Guidelines on the management of acute respiratory distress syndrome

ICU tracheotomies in patients with COVID-19: a lesson learned for future viral pandemic

INTRODUCTION

The coronavirus SARS-CoV-2 pandemic has resulted in a large number of patients requiring intubation and prolonged mechanical ventilation. The current knowledge on the tracheotomies regarding the time form intubation, method and ventilatory parameters optimal for their performance in the mechanically ventilated patients with COVID ARDS are scarce; thus, the aim of this study is to present new data regarding their safety, adverse events and timing.

MATERIALS AND METHODS

This retrospective observational study is based on the data of 66 critically ill COVID patients including demographic data, timing and technique of tracheotomy, ventilatory parameters in the time of procedure, as well as complication and survival rate.

RESULTS

A number of 66 patients with COVID-related pneumonia were included in the study, among whom 32 were tracheotomized-25 patients underwent an early tracheotomy and 7 patients had late tracheotomy. The median duration of mechanical ventilation before the tracheotomy in the early group was 8 days (IQR 6-10) compared to 11 days (IQR 11-12.5.) p < 0.001) in late group. Risk of death in tracheotomy patients was significantly growing with growing level of PEEP and FiO2 at the moment of decision on tracheotomy, OR = 1.91 CI₉₅ (1.23;3.57); p = 0.014 and OR = 1.18 CI₉₅(1.03;1.43); p = 0.048, respectively.

CONCLUSION

Early percutaneous tracheotomy is safe (both in terms of risk of viral transmission and complication rate) and feasible in COVID-19 patients. Stability of gas exchange, and ventilatory parameters are the main prognostic factors of the outcome.

Should oral chlorhexidine remain in ventilator-associated pneumonia prevention bundles?

Ventilator-associated pneumonia (VAP) is related with high mortality, duration of mechanical ventilation and costs. Recent studies have questioned the safety and effectiveness of oral chlorhexidine to prevent VAP. We sought to verify whether the adverse effects of this substance outweigh its benefits. We searched several databases and selected studies that investigated the use of oral chlorhexidine and its impact on mortality. No association between oral chlorhexidine and lower VAP rates was found on meta-analyses of double-blind randomized trials, however significant increase in mortality was reported. It is speculated that chlorhexidine can cause damage to several organic sectors and cytotoxicity. Although it still can be beneficial in specific settings, robust evidence to recommend its routine application for all mechanically ventilated patients is lacking; therefore, given the possibility of harm, it would be better to follow the principle of non-maleficence until more studies becomes available.

Protocolized Post-Cardiac Arrest Care with Targeted Temperature Management

Improvements in teamwork and resuscitation science have considerably increased the success rate of cardiopulmonary resuscitation. Cerebral injury, myocardial dysfunction, systemic ischemia and reperfusion response, and precipitating pathology after the return of spontaneous circulation (ROSC) constitute post-cardiac arrest syndrome. Because the entire body is involved in cardiac arrest and the early post-arrest period, protocolized post-arrest care consisting of cardiovascular optimization, ventilation and oxygenation adjustment, coronary revascularization, targeted temperature management (TTM), and control of seizures and blood sugar would benefit survival and neurological outcomes. Emergent coronary angiography is suggested for cardiac arrest survivors suspected of having ST-elevation myocardial infarction, however the superiority of culprit or complete revascularization in patients with multivessel coronary lesions remains undetermined. High-quality TTM should be considered for comatose patients who are successfully resuscitated from cardiac arrest, however the optimal target temperature may depend on the severity of their condition. The optimal timing for making prognostication should be no earlier than 72 h after rewarming in TTM patients, and 72 h following ROSC in non-TTM patients. To predict neurological recovery correctly may need the use of several prognostic tools together, including clinical neurological examinations, brain images, neurological studies and biomarkers.

Mechanical Ventilation for COVID-19 Patients

Non-invasive ventilation (NIV) or invasive mechanical ventilation (MV) is frequently needed in patients with acute hypoxemic respiratory failure due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. While NIV can be delivered in hospital wards and nonintensive care environments, intubated patients require intensive care unit (ICU) admission and support. Thus, the lack of ICU beds generated by the pandemic has often forced the use of NIV in severely hypoxemic patients treated outside the ICU. In this context, awake prone positioning has been widely adopted to ameliorate oxygenation during noninvasive respiratory support. Still, the incidence of NIV failure and the role of patient self-induced lung injury on hospital outcomes of COVID-19 subjects need to be elucidated. On the other hand, endotracheal intubation is indicated when gas exchange deterioration, muscular exhaustion, and/or neurological impairment ensue. Yet, the best timing for intubation in COVID-19 is still widely debated, as it is the safest use of neuromuscular blocking agents. Not differently from other types of acute respiratory distress syndrome, the aim of MV during COVID-19 is to provide adequate gas exchange while avoiding ventilator-induced lung injury. At the same time, the use of rescue therapies is advocated when standard care is unable to guarantee sufficient organ support. Nevertheless, the general shortage of health care resources experienced during SARS-CoV-2 pandemic might affect the utilization of high-cost, highly specialized, and long-term supports. In this article, we describe the state-of-the-art of NIV and MV setting and their usage for acute hypoxemic respiratory failure of COVID-19 patients.

Incidence, clinical characteristics and outcome of barotrauma in critically ill patients with COVID-19: a systematic review and meta-analysis

INTRODUCTION

Barotrauma is rare in patients with acute respiratory distress syndrome undergoing mechanical ventilation. Its incidence seems increased among critically ill COVID-19 patients. We performed a systematic review and meta-analysis to investigate the incidence, risk factors and clinical outcomes of barotrauma among critically ill COVID-19 patients EVIDENCE ACQUISITION: PubMed was searched from March 1st, 2020 to August 31st, 2021; case series and retrospective cohort studies concerning barotrauma in adult critically ill COVID-19 patients, either hospitalized in the Intensive Care Unit (ICU) or invasively ventilated were included. Primary outcome was the incidence of barotrauma in COVID-19 versus non-COVID-19 patients. Secondary outcomes were clinical characteristics, ventilator parameters, mortality and length of stay between patients with and without barotrauma.

EVIDENCE SYNTHESIS

We identified 21 studies (six case series, 15 retrospective cohorts). The overall incidence of barotrauma was 11 [95% CI: 8-14]% in critically ill COVID-19 patients, vs. 2 [1-3]% in non-COVID-19, P<0.001; the incidence in mechanically ventilated patients was 14 [11-17]% vs. 4 [2-5]% non-COVID-19 patients, P<0.001. There were no differences in demographic, clinical, ventilatory parameters between patients who did and did not develop barotrauma, while, on average, protective ventilation criteria were always respected. Among COVID-19 patients, those with barotrauma had a higher mortality (60 [55-66] vs. 48 [42-54]%, P<0.001) and a longer ICU length of stay (20 [14-26] vs. 13 [10,5-16] days, P=0.03).

CONCLUSIONS

Barotrauma is a frequent complication in critically ill COVID-19 patients and is associated with a poor prognosis. Since lung protective ventilation was delivered, the ventilatory management might not be the sole factor in the development of barotrauma.

Pressure Injury Development, Mitigation, and Outcomes of Patients Proned for Acute Respiratory Distress Syndrome

OBJECTIVE

To describe trends and risk factors for pressure injuries (PIs) in adult critical care patients proned to alleviate acute respiratory distress syndrome secondary to COVID-19 and examine the effectiveness of products and strategies used to mitigate PIs.

METHODS

The authors conducted a retrospective chart review between April 9 and June 8, 2020. Demographic data were analyzed using descriptive statistics. Differences between groups with and without PIs were analyzed.

RESULTS

Among 147 patients, significant PI risk factors included male sex (P = .019), high body mass index (>40 kg/m2; P = .020), low Braden Scale score (<12; P = .018), and low-dose vasopressor therapy (P = .020). Taping endotracheal tubes (ETTs) caused significantly fewer facial PIs than commercial ETT holders (P < .0001). Maximum prone duration/session was a significant risk factor for anterior PIs (P = .016), which dropped 71% with newer pressure redistribution products. d-Dimer greater than 3,200 μg/mL (P = .042) was a significant risk factor for sacrococcygeal PIs while supine. Mortality was 30%; significant risk factors included age older than 60 years (P = .005), Sequential Organ Failure Assessment score greater than 11 (P = .003), and comorbid congestive heart failure (P = .016).

