Search

Given the important role of patient-ventilator assessments in ensuring the safety and efficacy of mechanical ventilation, a team of respiratory therapists and a librarian used Grading of Recommendations, Assessment, Development, and Evaluation methodology to make the following recommendations: (1) We recommend assessment of plateau pressure to ensure lung-protective ventilator settings (strong recommendation, high certainty); (2) We recommend an assessment of tidal volume (VT) to ensure lung-protective ventilation (4-8 mL/kg/predicted body weight) (strong recommendation, high certainty); (3) We recommend documenting VT as mL/kg predicted body weight (strong recommendation, high certainty); (4) We recommend an assessment of PEEP and auto-PEEP (strong recommendation, high certainty); (5) We suggest assessing driving pressure to prevent ventilator-induced injury (conditional recommendation, low certainty); (6) We suggest assessing FIO2 to ensure normoxemia (conditional recommendation, very low certainty); (7) We suggest telemonitoring to supplement direct bedside assessment in settings with limited resources (conditional recommendation, low certainty); (8) We suggest direct bedside assessment rather than telemonitoring when resources are adequate (conditional recommendation, low certainty); (9) We suggest assessing adequate humidification for patients receiving noninvasive ventilation (NIV) and invasive mechanical ventilation (conditional recommendation, very low certainty); (10) We suggest assessing the appropriateness of the humidification device during NIV and invasive mechanical ventilation (conditional recommendation, low certainty); (11) We recommend that the skin surrounding artificial airways and NIV interfaces be assessed (strong recommendation, high certainty); (12) We suggest assessing the dressing used for tracheostomy tubes and NIV interfaces (conditional recommendation, low certainty); (13) We recommend assessing the pressure inside the cuff of artificial airways using a manometer (strong recommendation, high certainty); (14) We recommend that continuous cuff pressure assessment should not be implemented to decrease the risk of ventilator-associated pneumonia (strong recommendation, high certainty); and (15) We suggest assessing the proper placement and securement of artificial airways (conditional recommendation, very low certainty). [ABSTRACT FROM AUTHOR]

Despite periodic changes in the clinical definition of ARDS, imaging of the lung remains a central component of its diagnostic identification. Several imaging modalities are available to the clinician to establish a diagnosis of the syndrome, monitor its clinical course, or assess the impact of treatment and management strategies. Each imaging modality provides unique insight into ARDS from structural and/or functional perspectives. This review will highlight several methods for lung imaging in ARDS, emphasizing basic operational and physical principles for the respiratory therapist. Advantages and disadvantages of each modality will be discussed in the context of their utility for clinical management and decision-making. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, acute lung injury (ALI) and ARDS have emerged as critical health concerns, drawing considerable attention from clinicians. The volume of published articles on ALI/ARDS is on the rise, indicating the expanding research interest in this field. However, the precise quantity and quality of studies on ALI/ARDS remain unclear. Consequently, we employed bibliometric and visual techniques to comprehensively analyze the patterns and focal points of these articles. METHODS: To investigate the characteristics of highly referenced papers on ALI/ARDS and offer insights into the progress and advancements in research on ALI/ARDS, we conducted a comprehensive search in the core Web of Science database for cited articles using the terms "ALI," "acute lung injury," "ARDS," or "acute respiratory distress syndrome." A total of 60,282 citations were retrieved by narrowing the scope to reviews, articles, and publications in English. From the obtained citations, we selected materials for analysis from the top 100 articles with the highest number of citations. Subsequently, the articles were visualized and analyzed using VOSviewer, CiteSpace, and bibliometric techniques. This analysis focused on identifying trends related to authors, journals, countries, institutions, collaborative networks, key words, and other relevant factors in the field of ALI/ARDS research. RESULTS: Among the top 100 cited articles, the highest and lowest number of citations were 6,957 and 451, respectively. The 100 articles were published between 1991-2020, with a peak in publications observed in 2004, 2005, and 2012 (no. = 7). Among 29 journals, The New England Journal of Medicine (no. = 21) had the highest number of publications, followed by the American Journal of Respiratory and Critical Care Medicine (no. = 14). Among the 29 countries represented in the top 100 cited articles, the United States (no. = 51) emerged as the leading country in the number of publications, followed by Canada (no. = 19) (there was some overlap in paper output between countries due to co-publication). The 3 predominant keywords identified in studies within the ALI/ARDS domain were ALI, mechanical ventilation, and PEEP. CONCLUSIONS: This study provides a historical perspective on the scientific advancements in ALI/ARDS research, highlighting the need for further investigation and development in specific areas within the field. Bibliometric analyses revealed that the United States is the predominant force in the field of ALI/ARDS, contributing significantly to its development. Through an examination of highly cited papers on ALI/ARDS, we have identified global research trends, assessed the quality of studies, and identified hot topics in the field of ALI/ARDS. [ABSTRACT FROM AUTHOR]

Background: Prone position (PP) has been widely used in the COVID-19 pandemic for ARDS management. However, the optimal length of a PP session is still controversial. This study aimed to evaluate the effects of prolonged versus standard PP duration in subjects with ARDS due to COVID-19. Methods: This was a single-center, randomized controlled, parallel, and open pilot trial including adult subjects diagnosed with severe ARDS due to COVID-19 receiving invasive mechanical ventilation that met criteria for PP between March-September 2021. Subjects were randomized to the intervention group of prolonged PP (48 h) versus the standard of care PP (-16 h). The primary outcome variable for the trial was ventilator-free days (VFDs) to day 28. Results: We enrolled 60 subjects. VFDs were not significantly different in the standard PP group (18 [interquartile range [IQR] 0-23] VFDs vs 7.5 [IQR 0-19.0] VFDs; difference, -10.5 (95% CI -3.5 to 19.0, P = .08). Prolonged PP was associated with longer time to successful extubation in survivors (13.00 [IQR 8.75-26.00] d vs 8.00 [IQR 5.00-10.25] d; difference, 5 [95% CI 0-15], P = .001). Prolonged PP was also significantly associated with longer ICU stay (18.5 [IQR 11.8-25.3] d vs 11.50 [IQR 7.75-25.00] d, P = .050) and extended administration of neuromuscular blockers (12.50 [IQR 5.75-20.00] d vs 5.0 [IQR 2.0-14.5] d, P = .005). Prolonged PP was associated with significant muscular impairment according to lower Medical Research Council values (59.6 [IQR 59.1-60.0] vs 56.5 [IQR 54.1-58.9], P = .02). Conclusions: Among subjects with severe ARDS due to COVID-19, there was no difference in 28-d VFDs between prolonged and standard PP strategy. However, prolonged PP was associated with a longer ICU stay, increased use of neuromuscular blockers, and greater muscular impairment. This suggests that prolonged PP is not superior to the current recommended standard of care. [ABSTRACT FROM AUTHOR]

The article presents a study which examined whether there is a stabilization of the dependent dorsal lung aeration day after day in supine position (SP) after prone position (PP) between first PP and last PP sessions using electrical impedance tomography (EIT). Topics include dependent-lung recruitment with PP, dependent dorsal-lung de-recruitment after PP, and finding on the correlation between daily percentage of dorsal lung-dependent area collapse in SP and oxygenation response during PP.

Background: In recent years, mechanical power (MP) has emerged as an important concept that can significantly impact outcomes from mechanical ventilation. Several individual components of ventilatory support such as tidal volume (VT), breathing frequency, and PEEP have been shown to contribute to the extent of MP delivered from a mechanical ventilator to patients in respiratory distress/failure. The aim of this study was to identify which common individual setting of mechanical ventilation is more efficient in maintaining safe and protective levels of MP using different modes of ventilation in simulated subjects with ARDS. Methods: We used an interactive mathematical model of ventilator output during volume control ventilation (VCV) with either constant inspiratory flow (VCV-CF) or descending ramp inspiratory flow, as well as pressure control ventilation (PCV). MP values were determined for simulated subjects with mild, moderate, and severe ARDS; and whenever MP > 17 J/min, VT, breathing frequency, or PEEP was manipulated independently to bring back MP to ≤ 17 J/min. Finally, the optimum VT-breathing frequency combinations for MP = 17 J/min were determined with all 3 modes of ventilation. Results: VCV-CF always resulted in the lowest MPs while PCV resulted in highest MPs. Reductions in VT were the most efficient for maintaining safer and protective MP. At targeted MPs of 17 J/min and maximized minute ventilation, the optimum VT-breathing frequency combinations were 250-350 mL for VT and 32-35 breaths/min for breathing frequency in mild ARDS, 200-350 mL for VT and 34-40 breaths/min for breathing frequency in moderate ARDS, and 200-300 mL for VT and 37-45 breaths/min for breathing frequency for severe ARDS. Conclusions: VCV-CF resulted in the lowest MP. VT was the most efficient for maintaining safe and protective MP in a mathematical simulation of subjects with ARDS. In the context of maintaining low and safe MPs, ventilatory strategies with lower-than-normal VT and higher-than-normal breathing frequency will need to be implemented in patients with ARDS. [ABSTRACT FROM AUTHOR]

