May noninvasive mechanical ventilation and/ or continuous positive airway pressure increase the bronchoalveolar lavage salvage in patients with pulmonary diseases? Randomized clinical trial - Study protocol

PURPOSE

Bronchoalveolar lavage (BAL) procedure is a useful tool in the diagnosis of patients with interstitial lung disease (ILD) and is helpful in clinical research of chronic obstructive pulmonary disease (COPD) patients. Still little is known about predictors of poor BAL salvage. The trial aims to find the most efficient way to improve BAL recovery.

MATERIAL AND METHODS

Our study is a prospective, multicenter, international, two-arm randomized controlled trial. We aim to obtain BAL samples from a total number of 300 patients: 150 with ILD and 150 with COPD to achieve a statistical power of 80 ​%. Patients with initial BAL salvage <60 ​% will be randomized into the non-invasive ventilation (NIV) or continuous positive airway pressure (CPAP) arm. The NIV and CPAP will be set according to the study protocol. The influence on BAL salvage will be assessed in terms of BAL volume and content. Multivariable analysis of the additional test results to determine predictors for low BAL recovery will be conducted. In a study subgroup of approximately 20 patients per specific disease, a metabolomic assessment of exhaled air condensate will be performed. All procedures will be assessed in terms of the patient's safety. The trial was registered on clinicaltrials.gov (ID# NCT05631132). Interested experienced centers are invited to join the research group by writing to the corresponding author.

CONCLUSION

The results of our prospective study will address the currently unsolved problem of how to increase BAL salvage in patients with pulmonary diseases without increasing the risk of respiratory failure exacerbation.

Role of respiratory characteristics in treatment adherence with noninvasive home mechanical ventilation in myotonic dystrophy type 1, a retrospective study

Chronic respiratory insufficiency is common in patients with myotonic dystrophy type 1 (DM1) and can be treated with noninvasive home mechanical ventilation (HMV). HMV is not always tolerated well resulting in low treatment adherence. We aimed to analyze if baseline respiratory characteristics such as pulmonary function, level of pCO2 and presence of sleep apnea are associated with HMV treatment adherence in DM1 patients. Pulmonary function testing, polysomnography and blood gas measurement data of DM1 patients were retrospectively collected. Initiation of HMV and treatment adherence after one year was documented. Patients with low treatment adherence (average daily use of HMV <5 h) were grouped with patients that discontinued HMV and compared with patients with high treatment adherence (average daily use of HMV >5 h). HMV was initiated in 101 patients. After one year, 58 patients had low treatment adherence. There were no differences between the low and high treatment adherence group regarding the respiratory characteristics. None of the included predictors (gender, age, body mass index, cytosine-thymine-guanine repeat length, FVC, daytime pCO2, bicarbonate, nighttime pCO2, nighttime base excess, apnea-hypopnea index and mean saturation during sleep) was able to significantly predict high treatment adherence. In conclusion, the respiratory characteristics are not associated with treatment adherence with HMV in DM1 patients and cannot be used to identify patients at risk for low HMV treatment adherence.

The use of a noninvasive positive pressure system to facilitate tracheal intubation in a difficult pediatric airway: a case report

Patients with burns to the head and neck may be difficult to intubate or ventilate via facemask. Furthermore, post-burn scarring and microstomia may reduce the success of rescue supraglottic airway placement. While awake tracheal intubation using a flexible intubation scope is considered the optimal technique for these patients, it may not always be feasible in the pediatric population. We report a case of successful management of a difficult airway in a child with extensive post-burn head and neck deformity using a noninvasive positive pressure system to aid with inhalational induction and deep sedation during intubation using a flexible scope.

Helmet Continuous Positive Airway Pressure in the Emergency Department: A Practical Guide

Helmet continuous positive airway pressure is a simple, noninvasive respiratory support strategy to treat several forms of acute respiratory failure, such as cardiogenic pulmonary edema and pneumonia. Recently, it has been largely used worldwide during the COVID-19 pandemic. Given the increased use of helmet continuous positive airway pressure in the emergency department, we aimed to provide an updated practical guide for nurses and clinicians based on the latest available evidence. We focus our attention on how to set the respiratory circuit. Moreover, we discuss the interactions between flow generators, filters, and positive end-expiratory pressure valves and the consequences regarding the delivered gas flow, fraction of inspired oxygen, positive end-expiratory pressure, and noise level.