CONCLUSIONS

Taping the ETT, limiting the maximum duration of prone positioning to less than 32 hours, and frequent repositioning while supine may reduce the number of modifiable risk factors for PIs. Standardized methods for testing products for PI prevention will inform individualized patient care.

Nitric oxide: Clinical applications in critically ill patients

Inhaled nitric oxide (iNO) acts as a selective pulmonary vasodilator and it is currently approved by the FDA for the treatment of persistent pulmonary hypertension of the newborn. iNO has been demonstrated to effectively decrease pulmonary artery pressure and improve oxygenation, while decreasing extracorporeal life support use in hypoxic newborns affected by persistent pulmonary hypertension. Also, iNO seems a safe treatment with limited side effects. Despite the promising beneficial effects of NO in the preclinical literature, there is still a lack of high quality evidence for the use of iNO in clinical settings. A variety of clinical applications have been suggested in and out of the critical care environment, aiming to use iNO in respiratory failure and pulmonary hypertension of adults or as a preventative measure of hemolysis-induced vasoconstriction, ischemia/reperfusion injury and as a potential treatment of renal failure associated with cardiopulmonary bypass. In this narrative review we aim to present a comprehensive summary of the potential use of iNO in several clinical conditions with its suggested benefits, including its recent application in the scenario of the COVID-19 pandemic. Randomized controlled trials, meta-analyses, guidelines, observational studies and case-series were reported and the main findings summarized. Furthermore, we will describe the toxicity profile of NO and discuss an innovative proposed strategy to produce iNO. Overall, iNO exhibits a wide range of potential clinical benefits, that certainly warrants further efforts with randomized clinical trials to determine specific therapeutic roles of iNO.

2021 Acute Respiratory Distress Syndrome Update, With Coronavirus Disease 2019 Focus

Acute respiratory distress syndrome (ARDS) is a heterogeneous lung disease responsible for significant morbidity and mortality among critically ill patients, including those infected with severe acute respiratory syndrome coronavirus 2, the virus responsible for coronavirus disease 2019. Despite recent advances in pathophysiology, diagnostics, and therapeutics, ARDS is dangerously underdiagnosed, and supportive lung protective ventilation and prone positioning remain the mainstay interventions. Rescue therapies, including neuromuscular blockade and venovenous extracorporeal membrane oxygenation, remain a key component of clinical practice, although benefits are unclear. Even though coronavirus disease 2019 ARDS has some distinguishing features from traditional ARDS, including delayed onset, hyperinflammatory response, and pulmonary microthrombi, it clinically is similar to traditional ARDS and should be treated with established supportive therapies.

Sex Differences in Use of Low Tidal Volume Ventilation in COVID-19-Insights From the PRoVENT-COVID Study

The purpose of this study was to compare and understand differences in the use of low tidal volume ventilation (LTVV) between females and males with acute respiratory distress syndrome (ARDS) related to coronavirus disease 2019 (COVID-19). This is a post-hoc analysis of an observational study in invasively ventilated patients with ARDS related to COVID-19 in 22 ICUs in the Netherlands. The primary endpoint was the use of LTVV, defined as having received a median tidal volume (V_T) ≤6 ml/kg predicted body weight (PBW) during controlled ventilation. A mediation analysis was used to investigate the impact of anthropometric factors, next to the impact of sex per se. The analysis included 934 patients, 251 females and 683 males. All the patients had ARDS, and there were no differences in ARDS severity between the sexes. On the first day of ventilation, females received ventilation with a higher median V_T compared with males [6.8 (interquartile range (IQR) 6.0–7.6 vs. 6.3 (IQR 5.8–6.9) ml/kg PBW; p < 0.001]. Consequently, females received LTVV less often than males (23 vs. 34%; p = 0.003). The difference in the use of LTVV became smaller but persisted over the next days (27 vs. 36%; p = 0.046 at day 2 and 28 vs. 38%; p = 0.030 at day 3). The difference in the use LTVV was significantly mediated by sex per se [average direct effect of the female sex, 7.5% (95% CI, 1.7–13.3%); p = 0.011] and by differences in the body height [average causal mediation effect, −17.5% (−21.5 to −13.5%); p < 0.001], but not by the differences in actual body weight [average causal mediation effect, 0.2% (−0.8 to 1.2%); p = 0.715]. In conclusion, in this cohort of patients with ARDS related to COVID-19, females received LTVV less often than males in the first days of invasive ventilation. The difference in the use of LTVV was mainly driven by an anthropometric factor, namely, body height. Use of LTVV may improve by paying attention to correct titration of V_T, which should be based on PBW, which is a function of body height.

Body position for preventing ventilator-associated pneumonia for critically ill patients: a systematic review and network meta-analysis

Background

The evidence about the best body position to prevent ventilator-associated pneumonia (VAP) is unclear. The aim of this study was to know what the best body position is to prevent VAP, shorten the length of intensive care unit (ICU) and hospital stay, and reduce mortality among patients undergoing mechanical ventilation (MV).

Methods

We performed a network meta-analysis of randomized controlled trials including intubated patients undergoing MV and admitted to an ICU. The assessed interventions were different body positions (i.e., lateral, prone, semi-recumbent) or alternative degrees of positioning in mechanically ventilated patients.

Results

Semi-recumbent and prone positions showed a risk reduction of VAP incidence (RR: 0.38, 95% CI: 0.25–0.52) and mortality (RR: 0.70, 95% CI: 0.50–0.91), respectively, compared to the supine position. The ranking probabilities and the surface under the cumulative ranking displayed as the first best option of treatment the semi-recumbent position to reduce the incidence of VAP (71.4%), the hospital length of stay (68.9%), and the duration of MV (67.6%); and the prone position to decrease the mortality (89.3%) and to reduce the ICU length of stay (59.3%).

Conclusions

Cautiously, semi-recumbent seems to be the best position to reduce VAP incidence, hospital length of stay and the duration of MV. Prone is the most effective position to reduce the risk of mortality and the ICU length of stay, but it showed no effect on the VAP incidence.

Registration PROSPERO CRD42021247547

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-022-00600-z.

CytoSorb Rescue for COVID-19 Patients With Vasoplegic Shock and Multiple Organ Failure: A Prospective, Open-Label, Randomized Controlled Pilot Study

To investigate the effect of extracorporeal cytokine reduction by CytoSorb (CytoSorbents, Monmouth Junction, NJ) on COVID-19–associated vasoplegic shock.

Association of ventilator type with hospital mortality in critically ill patients with SARS-CoV2 infection: a prospective study

Background

To evaluate the association between ventilator type and hospital mortality in patients with acute respiratory distress syndrome (ARDS) related to COVID-19 (SARS-CoV2 infection), a single-center prospective observational study in France.

Results

We prospectively included consecutive adults admitted to the intensive care unit (ICU) of a university-affiliated tertiary hospital for ARDS related to proven COVID-19, between March 2020 and July 2021. All patients were intubated. We compared two patient groups defined by whether an ICU ventilator or a less sophisticated ventilator such as a sophisticated turbine-based transport ventilator was used. Kaplan–Meier survival curves were plotted. Cox multivariate regression was performed to identify associations between patient characteristics and hospital mortality. We included 189 patients (140 [74.1%] men) with a median age of 65 years [IQR, 55–73], of whom 61 (32.3%) died before hospital discharge. By multivariate analysis, factors associated with in-hospital mortality were age ≥ 70 years (HR, 2.11; 95% CI, 1.24–3.59; P = 0.006), immunodeficiency (HR, 2.43; 95% CI, 1.16–5.09; P = 0.02) and serum creatinine ≥ 100 µmol/L (HR, 3.01; 95% CI, 1.77–5.10; P < 0.001) but not ventilator type. As compared to conventional ICU (equipped with ICU and anesthesiology ventilators), management in transient ICU (equipped with non-ICU turbine-based ventilators) was associated neither with a longer duration of invasive mechanical ventilation (18 [IQR, 11–32] vs. 21 [13–37] days, respectively; P = 0.39) nor with a longer ICU stay (24 [IQR, 14–40] vs. 27 [15–44] days, respectively; P = 0.44).

Conclusions

In ventilated patients with ARDS due to COVID-19, management in transient ICU equipped with non-ICU sophisticated turbine-based ventilators was not associated with worse outcomes compared to standard ICU, equipped with ICU ventilators. Although our study design is not powered to demonstrate any difference in outcome, our results after adjustment do not suggest any signal of harm when using these transport type ventilators as an alternative to ICU ventilators during COVID-19 surge.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-00981-2.