BACKGROUND: Postextubation respiratory support in pediatric ARDS may be used to support the recovering respiratory system and promote timely, successful liberation from mechanical ventilation. This study's aims were to (1) describe the use of postextubation respiratory support in pediatric ARDS from the time of extubation to hospital discharge, (2) identify potential risk factors for post-extubation respiratory support, and (3) provide preliminary data for future larger studies. METHODS: This pilot single-center prospective cohort study recruited subjects with pediatric ARDS. Subjects' respiratory status up to hospital discharge, the use of postextubation respiratory support, and how it changed over time were recorded. Analysis was performed comparing subjects who received postextubation respiratory support versus those who did not and compared its use among pediatric ARDS severity categories. Multivariable logistic regression was used to determine variables associated with the use of postextubation respiratory support and included oxygenation index (OI), ventilator duration, and weight. RESULTS: Seventy-three subjects with pediatric ARDS, with median age and OI of 4 (0.6-10.5) y and 7.3 (4.9-12.7), respectively, were analyzed. Postextubation respiratory support was provided to 54/73 (74%) subjects: 28/45 (62.2%), 19/21 (90.5%), and 7/7 (100%) for mild, moderate, and severe pediatric ARDS, respectively, (P < .01). OI and mechanical ventilation duration were higher in subjects who received postextubation respiratory support (8.7 [5.4-14] vs 4.6 [3.7-7], P < .001 and 10 [7-17] d vs 4 [2-7] d, P < .001) compared to those who did not. At hospital discharge, 12/67 (18.2%) survivors received home respiratory support (6 subjects died prior to hospital discharge). In the multivariable model, ventilator duration (adjusted odds ratio 1.3 [95% CI 1.0-1.7], P 5 .050) and weight (adjusted odds ratio 0.95 [95% CI 0.91-0.99], P 5 .02) were associated with the use of postextubation respiratory support. CONCLUSIONS: The majority of intubated subjects with pediatric ARDS received respiratory support postextubation, and a substantial proportion continued to require it up to hospital discharge. [ABSTRACT FROM AUTHOR]

The article discusses a study involving subjects with ARDS who were randomized to receive 2 modes of pressure-regulated volume-targeted modes of ventilation, adaptive support ventilation (ASV) and adaptive pressure ventilation (APV) in different order. Cited are a simplified method to determine mechanical power in subjects receiving APV, how optimized mechanical power (MP) calculation can enhance patient safety and outcomes, and the strengths and limitations of the study.

BACKGROUND: High-flow nasal cannula (HFNC) reduces the need for intubation in adult subject with acute respiratory failure. Changes in hypobaric hypoxemia have not been studied for subject with an HFNC in ICUs at altitudes > 2,600 m above sea level. In this study, we investigated the efficacy of HFNC treatment in subjects with COVID-19 at high altitudes. We hypothesized that progressive hypoxemia and the increase in breathing frequency associated with COVID-19 in high altitudes affect the success of HFNC therapy and may also influence the performance of the traditionally used predictors of success and failure. METHODS: This was a prospective cohort study of subjects >18 y with a confirmed diagnosis of COVID-19--induced ARDS requiring HFNC who were admitted to the ICU. Subjects were followed up during the 28 d of HFNC treatment or until failure. RESULTS: One hundred and eight subjects were enrolled. At admission to the ICU, ... delivery between 0.5-0.8 (odds ratio 0.38 [95% CI 0.17-0.84]) was associated with a better response to HFNC therapy than oxygen delivery on admission between 0.8-1.0 (odds ratio 3.58 [95% CI 1.56-8.22]). This relationship continued during follow-ups at 2, 6, 12, and 24 h, with a progressive increase in the risk of failure (odds ratio 24 h 13.99 [95% CI 4.32-45.26]). A new cutoff for the ratio of oxygen saturation (ROX) index (ROX 6 4.88) after 24 h of HFNC administration was demonstrated to be the best predictor of success (odds ratio 11.0 [95% CI 3.3-47.0]). CONCLUSIONS: High-altitude subjects treated with HFNC for COVID-19 showed a high risk of respiratory failure and progressive hypoxemia when ... requirements were > 0.8 after 24 h of treatment. In these subjects, personalized management should include continuous monitoring of individual clinical conditions (such as oxygenation indices, with cutoffs adapted to those corresponding to high-altitude cities). [ABSTRACT FROM AUTHOR]

BACKGROUND: COVID-19 is associated with variable symptoms and clinical sequelae. Studies have examined the clinical course of these patients, finding a prolonged need for invasive ventilation and variable re-intubation rates. However, no research has investigated factors and outcomes related to reintubation secondary to respiratory failure among patients with COVID-19 with ARDS. METHODS: We conducted a single-center, retrospective study on subjects intubated for ARDS secondary to COVID-19. The primary outcome was re-intubation status; secondary outcomes were hospital and ICU stay and mortality. Data were analyzed using between-group comparisons using chisquare testing for categorical information and Student t test for quantitative data. Univariate and multivariate logistic regression was performed to determine factors related to re-intubation and mortality as dependent variables. RESULTS: One hundred and fourteen subjects were included, of which 32% required re-intubation. No between-group differences were detected for most demographic variables or comorbidities. No differences were detected in COVID-19 treatments, noninvasive respiratory support, mechanical circulatory support, or duration of ventilation. Midazolam (odds ratio [OR] 5.55 [95% CI 1.83-16.80], P = .002), fentanyl (OR 3.64 [95% CI 1.26-10.52], P = .02), and APACHE II scores (OR 1.08 [95% CI 1.030-1.147], P = .005) were independently associated with re-intubation (area under the curve 5 0.81). Re-intubated subjects had extended hospital (36.7 6 22.7 d vs 26.1 6 12.1 d, P = .01) and ICU (29.6 ± 22.4 d vs 15.8 ± 10.4 d, P < .001) stays. More subjects died who failed extubation (49% vs 3%, P < .001). Age (OR 1.07 [95% CI 1.02-1.23], P = .005), male sex (OR 4.9 [95% CI 1.08-22.35], P = .041), positive Confusion Assessment Method for the ICU (CAM-ICU) (OR 5.43 [95% CI 1.58-18.62], P = .007), and re-intubation (OR 12.75 [95% CI 2.80-57.10], P < .001) were independently associated with death (area under the curve 5 0.93). CONCLUSIONS: Midazolam, fentanyl, and higher APACHE II scores were independently associated with re-intubation secondary to respiratory failure in subjects with COVID-19--related ARDS. Furthermore, age, male sex, positive CAM-ICU, and re-intubation were independently associated with mortality. Re-intubation also correlated with prolonged hospital and ICU stay. [ABSTRACT FROM AUTHOR]

The article comments on a study which described a cohort of children with critical asthma managed with noninvasive respiratory support (NRS). It cites limitations of the study including its failure to report the reasons individuals were started on the different respiratory support modalities, the criteria for escalating respiratory support, and NRS parameters used. Also noted are the conflicts regarding the use of high-flow nasal cannula in pediatric critical asthma, its failure rate and risks.

