2) mortality, and (3) adverse events (AEs).

RESULTS

This SR and MA included 18 RCTs (n = 1874 participants). Two of the five MA conclusions were statistically significant. Compared with COT, NHF reduced the risk of escalation by 45% (RR 0.55; 95% CI [0.33, 0.92], p = .02, NNT = 32); however, no statistically significant differences in risk of mortality (RR 1.02; 95% CI [0.68, 1.54]; p = .91) and AE (RR 0.98; 95% CI [0.61, 1.59]; p = .94) outcomes were found. Compared with NIV, NHF increased the risk of escalation by 60% (RR 1.60; 95% CI [1.10, 2.33]; p = .01); mortality risk was not statistically significant (RR 1.23, 95% CI [0.78, 1.95]; p = .37).

LINKING EVIDENCE TO ACTION

Evidence-based decision-making regarding RS in the ED is challenging. ED clinicians have at times had to rely on non-ED evidence to support their practice. Compared with COT, NHF was seen to be superior and reduced the risk of escalation. Conversely, for this same outcome, NIV was superior to NHF. However, substantial clinical heterogeneity was seen in the NIV delivered. Research considering NHF versus NIV is needed. COVID-19 has exposed the research gaps and slowed the progress of ED research.

High-flow nasal oxygen therapy compared with conventional oxygen therapy in hospitalised patients with respiratory illness: a systematic review and meta-analysis

BACKGROUND

High-flow nasal oxygen therapy (HFNO) is used in diverse hospital settings to treat patients with acute respiratory failure (ARF). This systematic review aims to summarise the evidence regarding any benefits HFNO therapy has compared with conventional oxygen therapy (COT) for patients with ARF.

METHODS

Three databases (Embase, Medline and CENTRAL) were searched on 22 March 2023 for studies evaluating HFNO compared with COT for the treatment of ARF, with the primary outcome being hospital mortality and secondary outcomes including (but not limited to) escalation to invasive mechanical ventilation (IMV) or non-invasive ventilation (NIV). Risk of bias was assessed using the Cochrane risk-of-bias tool (randomised controlled trials (RCTs)), ROBINS-I (non-randomised trials) or Newcastle-Ottawa Scale (observational studies). RCTs and observational studies were pooled together for primary analyses, and secondary analyses used RCT data only. Treatment effects were pooled using the random effects model.

RESULTS

63 studies (26 RCTs, 13 cross-over and 24 observational studies) were included, with 10 230 participants. There was no significant difference in the primary outcome of hospital mortality (risk ratio, RR 1.08, 95% CI 0.93 to 1.26; p=0.29; 17 studies, n=5887) between HFNO and COT for all causes ARF. However, compared with COT, HFNO significantly reduced the overall need for escalation to IMV (RR 0.85, 95% CI 0.76 to 0.95 p=0.003; 39 studies, n=8932); and overall need for escalation to NIV (RR 0.70, 95% CI 0.50 to 0.98; p=0.04; 16 studies, n=3076). In subgroup analyses, when considering patients by illness types, those with acute-on-chronic respiratory failure who received HFNO compared with COT had a significant reduction in-hospital mortality (RR 0.58, 95% CI 0.37 to 0.91; p=0.02).

DISCUSSION

HFNO was superior to COT in reducing the need for escalation to both IMV and NIV but had no impact on the primary outcome of hospital mortality. These findings support recommendations that HFNO may be considered as first-line therapy for ARF.

PROSPERO REGISTRATION NUMBER

CRD42021264837.

Clinical Profiles, Laboratory Biomarkers, and Mortality in Cancer Patients with Lower Respiratory Tract Infections: A Prospective Cohort Study

Respiratory tract infections (RTIs) pose a substantial health burden worldwide, especially among immunocompromised groups like cancer patients. The aim of this prospective cohort study was to explore lower respiratory tract infections in cancer patients. We followed 107 cases with clinically or radiologically suspected lower respiratory tract infections until discharge or death, comprising 65 males and 42 females across diverse age groups. Clinical evaluations, including patient history, examination, and malignancy diagnosis, were conducted. Nasopharyngeal swabs (NPSs), sputum samples, and blood samples were collected within 24 h of symptom onset. Multiplex Real-Time PCR allowed for the simultaneous detection of viral, bacterial, and fungal infections, while conventional microbiological culture methods were used for bacterial and fungal analysis. SARS-CoV-2 infection was excluded in all of the enrolled patients using real-time RT-PCR. Hematological and biochemical analyses included hemoglobin, lymphocyte, neutrophil, and platelet counts, along with ALT, AST, creatinine, and CRP levels. Significant differences were noted in clinical presentations, management outcomes, and prognostic markers among patients with different hematological malignancies. Distinct clinical profiles were identified for leukemia, lymphoma, and solid tumors, with variations in age distribution and symptom prevalence. ICU admission rates varied significantly, with solid tumor patients exhibiting higher rates. The hematological and biochemical biomarkers differed across malignancies, with notable associations between lymphopenia, thrombocytopenia, and mortality following respiratory episodes. This study highlights the critical role of rapid pathogen detection and infection control measures in safeguarding vulnerable cancer patients from nosocomial transmission.

High-flow nasal cannula oxygen reduced hypoxemia in patients undergoing gastroscopy under general anesthesia at ultra-high altitude: a randomized controlled trial

BACKGROUND

Hypoxemia can occur in people at ultra-high altitude (above 3500 m) even at rest, and patients undergoing gastroscopy under general anesthesia have higher risk of hypoxemia. Supplementary oxygen via standard nasal cannula (SNC) is the standard of care for most patients who undergo gastroscopy under general anesthesia, which provides oxygen flow up to 15 L/min. High-flow nasal cannula (HFNC) could deliver oxygen at a rate up to 60 L/min, which is recommended by the American Society of Anesthesiologists Practice Guidelines. We speculated that the benefit with HFNC is more prominent in high-altitude areas, and aimed to compare the incidence of hypoxemia during gastroscopy under general anesthesia at ultra-high altitude with oxygen supply via either HFNC or SNC.

METHODS

The trial was registered at at Chinese Clinical Trial Registry (ChiCTR2100045513; date of registration on 18/04/2021). Adult patients undergoing gastroscopy with anesthesia (estimated duration of anesthesia at ≥ 15 min) were randomized at a 1:1 ratio to receive HFNC oxygen or SNC oxygen. The primary outcome was hypoxemia (SpO2 < 90% for any duration). Secondary outcomes included severe hypoxemia (SpO2 < 75% for any duration or SpO2 < 90% but ≥ 75% for ≥ 60 s) and hypotension, as defined by reduction of mean arterial blood pressure by ≥ 25% from the baseline.

RESULTS

A total of 262 patients were enrolled: 129 in the HFNC group and 133 in the SNC group. All patients received the designated intervention. Student's t-test, Mann-Whitney U test and χ2 test were employed in the study. The rate of hypoxemia was 9.3% (12/129) in the HFNC group versus 36.8% (49/133) in the SNC group [risk ratio (95% confidence interval): 0.25(0.14-0.45); P < 0.001). The HFNC group also had lower rate of severe hypoxemia [0.0% (0/129) versus 11.3% (15/133); risk ratio (95% confidence interval): 0.03(0.00-0.55); P < 0.001, respectively]. The rate of hypotension did not differ between the 2 groups [22.5% (29/129) in HFNC group versus 21.1% (28/133) in SNC group; risk ratio (95% confidence interval): 1.07(0.67-1.69) ; P = 0.779].