Assessment of respiratory support decision and the outcome of invasive mechanical ventilation in severe COVID-19 with ARDS

Background

The coronavirus disease 2019 (COVID-19) is an ongoing pandemic. Invasive mechanical ventilation (IMV) is essential for the management of COVID-19 with acute respiratory distress syndrome (ARDS). We aimed to assess the impact of compliance with a respiratory decision support system on the outcomes of patients with COVID-19-associated ARDS who required IMV.

Methods

In this retrospective, single-center, case series study, patients with COVID-19-associated ARDS who required IMV at Zhongnan Hospital of Wuhan University, China, from January 8th, 2020, to March 24th, 2020, with the final follow-up date of April 20th, 2020, were included. Demographic, clinical, laboratory, imaging, and management information were collected and analyzed. Compliance with the respiratory support decision system was documented, and its relationship with 28-day mortality was evaluated.

Results

The study included 46 COVID-19-associated ARDS patients who required IMV. The median age of the 46 patients was 68.5 years, and 31 were men. The partial pressure of arterial oxygen (PaO₂)/fraction of inspired oxygen (FiO₂) ratio at intensive care unit (ICU) admission was 104 mmHg. The median total length of IMV was 12.0 (interquartile range [IQR]: 6.0-27.3) days, and the median respiratory support decision score was 11.0 (IQR: 7.8-16.0). To 28 days after ICU admission, 18 (39.1%) patients died. Survivors had a significantly higher respiratory support decision score than non-survivors (15.0 [10.3-17.0] vs. 8.5 (6.0-10.3), P = 0.001). Using receiver operating characteristic (ROC) curve to assess the discrimination of respiratory support decision score to 28-day mortality, the area under the curve (AUC) was 0.796 (95% confidence interval [CI]: 0.657-0.934, P = 0.001) and the cut-off was 11.5 (sensitivity = 0.679, specificity = 0.889). Patients with a higher score (>11.5) were more likely to survive at 28 days after ICU admission (log-rank test, P < 0.001).

Conclusions

For severe COVID-19-associated ARDS with IMV, following the respiratory support decision and assessing completion would improve the progress of ventilation. With a decision score of >11.5, the mortality at 28 days after ICU admission showed an obvious decrease.

The COVID-19 Patient in the Surgical Intensive Care Unit

COVID-19 continues to rampage around the world. Noncritical care-trained physicians may be deployed into the intensive care unit to manage these complex patients. Although COVID-19 is primarily a respiratory disease, it is also associated with significant pathology in the brain, heart, vasculature, lungs, gastrointestinal tract, and kidneys. This article provides an overview of COVID-19 using an organ-based, systematic approach.

Lung function improves after delayed treatment with CNP-miR146a following acute lung injury

Acute respiratory distress syndrome (ARDS) is a highly morbid pulmonary disease characterized by hypoxic respiratory failure. Its pathogenesis is characterized by unrestrained oxidative stress and inflammation, with long-term sequelae of pulmonary fibrosis and diminished lung function. Unfortunately, prior therapeutic ARDS trials have failed and therapy is limited to supportive measures. Free radical scavenging cerium oxide nanoparticles (CNP) conjugated to the anti-inflammatory microRNA-146a (miR146a), termed CNP-miR146a, have been shown to prevent acute lung injury in a pre-clinical model. In this study, we evaluated the potential of delayed treatment with CNP-miR146a at three or seven days after injury to rescue the lung from acute injury. We found that intratracheal CNP-miR146a administered three days after injury lowers pulmonary leukocyte infiltration, reduce inflammation and oxidative stress, lower pro-fibrotic gene expression and collagen deposition in the lung, and ultimately improve pulmonary function.

Impairment in Physical Function and Mental Status in a Survivor of Severe COVID-19 at Discharge from an Acute Care a Hospital: A Case Report

BACKGROUND

Early mobilization and rehabilitation interventions should be provided to patients who survived severe COVID-19 to improve their physical function and activities of daily living (ADL). However, their physical and mental status at discharge has not been well described in Japan. We report the intervention provided for a survivor of severe COVID-19 and his physical and mental status at discharge from an acute care hospital.

CASE REPORT

A 62-year-old man was admitted to our emergency department with a diagnosis of COVID-19 with severe acute respiratory dysfunction. He had complicated intensive care unit-acquired weakness (ICU-AW) and delirium during mechanical ventilation therapy. Rehabilitation intervention was initiated on the seventh day post-admission and was gradually performed according to his respiratory and hemodynamic status. As a result of the rehabilitation intervention, ICU-AW and cognitive function gradually improved. On hospital day 37, he independently performed basic ADL and was discharged. However, he lost approximately 9% of his body weight at discharge. In addition, his hand grip strength and six-minute walking distance were lower and shorter than the reference values, respectively. His mental component summary of the Short Form-8™ was lower than the national standard deviation for the Japanese population.

CONCLUSION

Although survivors of severe COVID-19 who undergo early rehabilitation can be discharged from an acute care hospital, they may have several impairments in their physical and mental status, including muscle function, diffusion capacity, exercise tolerance, and health-related quality of life.

[The role of the intensive care unit after thoracic surgery]

Lung (bronchial) cancer is the leading cause of cancer-related death in Western countries today. Thoracic surgery represents a major therapeutic strategy and the various advances made in recent years have made it possible to develop less and less invasive techniques. That said, the postoperative period may be lengthy, post-surgical approaches need to be more precisely codified, and it matters that the different interventions involved be supported by sound scientific evidence. To date, however, there exists no evidence that preventive postoperative admission to intensive care is beneficial for patients having undergone lung resection surgery without immediate complications. A stratification of the risk of complications taking into consideration the patient's general state of health (e.g., nutritional status, degree of autonomy, etc.), comorbidities and type of surgery could be a useful predictive tool regarding the need for postoperative intensive care. However, serious post-operative complications remain relatively frequent and post-operative management of these intensive care patients is liable to become complex and long-lasting. In the aftermath of the validation of "enhanced recovery after surgery" (ERAS) in thoracic surgery, new protocols are needed to optimize management of patients having undergone pulmonary resection. This article focuses on the main postoperative complications and more broadly on intensive care patient management following thoracic surgery.

Gut-Lung Crosstalk in Sepsis-Induced Acute Lung Injury

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common acute and severe cases of the respiratory system with complicated pathogenesis and high mortality. Sepsis is the leading indirect cause of ALI/ARDS in the intensive care unit (ICU). The pathogenesis of septic ALI/ARDS is complex and multifactorial. In the development of sepsis, the disruption of the intestinal barrier function, the alteration of gut microbiota, and the translocation of the intestinal microbiome can lead to systemic and local inflammatory responses, which further alter the immune homeostasis in the systemic environment. Disruption of homeostasis may promote and propagate septic ALI/ARDS. In turn, when ALI occurs, elevated levels of inflammatory cytokines and the shift of the lung microbiome may lead to the dysregulation of the intestinal microbiome and the disruption of the intestinal mucosal barrier. Thus, the interaction between the lung and the gut can initiate and potentiate sepsis-induced ALI/ARDS. The gut–lung crosstalk may be a promising potential target for intervention. This article reviews the underlying mechanism of gut-lung crosstalk in septic ALI/ARDS.

Evidence-Based Mechanical Ventilatory Strategies in ARDS

Acute respiratory distress syndrome (ARDS) remains one of the leading causes of morbidity and mortality in critically ill patients despite advancements in the field. Mechanical ventilatory strategies are a vital component of ARDS management to prevent secondary lung injury and improve patient outcomes. Multiple strategies including utilization of low tidal volumes, targeting low plateau pressures to minimize barotrauma, using low FiO₂ (fraction of inspired oxygen) to prevent injury related to oxygen free radicals, optimization of positive end expiratory pressure (PEEP) to maintain or improve lung recruitment, and utilization of prone ventilation have been shown to decrease morbidity and mortality. The role of other mechanical ventilatory strategies like non-invasive ventilation, recruitment maneuvers, esophageal pressure monitoring, determination of optimal PEEP, and appropriate patient selection for extracorporeal support is not clear. In this article, we review evidence-based mechanical ventilatory strategies and ventilatory adjuncts for ARDS.