Mechanical ventilation is a lifesaving intervention that may also induce further lung injury by exerting excessive mechanical forces on susceptible lung tissue, a phenomenon termed ventilator-induced lung injury (VILI). The concept of mechanical power (MP) aims to unify in one single variable the contribution of the different ventilatory parameters that could induce VILI by measuring the energy transfer to the lung over time. Despite an increasing amount of evidence demonstrating that high MP values can be associated with VILI development in experimental studies, the evidence regarding the association of MP and clinical outcomes remains controversial. In the present review, we describe the different determinants of VILI, the concept and computation of MP, and discuss the experimental and clinical studies related to MP. Currently, due to different limitations, the clinical application of MP is debatable. Further clinical studies are required to enhance our understanding of the relationship between MP and the development of VILI, as well as its potential impact on clinical outcomes. [ABSTRACT FROM AUTHOR]

Despite its significant limitations, the PaO2 /FIO2 remains the standard tool to classify disease severity in ARDS. Treatment decisions and research enrollment have depended on this parameter for over 50 years. In addition, several variables have been studied over the past few decades, incorporating other physiologic considerations such as ventilation efficiency, lung mechanics, and right-ventricular performance. This review describes the strengths and limitations of all relevant parameters, with the goal of helping us better understand disease severity and possible future treatment targets. [ABSTRACT FROM AUTHOR]

Background: In ARDS caused by COVID-19 pneumonia, appropriate adjustment of physiologic parameters based on lung stretch or oxygenation may optimize the ventilatory strategy. This study aims to describe the prognostic performance on 60-d mortality of single and composite respiratory variables in subjects with COVID-19 ARDS who are on mechanical ventilation with a lung-protective strategy, including the oxygenation stretch index combining oxygenation and driving pressure (ΔP). Methods: This single-center observational cohort study enrolled 166 subjects on mechanical ventilation and diagnosed with COVID-19 ARDS. We evaluated their clinical and physiologic characteristics. The primary study outcome was 60-d mortality. Prognostic factors were evaluated through receiver operating characteristic analysis, Cox proportional hazards regression model, and Kaplan-Meier survival curves. Results: Mortality at day 60 was 18.1%, and hospital mortality was 22.9%. Oxygenation, ΔP, and composite variables were tested: oxygenation stretch index ([Formula: see text]/[Formula: see text] divided by ΔP) and ΔP x 4 + breathing frequency (f) (ΔP x 4 + f). At both day 1 and day 2 after inclusion, the oxygenation stretch index had the best area under the receiver operating characteristic curve (oxygenation stretch index on day 1 0.76 (95% CI 0.67-0.84) and on day 2 0.83 (95% CI 0.76-0.91) to predict 60-d mortality, although without significant difference from other indexes. In multivariable Cox regression, ΔP, [Formula: see text]/[Formula: see text], ΔP x 4 + f, and oxygenation stretch index were all associated with 60-d mortality. When dichotomizing the variables, ΔP ≥ 14, [Formula: see text]/[Formula: see text] ≤ 152 mm Hg, ΔP x 4 + f ≥ 80, and oxygenation stretch index < 7.7 showed lower 60-d survival probability. At day 2, after optimization of ventilatory settings, the subjects who persisted with the worse cutoff values for the oxygenation stretch index showed a lower probability of survival at 60 d compared with day 1; this was not the case for other parameters. Conclusions: The oxygenation stretch index, which combines [Formula: see text]/[Formula: see text] and ΔP, is associated with mortality and may be useful to predict clinical outcomes in COVID-19 ARDS. [ABSTRACT FROM AUTHOR]

BACKGROUND: Endotracheal intubation is a common procedure associated with adverse events, including severe desaturation. Many patients receive noninvasive respiratory support to reduce the need for intubation. There are minimal data about the association between noninvasive respiratory support and the risk of a severe desaturation event during intubation. We aim to differentiate patients based on the level of noninvasive respiratory support, analyze the severe desaturation event by groups, and identify modifiable risk factors. METHODS: Oral intubations, excluding tube exchanges or re-intubation after unplanned extubation, from October 2018 through July 2020, at the study site were reviewed. A severe desaturation event was defined as SpO2 < 70% or a >15% decrease from baseline in cyanotic heart disease. We analyzed outcomes by 4 groups: room air/nasal cannula (≤0.5 L/kg/min), high-flow nasal cannula (HFNC) (0.5-2 L/kg/min), high HFNC (62 L/kg/min), and noninvasive ventilation (NIV). RESULTS: Of 243 subjects who were intubated, 31% were receiving room air/nasal cannula, 25% were receiving HFNC, 18% were receiving high HFNC, and 26% were receiving NIV. Twelve percent of all the subjects had a severe desaturation event. In a univariate analysis, the incidence of a severe desaturation event was similar among all levels of respiratory support (P = .14). A severe desaturation event was more likely in those subjects who were receiving FIO2 6 0.6 at the time of the decision to intubate (19.6%) versus FIO2 < 0.6 (8.1%) (P = .02). The duration of non-invasive respiratory support was longer (5 vs 1 h; P = .02) among those with a severe desaturation event. In a regression analysis, when adjusting for 62 intubation attempts pre-intubation, NIV use was independently associated with increased odds of severe desaturation events (odds ratio 3.14, CI 1.08-10.5). CONCLUSIONS: Results of our study suggest that FIO2 > 0.60, the duration of noninvasive respiratory support, and exposure to NIV before an intubation are risk factors of severe desatu- ration events during intubation. [ABSTRACT FROM AUTHOR]

The article proposes a simplified method to assess transpulmonary pressure monitoring based on hypothesis by F. Mojoli and colleagues. Topics discussed include statistical comparison between continuous variables, complete acquisition and recording of esophageal balloon pressure volume (PV) curve, and finding on a dynamic esophageal balloon inflation procedure.

The article presents a study which determined whether respiratory mechanics, oxygenation impairment, social demographics, and comorbid conditions among mechanically ventilated subjects with COVID-19 infections are associated with all-cause mortality. Topics include descriptive characteristics of the sample by mortality status, multivariable analyses for mortality outcome, and limitations of the study.

BACKGROUND: Patient-triggered adaptive pressure control (APC) continuous mandatory ventilation (CMV) (APC-CMV) has been widely adopted as an alternative ventilator mode to patient-triggered volume control (VC) CMV (VC-CMV). However, the comparative effectiveness of the 2 ventilator modes remains uncertain. We sought to explore clinical and implementation factors pertinent to a future definitive randomized controlled trial assessing APC-CMV versus VC-CMV as an initial ventilator mode strategy. The research objectives in our pilot trial tested clinician adherence and explored clinical outcomes. METHODS: In a single-center pragmatic sequential cluster crossover pilot trial, we enrolled all eligible adults with acute respiratory failure requiring mechanical ventilation admitted during a 9-week period to the medical ICU. Two-week time epochs were assigned a priori in which subjects received either APC-CMV or VC-CMV The primary outcome of the trial was feasibility, defined as 80% of subjects receiving the assigned mode within 1 h of initiation of ICU ventilation. The secondary outcome was proportion of the first 24 h on the assigned mode. Finally, we surveyed clinician stakeholders to understand potential facilitators and barriers to conducting a definitive randomized trial. RESULTS: We enrolled 137 subjects who received 152 discreet episodes of mechanical ventilation during time epochs assigned to APC-CMV (n 5 61) and VC-CMV (n 5 91). One hundred and thirty-one episodes were included in the prespecified primary outcome. One hundred and twenty-six (96%) received the assigned mode within the first hour of ICU admission (60 of 61 subjects assigned APC-CMV and 66 of 70 assigned VC-CMV). VC-CMV subjects spent a lower proportion of first 24 h (84% [95% CI 78--89]) on the assigned mode than APC-CMV recipients (95% [95% CI 91--100]). Mixed-methods analyses identified preconceived perceptions of subject comfort by clinicians and need for real-time education to address this concern. CONCLUSIONS: In this pilot pragmatic, sequential crossover trial, unit-wide allocation to a ventilator mode was fea- sible and acceptable to clinicians. [ABSTRACT FROM AUTHOR]

Determination of optimum PEEP levels remains an elusive goal. One factor is the recruitability of the lung, yet this is another difficult determination. Recently, a simple bedside technique, called the recruitment-to-inflation ratio, has been described and validated by comparison to the dual pressure-volume curve method. We describe the prior research and concepts of lung mechanics leading up to this metric and develop some background mathematics that help clinicians understand its meaning. [ABSTRACT FROM AUTHOR]