CONCLUSION

HFNC oxygen reduced the incidence of hypoxemia during anesthesia in adult patients undergoing gastroscopy at ultra-high altitude.

Dyspnea is severe and associated with a higher intubation rate in de novo acute hypoxemic respiratory failure

BACKGROUND

Dyspnea is a key symptom of de novo acute hypoxemic respiratory failure. This study explores dyspnea and its association with intubation and mortality in this population.

METHODS

This was a secondary analysis of a multicenter, randomized, controlled trial. Dyspnea was quantified by a visual analog scale (dyspnea-VAS) from zero to 100 mm. Dyspnea was measured in 259 of the 310 patients included. Factors associated with intubation were assessed with a competing risks model taking into account ICU discharge. The Cox model was used to evaluate factors associated with 90-day mortality.

RESULTS

At baseline (randomization in the parent trial), median dyspnea-VAS was 46 (interquartile range, 16-65) mm and was ≥ 40 mm in 146 patients (56%). The intubation rate was 45%. Baseline variables independently associated with intubation were moderate (dyspnea-VAS 40-64 mm) and severe (dyspnea-VAS ≥ 65 mm) dyspnea at baseline (sHR 1.96 and 2.61, p = 0.023), systolic arterial pressure (sHR 2.56, p < 0.001), heart rate (sHR 1.94, p = 0.02) and PaO2/FiO2 (sHR 0.34, p = 0.028). 90-day mortality was 20%. The cumulative probability of survival was lower in patients with baseline dyspnea-VAS ≥ 40 mm (logrank test, p = 0.049). Variables independently associated with mortality were SAPS 2 ≥ 25 (p < 0.001), moderate-to-severe dyspnea at baseline (p = 0.073), PaO2/FiO2 (p = 0.118), and treatment arm (p = 0.046).

CONCLUSIONS

In patients admitted to the ICU for de novo acute hypoxemic respiratory failure, dyspnea is associated with a higher risk of intubation and with a higher mortality.

TRIAL REGISTRATION

clinicaltrials.gov Identifier # NCT01320384.

Effect of immediate initiation of invasive ventilation on mortality in acute hypoxemic respiratory failure: a target trial emulation

PURPOSE

Invasive ventilation is a fundamental treatment in intensive care but its precise timing is difficult to determine. This study aims at assessing the effect of initiating invasive ventilation versus waiting, in patients with hypoxemic respiratory failure without immediate reason for intubation on one-year mortality.

METHODS

Emulation of a target trial to estimate the benefit of immediately initiating invasive ventilation in hypoxemic respiratory failure, versus waiting, among patients within the first 48-h of hypoxemia. The eligible population included non-intubated patients with SpO2/FiO2 ≤ 200 and SpO2 ≤ 97%. The target trial was emulated using a single-center database (MIMIC-IV) which contains granular information about clinical status. The hourly probability to receive mechanical ventilation was continuously estimated. The hazard ratios for the primary outcome, one-year mortality, and the secondary outcome, 30-day mortality, were estimated using weighted Cox models with stabilized inverse probability weights used to adjust for measured confounding.

RESULTS

2996 Patients fulfilled the inclusion criteria of whom 792 were intubated within 48 h. Among the non-invasive support devices, the use of oxygen through facemask was the most common (75%). Compared to patients with the same probability of intubation but who were not intubated, intubation decreased the hazard of dying for the first year after ICU admission HR 0.81 (95% CI 0.68-0.96, p = 0.018). Intubation was associated with a 30-day mortality HR of 0.80 (95% CI 0.64-0.99, p = 0.046).

CONCLUSION

The initiation of mechanical ventilation in patients with acute hypoxemic respiratory failure reduced the hazard of dying in this emulation of a target trial.

[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.

High-flow nasal oxygen in infants and children for early respiratory management of pneumonia-induced acute hypoxemic respiratory failure: the CENTURI randomized clinical trial

Objective

To compare the effectiveness of early high-flow nasal cannula (HFNC) and low-flow oxygen support (LFOS) in children under 5 years with acute hypoxemic respiratory failure (AHRF) due to severe community-acquired pneumonia in low-middle-income countries.

Methods

An open-label randomized clinical trial enrolled children aged 2-59 months with AHRF due to severe community-acquired pneumonia and randomized into HFNC and LFOS. In the LFOS group, the patient received cold wall oxygen humidified by bubbling through sterile water administered through simple nasal prongs at a fixed flow rate of 2 L/min. In the HFNC group, the patient received humidified, heated (37 °C), high-flow oxygen at a flow rate assigned based on weight range, with a titratable oxygen fraction. The primary outcome was treatment failure in 72 h (escalating the respiratory support method using any modality other than primary intervention).

Results

Data was analyzed intention-to-treat (HFNC = 124; LFOS = 120). Median (IQR) age was 12 (6-20) and 11 (6-27) months, respectively. Treatment failure occurred in a significantly lower proportion in the HFNC group (7.3%, n = 9/124) as compared to the LFOS group (20%, n = 24/120) (relative risk = 0.36, 95% CI 0.18 to 0.75; p = 0.004; adjusted hazard ratio 0.34, 95% CI 0.16 to 0.73; p = 0.006). The intubation rate was significantly lower in the HFNC group (7.3%, n = 9/124 vs. 16.7%, n = 20/120; relative risk = 0.44, 95% CI 0.21 to 0.92, p = 0.023). There were no significant differences noted in other secondary outcomes. No mortality occurred.

Conclusion

High-flow nasal cannula oxygen therapy used as early respiratory support in children under 5 years with acute hypoxemic respiratory failure due to severe community-acquired pneumonia was associated with significantly lower treatment failure compared with standard low-flow oxygen support.

Trial registration

CTRI/2016/04/006788. Registered 01 April 2016, https://ctri.nic.in/Clinicaltrials/advsearch.php.

Supplementary Information

The online version contains supplementary material available at 10.1007/s44253-024-00031-8.

Severe Community-Acquired Pneumonia in Immunocompromised Patients

Due to higher survival rates with good quality of life, related to new treatments in the fields of oncology, hematology, and transplantation, the number of immunocompromised patients is increasing. But these patients are at high risk of intensive care unit admission because of numerous complications. Acute respiratory failure due to severe community-acquired pneumonia is one of the leading causes of admission. In this setting, the need for invasive mechanical ventilation is up to 60%, associated with a high hospital mortality rate of around 40 to 50%. A wide range of pathogens according to the reason of immunosuppression is associated with severe pneumonia in those patients: documented bacterial pneumonia represents a third of cases, viral and fungal pneumonia both account for up to 15% of cases. For patients with an undetermined etiology despite comprehensive diagnostic workup, the hospital mortality rate is very high. Thus, a standardized diagnosis strategy should be defined to increase the diagnosis rate and prescribe the appropriate treatment. This review focuses on the benefit-to-risk ratio of invasive or noninvasive strategies, in the era of omics, for the management of critically ill immunocompromised patients with severe pneumonia in terms of diagnosis and oxygenation.