Blood Filters in Children with COVID-19 and AKI: A Review

COVID-19 has challenged the global healthcare system through rapid proliferation and lack of existing treatment resulting in over 180 million cases and 3.8 million deaths since December 2019. Although pediatric patients only comprise 1-2% of diagnosed cases, their incidence of acute kidney injury ranges from 8.2% to 18.2% compared to 49% in adults. Severe infection, initiated by dysregulated host response, can lead to multiorgan failure. In this review, we focus on the use of various blood filters approved for use in pediatric kidney replacement therapy to mitigate adverse effects of severe illness. Therapeutic effects of these blood filters range from cytokine removal (CytoSorb, HA330, HCO/MCO), endotoxin removal (Toraymyxin, CPFA), both cytokine and endotoxin removal (oXiris), and non-specific removal of proteins (PMMA) that have already been established and can be used to mitigate the various effects of the cytokine storm syndrome in COVID-19.

Emergency room comprehensive assessment of demographic, radiological, laboratory and clinical data of patients with COVID-19: determination of its prognostic value for in-hospital mortality

Mortality risk in COVID-19 patients is determined by several factors. The aim of our study was to adopt an integrated approach based on clinical, laboratory and chest x-ray (CXR) findings collected at the patient's admission to Emergency Room (ER) to identify prognostic factors. Retrospective study on 346 consecutive patients admitted to the ER of two North-Western Italy hospitals between March 9 and April 10, 2020 with clinical suspicion of COVID-19 confirmed by reverse transcriptase-polymerase reaction chain test (RT-PCR), CXR performed within 24 h (analyzed with two different scores) and recorded prognosis. Clinical and laboratory data were collected. Statistical analysis on the features of 83 in-hospital dead vs 263 recovered patients was performed with univariate (uBLR), multivariate binary logistic regression (mBLR) and ROC curve analysis. uBLR identified significant differences for several variables, most of them intertwined by multiple correlations. mBLR recognized as significant independent predictors for in-hospital mortality age > 75 years, C-reactive protein (CRP) > 60 mg/L, PaO₂/FiO₂ ratio (P/F) < 250 and CXR "Brixia score" > 7. Among the patients with at least two predictors, the in-hospital mortality rate was 58% against 6% for others [p < 0.0001; RR = 7.6 (4.4-13)]. Patients over 75 years had three other predictors in 35% cases against 10% for others [p < 0.0001, RR = 3.5 (1.9-6.4)]. The greatest risk of death from COVID-19 was age above 75 years, worsened by elevated CRP and CXR score and reduced P/F. Prompt determination of these data at admission to the emergency department could improve COVID-19 pretreatment risk stratification.

Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) is a prevalent and important cause of respiratory failure. Underlying causes include pulmonary and non-pulmonary aetiologies. ARDS is acute hypoxaemic respiratory failure associated with non-cardiogenic pulmonary oedema, reduced pulmonary compliance, and can lead to lung fibrosis. In addition to treating the underlying cause, often the mainstay of the management of ARDS is invasive mechanical ventilation. This can perpetuate lung injury—ventilator-associated lung injury (VALI). Despite recent advances in our understanding of this, ARDS-associated morbidity and mortality remains high. This chapter discusses the pathophysiology of ARDS and its management, including mechanical ventilation, adjunctive therapies, and some recently trialed pharmacotherapies.

Impact of Hydrocortisone and of CRH Infusion on the Hypothalamus-Pituitary-Adrenocortical Axis of Septic Male Mice

PURPOSE

Sepsis is hallmarked by high plasma cortisol/corticosterone (CORT), low adrenocorticotropic hormone (ACTH), and high pro-opiomelanocortin (POMC). While corticotropin-releasing hormone-(CRH) and arginine-vasopressin (AVP)-driven pituitary POMC expression remains active, POMC processing into ACTH becomes impaired. Low ACTH is accompanied by loss of adrenocortical structure, although steroidogenic enzymes remain expressed. We hypothesized that treatment of sepsis with hydrocortisone (HC) aggravates this phenotype whereas CRH infusion safeguards ACTH-driven adrenocortical structure.

METHODS

In a fluid-resuscitated, antibiotics-treated mouse model of prolonged sepsis, we compared the effects of HC and CRH infusion with placebo on plasma ACTH, POMC, and CORT; on markers of hypothalamic CRH and AVP signaling and pituitary POMC processing; and on the adrenocortical structure and markers of steroidogenesis. In adrenal explants, we studied the steroidogenic capacity of POMC.

RESULTS

During sepsis, HC further suppressed plasma ACTH, but not POMC, predominantly by suppressing sepsis-activated CRH/AVP-signaling pathways. In contrast, in CRH-treated sepsis, plasma ACTH was normalized following restoration of pituitary POMC processing. The sepsis-induced rise in markers of adrenocortical steroidogenesis was unaltered by CRH and suppressed partially by HC, which also increased adrenal markers of inflammation. Ex vivo stimulation of adrenal explants with POMC increased CORT as effectively as an equimolar dose of ACTH.

CONCLUSIONS

Treatment of sepsis with HC impaired integrity and function of the hypothalamic-pituitary-adrenal axis at the level of the pituitary and the adrenal cortex while CRH restored pituitary POMC processing without affecting the adrenal cortex. Sepsis-induced high-circulating POMC may be responsible for ongoing adrenocortical steroidogenesis despite low ACTH.

Ventilator-Associated Lung Injury

Ventilatory support, while life saving, can also cause or aggravate lung injury through several mechanisms which are encompassed within ventilator-associated lung injury (VALI). The important realizationin the acute respiratory distress syndrome that the “baby” lung resided in non-dependent areas led to the conceptualization of “lung rest” to reduce stress and strain to exposed alveolar units. We discuss concepts and mechanisms within VALI that ultimately induce maladaptive lung responses, as well as, current and future management strategies to detect and mitigate VALI at the bedside.

Personalized medicine using omics approaches in acute respiratory distress syndrome to identify biological phenotypes

In the last decade, research on acute respiratory distress syndrome (ARDS) has made considerable progress. However, ARDS remains a leading cause of mortality in the intensive care unit. ARDS presents distinct subphenotypes with different clinical and biological features. The pathophysiologic mechanisms of ARDS may contribute to the biological variability and partially explain why some pharmacologic therapies for ARDS have failed to improve patient outcomes. Therefore, identifying ARDS variability and heterogeneity might be a key strategy for finding effective treatments. Research involving studies on biomarkers and genomic, metabolomic, and proteomic technologies is increasing. These new approaches, which are dedicated to the identification and quantitative analysis of components from biological matrixes, may help differentiate between different types of damage and predict clinical outcome and risk. Omics technologies offer a new opportunity for the development of diagnostic tools and personalized therapy in ARDS. This narrative review assesses recent evidence regarding genomics, proteomics, and metabolomics in ARDS research.

CircN4bp1 Facilitates Sepsis-Induced Acute Respiratory Distress Syndrome through Mediating Macrophage Polarization via the miR-138-5p/EZH2 Axis

We recently reported the differential circRNA expression patterns of the pulmonary macrophages in sepsis-induced acute respiratory distress syndrome (ARDS) mice model by microarray analysis. However, their function and hidden molecular mechanism in regulation of macrophage activation and inflammation remain poorly understood. In this study, we found that circN4bp1was overexpressed in PBMC and monocytes, and its expression levels were correlated with a poor prognosis in sepsis induced ARDS patients induced by sepsis. Knockdown of circN4bp1 inhibited the lung injury and improved the long-time survival through blunting the M1 macrophage activation in cecal ligation and puncture- (CLP-) induced ARDS mice. Moreover, bioinformatics analysis predicated a circN4bp1/miR-138-5p ceRNA network, which was confirmed by luciferase reporter assay and RNA binding protein immunoprecipitation (RIP). CircN4bp1 affected macrophage differentiation by binding to miR-138-5p, thus regulating the expression of EZH2 in vivo and ex vivo. Lastly, the m6A level of circN4bp1was found to be elevated in ARDS mice; inhibition of m6A methyltransferase METTL3 blocked this response in vitro. Therefore, circN4bp1 can function as a miR-138-5p sponge for the modulation of macrophage polarization through regulation the expression of EZH2 and may serve as a potential target and/or prognostic marker for ARDS patients following sepsis.

Maintenance of low driving pressure in patients with early acute respiratory distress syndrome significantly affects outcomes

Background

Driving pressure (∆P) is an important factor that predicts mortality in acute respiratory distress syndrome (ARDS). We test the hypothesis that serial changes in daily ΔP rather than Day 1 ΔP would better predict outcomes of patients with ARDS.

Methods

This retrospective cohort study enrolled patients admitted to five intensive care units (ICUs) at a medical center in Taiwan between March 2009 and January 2018 who met the criteria for ARDS and received the lung-protective ventilation strategy. ∆P was recorded daily for 3 consecutive days after the diagnosis of ARDS, and its correlation with 60-day survival was analyzed.