BACKGROUND: Noninvasive respiratory support (NRS) is widely used in pediatric ICUs (PICUs). However, there is limited experience regarding the utilization of NRS in non-PICU settings. We aimed to evaluate the success rate of NRS in pediatric high-dependency units (PHDUs), identify predictors of NRS failure, quantify adverse events, and assess outcomes. METHODS: We included infants and children (> 7 d to < 13 y old) admitted to PHDU in 2 tertiary hospitals for acute respiratory distress over a 19-month period. Collected data included diagnosis, type and duration of NRS, adverse events, and the need for PICU transfer or invasive ventilation. RESULTS: Two hundred and ninety-nine children were included, with a median age of 7 (interquartile range [IQR] 3-25) months and a median weight of 6.1 (IQR 4.3-10.5) kg. Bronchiolitis (37.5%), pneumonia (34.1%), and asthma (12.7%) were the most frequent diagnoses. Median NRS duration was 2 (IQR 1-3) d. At baseline, median SpO2 was 96% (IQR 90-99); median pH was 7.36 (IQR 7.31-7.41), and median PCO was 44 (IQR 36-53) mm Hg. Overall, 234 (78.3%) children were successfully managed in PHDU, whereas 65 (21.7%) required transfer to PICU. Thirty-eight (12.7%) needed invasive ventilation on a median time of 43.5 (IQR 13.5-108.0) h. On multivariable analysis, maximum FIO2 > 0.5 (odds ratio 4.49 [95% CI 1.36-14.9], P = .01) and PEEP > 7 cm H2O (odds ratio 3.37 [95% CI 1.49-7.61], P = .004) were predictors for NRS failure. Significant apnea, cardiopulmonary resuscitation, and air leak syndrome were reported in 0.3, 0.7, and 0.7% children, respectively. CONCLUSIONS: In our cohort, we found NRS in PHDU safe and effective; however, maximum FIO2 > 0.5 post treatment and PEEP > 7 cm H2O were associated with NRS failure. [ABSTRACT FROM AUTHOR]

The article discusses a study which monitored the areas of hypoventilation in the lungs of subjects with COVID-19-related acute respiratory distress syndrome (ARDS) using electrical impedance tomography (EIT). Topics covered include the relationship between the distribution pattern of hypoventilated regions with low respiratory system compliance and gas exchange, the typical response of subjects to positive end-expiratory pressure (PEEP), and the utility of EIT in detecting lung disease.

BACKGROUND: Acute respiratory failure (ARF) remains the most frequent reason for ICU admission in patients who are immunocompromised. This study reports etiologies and outcomes of ARF in subjects with solid tumors. METHODS: This study was a post hoc analysis of the EFRAIM study, a prospective multinational cohort study that included 1611 subjects who were immunocompromised and with ARF admitted to the ICU. Subjects with solid tumors admitted to the ICU with ARF were included in the analysis. RESULTS: Among the subjects from the EFRAIM cohort, 529 subjects with solid tumors (32.8%) were included in the analysis. At ICU admission, the median (interquartile range) Sequential Organ Failure Assessment score was 5 (3-9). The types of solid tumor were mostly lung cancer (n = 111, 21%), breast cancer (n = 52, 9.8%), and digestive cancer (n = 47, 8.9%). A majority, 379 subjects (71.6%) were full code at ICU admission. The ARF was caused by bacterial or viral infection (n = 220, 41.6%), extrapulmonary sepsis (n = 62, 11.7%), or related to cancer or treatment toxicity (n = 83, 15.7%), or fungal infection (n = 23, 4.3%). For 63 subjects (11.9%), the ARF etiology remained unknown after an extensive diagnostic workup. The hospital mortality rate was 45.7% (n = 232/508). Hospital mortality was independently associated with chronic cardiac failure (odds ratio 1.78, 95% CI 1.09-2.92; P = .02), lung cancer (odds ratio 2.50, 95% CI 1.51-4.19; P < .001), day 1 Sequential Organ Failure Assessment score (odds ratio 1.97, 95% CI 1.32-2.96; P < .001). ARF etiologies other than infectious, related to cancer, or treatment toxicity were associated with better outcomes (odds ratio 0.32, 95% CI 0.16-0.61; P < .001). CONCLUSIONS: Infectious diseases remained the most frequent cause of ARF in subjects with solid tumors admitted to the ICU. Hospital mortality was related to severity at ICU admission, previous comorbidities, and ARF etiologies related to non-malignant causes or pulmonary embolism. Lung tumor was also independently associated with higher mortality. [ABSTRACT FROM AUTHOR]

The article discusses research which examined the long-term health care utilization of survivors of acute respiratory distress syndrome (ARDS) during the first 3 years after discharge from the intensive care unit (ICU). Topics covered include the characteristics of study patients, the extent to which participants use out-patient and in-patient health care up to 36 months after discharge, and the amount of visits to various specialists throughout the 3 years.

Background: Lung-protective ventilation (reduced tidal volume and limited plateau pressure) may lead to CO2 retention. Data about the impact of hypercapnia in patients with ARDS are scarce and conflicting. Methods: We performed a non-interventional cohort study with subjects with ARDS admitted from 2006 to 2021 and with PaO2 /FIO2 ≤ 150 mm Hg. We examined the association between severe hypercapnia (PaCO2 ≥ 50 mm Hg) on the first 5 days after the diagnosis of ARDS and death in ICU for 930 subjects. All the subjects received lung-protective ventilation. Results: Severe hypercapnia was noted in 552 subjects (59%) on the first day of ARDS (day 1); 323/930 (34.7%) died in the ICU. Severe hypercapnia on day 1 was associated with mortality in the unadjusted (odds ratio 1.54, 95% CI 1.16-1.63; P = .003) and adjusted (odds ratio 1.47, 95% CI 1.08-2.43; P = .004) models. In the Bayesian analysis, the posterior probability that severe hypercapnia was associated with ICU death was > 90% in 4 different priors, including a septic prior for this association. Sustained severe hypercapnia on day 5, defined as severe hypercapnia present from day 1 to day 5, was noted in 93 subjects (12%). After propensity score matching, severe hypercapnia on day 5 remained associated with ICU mortality (odds ratio 1.73, 95% CI 1.02-2.97; P = .047). Conclusions: Severe hypercapnia was associated with mortality in subjects with ARDS who received lung-protective ventilation. Our results deserve further evaluation of the strategies and treatments that aim to control CO2 retention. [ABSTRACT FROM AUTHOR]

BACKGROUND: We analyzed bleeding and thrombotic complications in COVID-19--associated ARDS requiring extracorporeal membrane oxygenation (ECMO). METHODS: This was a single-center observational study of adult subjects undergoing ECMO for COVID-19 (n = 67) or all other cause of ARDS (n = 60), excluding trauma patients. RESULTS: In the COVID-19 group, duration of invasive mechanical ventilation prior to ECMO was lower (2 [0-4] d vs 3 [1--6] d) and ECMO retrieval less frequent (71% vs 87%). No significant differences were found in Simplified Acute Physiology Score II, Acute Physiology and Chronic Health Evaluation II (APACHE II), or in the in-hospital survival predicted by the Respiratory ECMO Survival Prediction score. During the first 7 d of ECMO support, the COVID-19 group presented higher platelets and fibrinogen, lower activated partial thromboplastin time, but no differences in D-dimer. Thrombotic complications were similar between groups. Higher rates of severe bleeding, namely airway bleeding (37.3% vs 15.0%) and hemothorax (13.4% vs 3.3%), were found in COVID-19, with lower hemoglobin and higher red blood cell transfusions. COVID-19 ARDS was associated with longer ECMO duration (47 [17-80] d vs 19 [12-30] d) and absence of a statistically significant difference concerning in-hospital mortality. CONCLUSIONS: COVID-19--associated ARDS requiring ECMO presented high rates of severe bleeding complications and a protracted course. Further studies are needed to clarify the risks and benefits of ECMO in severe COVID-19--associated ARDS. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sedation in intensive care is fundamental for optimizing clinical outcomes. For many years the world has been facing high rates of opioid use, and to combat the increasing opioid addiction plans at both national and international level have been implemented.1 The COVID-19 pandemic posed a major challenge for health systems and also increased the use of sedatives and opioid analgesia for prolonged periods of time, and at high doses, in a significant proportion of patients. In our institutions, the shortage of many drugs for intravenous (IV) analgosedation forces us to alternatives to replace out-of-stock drugs or to seek sedation goals, which are difficult to obtain with traditional drugs at high doses.2 METHODS: This was an analytical retrospective cohort study evaluating the follow-up of subjects with inclusion criteria from ICU admission to discharge (alive or dead). Five end points were measured: need for high-dose opioids (≥200 µg/h), comparison of inhaled versus IV sedation of opioid analgesic doses, midazolam dose, need for muscle relaxant, and risk of delirium. RESULTS: A total of 283 subjects were included in the study, of whom 230 were administered IV sedation and 53 inhaled sedation. In the inhaled sedation group, the relative risks (RRs) were 0.5 (95% CI 0.4-0.8, P = .045) for need of high-dose fentanyl, 0.3 (95% CI 0.20-0.45, P < .001) for need of muscle relaxant, and 0.8 (95% CI 0.61-1.15, P = .25) for risk of delirium. The median difference of fentanyl dose between the inhaled sedation and IV sedation groups was 61 µg/h or 1,200 µg/d (2.2 ampules/d, P < .001), and that of midazolam dose was 5.7 mg/h. CONCLUSIONS: Inhaled sedation was associated with lower doses of opioids, benzodiazepines, and muscle relax-ants compared to IV sedation. This therapy should be considered as an alternative in critically ill patients requiring prolonged ventilatory support and where IV sedation is not possible, always under adequate supervision of ICU staff. [ABSTRACT FROM AUTHOR]