Severe Community-Acquired Pneumonia: Noninvasive Mechanical Ventilation, Intubation, and HFNT

Severe acute respiratory failure (ARF) is a major issue in patients with severe community-acquired pneumonia (CAP). Standard oxygen therapy is the first-line therapy for ARF in the less severe cases. However, respiratory supports may be delivered in more severe clinical condition. In cases with life-threatening ARF, invasive mechanical ventilation (IMV) will be required. Noninvasive strategies such as high-flow nasal therapy (HFNT) or noninvasive ventilation (NIV) by either face mask or helmet might cover the gap between standard oxygen and IMV. The objective of all the supporting measures for ARF is to gain time for the antimicrobial treatment to cure the pneumonia. There is uncertainty regarding which patients with severe CAP are most likely to benefit from each noninvasive support strategy. HFNT may be the first-line approach in the majority of patients. While NIV may be relatively contraindicated in patients with excessive secretions, facial hair/structure resulting in air leaks or poor compliance, NIV may be preferable in those with increased work of breathing, respiratory muscle fatigue, and congestive heart failure, in which the positive pressure of NIV may positively impact hemodynamics. A trial of NIV might be considered for select patients with hypoxemic ARF if there are no contraindications, with close monitoring by an experienced clinical team who can intubate patients promptly if they deteriorate. In such cases, individual clinician judgement is key to choose NIV, interface, and settings. Due to the paucity of studies addressing IMV in this population, the protective mechanical ventilation strategies recommended by guidelines for acute respiratory distress syndrome can be reasonably applied in patients with severe CAP.

Acute Respiratory Distress Syndrome: Definition, Diagnosis, and Routine Management

Acute respiratory distress syndrome (ARDS) is an acute inflammatory lung injury characterized by severe hypoxemic respiratory failure, bilateral opacities on chest imaging, and low lung compliance. ARDS is a heterogeneous syndrome that is the common end point of a wide variety of predisposing conditions, with complex pathophysiology and underlying mechanisms. Routine management of ARDS is centered on lung-protective ventilation strategies such as low tidal volume ventilation and targeting low airway pressures to avoid exacerbation of lung injury, as well as a conservative fluid management strategy.

Challenges for a broad international implementation of the current severe community-acquired pneumonia guidelines

Severe community-acquired pneumonia (sCAP) remains one of the leading causes of admission to the intensive care unit, thus consuming a large share of resources and is associated with high mortality rates worldwide. The evidence generated by clinical studies in the last decade was translated into recommendations according to the first published guidelines focusing on severe community-acquired pneumonia. Despite the advances proposed by the present guidelines, several challenges preclude the prompt implementation of these diagnostic and therapeutic measures. The present article discusses the challenges for the broad implementation of the sCAP guidelines and proposes solutions when applicable.

Switches in non-invasive respiratory support strategies during acute hypoxemic respiratory failure: Need to monitoring from a retrospective observational study

OBJECTIVE

To explore combined non-invasive-respiratory-support (NIRS) patterns, reasons for NIRS switching, and their potential impact on clinical outcomes in acute-hypoxemic-respiratory-failure (AHRF) patients.

DESIGN

Retrospective, single-center observational study.

SETTING

Intensive Care Medicine.

PATIENTS

AHRF patients (cardiac origin and respiratory acidosis excluded) underwent combined NIRS therapies such as non-invasive-ventilation (NIV) and High-Flow-Nasal-Cannula (HFNC).

INTERVENTIONS

Patients were classified based on the first NIRS switch performed (HFNC-to-NIV or NIV-to-HFNC), and further specific NIRS switching strategies (NIV trial-like vs. Non-NIV trial-like and single vs. multiples switches) were independently evaluated.

MAIN VARIABLES OF INTEREST

Reasons for switching, NIRS failure and mortality rates.

RESULTS

A total of 63 patients with AHRF were included, receiving combined NIRS, 58.7% classified in the HFNC-to-NIV group and 41.3% in the NIV-to-HFNC group. Reason for switching from HFNC to NIV was AHRF worsening (100%), while from NIV to HFNC was respiratory improvement (76.9%). NIRS failure rates were higher in the HFNC-to-NIV than in NIV-to-HFNC group (81% vs. 35%, p < 0.001). Among HFNC-to-NIV patients, there was no difference in the failure rate between the NIV trial-like and non-NIV trial-like groups (86% vs. 78%, p = 0.575) but the mortality rate was significantly lower in NIV trial-like group (14% vs. 52%, p = 0.02). Among NIV to HFNC patients, NIV failure was lower in the single switch group compared to the multiple switches group (15% vs. 53%, p = 0.039), with a shorter length of stay (5 [2-8] vs. 12 [8-30] days, p = 0.001).

CONCLUSIONS

NIRS combination is used in real life and both switches' strategies, HFNC to NIV and NIV to HFNC, are common in AHRF management. Transitioning from HFNC to NIV is suggested as a therapeutic escalation and in this context performance of a NIV-trial could be beneficial. Conversely, switching from NIV to HFNC is suggested as a de-escalation strategy that is deemed safe if there is no NIRS failure.

How I manage acute respiratory failure in patients with hematological malignancies

ABSTRACT

Acute respiratory failure (ARF) is common in patients with hematological malignancies notably those with acute leukemia, myelodysplastic syndrome, or allogeneic stem cell transplantation. ARF is the leading reason for intensive care unit (ICU) admission, with a 35% case fatality rate. Failure to identify the ARF cause is associated with mortality. A prompt, well-designed diagnostic workup is crucial. The investigations are chosen according to pretest diagnostic probabilities, estimated by the DIRECT approach: D stands for delay, or time since diagnosis; I for pattern of immune deficiency; R and T for radiological evaluation; E refers to clinical experience, and C to the clinical picture. Thorough familiarity with rapid diagnostic tests helps to decrease the use of bronchoscopy with bronchoalveolar lavage, which can cause respiratory status deterioration in those patients with hypoxemia. A prompt etiological diagnosis shortens the time on unnecessary empirical treatments, decreasing iatrogenic harm and costs. High-quality collaboration between intensivists and hematologists and all crossdisciplinary health care workers is paramount. All oxygen delivery systems should be considered to minimize invasive mechanical ventilation. Treatment of the malignancy is started or continued in the ICU under the guidance of the hematologists. The goal is to use the ICU as a bridge to recovery, with the patient returning to the hematology ward in sufficiently good clinical condition to receive optimal anticancer treatment.

Critically Ill Patients with Visceral Nocardia Infection, France and Belgium, 2004-2023

We studied 50 patients with invasive nocardiosis treated during 2004-2023 in intensive care centers in France and Belgium. Most (65%) died in the intensive care unit or in the year after admission. Nocardia infections should be included in the differential diagnoses for patients in the intensive care setting.

Continuous positive airway pressure versus high-flow nasal cannula oxygen therapy for acute hypoxemic respiratory failure: A randomized controlled trial

BACKGROUND AND OBJECTIVE

The relative effectiveness of initial non-invasive respiratory strategies for acute respiratory failure using continuous positive airway pressure (CPAP) or high-flow nasal cannula (HFNC) is unclear.

METHODS

We conducted a multicenter, open-label, parallel-group randomized controlled trial to compare the efficacy of CPAP and HFNC on reducing the risk of meeting the prespecified criteria for intubation and improving clinical outcomes of acute hypoxemic respiratory failure. The primary endpoint was the time taken to meet the prespecified criteria for intubation within 28 days.