Results

A total of 224 patients were enrolled in the final analysis. The overall ICU and 60-day survival rates were 52.7% and 47.3%, respectively. ∆P on Days 1, 2, and 3 was significantly lower in the survival group than in the nonsurvival group (13.8 ± 3.4 vs. 14.8 ± 3.7, p = 0.0322, 14 ± 3.2 vs. 15 ± 3.5, p = 0.0194, 13.6 ± 3.2 vs. 15.1 ± 3.4, p = 0.0014, respectively). The patients were divided into four groups according to the daily changes in ∆P, namely, the low ∆P group (Day 1 ∆P < 14 cmH₂O and Day 3 ∆P < 14 cmH₂O), decrement group (Day 1 ∆P ≥ 14 cmH₂O and Day 3 ∆P < 14 cmH₂O), high ∆P group (Day 1 ∆P ≥ 14 cmH₂O and Day 3 ∆P ≥ 14 cmH₂O), and increment group (Day 1 ∆P < 14 cmH₂O and Day 3 ∆P ≥ 14 cmH₂O). The 60-day survival significantly differed among the four groups (log-rank test, p = 0.0271). Compared with the low ΔP group, patients in the decrement group did not have lower 60-day survival (adjusted hazard ratio 0.72; 95% confidence interval [CI] 0.31–1.68; p = 0.4448), while patients in the increment group had significantly lower 60-day survival (adjusted hazard ratio 1.96; 95% CI 1.11–3.44; p = 0.0198).

Conclusions

Daily ∆P remains an important predicting factor for survival in patients with ARDS. Serial changes in daily ΔP might be more informative than a single Day 1 ΔP value in predicting survival of patients with ARDS.

Outcome of Critically Ill COVID-19 Patients According to the Setting of Corticosteroid Initiation-A Retrospective Observational Cohort Study

(1) Background: Corticosteroids lower 28-day all-cause mortality in critically ill COVID-19 patients. However, the outcome of COVID-19 patients referred to the intensive care unit (ICU) for respiratory deterioration despite corticosteroids initiated during hospitalization before ICU admission has been poorly investigated. Our objective was to determine survival according to corticosteroid initiation setting. (2) Methods: We conducted a cohort study including all successive critically ill COVID-19 patients treated with corticosteroids and managed in our ICU. We compared survival, whether corticosteroids were initiated before (Cb-group) or after ICU admission (Ca-group), using a propensity score matching. (3) Results: Overall, 228 patients (67 years (56–74); 168M/60F; invasive mechanical ventilation on admission, 17%) were included with 63 patients in the Cb-group and 165 patients in the Ca-group. Survival to hospital discharge was 43% versus 69%, respectively (p = 0.001). In a multivariable analysis, factors associated with death were age (odds ratio, 1.07; 95%-confidence interval, (1.04–1.11); p < 0.0001), the sequential organ failure assessment (SOFA) score on ICU admission (1.30 (1.14–1.50); p = 0.0001) and corticosteroid initiation before ICU admission (2.64 (1.30–5.43); p = 0.007). No significant differences in outcome related to corticosteroid regimen were found. (4) Conclusions: Critically ill COVID-19 patients transferred to the ICU with deterioration despite corticosteroids initiated before admission have a less favorable outcome than patients receiving corticosteroids initiated after ICU admission.

ECMO use in Germany: An analysis of 29,929 ECMO runs

Background

Extracorporeal Membrane Oxygenation (ECMO) use is increasing despite limited evidence. The aim of this study was to demonstrate heterogeneity of ECMO use and its association with hospital size and annual frequency in Germany.

Methods

This is a database analysis of all ECMO cases in Germany from 2010 to 2016 using the German Diagnosis Related Groups (DRG) coding system for ECMO.

Results

During the study period, 510 hospitals performed 29,929 ECMO runs (12,572 vvECMO, 11,504 vaECMO, 1993 pECLA) with an increase over time. Mortality ranged between 58% and 66% for vaECMO cases and 66% and 53% for vvECMO cases. 304 (61%) hospitals performed only one ECMO per year. 78%% of all ECMO runs were performed in centres with more than 20 cases per year and more than half of all ECMO runs were performed in hospitals with >1.000 beds. Mortality for vv and vaECMO was highest in very small hospitals (< 200 beds; 70%; 74%) and very large hospitals (>1000 beds; 60%; 62%).

Conclusions

Use of ECMO is still increasing and a substantial proportion of hospitals performs very few ECMO runs. Small hospitals had a significantly higher mortality, but dependence on hospital size and ECMO mortality was irregular.

Current trends in diagnosis and treatment strategies of COVID-19 infection

Coronaviruses are terrifically precise and adapted towards specialized respiratory epithelial cells, observed in organ culture and human volunteers both. This virus is found to possess an unpredictable anti-viral T-cell response which in turn results in T-cell activation and finally apoptosis, leading to cytokine storm and collapse of the whole immune system. The present review provides comprehensive information regarding SARS-CoV-2 infection, mutant strains, and the impact of SARS-COV-2 on vital organs, the pathophysiology of the disease, diagnostic tests available, and possible treatments. It also includes all the vaccines developed so far throughout the world to control this pandemic. Until now, 18 vaccines have been approved by the WHO and further 22 vaccines are in the third trial. This study also provides up-to-date information regarding the drugs repurposed in clinical trials and the recent status of allopathic drugs along with its result. Although vaccines are available, specific treatment is not available for the disease. Furthermore, the effect of vaccines on new variants is a new area of research at this time. Therefore, a preventive attitude is the best approach to fight against this virus.

Incidence of Pneumothorax and Pneumomediastinum in 497 COVID-19 Patients with Moderate-Severe ARDS over a Year of the Pandemic: An Observational Study in an Italian Third Level COVID-19 Hospital

(1) Background: COVID-19 is a novel cause of acute respiratory distress syndrome (ARDS). Indeed, with the increase of ARDS cases due to the COVID-19 pandemic, there has also been an increase in the incidence of cases with pneumothorax (PNX) and pneumomediastinum (PNM). However, the incidence and the predictors of PNX/PMN in these patients are currently unclear and even conflicting. (2) Methods: The present observational study analyzed the incidence of barotrauma (PNX/PNM) in COVID-19 patients with moderate-severe ARDS hospitalized in a year of the pandemic, also focusing on the three waves occurring during the year, and treated with positive-pressure ventilation (PPV). We collected demographic and clinical data. (3) Results: During this period, 40 patients developed PNX/PNM. The overall incidence of barotrauma in all COVID-19 patients hospitalized in a year was 1.6%, and in those with moderate-severe ARDS in PPV was 7.2% and 3.8 events per 1000 positive-pressure ventilator days. The incidence of barotrauma in moderate-severe ARDS COVID-19 patients during the three waves was 7.8%, 7.4%, and 8.7%, respectively. Treatment with noninvasive respiratory support alone was associated with an incidence of barotrauma of 9.1% and 2.6 events per 1000 noninvasive ventilator days, of which 95% were admitted to the ICU after the event, due to a worsening of respiratory parameters. The incidence of barotrauma of ICU COVID-19 patients in invasive ventilation over a year was 5.8% and 2.7 events per 1000 invasive ventilator days. There was no significant difference in demographics and clinical features between the barotrauma and non-barotrauma group. The mortality was higher in the barotrauma group (17 patients died, 47.2%) than in the non-barotrauma group (170 patients died, 37%), although this difference was not statistically significant (p = 0.429). (4) Conclusions: The incidence of PNX/PNM in moderate-severe ARDS COVID-19 patients did not differ significantly between the three waves over a year, and does not appear to be very different from that in ARDS patients in the pre-COVID era. The barotrauma does not appear to significantly increase mortality in COVID-19 patients with moderate-severe ARDS if protective ventilation strategies are applied. Attention should be paid to the risk of barotrauma in COVID-19 patients in noninvasive ventilation because the event increases the probability of admission to the intensive care unit (ICU) and intubation.

Acute Respiratory Distress Syndrome: Focus on Viral Origin and Role of Pulmonary Lymphatics

Acute respiratory distress syndrome (ARDS) is a serious affection of the lung caused by a variety of pathologies. Great interest is currently focused on ARDS induced by viruses (pandemic influenza and corona viruses). The review describes pulmonary changes in ARDS and specific effects of the pandemic viruses in ARDS, and summarizes treatment options. Because the known pathogenic mechanisms cannot explain all aspects of the syndrome, the contribution of pulmonary lymphatics to the pathology is discussed. Organization and function of lymphatics in a healthy lung and in resorption of pulmonary edema are described. A future clinical trial may provide more insight into the role of hyaluronan in ARDS but the development of promising pharmacological treatments is unlikely because drugs play no important role in lymphedema therapy.