BACKGROUND: Driving pressure (DP) and mechanical power (MP) may be important mediators of lung injury in ARDS; however, there is little evidence for strategies directed at reducing these parameters. We applied predictive modeling to estimate the effects of modifying ventilator parameters on DP and MP. METHODS: Two thousand six hundred twenty-two subjects with ARDS (Berlin criteria) from the Medical Information Mart for Intensive Care IV version 1.0 database admitted to the ICU at Beth Israel Deaconess Medical Center between 2008-2019 were included. Flexible confounding-adjusted regression models for time-varying data were fit to estimate the effects of adjusting PEEP and tidal volume (VT) on DP and adjusting VT and breathing frequency on MP. RESULTS: Reduction in VT reduced DP and MP, with more pronounced effect on MP with lower compliance. Strategies reducing frequency consistently increased MP (when VT was adjusted to maintain consistent minute ventilation). Adjustment of PEEP yielded a U-shaped effect on DP. CONCLUSIONS: This novel conditional modeling confirmed expected response patterns for DP, with the response to adjustments depending on subjects' lung mechanics. Furthermore, a VT-driven approach should be favored over a breathing frequency-driven approach when aiming to reduce MP. [ABSTRACT FROM AUTHOR]

BACKGROUND: COVID-19--related ARDS is characterized by severe hypoxemia with initially preserved lung compliance and impaired ventilation/perfusion (V/Q) matching. PEEP can increase end-expiratory lung volume, but its effect on V/Q mismatch in COVID-19--related ARDS is not clear. METHODS: We enrolled intubated and mechanically ventilated subjects with COVID-19 ARDS and used the automatic lung parameter estimator (ALPE) to measure V/Q. Respiratory mechanics measurements, shunt, and V/Q mismatch (low V/Q and high V/Q) were collected at 3 PEEP levels (clinical PEEP = intermediate PEEP, low PEEP [clinical - 50%], and high PEEP [clinical + 50%]). A mixed-effect model was used to evaluate the impact of PEEP on V/Q. We also investigated if PEEP might have a different effect on V/Q mismatch in 2 different respiratory mechanics phenotypes, that is, high elastance/low compliance (phenotype H) and low elastance/high compliance (phenotype L). RESULTS: Seventeen subjects with COVID-related ARDS age 66 [60-71] y with a PaO2/FIO2 of 141 ± 74 mm Hg were studied at low PEEP = 5.6 ± 2.2 cm H2O, intermediate PEEP = 10.6 ± 3.8 cm H2O, and high PEEP = 15 ± 5 cm H2O. Shunt, low V/Q, high V/Q, and alveolar dead space were not significantly influenced, on average, by PEEP. Respiratory system compliance decreased significantly when increasing PEEP without significant variation of PaO2/FIO2 (P = .26). In the 2 phenotypes, PEEP had opposite effects on shunt, with a decrease in the phenotype L and an increase in phenotype H (P = .048). CONCLUSIONS: In subjects with COVID-related ARDS placed on invasive mechanical ventilation for > 48 h, PEEP had a heterogeneous effect on V/Q mismatch and, on average, higher levels were not able to reduce shunt. The subject's compliance could influence the effect of PEEP on V/Q mismatch since an increased shunt was observed in subjects with lower compliance, whereas the opposite occurred in those with higher compliance. [ABSTRACT FROM AUTHOR]

BACKGROUND: ARDS is a serious complication of hematopoietic stem cell transplant (HSCT). Pre-transplant risk factors for developing ARDS after HSCT have been recently identified. The objective of this study was to better understand post-transplant risk factors for developing ARDS after HSCT. METHODS: This was a nested case-control study. ARDS cases were matched to hospitalized non-ARDS controls by age, type of transplantation (allogeneic vs autologous), and time from transplantation. In a conditional logistic regression model, any potential risk factors were adjusted a priori for risk factors known to be associated with ARDS development. RESULTS: One hundred and seventy ARDS cases were matched 1:1 to non-ARDS hospitalized controls. Pre-admission, cases were more likely to be on steroids (odds ratio [OR] 1.90 [1.13-3.19], P 5 .02). At time of admission, cases had lower platelet count (OR 0.95 [0.91-0.99], P 5 .02), lower bicarbonate (OR 0.94 [0.88-0.99], P 5 .035), and higher creatinine (OR 1.91 [1.23-2.94], P 5 .004). During the first 24 h after admission, cases were more likely to have received transfusion (OR 2.41 [1.48-3.94], P < .001), opioids (OR 2.94 [1.67-5.18], P < .001), and have greater fluid administration (OR 1.52 [1.30-1.78], P < .001). During the hospitalization, ARDS cases had higher temperature (OR 1.77 [1.34-2.33], P < .001) and higher breathing frequency (OR 1.52 [1.33-1.74], P < .001). ARDS cases were more likely to have had sepsis (OR 68.0 [15.2-301.7], P < .001), bloodstream infection (OR 4.59 [2.46-8.57], P < .001), and pneumonia (OR 9.76 [5.01-19.00], P < .001). CONCLUSIONS: Several post-transplant predictors of ARDS development specific to the HSCT population were identified in the pre-hospital and early in-hospital domains. These findings can provide insights into causal mechanisms of ARDS development and be used to develop HSCT-specific risk prediction models. [ABSTRACT FROM AUTHOR]

BACKGROUND: The evolution of compliance and driving pressure in ARDS and the effects of time spent on noninvasive respiratory support prior to intubation have not been well studied. We conducted this study to assess the effect of the duration of noninvasive respiratory support prior to intubation (ie, noninvasive ventilation [NIV], high-flow nasal cannula [HFNC], or a combination of NIV and HFNC) on static compliance and driving pressure and retrospectively describe its trajectory over time for COVID-19 and non--COVID-19 ARDS while on mechanical ventilation. METHODS: This is a retrospective analysis of prospectively collected data from one university-affiliated academic medical center, one rural magnet hospital, and 3 suburban community facilities. A total of 589 subjects were included: 55 COVID-19 positive, 137 culture positive, and 397 culture-negative subjects. Static compliance and driving pressure were calculated at each 8-h subject-ventilator assessment. RESULTS: Days of pre-intubation noninvasive respiratory support were associated with worse compliance and driving pressure but did not moderate any trajectory. COVID-19--positive subjects showed non-statistically significant worsening compliance by 0.08 units per subject-ventilator assessment (P 5 .24), whereas COVID-19--negative subjects who were either culture positive or negative showed statistically significant improvement (0.12 and 0.18, respectively; both P < .05); a statistically similar but inverse pattern was observed for driving pressure. CONCLUSIONS: In contrast to non--COVID-19 ARDS, COVID-19 ARDS was associated with a more ominous trajectory with no improvement in static compliance or driving pressures. Though there was no association between days of pre-intubation noninvasive respiratory support and mortality, its use was associated with worse overall compliance and driving pressure. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ventilatory parameters measured soon after initiation of mechanical ventilation have limited ability to predict outcome of COVID-19-related ARDS. We hypothesized that ventilatory parameters measured after one week of mechanical ventilation might differ between survivors and non-survivors. METHODS: One hundred twenty-seven subjects with COVID-related ARDS had gas exchange and lung mechanics assessed on the day of intubation and one week later. The main parameters of interest were ..., ventilatory ratio (VR), respiratory system compliance (CRS), and a composite score that was calculated as (...) x CRS/VR. The primary outcome was death in the ICU. RESULTS: Of the 127 subjects, 42 (33%) died in the ICU and 85 (67%) were successfully extubated. On the day of intubation, ..., CRS, and composite score of survivors and non-survivors were similar, but survivors had a lower VR. At one week, as compared to survivors, non-survivors had a significantly higher VR (2.04 ± 0.76 vs 1.60 ± 0.43, P < .001), lower CRS (27.4 ± 6.4 mL/cm H2O vs 32.4 ± 9.3 mL/cm H2O, P = .002), and lower composite score (20.6 ± 11.9 vs 34.5 ± 18.6, P < .001), with no statistically significant difference in ... (137 ± 49 vs 155 ± 48, P = .08). CONCLUSIONS: In subjects with COVID ARDS, parameters that reflect dead space (VR), lung mechanics (CRS), and a combined score that included PaO2 /FIO2, VR, and CRS differed between survivors and non-survivors after one week of mechanical ventilation but with considerable overlap of values between survivors and non-survivors. [ABSTRACT FROM AUTHOR]

In the article, the authors present their study which evaluated the feasibility of a specific protocol for reducing respiratory rate in patients with COVID-19-related acute respiratory distress syndrome (ARDS) and the effect of reducing the frequency on hemodynamics, respiratory mechanics, and mechanical power. Also cited are how mechanical ventilation could promote the phenomenon called ventilator-induced lung injury (VILI), and the strategies to prevent VILI like the use of prone positioning.