The use of non-invasive respiratory assistance to facilitate bronchofiberoscopy performance in patients with hypoxemic (type one) respiratory failure - Study protocol

PURPOSE

Bronchofiberoscopy (FOB) is a procedure routinely performed for: lung cancer, obstruction, interstitial diseases, foreign bodies' removal, airway clearance, and hemoptysis. It causes acute airway narrowing leading to respiratory and cardiovascular stress. Due to increasing number of ill patients with respiratory failure (RF), conventional oxygen therapy (COT) is frequently insufficient to assure accurate oxygenation and prevent RF in patients requiring FOB. In this clinical scenario, patients may be intubated and supported with invasive mechanical ventilation (IMV) with the specific aim of allowing a safe FOB. However, this invasive strategy is associated with an increased risk of IMV-associated complications.

MATERIALS AND METHODS

Our study is a planned prospective multicenter three-arm randomized controlled trial (RCT). The target number of 300 patients was calculated based on the intubation risk in RF patients, which is 0.2-2%. The patients will be assigned to each arm based on Horowitz index. In each arm, the patients will be randomly assigned to one out of two dedicated respiratory support methods in each group i.e. COT/high flow nasal cannula (HFNC), HFNC/non-invasive ventilation (NIV) and NIV/IMV. In the manuscript the current state of art in the area of respiratory support is discussed. We have underlined knowledge gaps in medical evidence which we are planning to reveal with our results.

RESULTS

The results of our study are clinically crucial, because they address current gaps concerning COT/HFNC/NIV/IMV.

CONCLUSION

The expected findings of this study would allow for careful selection of respiratory support method to safely perform FOB in patients with hypoxemic RF.

Outpatient Utilization of the RAM Cannula for Nasal Noninvasive Ventilation in Children

Background

The RAM cannula® consists of nasal prongs that can be used to administer oxygen, continuous, and bilevel positive airway pressure therapies. Studies have reported the efficacy and utility of the RAM cannula in inpatients requiring noninvasive ventilation (NIV); however, there is limited literature on the use of the RAM cannula to provide NIV in the outpatient setting.

Objectives

This study aimed to describe the clinical features and outcomes of children who used NIV via RAM cannula in the outpatient setting.

Design

Retrospective review.

Methods

We conducted a retrospective review of children treated with outpatient NIV via RAM cannula at our institution between January 2010 and March 2023. The analyzed data included age, diagnoses, indications for NIV, duration of RAM cannula use, complications, and outcomes at 6 months.

Results

We identified 20 patients who used outpatient NIV via RAM cannula during the study period. The median age at initiation of NIV via RAM cannula was 5.8 months (IQR 2.4-9.9 months). Indications for NIV included sleep-related hypoventilation (15%), restrictive lung disease (25%), obstructive sleep apnea (45%), and chronic respiratory failure (50%), with 6 patients having ⩾2 indications for NIV. RAM cannula was utilized for inability to tolerate conventional NIV interfaces (80%), to alleviate dyspnea (60%), and to avoid tracheostomy (55%). Patients used NIV via RAM cannula for a median duration of 7.7 months (IQR 3.7-20.6 months). Patient outcomes included ongoing usage of RAM cannula (55%), changing to conventional NIV interfaces (15%) or oxygen (10%), weaning off respiratory support (5%), and death (15%). There were no complications related to using the RAM cannula.

Conclusion

Our study demonstrates the utility of outpatient NIV via RAM cannula in children with a variety of diagnoses until clinical improvement or tolerance of conventional interfaces, and for avoidance of tracheostomy.

A pragmatic, open-label, multi-center, randomized controlled clinical trial on the rotational use of interfaces vs standard of care in patients treated with noninvasive positive pressure ventilation for acute hypercapnic respiratory failure: the ROTAtional-USE of interface STUDY (ROTA-USE STUDY)

BACKGROUND

In the last decades, noninvasive ventilation (NIV) has been increasingly used to support patients with hypercapnic and hypoxemic acute respiratory failure. Pressure ulcers are a frequently observed NIV-related adverse effect, directly related to interface type and exposure time. Switching to a different interface has been proposed as a solution to improve patient comfort. However, large studies investigating the benefit of this strategy are not available. Thus, the aim of the ROTAtional-USE of interface STUDY (ROTA-USE STUDY) is to investigate whether a protocolized rotational use of interfaces during NIV is effective in reducing the incidence of pressure ulcers.