RESULTS

Eighty-five patients were randomly assigned to the CPAP or HFNC group. Eleven (28.9%) in the CPAP group and twenty (42.6%) in the HFNC group met the criteria for intubation within 28 days. Compared with HFNC, CPAP reduced the risk of meeting the intubation criteria (hazard ratio [HR], 0.327; 95% CI, 0.148-0.724; p = 0.006). There were no significant between-group differences in the intubation rates, in-hospital and 28-day mortality rates, ventilator-free days, duration of the need for respiratory support, or duration of hospitalization for respiratory illness. Pulmonary oxygenation was significantly better in the CPAP group, with significantly lower pH and higher partial pressure of carbon dioxide, but there were no differences in the respiratory rate between groups. CPAP and HFNC were associated with few possibly causal adverse events.

CONCLUSION

CPAP is more effective than HFNC at reducing the risk of meeting the intubation criteria in patients with acute hypoxemic respiratory failure.

High-Flow Nasal Cannula Oxygen Therapy in the Management of Respiratory Failure: A Review

High-flow nasal cannula (HFNC) oxygen therapy is gaining traction globally as a treatment for respiratory failure. There are several physiological benefits, and there is a growing body of evidence showing improved quality of life and patient comfort with HFNC, both in acute and home settings. Due to the increased burden of long-term respiratory conditions such as chronic obstructive pulmonary disease (COPD) on healthcare systems worldwide, the role of ward-based and post-discharge interventions in the prevention of hospital readmissions is an area of increasing interest. In this narrative review, we outline the physiological effects of HFNC and assess its applications in both the hospital and home settings for acute and chronic respiratory failure. We also consider the evidence of non-invasive ventilation (NIV) versus HFNC in the hospital setting and the application of HFNC at home in stable hypercapnic respiratory failure to improve the quality of life and prevent readmissions. We also look at applications of HFNC in specific circumstances, such as the perioperative period, emergency department, and acute (mainly critical care) setting including in immunocompromised patients and palliative care.

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.

High-flow nasal cannula oxygen versus conventional oxygen therapy for acute respiratory failure due to COVID-19: a systematic review and meta-analysis

BACKGROUND

The effectiveness of high-flow nasal cannula oxygen therapy (HFNC) in patients with acute respiratory failure due to COVID-19 remains uncertain. We aimed at assessing whether HFNC is associated with reduced risk of intubation or mortality in patients with acute respiratory failure due to COVID-19 compared with conventional oxygen therapy (COT).

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, Embase, Web of Science, and CENTRAL databases for randomized controlled trials (RCTs) and observational studies comparing HFNC vs. COT in patients with acute respiratory failure due to COVID-19, published in English from inception to December 2022. Pediatric studies, studies that compared HFNC with a noninvasive respiratory support other than COT and those in which intubation or mortality were not reported were excluded. Two authors independently screened and selected articles for inclusion, extracted data, and assessed the risk of bias. Fixed-effects or random-effects meta-analysis were performed according to statistical heterogeneity. Primary outcomes were risk of intubation and mortality across RCTs. Effect estimates were calculated as risk ratios and 95% confidence interval (RR; 95% CI). Observational studies were used for sensitivity analyses.

RESULTS

Twenty studies were analyzed, accounting for 8383 patients, including 6 RCTs (2509 patients) and 14 observational studies (5874 patients). By pooling the 6 RCTs, HFNC compared with COT significantly reduced the risk of intubation (RR 0.89, 95% CI 0.80 to 0.98; p = 0.02) and reduced length of stay in hospital. HFNC did not significantly reduce the risk of mortality (RR 0.93, 95% CI 0.77 to 1.11; p = 0.40).

CONCLUSIONS

In patients with acute respiratory failure due to COVID-19, HFNC reduced the need for intubation and shortened length of stay in hospital without significant decreased risk of mortality. Trial registration The study was registered on the International prospective register of systematic reviews (PROSPERO) at https://www.crd.york.ac.uk/prospero/ with the trial registration number CRD42022340035 (06/20/2022).

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.

Noninvasive Oxygenation Strategies in Adult Patients With Acute Hypoxemic Respiratory Failure: A Systematic Review and Network Meta-Analysis

BACKGROUND

Several recently published randomized controlled trials have evaluated various noninvasive oxygenation strategies for the treatment of acute hypoxemic respiratory failure.

RESEARCH QUESTION

Which available noninvasive oxygen strategies are effective for acute hypoxic respiratory failure?

STUDY DESIGN AND METHODS

A systematic review of Medline, Embase, Cochrane CENTRAL, CINAHL, Web of Science, MedRxiv, and Research Square was conducted from inception to October 1, 2022. A random effects frequentist network meta-analysis was performed, and the results are presented using absolute risk difference per 1,000 patients. The Grading of Recommendations, Assessment, Development and Evaluation framework was used to rate the certainty of the evidence. Mortality, invasive mechanical ventilation, duration of hospitalization and ICU stay, ventilator-free days, and level of comfort are reported.

RESULTS

Thirty-six trials (7,046 patients) were included. It was found that helmet CPAP probably reduces mortality compared with standard oxygen therapy (SOT) (231 fewer deaths per 1,000; 95% CI, 126-273 fewer) (moderate certainty). A high-flow nasal cannula (HFNC) probably reduces the need for invasive mechanical ventilation (103.5 fewer events per 1,000; 95% CI, 40.5-157.5 fewer) (moderate certainty). All noninvasive oxygenation strategies may reduce the duration of hospitalization as compared with SOT (low certainty). Helmet bilevel ventilation (4.84 days fewer; 95% CI, 2.33-7.36 days fewer) and helmet CPAP (1.74 days fewer; 95% CI, 4.49 fewer-1.01 more) may reduce the duration of ICU stay as compared with SOT (both low certainty). SOT may be more comfortable than face mask noninvasive ventilation and no different in comfort compared with an HFNC (both low certainty).

INTERPRETATION

A helmet interface for noninvasive ventilation probably reduces mortality and the risk of mechanical ventilation, as well as the duration of hospital and ICU stay. An HFNC probably reduces the risk of invasive mechanical ventilation and may be as comfortable as SOT. Further research is necessary to understand the role of these interfaces in acute hypoxemic respiratory failure.

Sepsis and acute respiratory failure in patients with cancer: how can we improve care and outcomes even further?

PURPOSE OF REVIEW

Care and outcomes of critically ill patients with cancer have improved over the past decade. This selective review will discuss recent updates in sepsis and acute respiratory failure among patients with cancer, with particular focus on important opportunities to improve outcomes further through attention to phenotyping, predictive analytics, and improved outcome measures.

RECENT FINDINGS

The prevalence of cancer diagnoses in intensive care units (ICUs) is nontrivial and increasing. Sepsis and acute respiratory failure remain the most common critical illness syndromes affecting these patients, although other complications are also frequent. Recent research in oncologic sepsis has described outcome variation - including ICU, hospital, and 28-day mortality - across different types of cancer (e.g., solid vs. hematologic malignancies) and different sepsis definitions (e.g., Sepsis-3 vs. prior definitions). Research in acute respiratory failure in oncology patients has highlighted continued uncertainty in the value of diagnostic bronchoscopy for some patients and in the optimal respiratory support strategy. For both of these syndromes, specific challenges include multifactorial heterogeneity (e.g. in etiology and/or underlying cancer), delayed recognition of clinical deterioration, and complex outcomes measurement.

SUMMARY

Improving outcomes in oncologic critical care requires attention to the heterogeneity of cancer diagnoses, timely recognition and management of critical illness, and defining appropriate ICU outcomes.