BACKGROUND: Noninvasive ventilation (NIV) has become more studied in immunocompromised patients. However, it has not been studied in hematopoietic cell transplantation (HCT) recipients, who have higher mortality and higher pulmonary complication rates than other immuno-compromised patients. This population may be prone to negative effects from this treatment modality. The aim of this study was to determine whether NIV use is associated with worse outcomes in this vulnerable patient population. METHODS: A secondary analysis of a retrospective multi-center database was performed. Twelve pediatric ICUs across the United States enrolled HCT subjects from 2009-2014 that were admitted to the pediatric ICU (PICU) with the diagnosis of acute respiratory failure. Subjects exposed to NIV prior to intubation were compared against those not exposed to NIV. Our primary outcome was all-cause mortality at 90 d; secondary outcomes included ventilator-free days (VFD) at 28 d and development of pediatric ARDS. Multivariable logistic and linear regression models were constructed using variables significant on univariable analysis. RESULTS: Two-hundred eleven subjects were included. Of these, 82 (39%) received NIV prior to intubation. Those that received NIV prior to intubation were older (13 vs 6 y, P < .001) and more commonly diagnosed with respiratory distress (90% vs 74%, P = .004). On multivariable analysis, NIV use prior to intubation was associated with a higher PICU mortality (hazard ratio 1.51 [95% CI 1.18-2.28], P = .02) and fewer VFD at 28 d (β -3.50 [95% CI -6.09 to 0.91], P = .008). Those with NIV exposure prior to intubation also had higher rates of development of pediatric ARDS (95% vs 78%, P = .001). CONCLUSIONS: In this cohort of children post-HCT, NIV use prior to intubation was associated with worse outcomes. The benefits and risks of NIV in this patient population should be carefully evaluated prior to its use, and careful patient selection is crucial for its optimal utilization. [ABSTRACT FROM AUTHOR]

BACKGROUND: How indices specific to respiratory compromise contribute to prognostication in patients with ARDS is not well characterized in general clinical populations. The primary objective of this study was to identify variables specific to respiratory failure that might add prognostic value to indicators of systemic illness severity in an observational cohort of subjects with ARDS. METHODS: Fifty subjects with ARDS were enrolled in a single-center, prospective, observational cohort. We tested the contribution of respiratory variables (oxygenation index, ventilatory ratio [VR], and the radiographic assessment of lung edema score) to logistic regression models of 28-d mortality adjusted for indicators of systemic illness severity (the Acute Physiology and Chronic Health Evaluation [APACHE] III score or severity of shock as measured by the number of vasopressors required at baseline) using likelihood ratio testing. We also compared a model utilizing APACHE III with one including baseline number of vasopressors by comparing the area under the receiver operating curve (AUROC). RESULTS: VR significantly improved model performance by likelihood ratio testing when added to APACHE III (P = .036) or the number of vasopressors at baseline (P = .01). Number of vasopressors required at baseline had similar prognostic discrimination to the APACHE III. A model including the number of vasopressors and VR (AUROC 0.77 [95% CI 0.64-0.90]) was comparable to a model including APACHE III and VR (AUROC 0.81 [95% CI 0.68-0.93]; P for comparison = .58.). CONCLUSIONS: In this observational cohort of subjects with ARDS, the VR significantly improved discrimination for mortality when combined with indicators of severe systemic illness. The number of vasopressors required at baseline and APACHE III had similar discrimination for mortality when combined with VR. VR is easily obtained at the bedside and offers promise for clinical prognostication. [ABSTRACT FROM AUTHOR]

BACKGROUND: Prone positioning reduces mortality in patients with moderate/severe ARDS. It remains unclear which physiological parameters could guide clinicians to assess which patients are likely to benefit from prone position. This study aimed to determine the association between relative changes in physiological parameters at 24 h of prone positioning and ICU mortality in adult subjects with ARDS. METHODS: We conducted a cohort study using the VENTILA database, including adults with ARDS receiving prone positioning. We used multivariable logistic regression to assess the association between relative changes in physiological parameters (P.../F..., dynamic driving pressure, P..., and ventilatory ratio defined as [minute ventilation [mL/min] x P... [mm Hg]]/[predicted body weight X 100 [mL/min] x 37.5 [mm Hg] with ICU mortality) (primary outcome). We report adjusted odds ratios with 95% CI as measures of association. RESULTS: We included 156 subjects of which 82 (53%) died in the ICU. A relative decline in the ventilatory ratio at 24 h was associated with lower ICU mortality (odds ratio 0.80 [95% CI 0.66-0.97], every 10% decrease). Relative changes in P.../F... (odds ratio 0.89 [95% CI 0.77-1.03], every 25% increase), P... (odds ratio 0.97 [95% CI 0.82-1.16], every 10% decrease), and dynamic driving pressure (odds ratio 0.98 [95% CI 0.89-1.07], every 10% decrease) were not associated with ICU mortality. CONCLUSIONS: In subjects with ARDS receiving prone positioning, a relative decline in the ventilatory ratio at 24 h was associated with lower ICU mortality. [ABSTRACT FROM AUTHOR]

BACKGROUND: For almost 50 years, pediatricians used adult guidelines to diagnose ARDS. In 2015, specific criteria for pediatric ARDS were defined. However, it remains unclear how frequently providers recognize pediatric ARDS and whether recognition affects adherence to consensus recommendations. METHODS: This was a mixed-method, retrospective study of mechanically ventilated pediatric subjects after the release of the pediatric ARDS recommendation statement. Pediatric ARDS cases were identified according to the new criteria. Provider recognition was defined by documentation in the medical record. Pediatric ARDS subjects with and without provider recognition were compared quantitatively according to clinical characteristics, adherence to lung-protective ventilation (LPV), adjunctive therapies, and outcomes. A qualitative document analysis (QDA) was performed to evaluate knowledge and beliefs surrounding the Pediatric Acute Lung Injury Consensus Conference recommendations. RESULTS: Of 1,983 subject encounters, pediatric ARDS was identified in 321 (16%). Provider recognition was present in 97 (30%) cases and occurred more often in subjects who were older, had worse oxygenation deficits, or were bone marrow transplant recipients. Recognition rates increased each studied year. LPV practices did not differ based on provider recognition; however, subjects who received it were more likely to experience permissive hypoxemia and adherence to extrapulmonary recommendations. Ultimately, there was no differences in outcomes between the provider recognition and non-provider recognition groups. Three themes emerged from the QDA: (1) pediatric ARDS presents within a complex, multidimensional context, with potentially competing organ system failures; (2) similar to historical conceptualizations, pediatric ARDS was often considered a visual diagnosis, with measures of oxygenation unreferenced; and (3) emphasis was placed on non-evidence-based interventions, such as pulmonary clearance techniques, rather than on consensus recommendations. CONCLUSIONS: Among mechanically ventilated children, pediatric ARDS was common but recognized in a minority of cases. Potential opportunities, such as an opt-out approach to LPV, may exist for improved dissemination and implementation of recommended best practices. [ABSTRACT FROM AUTHOR]