METHODS

The ROTA-USE STUDY is a pragmatic, parallel arm, open-label, multicenter, spontaneous, non-profit, randomized controlled trial requiring non-significant risk medical devices, with the aim to determine whether a rotational strategy of NIV interfaces is associated with a lower incidence of pressure ulcers compared to the standard of care. In the intervention group, NIV mask will be randomly chosen and rotated every 6 h. In the control group, mask will be chosen according to the standard of care of the participating centers and changed in case of discomfort or in the presence of new pressure sores. In both groups, the skin underneath the mask will be inspected every 12 h for any possible damage by blinded assessors. The primary outcome is the proportion of patients developing new pressure sores at 36 h from randomization. The secondary outcomes are (i) onset of pressure sores measured at different time points, i.e., 12, 24, 36, 48, 60, 72, 84, and 96 h; (ii) number and stage of pressure sores and comfort measured at 12, 24, 36, 48, 60, 72, 84, and 96 h; and (iii) the economic impact of the protocolized rotational use of interfaces. A sample size of 239 subjects per group (intervention and control) is estimated to detect a 10% absolute difference in the proportion of patients developing pressure sores at 36 h.

DISCUSSION

The development of pressure ulcers is a common side effect of NIV that negatively affects the patients' comfort and tolerance, often leading to NIV failure and adverse outcomes. The ROTA-USE STUDY will determine whether a protocolized rotational approach can reduce the incidence, number, and severity of pressure ulcers in NIV-treated patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05513508. Registered on August 24, 2022.

Is disposable continuous positive airway pressure system effective for the management of acute hypercapnic respiratory failure?

AIM

This study aimed to investigate the effectiveness of disposable continuous positive airway pressure (DCPAP) system in decreasing the partial pressure of carbon dioxide (PaCO2) levels in patients with acute hypercapnic respiratory failure (AHRF).

MATERIAL AND METHODS

This retrospective observational study included patients treated in the emergency department (ED) with respiratory distress and PaCO2 > 45 mmHg. Patients were divided into two groups (DCPAP and non-DCPAP), depending on the treatment received to treat AHRF. The difference between the baseline PaCO2 levels in the first blood gas obtained from patients at the time of admission and the follow-up blood gas after treatment. Then, the calculated PaCO2 decrease was divided by the time elapsed to obtain the rate of decrease in PaCO2 levels in mmHg/min. The statistical analyses were performed using SPSS version 18.0 software. A p value of < 0.05 was considered statistically significant.

RESULTS

A total of 61 patients were included in the study, 31 patients in the DCPAP group and 30 patients in the non-DCPAP group. The mean age of the patients was 74.03 ± 10.04, and the male/female was 23/38. The study demonstrated a statistically significant difference between the DCPAP and non-DCPAP groups in terms of PaCO2 decreasing rate, and it was found to be twice higher in the DCPAP group (0.11 ± 0.07 mmHg/min) than in the non-DCPAP group (0.05 ± 0.06 mmHg/min).

CONCLUSION

The study demonstrated that the treatment of AHRF patients with a DCPAP provides a faster decrease in PaCO2 levels in hypercapnic patients compared to standard medical therapy alone.

Analysis of shared cognitive tasks in the application of non-invasive ventilation to patients with COPD exacerbation

Interprofessional teamwork plays a key role in the uptake of evidence-based interventions, such as noninvasive ventilation (NIV) for patients with exacerbated Chronic Obstructive Pulmonary Disease (COPD). We aimed to identify the shared cognitive tasks in interprofessional teams using NIV for patients with COPD exacerbation. We used a cognitive task analysis approach (CTA) to engage nurses, rapid response team members, respiratory therapists, and physicians involved in the use of NIV to treat patients with COPD exacerbation. Clinicians participated in a semi-structured interview (n = 21) that elicited cognitions needed to treat COPD exacerbation. Three shared cognitive tasks were identified: Complete a thorough assessment, Formulate a care plan, and Continuously monitor patient status. Findings attest to the importance of having access to up-to-date information and expertise necessary to make accurate clinical inferences for patient assessment. Shared understanding of the formulated care plan among all members of the care team was important to its execution. Continuous monitoring was crucial; however, this cognitive task relied on patient assessment skills and ongoing collaboration within the clinical care team. Application of NIV for patients with COPD exacerbation may require enhancing collaboration through nontechnical skills and interprofessional training.