Inhaled β2 Adrenergic Agonists and Other cAMP-Elevating Agents: Therapeutics for Alveolar Injury and Acute Respiratory Disease Syndrome?

Inhaled long-acting β-adrenergic agonists (LABAs) and short-acting β-adrenergic agonists are approved for the treatment of obstructive lung disease via actions mediated by β2 adrenergic receptors (β2-ARs) that increase cellular cAMP synthesis. This review discusses the potential of β2-AR agonists, in particular LABAs, for the treatment of acute respiratory distress syndrome (ARDS). We emphasize ARDS induced by pneumonia and focus on the pathobiology of ARDS and actions of LABAs and cAMP on pulmonary and immune cell types. β2-AR agonists/cAMP have beneficial actions that include protection of epithelial and endothelial cells from injury, restoration of alveolar fluid clearance, and reduction of fibrotic remodeling. β2-AR agonists/cAMP also exert anti-inflammatory effects on the immune system by actions on several types of immune cells. Early administration is likely critical for optimizing efficacy of LABAs or other cAMP-elevating agents, such as agonists of other Gs-coupled G protein-coupled receptors or cyclic nucleotide phosphodiesterase inhibitors. Clinical studies that target lung injury early, prior to development of ARDS, are thus needed to further assess the use of inhaled LABAs, perhaps combined with inhaled corticosteroids and/or long-acting muscarinic cholinergic antagonists. Such agents may provide a multipronged, repurposing, and efficacious therapeutic approach while minimizing systemic toxicity. SIGNIFICANCE STATEMENT: Acute respiratory distress syndrome (ARDS) after pulmonary alveolar injury (e.g., certain viral infections) is associated with ∼40% mortality and in need of new therapeutic approaches. This review summarizes the pathobiology of ARDS, focusing on contributions of pulmonary and immune cell types and potentially beneficial actions of β2 adrenergic receptors and cAMP. Early administration of inhaled β2 adrenergic agonists and perhaps other cAMP-elevating agents after alveolar injury may be a prophylactic approach to prevent development of ARDS.

Severe COVID-19 acute respiratory distress syndrome in an adult with single-ventricle physiology: a case report

Background

COVID-19 can induce acute respiratory distress syndrome (ARDS). In patients with congenital heart disease, established treatment strategies are often limited due to their unique cardiovascular anatomy and passive pulmonary perfusion.

Case presentation

We report the first case of an adult with single-ventricle physiology and bidirectional cavopulmonary shunt who suffered from severe COVID-19 ARDS. Treatment strategies were successfully adopted, and pulmonary vascular resistance was reduced, both medically and through prone positioning, leading to a favorable outcome.

Conclusion

ARDS treatment strategies including ventilatory settings, prone positioning therapy and cannulation techniques for extracorporeal oxygenation must be adopted carefully considering the passive venous return in patients with single-ventricle physiology.

2021 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Neonatal Life Support; Education, Implementation, and Teams; First Aid Task Forces; and the COVID-19 Working Group

The International Liaison Committee on Resuscitation initiated a continuous review of new, peer-reviewed published cardiopulmonary resuscitation science. This is the fifth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation task force science experts. Topics covered by systematic reviews in this summary include resuscitation topics of video-based dispatch systems; head-up cardiopulmonary resuscitation; early coronary angiography after return of spontaneous circulation; cardiopulmonary resuscitation in the prone patient; cord management at birth for preterm and term infants; devices for administering positive-pressure ventilation at birth; family presence during neonatal resuscitation; self-directed, digitally based basic life support education and training in adults and children; coronavirus disease 2019 infection risk to rescuers from patients in cardiac arrest; and first aid topics, including cooling with water for thermal burns, oral rehydration for exertional dehydration, pediatric tourniquet use, and methods of tick removal. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, according to the Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations or good practice statements. Insights into the deliberations of the task forces are provided in Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces listed priority knowledge gaps for further research.

2021 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

The International Liaison Committee on Resuscitation initiated a continuous review of new, peer-reviewed published cardiopulmonary resuscitation science. This is the fifth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation task force science experts. Topics covered by systematic reviews in this summary include resuscitation topics of video-based dispatch systems; head-up cardiopulmonary resuscitation; early coronary angiography after return of spontaneous circulation; cardiopulmonary resuscitation in the prone patient; cord management at birth for preterm and term infants; devices for administering positive-pressure ventilation at birth; family presence during neonatal resuscitation; self-directed, digitally based basic life support education and training in adults and children; coronavirus disease 2019 infection risk to rescuers from patients in cardiac arrest; and first aid topics, including cooling with water for thermal burns, oral rehydration for exertional dehydration, pediatric tourniquet use, and methods of tick removal. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, according to the Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations or good practice statements. Insights into the deliberations of the task forces are provided in Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces listed priority knowledge gaps for further research.

Efficacy and safety of corticosteroids in acute respiratory distress syndrome: An overview of meta-analyses

BACKGROUND

Evidence-based recommendations on the efficacy and safety of corticosteroids in acute respiratory distress syndrome (ARDS) remain a therapeutic challenge. Findings from several systematic reviews and meta-analyses are inconsistent. We aimed to assess the published meta-analyses through a systematic review approach and provide further insight into the current uncertainty and also to perform an updated meta-analysis from all the available primary studies.

METHODOLOGY

We followed the Preferred Reporting Items for Systematic Review (PRISMA) guidelines to establish the patients, intervention, control and outcome (PICO) for reviewing published meta-analyses. Data sources such as PubMed/MEDLINE, SCOPUS, Cochrane and Google Scholar from inception to February 2021 were accessed. Prevention of ARDS, mortality, ventilator-free days, ICU stay and safety in terms of occurrence of adverse effects were the patient-related outcomes. The review also assessed meta-analysis design-related outcomes which includes the quality of meta-analysis, factors contributing to the risk of bias, extent and sources of heterogeneity, publication bias and robustness of findings. AMSTAR-2 checklist assessed the quality of published meta-analyses.

RESULTS

A total of 18 meta-analyses were reviewed comprising a total of 38 primary studies and 3760 patients. Fourteen studies were in ARDS, three in community-acquired pneumonia and one in critical care. The overall quality of meta-analyses was observed to be critically low to high. A non-significant risk of publication bias and non-significant level of heterogeneity was observed in the reviewed meta-analysis. Corticosteroid was significantly effective in preventing ARDS among CAP patients. The effect of corticosteroids on mortality was observed to be still inconsistent, whereas significant improvement was observed with ICU and ventilator outcomes compared with the control group. Our meta-analysis observed a significant reduction of mortality in RCTs (RR: 0.78; 95% CI: 0.61 to 0.99) and the duration of mechanical ventilation (MD: -4.75; 95% CI: -7.63 to -1.88); and a significant increase in ventilator-free days (MD: 6.03; 95% CI: 3.59 to 8.47) and ICU-free days (MD: 8.04; 95% CI: 2.70 to 13.38) in ARDS patients treated with corticosteroids compared with the control group.

CONCLUSION

The quality of included studies ranged from critically low to high demonstrating inconsistency in risk of bias. While older studies found no significant effect, recent meta-analyses of RCTs found a significant mortality reduction in the corticosteroid group with considerable levels of heterogeneity. The updated meta-analysis by our team found a significant reduction in mortality in the pooled estimation of RCTs but not in cohort studies. Corticosteroid therapy was effective in terms of ICU and ventilator outcomes with minimal safety concerns. Future meta-analyses should be well executed with specific research questions and well performed with minimal risk of bias to produce good quality evidence.