Outcomes and time trends of acute respiratory distress syndrome patients with and without liver cirrhosis: an observational cohort

BACKGROUND

In studies prior to lung-protective ventilation, liver cirrhosis in acute respiratory distress syndrome (ARDS) was associated with high mortality rates. Since patients with cirrhosis have been excluded from many trials on ARDS, their outcome when treated with lung-protective ventilation is unclear. The objectives were to assess whether cirrhosis is associated with mortality in ARDS and trends over time in mortality and severity.

METHODS

We conducted a retrospective analysis of a prospective observational cohort conducted in a 20-bed tertiary ICU from October 2003 to December 2021. All consecutive adult critically ill patients with ARDS were included. ARDS was defined by the Berlin criteria. The primary outcome was 90 day mortality, assessed with Kaplan-Meier curves and multivariate Cox analysis. Time trends were assessed on 90 day mortality, Sequential Organ-Function Assessment score (SOFA) and non-hepatic SOFA. Ventilation settings were compared between patients with and without cirrhosis.

RESULTS

Of the 7155 patients screened, 863 had a diagnosis of ARDS. Among these ARDS patients, 157(18%) had cirrhosis. The overall 90 day mortality was of 43% (378/863), 57% (90/157) in patients with cirrhosis and 41% (288/706) in patients without cirrhosis (p < 0.001). On survival curves, cirrhosis was associated with 90 day mortality (p < 0.001). Cirrhosis was independently associated with 90 day mortality in multivariate analysis (hazard ratio = 1.56, 95% confidence interval 1.20-2.02). There was no change in mortality over time in ARDS patients with and without cirrhosis. SOFA (p = 0.04) and non-hepatic SOFA (p = 0.02) increased over time in ARDS patients without cirrhosis, and remained stable in ARDS patients with cirrhosis. Tidal volume, positive end-expiratory pressure, plateau pressure and driving pressure were not different between ARDS patients with and without cirrhosis.

CONCLUSIONS

Although ARDS management improved over the last decades, the 90 day mortality remained high and stable over time for both ARDS patients with (57%) and without cirrhosis (41%). Nevertheless, the severity of patients without cirrhosis has increased over time, while the severity of patients with cirrhosis has remained stable.

Clinical Efficiency of Metagenomic Next-Generation Sequencing in Sputum for Pathogen Detection of Patients with Pneumonia According to Disease Severity and Host Immune Status

Purpose

Severe pneumonia causes the highest mortality rate in immunocompromised patients. This study aimed to investigate the pathogen diagnostic efficacy of metagenomic next-generation sequencing (mNGS) using sputum sample in patients with pneumonia according to patients' disease severity and immune conditions.

Patients and Methods

A total of 180 patients suffering from pneumonia were recruited, and sputum samples were collected in duplicate for pathogen detection by both conventional microbiological tests (CMT) and mNGS. Then, the performance of pathogen identification was examined between two methods, according to disease severity and patients' immune status.

Results

In comparison to CMT, mNGS had higher positivity rates in all patients with pneumonia (85.0% vs 62.2%, P=9.445e-07). The most commonly detected microorganism in sputum of pneumonia patients was Acinetobacter baumannii (42/180, 23.3%) in bacterum level, Candida albicans in fungus level (44/180, 24.4%), and Human herpesvirus 1 (39/180, 27.5%) in virus level. However, for mNGS results, Candida albicans in 34.9% of positive patients, and Human herpesvirus 1 in 7.7% of positive cases were confirmed as pathogens causing pneumonia. Acinetobacter baumannii detected by mNGS in 75% of positive patients was diagnosed as pathogen of pneumonia. The microorganism profile of sputum mNGS differed according to disease severity and immune status of patients. Pneumocystis jirovecii was more likely to infect immunocompromised patients (P=0.002). Pseudomonas aeruginosa (14.8% vs 0.0%, P=0.008) and Human herpesvirus 1 (26.1% vs 5.3%, P=0.004) had higher infection rate in patients with severe pneumonia compared with non-severe cases. mNGS had overwhelming advantages over CMT in detecting a lot of microorganisms including Streptococcus pneumoniae, Enterococcus faecium, Pneumocystis jirovecii, and majority of viruses.

Conclusion

mNGS is a complementary tool of CMT for detecting suspected pathogens for patients with lower respiratory infections. The interpretation of opportunistic pathogens identified by mNGS is challenging, and needs comprehensive consideration of sequencing data and clinical factors.

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.

Lower Versus Higher Oxygenation Targets for Critically Ill Patients: A Systematic Review

Supplemental oxygen is a standard therapeutic intervention for critically ill patients such as patients suffering from cardiac arrest, myocardial ischemia, traumatic brain injury, and stroke. However, the optimal oxygenation targets remain elusive owing to the paucity and inconsistencies in the relevant literature. A comprehensive analysis of the available scientific evidence was performed to establish the relative efficacy of the lower and higher oxygenation targets. A systematic literature search was conducted in PubMed, MEDLINE, and Scopus databases from 2010 to 2023. Further, Google Scholar was also searched. Studies evaluating the efficacy of oxygenation targets and the associated clinical outcomes were included. Studies that included participants with hyperbaric oxygen therapy, chronic respiratory diseases, or extracorporeal life support were excluded. The literature search was performed by two blinded reviewers. A total of 19 studies were included in this systemic review, including 72,176 participants. A total of 14 randomized control trials were included. A total of 12 studies investigated the efficacy of lower and higher oxygenation targets in ICU-admitted patients, and seven were assessed in patients with acute myocardial infarction and stroke. For ICU patients, the evidence was conflicting, with some studies showing the efficacy of conservative oxygen therapy while others reported no difference. Overall, nine studies concluded that lower oxygen targets are favorable. However, most studies (n=4) in stroke and myocardial infarction patients showed no difference in lower or higher oxygenation targets whereas only two supported lower oxygenation targets. Available evidence suggests that lower oxygenation targets result in either improved or equivalent clinical outcomes compared with higher oxygenation targets.

The COVID-19 Driving Force: How It Shaped the Evidence of Non-Invasive Respiratory Support

During the COVID-19 pandemic, the use of non-invasive respiratory support (NIRS) became crucial in treating patients with acute hypoxemic respiratory failure. Despite the fear of viral aerosolization, non-invasive respiratory support has gained attention as a way to alleviate ICU overcrowding and reduce the risks associated with intubation. The COVID-19 pandemic has led to an unprecedented increased demand for research, resulting in numerous publications on observational studies, clinical trials, reviews, and meta-analyses in the past three years. This comprehensive narrative overview describes the physiological rationale, pre-COVID-19 evidence, and results of observational studies and randomized control trials regarding the use of high-flow nasal oxygen, non-invasive mechanical ventilation, and continuous positive airway pressure in adult patients with COVID-19 and associated acute hypoxemic respiratory failure. The review also highlights the significance of guidelines and recommendations provided by international societies and the need for further well-designed research to determine the optimal use of NIRS in treating this population.

Comparison of High-Flow Nasal Cannula with Conventional Oxygen Therapy in Patients with Hypercapnic Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

Purpose

This study aimed to evaluate the clinical outcomes of high-flow nasal cannula (HFNC) compared with conventional oxygen therapy (COT) in patients with hypercapnic chronic obstructive pulmonary disease (COPD), including arterial partial pressure of carbon dioxide (PaCO₂), arterial partial pressure of oxygen (PaO₂), respiratory rate (RR), treatment failure, exacerbation rates, adverse events and comfort evaluation.