Mechanical power normalized to aerated lung predicts noninvasive ventilation failure and death and contributes to the benefits of proning in COVID-19 hypoxemic respiratory failure

Background

Concern exists that noninvasive ventilation (NIV) may promote ventilation-induced lung injury(VILI) and worsen outcome in acute hypoxemic respiratory failure (AHRF). Different individual ventilatory variables have been proposed to predict clinical outcomes, with inconsistent results.Mechanical power (MP), a measure of the energy transfer rate from the ventilator to the respiratory system during mechanical ventilation, might provide solutions for this issue in the framework of predictive, preventive and personalized medicine (PPPM). We explored (1) the impact of ventilator-delivered MP normalized to well-aerated lung (MP_WAL) on physio-anatomical and clinical responses to NIV in COVID-19-related AHRF and (2) the effect of prone position(PP) on MP_WAL.

Methods

We analyzed 216 noninvasively ventilated COVID-19 patients (108 patients receiving PP + NIV and 108 propensity score-matched patients receiving supine NIV) with moderate-to-severe(paO2/FiO2 ratio < 200) AHRF enrolled in the PRO-NIV controlled non-randomized study (ISRCTN23016116).Quantification of differentially aerated lung volumes by lung ultrasonography (LUS) was validated against CT scans. Respiratory parameters were hourly recorded, ABG were performed 1 h after each postural change. Time-weighed average values of ventilatory variables, including MP_WAL, and gas exchange parameters (paO2/FiO2 ratio, dead space indices) were calculated for each ventilatory session. LUS and circulating biomarkers were assessed daily.

Results

Compared with supine position, PP was associated with a 34% MP_WAL reduction, attributable largely to an absolute MP reduction and secondly to an enhanced lung reaeration.Patients receiving a high MP_WAL during the 1^st 24 h of NIV [MP_WAL(day 1)] had higher 28-d NIV failure (HR = 4.33,95%CI:3.09 - 5.98) and death (HR = 5.17,95%CI: 3.01 - 7.35) risks than those receiving a low MP_WAL(day 1).In Cox multivariate analyses, MP_WAL(day 1) remained independently associated with 28-d NIV failure (HR = 1.68,95%CI:1.15-2.41) and death (HR = 1.69,95%CI:1.22-2.32).MP_WAL(day 1) outperformed other power measures and ventilatory variables as predictor of 28-d NIV failure (AUROC = 0.89;95%CI:0.85-0.93) and death (AUROC = 0.89;95%CI:0.85-0.94).MP_WAL(day 1) predicted also gas exchange, ultrasonographic and inflammatory biomarker responses, as markers of VILI, on linear multivariate analysis.

Conclusions

In the framework of PPPM, early bedside MP_WAL calculation may provide added value to predict response to NIV and guide subsequent therapeutic choices i.e. prone position adoption during NIV or upgrading to invasive ventilation, to reduce hazardous MP_WAL delivery, prevent VILI progression and improve clinical outcomes in COVID-19-related AHRF.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-023-00325-5.

Developing a Respiratory Quality Improvement Program to Prevent and Treat Bronchopulmonary Dysplasia in the Neonatal Intensive Care Unit

Improvements in respiratory care have resulted in improved outcomes for preterm infants over the past three decades. To target the multifactorial nature of neonatal lung diseases, neonatal intensive care units (NICUs) should consider developing comprehensive respiratory quality improvement programs that address all drivers of neonatal respiratory disease. This article presents a potential framework for developing a quality improvement program to prevent bronchopulmonary dysplasia in the NICU. Drawing on available research and quality improvement reports, the authors discuss key components, measures, drivers, and interventions that should be considered when building a respiratory quality improvement program devoted to preventing and treating bronchopulmonary dysplasia.

Long-term outcome of COVID-19 patients treated with helmet noninvasive ventilation vs. high-flow nasal oxygen: a randomized trial

BACKGROUND

Long-term outcomes of patients treated with helmet noninvasive ventilation (NIV) are unknown: safety concerns regarding the risk of patient self-inflicted lung injury and delayed intubation exist when NIV is applied in hypoxemic patients. We assessed the 6-month outcome of patients who received helmet NIV or high-flow nasal oxygen for COVID-19 hypoxemic respiratory failure.