A peptide derived from chaperonin 60.1, IRL201104, inhibits LPS-induced acute lung inflammation

Chaperonin 60.1 (Cpn60.1) is a protein derived from Mycobacterium tuberculosis that has been shown, along with its peptide fragment IRL201104, to have beneficial effects in models of allergic inflammation. To further investigate the anti-inflammatory properties of Cpn60.1 and IRL201104, we have investigated these molecules in a model of nonallergic lung inflammation. Mice were treated with Cpn60.1 (0.5-5,000 ng/kg) or IRL201104 (0.00025-2.5 ng/kg), immediately before intranasal instillation of bacterial lipopolysaccharide (LPS). Cytokine levels and cell numbers in mouse bronchoalveolar lavage (BAL) fluid were measured 4 h after LPS administration. In some experiments, mice were depleted of lung-resident phagocytes. Cells from BAL fluid were analyzed for inflammasome function. Human umbilical vein endothelial cells (HUVECs) were analyzed for adhesion molecule expression. Human neutrophils were analyzed for integrin expression, chemotaxis, and cell polarization. Cpn60.1 and IRL201104 significantly inhibited neutrophil migration into the airways, independently of route of administration. This effect of the peptide was absent in TLR4 and annexin A1 knockout mice. Intravital microscopy revealed that IRL201104 reduced leukocyte adhesion and migration into inflamed tissues. However, IRL201104 did not significantly affect adhesion molecule expression in HUVECs or integrin expression, chemotaxis, or polarization of human neutrophils at the studied concentrations. In phagocyte-depleted animals, the anti-inflammatory effect of IRL201104 was not significant. IRL201104 significantly reduced IL-1β and NLRP3 expression and increased A20 expression in BAL cells. This study shows that Cpn60.1 and IRL201104 potently inhibit LPS-induced neutrophil infiltration in mouse lungs by a mechanism dependent on tissue-resident phagocytes and to a much lesser extent, the proresolving factor annexin A1.

Repair of acute respiratory distress syndrome by stromal cell administration (REALIST) trial: A phase 1 trial

BACKGROUND

Mesenchymal stromal cells (MSCs) may be of benefit in acute respiratory distress syndrome (ARDS) due to immunomodulatory, reparative, and antimicrobial actions. ORBCEL-C is a population of CD362 enriched umbilical cord-derived MSCs. The REALIST phase 1 trial investigated the safety and feasibility of ORBCEL-C in patients with moderate to severe ARDS.

METHODS

REALIST phase 1 was an open label, dose escalation trial in which cohorts of mechanically ventilated patients with moderate to severe ARDS received increasing doses (100, 200 or 400 × 10⁶ cells) of a single intravenous infusion of ORBCEL-C in a 3 + 3 design. The primary safety outcome was the incidence of serious adverse events. Dose limiting toxicity was defined as a serious adverse reaction within seven days. Trial registration clinicaltrials.gov NCT03042143.

FINDINGS

Nine patients were recruited between the 7th January 2019 and 14th January 2020. Study drug administration was well tolerated and no dose limiting toxicity was reported in any of the three cohorts. Eight adverse events were reported for four patients. Pyrexia within 24 h of study drug administration was reported in two patients as pre-specified adverse events. A further two adverse events (non-sustained ventricular tachycardia and deranged liver enzymes), were reported as adverse reactions. Four serious adverse events were reported (colonic perforation, gastric perforation, bradycardia and myocarditis) but none were deemed related to administration of ORBCEL-C. At day 28 no patients had died in cohort one (100 × 10⁶), three patients had died in cohort two (200 × 10⁶) and one patient had died in cohort three (400 × 10⁶). Overall day 28 mortality was 44% (n = 4/9).

INTERPRETATION

A single intravenous infusion of ORBCEL-C was well tolerated in patients with moderate to severe ARDS. No dose limiting toxicity was reported up to 400 × 10⁶ cells.

Twenty-four-hour mechanical power variation rate is associated with mortality among critically ill patients with acute respiratory failure: a retrospective cohort study

Objectives

Defined as the energy applied to the respiratory system by ventilator, mechanical power (MP) of ventilation reflects the risk of ventilation-induced lung injury. This study aims to explore the relationship between dynamic changes in MP and prognosis in critically ill patients.

Methods

This was a single-centre retrospective cohort study. Patients receiving mechanical ventilation with acute respiratory failure (ARF) and MP > 10 J/min on admission in the ICU were included. MP (J/min) was calculated as 0.098 × minute ventilation (L/min) × [(peak inspiratory pressure + positive end-expiratory pressure)/2] and the MP variation rate (%) as ([baseline MP − 24-h MP]/baseline MP) × 100. Patients were divided into two groups according to whether MP decreased 24 h after admission (MP-improved group defined as 24-h MP variation rate > 0% vs. MP-worsened group defined as 24-h MP variation rate ≤ 0%).

Results

In total, 14,463 patients were screened between January 2015 and June 2020, and finally, a study cohort of 602 patients was obtained. The MP-improved group had a lower ICU mortality rate than the MP-worsened group (24% vs. 36%; p = 0.005). The 24-h MP variation rate was associated with ICU mortality after adjusting for confounders (odds ratio, 0.906 [95% CI 0.833–0.985]; p = 0.021), while baseline MP (p = 0.909) and 24-h MP (p = 0.059) were not. All MP components improved in the MP-improved group, while minute ventilation and positive end-expiratory pressure contributed to the increase in MP in the MP-worsened group.

Conclusions

The 24-h MP variation rate was an independent risk factor for ICU mortality among ARF patients with elevated MP. Early decreases in MP may provide prognostic benefits in this population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01691-4.

Data automated bag breathing unit for COVID-19 ventilator shortages

BACKGROUND

The COVID-19 pandemic has caused a global mechanical ventilator shortage for treatment of severe acute respiratory failure. Development of novel breathing devices has been proposed as a low cost, rapid solution when full-featured ventilators are unavailable. Here we report the design, bench testing and preclinical results for an 'Automated Bag Breathing Unit' (ABBU). Output parameters were validated with mechanical test lungs followed by animal model testing.

RESULTS

The ABBU design uses a programmable motor-driven wheel assembled for adult resuscitation bag-valve compression. ABBU can control tidal volume (200-800 ml), respiratory rate (10-40 bpm), inspiratory time (0.5-1.5 s), assist pressure sensing (- 1 to - 20 cm H2O), manual PEEP valve (0-20 cm H2O). All set values are displayed on an LCD screen. Bench testing with lung simulators (Michigan 1600, SmartLung 2000) yielded consistent tidal volume delivery at compliances of 20, 40 and 70 (mL/cm H2O). The delivered fraction of inspired oxygen (FiO2) decreased with increasing minute ventilation (VE), from 98 to 47% when VE was increased from 4 to 16 L/min using a fixed oxygen flow source of 5 L/min. ABBU was tested in Berkshire pigs (n = 6, weight of 50.8 ± 2.6 kg) utilizing normal lung model and saline lavage induced lung injury. Arterial blood gases were measured following changes in tidal volume (200-800 ml), respiratory rate (10-40 bpm), and PEEP (5-20 cm H2O) at baseline and after lung lavage. Physiological levels of PaCO2 (≤ 40 mm Hg [5.3 kPa]) were achieved in all animals at baseline and following lavage injury. PaO2 increased in lavage injured lungs in response to incremental PEEP (5-20 cm H2O) (p < 0.01). At fixed low oxygen flow rates (5 L/min), delivered FiO2 decreased with increased VE.

CONCLUSIONS

ABBU provides oxygenation and ventilation across a range of parameter settings that may potentially provide a low-cost solution to ventilator shortages. A clinical trial is necessary to establish safety and efficacy in adult patients with diverse etiologies of respiratory failure.

Corticosteroid use in ARDS and its application to evolving therapeutics for coronavirus disease 2019 (COVID-19): A systematic review

Data regarding the use of corticosteroids for treatment of acute respiratory distress syndrome (ARDS) are conflicting. As the coronavirus disease 2019 (COVID‐19) pandemic progresses, more literature supporting the use of corticosteroids for COVID‐19 and non‐COVID‐19 ARDS have emerged. Glucocorticoids are proposed to attenuate the inflammatory response and prevent progression to the fibroproliferative phase of ARDS through their multiple mechanisms and anti‐inflammatory properties. The purpose of this systematic review was to comprehensively evaluate the literature surrounding corticosteroid use in ARDS (non‐COVID‐19 and COVID‐19) in addition to a narrative review of clinical considerations of corticosteroid use in these patient populations. OVID Medline and EMBASE were searched. Randomized controlled trials evaluating the use of corticosteroids for COVID‐19 and non‐COVID‐19 ARDS in adult patients on mortality outcomes were included. Risk of bias was assessed with the Risk of Bias 2.0 tool. There were 388 studies identified, 15 of which met the inclusion criteria that included a total of 8877 patients. The studies included in our review reported a mortality benefit in 6/15 (40%) studies with benefit being seen at varying time points of mortality follow‐up (ICU survival, hospital, and 28 and 60 days) in the COVID‐19 and non‐COVID‐19 ARDS studies. The two non‐COVID19 trials assessing lung injury score improvements found that corticosteroids led to significant improvements with corticosteroid use. The number of mechanical ventilation‐free days significantly were found to be increased with the use of corticosteroids in all four studies that assessed this outcome. Corticosteroids are associated with improvements in mortality and ventilator‐free days in critically ill patients with both COVID‐19 and non‐COVID‐19 ARDS, and evidence suggests their use should be encouraged in these settings. However, due to substantial differences in the corticosteroid regimens utilized in these trials, questions still remain regarding the optimal corticosteroid agent, dose, and duration in patients with ARDS.