Patients and Methods

PubMed, EMBASE and the Cochrane Library were retrieved from inception to September 30, 2022. Eligible trials were randomized controlled trials and crossover studies comparing HFNC and COT in hypercapnic COPD patients. Continuous variables were reported as mean and standard derivation and calculated by weighted mean differences (MD), while dichotomous variables were shown as frequency and proportion and calculated by odds ratio (OR), with the 95% confidence intervals (Cl). Statistical analysis was performed using RevMan 5.4 software.

Results

Eight studies were included, five with acute hypercapnia and three with chronic hypercapnia. In acute hypercapnic COPD, short-term HFNC reduced PaCO₂ (MD -1.55, 95% CI: -2.85 to -0.25, I² = 0%, p <0.05) and treatment failure (OR 0.54, 95% CI: 0.33 to 0.88, I² = 0%, p<0.05), but there were no significant differences in PaO₂ (MD -0.36, 95% CI: -2.23 to 1.52, I² = 45%, p=0.71) and RR (MD -1.07, 95% CI: -2.44 to 0.29, I² = 72%, p=0.12). In chronic hypercapnic COPD, HFNC may reduce COPD exacerbation rates, but there was no advantage in improving PaCO₂ (MD -1.21, 95% CI: -3.81 to 1.39, I² = 0%, p=0.36) and PaO₂ (MD 2.81, 95% CI: -1.39 to 7.02, I² = 0%, p=0.19).

Conclusion

Compared with COT, short-term HFNC reduced PaCO₂ and the need for escalating respiratory support in acute hypercapnic COPD, whereas long-term HFNC reduced COPD exacerbations rates in chronic hypercapnia. HFNC has great potential for treating hypercapnic COPD.

Comparison of the efficacy and comfort of high-flow nasal cannula with different initial flow settings in patients with acute hypoxemic respiratory failure: a systematic review and network meta-analysis

BACKGROUND

High-flow nasal cannula (HFNC) has been proven effective in improving patients with acute hypoxemic respiratory failure (AHRF), but a discussion of its use for initial flow settings still need to be provided. We aimed to compare the effectiveness and comfort evaluation of HFNC with different initial flow settings in patients with AHRF.

METHODS

Studies published by October 10, 2022, were searched exhaustively in PubMed, Embase, Web of Science, Cochrane Library (CENTRAL), and the China National Knowledge Infrastructure (CNKI) database. Network meta-analysis (NMA) was performed with STATA 17.0 and R software (version 4.2.1). A Bayesian framework was applied for this NMA. Comparisons of competing models based on the deviance information criterion (DIC) were used to select the best model for NMA. The primary outcome is the intubation at day 28. Secondary outcomes included short-term and long-term mortality, comfort score, length of ICU or hospital stay, and 24-h PaO₂/FiO₂.

RESULTS

This NMA included 23 randomized controlled trials (RCTs) with 5774 patients. With NIV as the control, the HFNC_high group was significantly associated with lower intubation rates (odds ratio [OR] 0.72 95% credible interval [CrI] 0.56 to 0.93; moderate quality evidence) and short-term mortality (OR 0.81 95% CrI 0.69 to 0.96; moderate quality evidence). Using HFNC_Moderate (Mod) group (mean difference [MD] - 1.98 95% CrI -3.98 to 0.01; very low quality evidence) as a comparator, the HFNC_Low group had a slight advantage in comfort scores but no statistically significant difference. Of all possible interventions, the HFNC_High group had the highest probability of being the best in reducing intubation rates (73.04%), short-term (82.74%) and long-term mortality (67.08%). While surface under the cumulative ranking curve value (SUCRA) indicated that the HFNC_Low group had the highest probability of being the best in terms of comfort scores.

CONCLUSIONS

The high initial flow settings (50-60 L/min) performed better in decreasing the occurrence of intubation and mortality, albeit with poor comfort scores. Treatment of HFNC for AHRF patients ought to be initiated from moderate flow rates (30-40 L/min), and individualized flow settings can make HFNC more sensible in clinical practice.

High-flow nasal cannula reduces intubation rate in patients with COVID-19 with acute respiratory failure: a meta-analysis and systematic review

OBJECTIVE

This study aimed to investigate the effect of high-flow nasal cannula therapy (HFNC) versus conventional oxygen therapy (COT) on intubation rate, 28-day intensive care unit (ICU) mortality, 28-day ventilator-free days (VFDs) and ICU length of stay (ICU LOS) in adult patients with acute respiratory failure (ARF) associated with COVID-19.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Web of Science, Cochrane Library and Embase up to June 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Only randomised controlled trials or cohort studies comparing HFNC with COT in patients with COVID-19 were included up to June 2022. Studies conducted on children or pregnant women, and those not published in English were excluded.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened the titles, abstracts and full texts. Relevant information was extracted and curated in the tables. The Cochrane Collaboration tool and Newcastle-Ottawa Scale were used to assess the quality of randomised controlled trials or cohort studies. Meta-analysis was conducted using RevMan V.5.4 computer software using a random effects model with a 95% CI. Heterogeneity was assessed using Cochran's Q test (χ²) and Higgins I² statistics, with subgroup analyses to account for sources of heterogeneity.

RESULTS

Nine studies involving 3370 (1480 received HFNC) were included. HFNC reduced the intubation rate compared with COT (OR 0.44, 95% CI 0.28 to 0.71, p=0.0007), decreased 28-day ICU mortality (OR 0.54, 95% CI 0.30 to 0.97, p=0.04) and improved 28-day VFDs (mean difference (MD) 2.58, 95% CI 1.70 to 3.45, p<0.00001). However, HFNC had no effect on ICU LOS versus COT (MD 0.52, 95% CI -1.01 to 2.06, p=0.50).

CONCLUSIONS

Our study indicates that HFNC may reduce intubation rate and 28-day ICU mortality, and improve 28-day VFDs in patients with ARF due to COVID-19 compared with COT. Large-scale randomised controlled trials are necessary to validate our findings.

PROSPERO REGISTRATION NUMBER

CRD42022345713.

Update on the management of acute respiratory failure using non-invasive ventilation and pulse oximetry

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2023. Other selected articles can be found online at  https://www.biomedcentral.com/collections/annualupdate2023 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from  https://link.springer.com/bookseries/8901 .

[Invasive mechanical ventilation in patients with solid tumor or hematological malignancy]

Invasive mechanical ventilation in onco-hematology patients has become relatively routine, and is now part and parcel of their care pathway. Nevertheless, specific complications and subsequent therapeutic possibilities require discussion. To a greater extent than with regard to other patient populations, cooperation between specialist and ICU physician is mandatory, the objective being to more comprehensively assess a therapeutic project before or during the period of invasive mechanical ventilation. After an overview of recent results concerning ventilated patients in intensive care, this review aims to describe the specific complications and factors associated with mortality in this population.

High-value care for critically ill oncohematological patients: what do we know thus far?

The number of patients with cancer requiring intensive care unit admission is increasing around the world. The improvement in the pathophysiological understanding of this group of patients, as well as the increasingly better and more targeted treatment options for their underlying disease, has led to a significant increase in their survival over the past three decades. Within the organizational concepts, it is necessary to know what adds value in the care of critical oncohematological patients. Practices in medicine that do not benefit patients and possibly cause harm are called low-value practices, while high-value practices are defined as high-quality care at relatively low cost. In this article, we discuss ten domains with high-value evidence in the care of cancer patients: (1) intensive care unit admission policies; (2) intensive care unit organization; (3) etiological investigation of hypoxemia; (4) management of acute respiratory failure; (5) management of febrile neutropenia; (6) urgent chemotherapy treatment in critically ill patients; (7) patient and family experience; (8) palliative care; (9) care of intensive care unit staff; and (10) long-term impact of critical disease on the cancer population. The disclosure of such policies is expected to have the potential to change health care standards. We understand that it is a lengthy process, and initiatives such as this paper are one of the first steps in raising awareness and beginning a discussion about high-value care in various health scenarios.