Background: Patients with ARDS due to COVID-19 may require tracheostomy and transfer to a weaning center. To date, data on the outcome of these patients are scarce. The objectives of this study were to determine the factors associated with time to decannulation and limb-muscle strength recovery. Methods: This was an observational retrospective study of subjects with COVID-19-related ARDS requiring tracheostomy after prolonged ventilation, who were subsequently transferred to a weaning center from April 4, 2020-May 30, 2020. Results: Forty-three subjects were included. Median age (interquartile range) was 61 (48-66) y; 81% were men, and median body mass index (BMI) was 30 (26-35) kg/m2. Tracheostomy was performed after a median of 19 (12-27) d of mechanical ventilation, and the median ICU length of stay prior to transfer to the weaning center was 30 (21-46) d. On admission to the weaning center, the median Medical Research Council (MRC) score was 36 (27-44). Time to decannulation was 9 (7-18) d after admission to the weaning center. The only factor independently associated with early decannulation was the MRC score on admission to the weaning center (odds ratio 1.16 [95% CI 1.06-1.31], P = .005). Two factors were independently associated with MRC gain ≥ 10: BMI (odds ratio 0.88 [95% CI 0.76-0.99], P = .045) and MRC on admission (odds ratio 0.91 [95% CI 0.82-0.98], P = .03. Three months after admission to the weaning center, 40 subjects (93%) were weaned from mechanical ventilation and 36 (84%) had returned home. Conclusions: MRC score at weaning center admission predicted both early decannulation and limb-muscle strength recovery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pediatric patients with ARDS will on occasion need venovenous extracorporeal membrane oxygenation (VV-ECMO) for organ support. As these patients recover, they may benefit from lung recruitment maneuvers including flexible bronchoscopy (FB). The objective of this study was to assess the clinical course of patients who underwent FB while on VV-ECMO for ARDS. METHODS: This was a secondary analysis of a retrospective multi-center cohort at 10 United States pediatric academic quaternary care centers. Data were collected on 204 subjects age 14 d-18 y on VV-ECMO. RESULTS: 271 FBs were performed on 129 (63%) subjects. Pre-FB tidal volume was 1.8 mL/kg compared to 2.22 mL/kg following FB (P = .007). Dynamic compliance also improved from pre-FB to post-FB (2.23 vs 3.04 mL/cm H2O, P = .005). There was a low incidence of complications following FB (3.1%). Subjects in the FB group had fewer ECMO-free days (EFDs) (17.9 vs 22.1 d, P < .001), fewer ventilator-free days (VFDs) (40.0 vs 46.5 d, P = .001), and longer ICU length of stay (LOS) (18 vs 32 d, P < .001). Subjects in the early versus late FB group had more EFDs (19.4 vs 15.2 d, P = .003), more VFDs (43.0 vs 34.0 d, P = .004), and shorter ICU LOS (27.5 vs 35.5 d, P = .045). Mortality in the subjects who had at least one FB was 27.1% compared to 40% in the subjects who did not have a FB while on VV-ECMO (P = .057). CONCLUSIONS: FB can be performed on patients while anticoagulated on VV-ECMO with a low incidence of complications. FB may be beneficial especially when performed early in the course of VV-ECMO. [ABSTRACT FROM AUTHOR]

Acute respiratory failure with inadequate oxygenation and/or ventilation is a common reason for ICU admission in children and adults. Despite the morbidity and mortality associated with acute respiratory failure, few proven treatment options exist beyond invasive ventilation. Attempts to develop intravascular respiratory assist catheters capable of providing clinically important gas exchange have had limited success. Only one device, the IVOX catheter, was tested in human clinical trials before development was halted without FDA approval. Overcoming the technical challenges associated with providing safe and effective gas exchange within the confines of the intravascular space remains a daunting task for physicians and engineers. It requires a detailed understanding of the fundamentals of gas transport and respiratory physiology to optimize the design for a successful device. This article reviews the potential benefits of such respiratory assist catheters, considerations for device design, previous attempts at intravascular gas exchange, and the motivation for continued development efforts. [ABSTRACT FROM AUTHOR]

BACKGROUND: Extubation early in the postoperative period is beneficial to the recovery and rehabilitation of patients. This study compared the postoperative extubation failure rates among infants who received postextubation respiratory support by either bi-level positive airway pressure (BPAP) or nasal CPAP following cardiac surgery. METHODS: This was a single-center randomized controlled trial registered at the Chinese Clinical Trial Registry (number ChiCTR2000041453) and was conducted between January 2020 and March 2021. Ventilated infants who underwent cardiac surgery were randomized to either a BPAP or a nasal CPAP group for ventilatory support following extubation. The primary outcome measure was the extubation failure rate within 48 h. RESULTS: The analyses included 186 subjects. Treatment failure necessitating re-intubation was noted in 14 of the 93 infants (15%) in the BPAP group and in 11 of the 93 infants (12%) in the nasal CPAP group (P = .52). Moreover, there were no statistically significant differences between the 2 groups regarding the duration of noninvasive ventilation (P = .54), total enteral feeding time (P = .59), or complications (P = .85). We found that both the BPAP group and the nasal CPAP group showed significantly improved oxygenation and relief of respiratory distress after treatment. However, the ... level within 24 h was significantly lower in the BPAP group (P = .001) than in the CPAP group. Additionally, the ... in the BPAP group was significantly higher than in the nasal CPAP group at 6 h, 12 h, and 24 h after treatment (P < .001). CONCLUSIONS: The introduction of BPAP for postextubation respiratory support was not inferior to nasal CPAP in infants after cardiac surgery. Moreover, BPAP was shown to be superior to nasal CPAP in improving oxygenation and carbon dioxide clearance. [ABSTRACT FROM AUTHOR]

The article comments on a study on the usefulness of inhaled sedation in patients with severe acute respiratory distress syndrome (ARDS) due to COVID-19. It points out the limited application of volatile anesthetics for surgical anesthesia due to incompatibility with modern intensive care unit (ICU) ventilators and lack of familiarity. It suggests the potential role of sedative in minimizing harm from lung injury aside from facilitating mechanical ventilation.

This commentary refers to the article "Heterogeneity of Ventilation/Perfusion Mismatch at Different Levels of PEEP and in Mechanical Phenotypes of COVID-19 ARDS," by G. Scaramuzzo, D. S. Karbing, A. Foragnolo and colleagues, that was published within the issue. Topics discussed include acute respiratory distress syndrome (ARDS), positive end-expiratory pressure, and oxygenation-based definition and severity assignment of ARDS.

An introduction to articles in the issue is presented on topics including a barrier enclosure for actively removing aerosols during treatment of patients with contagious respiratory illnesses, parameters associated with a successful extubation readiness test (ERT) in children with congenital heart disease, and a retrospective review of tracheostomy performed in subjects who required guardian approval for the procedure.

BACKGROUND: The impact of mechanical ventilation parameters and management on outcomes of patients with coronavirus disease 2019 (COVID-19) ARDS is unclear. METHODS: This multicenter observational study enrolled consecutive mechanically ventilated patients with COVID-19 ARDS admitted to one of 7 Korean ICUs between February 1, 2020-February 28, 2021. Patients who were age < 17 y or had missing ventilation parameters for the first 4 d of mechanical ventilation were excluded. Multivariate logistic regression was used to identify which strategies or ventilation parameters that were independently associated with ICU mortality. RESULTS: Overall, 129 subjects (males, 60%) with a median (interquartile range) age of 69 (62-78) y were included. Neuromuscular blocker (NMB) use and prone positioning were applied to 76% and 16% of subjects, respectively. The ICU mortality rate was 37%. In the multivariate analysis, higher dynamic driving pressure (DP) values during the first 4 d of mechanical ventilation were associated with increased mortality (adjusted odds ratio 1.16 [95% CI 1.00-1.33], P = .046). NMB use was associated with decreased mortality (adjusted odds ratio 0.27 [95% CI 0.09-0.81], P = .02). The median tidal volume values during the first 4 d of mechanical ventilation and the ICU mortality rate were significantly lower in the NMB group than in the no NMB group. However, subjects who received NMB for ≥ 6 d (vs < 6 d) had higher ICU mortality rate. CONCLUSIONS: In subjects with COVID-19 ARDS receiving mechanical ventilation, DP during the first 4 d of mechanical ventilation was independently associated with mortality. The short-term use of NMB facilitated lungprotective ventilation and was independently associated with decreased mortality. [ABSTRACT FROM AUTHOR]

BACKGROUND: Prone positioning is used for patients with ARDS undergoing invasive mechanical ventilation; its effectiveness in nonventilated awake patients is unclear. We aimed to evaluate the effectiveness of the prone maneuver in decreasing the risk of intubation and increasing the odds of favorable events. METHODS: We prospectively evaluated 66 subjects with COVID-19-related moderate ARDS who were admitted to the ICU; treated with high-flow nasal cannula, noninvasive ventilation, a reservoir mask, or a nasal cannula; and subjected to awake prone maneuvers from March 1, 2020-August 30, 2020. The following factors were recorded at ICU admission: age, sex, prior illness, simplified acute physiology score 3, body mass index, and changes in gas exchange after and before prone positioning. Subjects were divided into a group of responders and nonresponders according to a 20% increase in the ... ratio before and after the maneuver. The need for intubation within 48 h of the start of the maneuver was also evaluated. We also analyzed the differences in mortality, ICU length of stay, hospital length of stay, and duration of mechanical ventilation. A generalized estimating equation model was applied to preprone and postprone means. To control for confounding factors, multivariate Poisson regression was applied. RESULTS: Forty-one subjects age 54.1 y 6 12.9 were enrolled. Responders showed increased ... (P < .001), ... (P < .001), and ... ratios (P < .001) with the maneuver and reduced breathing frequency. Responders had shorter lengths of stay in the ICU (P < .001) and hospital (P < .003), lower intubation rates at 48 h (P < .012), fewer days of ventilation (P < .02), and lower mortality (P < .001). Subjects who responded to the maneuver had a 54% reduction in the risk of ventilation and prolonged stay in the ICU. CONCLUSIONS: Among the responders to prone positioning, there were fewer deaths, shorter duration of mechanical ventilation, shorter ICU length of stay, and shorter hospital length of stay. [ABSTRACT FROM AUTHOR]