Comparison of prone positioning and extracorporeal membrane oxygenation in acute respiratory distress syndrome: A multicenter cohort study and propensity-matched analysis

Background/Purpose

Both prone positioning and extracorporeal membrane oxygenation (ECMO) are used as rescue therapies for severe hypoxemia in patients with acute respiratory distress syndrome (ARDS). This study compared outcomes between patients with severe influenza pneumonia-related ARDS who received prone positioning and those who received ECMO.

Methods

This retrospective cohort study included eight tertiary referral centers in Taiwan. All patients who were diagnosed as having influenza pneumonia-related severe ARDS were enrolled between January and March 2016. We collected their demographic data and prone positioning and ECMO outcomes from medical records.

Results

In total, 263 patients diagnosed as having ARDS were included, and 65 and 53 of them received prone positioning and ECMO, respectively. The baseline PaO₂/FiO₂ ratio, Acute Physiology and Chronic Health Evaluation II score and Sequential Organ Failure Assessment score did not significantly differ between the two groups. The 60-day mortality rate was significantly higher in the ECMO group than in the prone positioning group (60% vs. 28%, p = 0.001). A significantly higher mortality rate was still observed in the ECMO group after propensity score matching (59% vs. 36%, p = 0.033). In the multivariate Cox regression analysis, usage of prone positioning or ECMO was the single independent predictor for 60-day mortality (hazard ratio: 2.177, p = 0.034).

Conclusion

While the patients receiving prone positioning had better outcome, the causality between prone positioning and the prognosis is unknown. However, the current data suggested that patients with influenza-related ARDS may receive prone positioning before ECMO support.

Neutrophil-to-lymphocyte ratio is a powerful predictor of adult patients with acute respiratory distress syndrome who might benefit from corticosteroid therapy

BACKGROUND

There is no convincing pharmacological treatment for patients withacute respiratory distress syndrome (ARDS). The efficacy of corticosteroids in ARDS patients remains controversial. Neutrophil-to-Lymphocyte Ratio (NLR) has displayed as a good biomarker for inflammation and immune status, and thus a prognostic marker in some critical patients of ARDS. In this study, we hypothesized that NLR could also serve as an indicator for the efficacy of corticosteroid therapy in ARDS patients.

METHODS

Subjects included in this retrospective cohort study with ARDS patients who were admitted to an academic hospital in Wuhan, China, from May 1st, 2020 to April 20th, 2021. Multivariable logisitic regression model was used to evaluate risk factors of 30-day in-hospital mortality and ventilator-free days. Multi-Cox regression model was used to assess the efficacy of corticosteroid treatment in terms of NLR cutoff value.

RESULTS

Among the 357 patients in our study, 89 (24.9%) had NLR≥14.35 and 268 (75.1%) had NLR<14.35. Among them, 53 patients with NLR≥14.35 (58.9%) received corticosteroids and 99 patients with NLR<14.35 (37.1%) received corticosteroids. Post-adjustment analysis (by APACHE II score and age) revealed that corticosteroid treatment was associated with a decreased risk of 30-day mortality in the NLR≥14.35 group but with an increased risk of death in the NLR<14.35 group. Use of corticosteroid in NLR≥14.35 group significantly increased ventilator-free days (7.0 vs. 13.0, P<0.001).

CONCLUSION

NLR may be used to help identify ARDS patients who may benefit from corticosteroid treatment. Large-sized randomized controlled trials are warranted to determine the optimal cutoff value of NLR.

SARS-CoV-2 viral load as a predictor for disease severity in outpatients and hospitalised patients with COVID-19: A prospective cohort study

Introduction

We aimed to examine if severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) cycle quantification (C_q) value, as a surrogate for SARS-CoV-2 viral load, could predict hospitalisation and disease severity in adult patients with coronavirus disease 2019 (COVID-19).

Methods

We performed a prospective cohort study of adult patients with PCR positive SARS-CoV-2 airway samples including all out-patients registered at the Department of Infectious Diseases, Odense University Hospital (OUH) March 9-March 17 2020, and all hospitalised patients at OUH March 10-April 21 2020. To identify associations between C_q-values and a) hospital admission and b) a severe outcome, logistic regression analyses were used to compute odds ratios (OR) and 95% Confidence Intervals (CI), adjusting for confounding factors (aOR).

Results

We included 87 non-hospitalised and 82 hospitalised patients. The median baseline C_q-value was 25.5 (interquartile range 22.3–29.0). We found a significant association between increasing C_q-value and hospital-admission in univariate analysis (OR 1.11, 95% CI 1.04–1.19). However, this was due to an association between time from symptom onset to testing and C_q-values, and no association was found in the adjusted analysis (aOR 1.08, 95% CI 0.94–1.23). In hospitalised patients, a significant association between lower C_q-values and higher risk of severe disease was found (aOR 0.89, 95% CI 0.81–0.98), independent of timing of testing.

Conclusions

SARS-CoV-2 PCR C_q-values in outpatients correlated with time after symptom onset, but was not a predictor of hospitalisation. However, in hospitalised patients lower C_q-values were associated with higher risk of severe disease.

Changes in Oxygenation and Clinical Outcomes with Awake Prone Positioning in Patients with Suspected COVID-19 In Low-Resource Settings: A Retrospective Cohort Study

INTRODUCTION

This study aimed to describe the use of awake prone positioning (APP) and conventional oxygen therapy (COT) in patients with suspected coronavirus disease (COVID-19) and respiratory failure in a limited-resource setting.

METHODS

This was a retrospective cohort study of hospitalized patients aged ≥18 years old who were placed in an awake prone position due to hypoxemic respiratory failure and suspected COVID-19. The patients were selected from a tertiary center in Cartagena, Colombia, between March 1, 2020, and August 31, 2020. Demographic, clinical, and laboratory variables were collated, and all the variables were compared between the groups.

RESULTS

The median age of the participants was 63 (IQR, 48.8-73) years (survivors: 59 [IQR, 43.568] years vs. non-survivors: 70 [IQR, 63-78] years, P ≤ .001). Of the 1470 patients admitted for respiratory symptoms, 732 (49.8%) were hospitalized for more than 24 h, and 212 patients developed respiratory failure and required COT and APP (overall hospital mortality, 34% [73/212]). The mean rank difference in PaO₂/FiO₂ before and after APP was higher in the survivors than in the non-survivors (201.1-252.6, mean rank difference = 51.5, P = .001 vs. 134.1-172.4, mean rank difference = 38.28, P = .24, respectively).

CONCLUSION

While using COT in conjunction with APP can improve respiratory failure in patients with suspected COVID-19 in low-resource settings, persistent hypoxemia after APP can identify patients with higher mortality risk. More evidence is needed to establish the role of this strategy.

CE: A Prone Positioning Protocol for Awake, Nonintubated Patients with COVID-19

ABSTRACT

Prone positioning of critically ill patients with acute respiratory distress syndrome is an accepted therapy done to improve oxygenation and promote weaning from mechanical ventilation. But there is limited information regarding its use outside of the ICU. At one Boston hospital, the influx of patients with suspected or confirmed COVID-19 strained its resources, requiring sweeping systems changes and inspiring innovations in clinical care. This article describes how an interdisciplinary team of clinicians developed a prone positioning protocol for use with awake, nonintubated, oxygen-dependent patients with suspected or confirmed COVID-19 on medical-surgical units, with the hope of hastening their recovery and avoiding deterioration and ICU transfer. A protocol implementation plan and staff educational materials were disseminated via the hospital incident command system and supported through daily leadership huddles. Patient eligibility criteria, including indications and contraindications, and a clear nursing procedure for the implementation of prone positioning with a given patient, were key elements. Nurses' feedback of their experiences with the protocol was elicited through an e-mailed survey. Nearly all respondents reported improvements in patients' oxygen saturation levels, while few respondents reported barriers to protocol implementation. The prone positioning protocol was found to be both feasible for and well tolerated by awake, nonintubated patients on medical-surgical units, and can serve as an example for other hospitals during this pandemic.