High-Flow Nasal Cannula Oxygen Therapy versus Non-Invasive Ventilation in AIDS Patients with Acute Respiratory Failure: A Randomized Controlled Trial

BACKGROUND

Acute respiratory failure (ARF) remains the most common diagnosis for intensive care unit (ICU) admission in acquired immunodeficiency syndrome (AIDS) patients.

METHODS

We conducted a single-center, prospective, open-labeled, randomized controlled trial at the ICU, Beijing Ditan Hospital, China. AIDS patients with ARF were enrolled and randomly assigned in a 1:1 ratio to receive either high-flow nasal cannula (HFNC) oxygen therapy or non-invasive ventilation (NIV) immediately after randomization. The primary outcome was the need for endotracheal intubation on day 28.

RESULTS

120 AIDS patients were enrolled and 56 patients in the HFNC group and 57 patients in the NIV group after secondary exclusion. Pneumocystis pneumonia (PCP) was the main etiology for ARF (94.7%). The intubation rates on day 28 were similar to HFNC and NIV (28.6% vs. 35.1%, p = 0.457). Kaplan-Meier curves showed no statistical difference in cumulative intubation rates between the two groups (log-rank test 0.401, p = 0.527). The number of airway care interventions in the HFNC group was fewer than in the NIV group (6 (5-7) vs. 8 (6-9), p < 0.001). The rate of intolerance in the HFNC group was lower than in the NIV group (1.8% vs. 14.0%, p = 0.032). The VAS scores of device discomfort in the HFNC group were lower than that in the NIV group at 2 h (4 (4-5) vs. 5 (4-7), p = 0.042) and at 24 h (4 (3-4) vs. 4 (3-6), p = 0.036). The respiratory rate in the HFNC group was lower than that in the NIV group at 24 h (25 ± 4/min vs. 27 ± 5/min, p = 0.041).

CONCLUSIONS

Among AIDS patients with ARF, there was no statistical significance of the intubation rate between HFNC and NIV. HFNC had better tolerance and device comfort, fewer airway care interventions, and a lower respiratory rate than NIV.

CLINICAL TRIAL NUMBER

Chictr.org (ChiCTR1900022241).

Scope of treatment and clinical-decision making in the older patient with COVID-19 infection, a European perspective

PURPOSE

Older patients were particularly vulnerable to severe COVID-19 disease resulting in high in-hospital mortality rates during the two first waves. The aims of this study were to better characterize the management of older people presenting with COVID-19 in European hospitals and to identify national guidelines on hospital admission and ICU admission for this population.

METHODS

Online survey based on a vignette of a frail older patient with Covid-19 distributed by e-mail to all members of the European Geriatric Medicine Society. The survey contained questions regarding the treatment of the vignette patient as well as general questions regarding available services. Additionally, questions on national policies and differences between the first and second wave of the pandemic were asked.

RESULTS

Survey of 282 respondents from 28 different countries was analyzed. Responses on treatment of the patient in the vignette were similar from respondents across the 28 countries. 247 respondents (87%) would admit the patient to the hospital, in most cases to a geriatric COVID-19 ward (78%). Cardiopulmonary resuscitation was found medically inappropriate by 85% of respondents, intubation and mechanical ventilation by 91% of respondents, admission to the ICU by 82%, and ExtraCorpular Membrane Oxygenation (ECMO) by 93%. Sixty percent of respondents indicated they would consult with a palliative care specialist, 56% would seek the help of a spiritual counsellor. National guidelines on admission criteria of geriatric patients to the hospital existed in 22 different European countries.

CONCLUSION

This pandemic has fostered the collaboration between geriatricians and palliative care specialists to improve the care for older patients with a severe disease and often an uncertain prognosis.

High-flow nasal cannula oxygen therapy in acute hypoxemic respiratory failure and COVID-19-related respiratory failure

Although standard oxygen face masks are first-line therapy for patients with acute hypoxemic respiratory failure, high-flow nasal cannula oxygen therapy has gained major popularity in intensive care units. The physiological effects of high-flow oxygen counterbalance the physiological consequences of acute hypoxemic respiratory failure by lessening the deleterious effects of intense and prolonged inspiratory efforts generated by patients. Its simplicity of application for physicians and nurses and its comfort for patients are other arguments for its use in this setting. Although clinical studies have reported a decreased risk of intubation with high-flow oxygen compared with standard oxygen, its survival benefit is uncertain. A more precise definition of acute hypoxemic respiratory failure, including a classification of severity based on oxygenation levels, is needed to better compare the efficiencies of different non-invasive oxygenation support methods (standard oxygen, high-flow oxygen, and non-invasive ventilation). Additionally, the respective role of each non-invasive oxygenation support method needs to be established through further clinical trials in acute hypoxemic respiratory failure, especially in severe forms.

Oxygen saturation targets for adults with acute hypoxemia in low and lower-middle income countries: a scoping review with analysis of contextual factors

Knowing the target oxygen saturation (SpO₂) range that results in the best outcomes for acutely hypoxemic adults is important for clinical care, training, and research in low-income and lower-middle income countries (collectively LMICs). The evidence we have for SpO₂ targets emanates from high-income countries (HICs), and therefore may miss important contextual factors for LMIC settings. Furthermore, the evidence from HICs is mixed, amplifying the importance of specific circumstances. For this literature review and analysis, we considered SpO₂ targets used in previous trials, international and national society guidelines, and direct trial evidence comparing outcomes using different SpO₂ ranges (all from HICs). We also considered contextual factors, including emerging data on pulse oximetry performance in different skin pigmentation ranges, the risk of depleting oxygen resources in LMIC settings, the lack of access to arterial blood gases that necessitates consideration of the subpopulation of hypoxemic patients who are also hypercapnic, and the impact of altitude on median SpO₂ values. This process of integrating prior study protocols, society guidelines, available evidence, and contextual factors is potentially useful for the development of other clinical guidelines for LMIC settings. We suggest that a goal SpO₂ range of 90-94% is reasonable, using high-performing pulse oximeters. Answering context-specific research questions, such as an optimal SpO₂ target range in LMIC contexts, is critical for advancing equity in clinical outcomes globally.

Early intubation and patient-centered outcomes in septic shock: a secondary analysis of a prospective multicenter study

Purpose

Despite the benefits of mechanical ventilation, its use in critically ill patients is associated with complications and had led to the growth of noninvasive techniques. We assessed the effect of early intubation (first 8 h after vasopressor start) in septic shock patients, as compared to non-early intubated subjects (unexposed), regarding in-hospital mortality, intensive care and hospital length of stay.

Methods

This study involves secondary analysis of a multicenter prospective study. To adjust for baseline differences in potential confounders, propensity score matching was carried out. In-hospital mortality was analyzed in a time-to-event fashion, while length of stay was assessed as a median difference using bootstrapping.