METHODS

In this prespecified analysis of a randomized trial of helmet NIV versus high-flow nasal oxygen (HENIVOT), clinical status, physical performance (6-min-walking-test and 30-s chair stand test), respiratory function and quality of life (EuroQoL five dimensions five levels questionnaire, EuroQoL VAS, SF36 and Post-Traumatic Stress Disorder Checklist for the DSM) were evaluated 6 months after the enrollment.

RESULTS

Among 80 patients who were alive, 71 (89%) completed the follow-up: 35 had received helmet NIV, 36 high-flow oxygen. There was no inter-group difference in any item concerning vital signs (N = 4), physical performance (N = 18), respiratory function (N = 27), quality of life (N = 21) and laboratory tests (N = 15). Arthralgia was significantly lower in the helmet group (16% vs. 55%, p = 0.002). Fifty-two percent of patients in helmet group vs. 63% of patients in high-flow group had diffusing capacity of the lungs for carbon monoxide < 80% of predicted (p = 0.44); 13% vs. 22% had forced vital capacity < 80% of predicted (p = 0.51). Both groups reported similar degree of pain (p = 0.81) and anxiety (p = 0.81) at the EQ-5D-5L test; the EQ-VAS score was similar in the two groups (p = 0.27). Compared to patients who successfully avoided invasive mechanical ventilation (54/71, 76%), intubated patients (17/71, 24%) had significantly worse pulmonary function (median diffusing capacity of the lungs for carbon monoxide 66% [Interquartile range: 47-77] of predicted vs. 80% [71-88], p = 0.005) and decreased quality of life (EQ-VAS: 70 [53-70] vs. 80 [70-83], p = 0.01).

CONCLUSIONS

In patients with COVID-19 hypoxemic respiratory failure, treatment with helmet NIV or high-flow oxygen yielded similar quality of life and functional outcome at 6 months. The need for invasive mechanical ventilation was associated with worse outcomes. These data indicate that helmet NIV, as applied in the HENIVOT trial, can be safely used in hypoxemic patients. Trial registration Registered on clinicaltrials.gov NCT04502576 on August 6, 2020.

Average Volume-assured Pressure Support as Rescue Therapy after CPAP Failure in Pediatric Obstructive Sleep Apnea: A Retrospective Case Series Study

Background

Continuous positive airway pressure (CPAP) is frequently prescribed for patients with residual obstructive sleep apnea (OSA) following adenotonsillectomy.

Objectives

The goal was to examine the efficacy of noninvasive ventilation with average volume-assured pressure support (AVAPS) as a potential option for children with failed CPAP titration.

Methods

In a single-center retrospective study, we included children aged 1-17 years, with polysomnographically confirmed OSA who underwent AVAPS titration following failed CPAP titration. In addition to describing the clinical characteristics of the included patients, we compared polysomnographic parameters before and after AVAPS.

Results

Nine patients met the inclusion criteria; out of them, 8 (89%) were males with an age range of 6.7 ± 3.9 years and a body mass index percentile of 81.0 ± 28.9. Reasons for failed CPAP titration were: 3 (33%) patients due to inability to control apnea-hypopnea index (AHI), 3 (33%) patients due to sleep-related hypoventilation, 2 (22%) patients due to treatment-emergent central sleep apnea, and 1 (11%) patient due to intolerance to CPAP. AVAPS resulted in a greater reduction in AHI than CPAP (reduction following CPAP = 24.6 ± 29.3, reduction following AVAPS = 42.5 ± 37.6, p = 0.008). All patients had resolution of the problems which caused CPAP failure.

Conclusion

In this case a series of children with OSA and with failed CPAP titration, AVAPS resulted in a greater reduction in AHI compared with CPAP as well as resolution of the problems which caused CPAP failure.

Effect of Intensity of Home Noninvasive Ventilation in Individuals With Neuromuscular and Chest Wall Disorders: A Systematic Review and Meta-Analysis of Individual Participant Data

INTRODUCTION

Home noninvasive ventilation (NIV), targeting a reduction of carbon dioxide with a combination of sufficient inspiratory support and backup-rate improves outcomes in patients with chronic obstructive pulmonary disease. The aim of this systematic review with individual participant data (IPD) meta-analysis was to evaluate the effects of intensity of home NIV on respiratory outcomes in individuals with slowly progressive neuromuscular (NMD) or chest-wall disorders (CWD).