BACKGROUND: As lung ultrasound (LUS) has emerged as a diagnostic tool in patients with COVID-19, we sought to investigate the association between LUS findings and the composite inhospital outcome of ARDS incidence, ICU admission, and all-cause mortality. METHODS: In this prospective, multi-center, observational study, adults with laboratory-confirmed SARS-CoV-2 infection were enrolled from non-ICU in-patient units. Subjects underwent an LUS evaluating a total of 8 zones. Images were analyzed off-line, blinded to clinical variables and outcomes. A LUS score was developed to integrate LUS findings: ≥ 3 B-lines corresponded to a score of 1, confluent B-lines to a score of 2, and subpleural or lobar consolidation to a score of 3. The total LUS score ranged from 0-24 per subject. RESULTS: Among 215 enrolled subjects, 168 with LUS data and no current signs of ARDS or ICU admission (mean age 59 y, 56% male) were included. One hundred thirty-six (81%) subjects had pathologic LUS findings in ≥ 1 zone (≥ 3 B-lines, confluent Blines, or consolidations). Markers of disease severity at baseline were higher in subjects with the composite outcome (n = 31, 18%), including higher median C-reactive protein (90 mg/L vs 55, P < .001) and procalcitonin levels (0.35 µg/L vs 0.13, P = .033) and higher supplemental oxygen requirements (median 4 L/min vs 2, P = .001). However, LUS findings and score did not differ significantly between subjects with the composite outcome and those without, and were not associated with outcomes in unadjusted and adjusted logistic regression analyses. CONCLUSIONS: Pathologic findings on LUS were common a median of 3 d after admission in this cohort of non-ICU hospitalized subjects with COVID-19 and did not differ among subjects who experienced the composite outcome of incident ARDS, ICU admission, and all-cause mortality compared to subjects who did not. These findings should be confirmed in future investigations. The study is registered at Clinicaltrials.gov (NCT04377035). [ABSTRACT FROM AUTHOR]

The article discusses a study which compared the performance of double-trunk mask (DTM) and non-rebreather mask (NRM) on arterial blood gases in hypoxemic subjects with COVID-19 presenting to emergency department (ED) with acute respiratory distress. Topics covered include the inclusion criterion and sociodemographic description of study participants, the improvement in blood oxygenation with DTM compared to NRM, and the strengths and limitations of the study.

BACKGROUND: The SARS-CoV-2 pandemic increased the number of patients needing invasive mechanical ventilation, either through an endotracheal tube or through a tracheostomy. Tracheomalacia is a rare but potentially severe complication of mechanical ventilation, which can significantly complicate the weaning process. The aim of this study was to describe the strategies of airway management in mechanically ventilated patients with respiratory failure due to SARS-CoV-2, the incidence of severe tracheomalacia, and investigate the factors associated with its occurrence. METHODS: This retrospective, single-center study was performed in an Italian teaching hospital. All adult subjects admitted to the ICU between February 24, 2020, and June 30, 2020, treated with invasive mechanical ventilation for respiratory failure caused by SARS-CoV-2 were included. Clinical data were collected on the day of ICU admission, whereas information regarding airway management was collected daily. RESULTS: A total of 151 subjects were included in the study. On admission, ARDS severity was mild in 21%, moderate in 62%, and severe in 17% of the cases, with an overall mortality of 40%. A tracheostomy was performed in 73 (48%), open surgical technique in 54 (74%), and percutaneous Ciaglia technique in 19 (26%). Subjects who had a tracheostomy performed had, compared to the other subjects, a longer duration of mechanical ventilation and longer ICU and hospital stay. Tracheomalacia was diagnosed in 8 (5%). The factors associated with tracheomalacia were female sex, obesity, and tracheostomy. CONCLUSIONS: In our population, approximately 50% of subjects with ARDS due to SARS-CoV-2 were tracheostomized. Tracheostomized subjects had a longer ICU and hospital stay. In our population, 5% were diagnosed with tracheomalacia. This percentage is 10 times higher than what is reported in available literature, and the underlying mechanisms are not fully understood. [ABSTRACT FROM AUTHOR]

BACKGROUND: Results of recent studies suggest that the incidence and mortality of ARDS may be higher than previously thought in pediatric trauma patients. We conducted a systematic review of the literature on incidence, risk factors, prognostic factors, and outcomes of ARDS after pediatric trauma in the ICU. METHODS: Medical literature databases were searched up to April 2020. Guidelines for reporting systematic reviews and meta-analyses were followed. Articles that reported quantitative data with regard to the incidence, risk factors, prognostic factors, mortality, or other outcomes for ARDS in subjects with pediatric trauma admitted to the ICU were included. Two authors independently screened and assessed eligibility of all identified studies, collected data, and assessed the methodological quality of selected studies. Data extraction was performed by using a standardized data extraction sheet. Quality assessment was performed by using the Newcastle-Ottawa scale for cohort studies. A meta-analysis was not performed because the studies used overlapping cohorts or different ARDS criteria. RESULTS: Nine studies were included. The incidence was reported in 4 studies, risk factors in 1, mortality in 7, and other outcomes in 2. The largest cohort included 148,749 subjects from a national trauma database. The ARDS incidence was 1.8%--7.6% when using adult ARDS criteria, with 1.8% in the largest cohort, and 4.2% when using pediatric ARDS criteria. Mortality was 7.6%--22.9% when using adult ARDS criteria and 11.1%--34.0% when using the pediatric ARDS criteria. Identified risk factors included mechanism of injury, higher injury severity scores, abnormal breathing frequencies, and lower Glasgow coma scale scores at hospital presentation. ARDS was associated with a longer duration of mechanical ventilation, longer ICU and hospital length of stay, and a higher likelihood of requiring post-discharge care. CONCLUSIONS: The ARDS incidence of 4.2% in the subjects with pediatric trauma in the ICU was comparable with 3.2% in the general pediatric ICU population; however, mortality associated with trauma-associated ARDS was higher and more commonly due to multi-system organ failure rather than hypoxemia. [ABSTRACT FROM AUTHOR]

BACKGROUND: The novel coronavirus-associated ARDS (COVID-19 ARDS) often requires invasive mechanical ventilation. A spectrum of atypical ARDS with different phenotypes (high vs low static compliance) has been hypothesized in COVID-19. METHODS: We conducted a retrospective analysis to identify respiratory mechanics in COVID-19 ARDS. Berlin definition was used to categorize severity of ARDS. Correlational analysis using t test, chi-square test, ANOVA test, and Pearson correlation was used to identify relationship between subject variables and respiratory mechanics. The primary outcome was duration of mechanical ventilation. Secondary outcomes were correlation between fluid status, C- reactive protein, PEEP, and D-dimer with respiratory and ventilatory parameters. RESULTS: Median age in our cohort was 60.5 y with predominantly male subjects. Up to 53% subjects were classified as severe ARDS (median PaO2/FIO2 = 86) with predominantly low static compliance (median Cst- 25.5 mL/cm H2O). The overall mortality in our cohort was 61%. The total duration of mechanical ventilation was 35 d in survivors and 14 d in nonsurvivors. High PEEP (r = 0.45, P < .001) and D-dimer > 2,000 ng/dL (P = .009) correlated with significant increase in physiologic dead space without significant correlation with PaO2/FIO2. Higher net fluid balance was inversely related to static compliance (r = -0.24, P = .045), and elevation in C- reactive protein was inversely related to PaO2/FIO2 (r = -0.32, P = .02). CONCLUSIONS: In our cohort of mechanically ventilated COVID-19 ARDS subjects, high PEEP and D-dimer were associated with increase in physiologic dead space without significant effect on oxygenation, raising the question of potential microvascular dysfunction. [ABSTRACT FROM AUTHOR]