Results

A total of 735 patients (137 intubated in the first 8 h) were evaluated. Propensity score matching identified 78 pairs with similar severity and characteristics on admission. Intubation was used in all patients in the early intubation group and in 27 (35%) subjects beyond 8 h in the unexposed group. Mortality occurred in 35 (45%) and in 26 (33%) subjects in the early intubation and unexposed groups (hazard ratio 1.44 95% CI 0.86–2.39, p = 0.16). ICU and hospital length of stay were not different among groups [9 vs. 5 (95% CI 1 to 7) and 14 vs. 16 (95% CI − 7 to 8) days]. All sensitivity analyses confirmed the robustness of our findings.

Conclusions

An early approach to invasive mechanical ventilation did not improve outcomes in this matched cohort of patients. The limited number of patients included in these analyses out the total number included in the study may limit generalizability of these findings.

Trial registration NCT02780466. Registered on May 19, 2016.

High-flow nasal oxygen in acute hypoxemic respiratory failure: A narrative review of the evidence before and after the COVID-19 pandemic

High-flow nasal oxygen (HFNO) is a type of non-invasive advanced respiratory support that allows the delivery of high-flow and humidified air through a nasal cannula. It can deliver a higher inspired oxygen fraction than conventional oxygen therapy (COT), improves secretion clearance, has a small positive end-expiratory pressure, and exhibits a washout effect on the upper air space that diminishes dead space ventilation. HFNO has been shown to reduce the work of breathing in acute hypoxemic respiratory failure (AHRF) and has become an interesting option for non-invasive respiratory support. Evidence published before the COVID-19 pandemic suggested a possible reduction of the need for invasive mechanical ventilation compared to COT. The COVID-19 pandemic has resulted in a substantial increase in AHRF worldwide, overwhelming both acute and intensive care unit capacity in most countries. This triggered new trials, adding to the body of evidence on HFNO in AHRF and its possible benefits compared to COT or non-invasive ventilation. We have summarized and discussed this recent evidence to inform the best supportive strategy in AHRF both related and unrelated to COVID-19.

The short-term efficacy of high flow nasal oxygen therapy on cardiovascular surgical patients: a randomized crossover trial

Background

Oxygen therapy after extubation in the intensive care unit (ICU) is essential in order to maintain adequate oxygenation, especially in patients who have undertaken cardiovascular surgery. A Venturi mask (VM) has been routinely used as an oxygen therapy in the ICU. Recently, however, the high flow nasal cannula (HFNC) has become available, and this device can deliver up to 60 L/min of humidified oxygen. The aim of this study is to evaluate the short-term efficacy between HFNC and VM in cardiovascular surgical patients.

Methods

Forty patients who underwent cardiovascular surgery were randomized to either protocol A (HFNC followed by VM) or protocol B (VM followed by HFNC). After 60-minutes of use with either device, arterial blood gas analysis was performed, and the PaO₂/FiO₂ ratio (PFR) was calculated. Simultaneously, physiological data (respiratory rate, heart rate, mean arterial pressure, continuous cardiac index, and mixed venous oxygen saturation) were recorded. During this procedure, FiO₂ and gas flow were maintained at a fixed rate. These variables were compared by using the paired t-test, and a p value < 0.05 was considered significant. All data were expressed as mean (standard deviation).

Results

Thirty-five patients (17 from protocol A and 18 from protocol B) were enrolled, and 5 patients were excluded from analysis in accordance with the exit criteria. PaO₂ was significantly higher in the HFNC group than in the VM group [101.7 (25.9) vs. 91.8 (23.0), mean difference 9.87 (18.5), 95% confidence interval 3.5 to 16.2, p = 0.003]. Moreover, PFR was significantly higher in the HFNC group than in the VM group [265.9 (81.4) vs. 238.7 (68.5), p = 0.002]. Moreover, PaCO₂ was significantly lower in the HFNC group than in the VM group [33.8 (3.5) vs. 34.7 (2.9), p = 0.033]. The respiratory rate was significantly lower in the HFNC group than in the VM group [18 (4) vs. 21 (4), p = 0.006], and no significant differences were seen in any of the other parameters.

Conclusions

Compared to VM, HFNC ameliorated oxygenation function and decreased patients’ effort in breathing. The hemodynamic state did not differ between HFNC and VM. Therefore, HFNC can be used safely in cardiovascular surgical patients.

Trial registration

This trial was registered with the UMIN Clinical Trials Registry (ID UMIN000016572).

Recent advances in the use of high flow nasal oxygen therapies

High flow nasal oxygen is a relatively new option for treating patients with respiratory failure, which decreases work of breathing, improves tidal volume, and modestly increases positive end expiratory pressure. Despite well-described physiologic benefits, the clinical impact of high flow nasal oxygen is still under investigation. In this article, we review the most recent findings on the clinical efficacy of high flow nasal oxygen in Type I, II, III, and IV respiratory failure within adult and pediatric patients. Additionally, we discuss studies across clinical settings, including emergency departments, intensive care units, outpatient, and procedural settings.

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.

Metagenomic next-generation sequencing-guided antimicrobial treatment versus conventional antimicrobial treatment in early severe community-acquired pneumonia among immunocompromised patients (MATESHIP): A study protocol

Background

Severe community-acquired pneumonia (SCAP) is the main cause of mortality in immunocompromised patients. Compared with conventional microbiological tests (CMT), metagenomic next-generation sequencing (mNGS) can quickly and simultaneously detect a wide array of bacteria, viruses, and fungi in an unbiased manner. It is increasingly used for severe respiratory infectious diseases, especially for immunocompromised patients. However, the effects of mNGS-based antimicrobial treatment procedures on clinical outcomes in immunocompromised patients with SCAP have not been evaluated.

Methods/Design

The MATESHIP study is a prospective, multicenter, parallel-group, open-label, randomized controlled trial from 20 ICUs in university hospitals and academic teaching hospitals across Shandong Province, China. We will enroll 342 immunocompromised patients with early onset SCAP who are admitted to an intensive care unit (ICU). Participants will be randomly allocated to an mNGS-guided treatment group or a conventional treatment group (guided by CMT), according to centrally computer-based block randomization stratified by participating centers. Participants will undergo CMT tests using appropriate lower respiratory tract (LRT) and other necessary specimens, with or without mNGS tests using LRT specimens. The primary outcomes will be: (1) The relative change in Sequential Organ Failure Assessment (SOFA) score from randomization to day 5, day 7, day 10, or the day of ICU discharge/death; and (2) the consumption of antimicrobial agents during ICU stay (expressed as defined daily doses). The secondary outcome measures will be: days from randomization to initiation of definitive antimicrobial treatment; overall antimicrobial agent use and cost; total cost of hospitalization; length of ICU stay; 28- and 90-day mortality; and clinical cure rate. This study hypothesizes that mNGS-guided treatment will decrease the degree of organ dysfunction/failure, the consumption of antimicrobial agents, and mortality, while the cure rate will be increased, and the time to initiation of appropriate therapy will be advanced.

Discussion

The MATESHIP study will evaluate for the first time whether mNGS-guided antimicrobial therapy improves the outcomes of SCAP in an immunocompromised population, and provide high-level evidence on the application of mNGS in the management of this population.

Clinical Trial Registration

[ClinicalTrials.gov], identifier [NCT05290454].

ARDS Clinical Practice Guideline 2021

BACKGROUND

The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021.

METHODS

The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method.

RESULTS

Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4-8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO2 (PaO2) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D), we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D), we suggest against routinely implementing NO inhalation therapy (GRADE 2C), and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D).

CONCLUSIONS

This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jsicm.org/publication/guideline.html ). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.