METHODS

Controlled, non-controlled and cohort studies indexed between January-2000 and December-2020 were sought from Medline, Embase and the Cochrane Central Register. Outcomes were diurnal PaCO₂, PaO₂, daily NIV usage, and interface type (PROSPERO-CRD 42021245121). NIV intensity was defined according to the Z-score of the product of pressure support (or tidal volume) and backup-rate.

RESULTS

16 eligible studies were identified; we obtained IPD for 7 studies (176 participants: 113-NMD; 63-CWD). The reduction in PaCO₂ was greater with higher baseline PaCO₂. NIV intensity per se was not associated with improved PaCO₂ except in individuals with CWD and the most severe baseline hypercapnia. Similar results were found for PaO₂. Daily NIV usage was associated with improvement in gas exchange but not with NIV intensity. No association between NIV intensity and interface type was found.

CONCLUSION

Following home NIV initiation in NMD or CWD patients, no relationship was observed between NIV intensity and PaCO₂, except in individuals with the most severe CWD. The amount of daily NIV usage, rather than intensity, is key to improving hypoventilation in this population during the first few months after introduction of therapy.

Airway obstruction caused by achalasia: A case report

We report a rare case of airway obstruction caused by megaesophagus associated with achalasia. A 78-year-old man was admitted with post meal dyspnea, decreased consciousness, expiratory and inspiratory wheezing, and respiratory distress. Arterial blood gas analysis showed findings of marked acute respiratory acidosis (pH 7.18, PaCO₂ 75 mmHg, PaO₂ 225 mm Hg, HCO₃^- 22 mmol/L). An emergency laryngoscopy was performed because of a suspected airway obstruction, but no abnormalities were observed from the airway to the glottis. Noninvasive positive pressure ventilation (NPPV) was immediately introduced, and the respiratory rate and breathing pattern was normalized. A chest X-ray showed an enlarged upper mediastinal outline and an ill-defined border of the trachea. A computed tomography (CT) scan showed an enlarged esophagus with a maximum diameter of 9.90 cm, compressing the trachea to the back of the sternal notch. Following removal of the esophageal contents using a nasogastric tube, NPPV was discontinued with no respiratory episodes. After he was stabilized, he was transferred to another hospital for endoscopic myotomy. In a review of the literature, we identified 66 cases of airway obstruction due to achalasia, mainly in older women. None of the patients received NPPV. As a differential diagnosis for acute airway obstruction, achalasia-related airway obstruction should be considered, particularly in older women. Furthermore, since this condition is suspected to involve tracheomalacia, NPPV may be a useful respiratory support therapy.

Importance of proper ventilator support and pulmonary rehabilitation in obese patients with heart failure: Two case reports

BACKGROUND

The optimal treatment for heart failure (HF) is a combination of appropriate medications. Controlling the disease using only medical therapy is difficult in patients with HF, severe hypercapnia, and desaturation. These patients should first receive ventilator support followed by pulmonary rehabilitation (PR).

CASE SUMMARY

We report two cases in which arterial blood gas (ABG) improved and PR was possible with appropriate ventilator support. Two patients with extreme obesity complaining of worsening dyspnea–a 47-year-old woman and a 36-year-old man both diagnosed with HF–were hospitalized because of severe hypercapnia and hypoxia. Despite proper medical treatment, hypercapnia and desaturation resolved in neither case, and both patients were transferred to the rehabilitation department for PR. At the time of the first consultation, the patients were bedridden because of dyspnea. Oxygen demand was successfully reduced once noninvasive ventilation was initiated. As the patients’ dyspnea gradually improved to the point where they could be weaned off the ventilator during the daytime, they started engaging in functional training and aerobic exercise. After 4 mo of follow-up, both patients were able to perform activities of daily living and maintain their lower body weight and normalized ABG levels.

CONCLUSION

Symptoms of patients with obesity and HF may improve once ABG levels are normalized through ventilator support and implementation of PR.

[Modeling the noninvasive bi-level positive airway pressure ventilation therapy system and simulated application]

Without artificial airway though oral, nasal or airway incision, the bi-level positive airway pressure (Bi-PAP) has been widely employed for respiratory patients. In an effort to investigate the therapeutic effects and measures for the respiratory patients under the noninvasive Bi-PAP ventilation, a therapy system model was designed for virtual ventilation experiments. In this system model, it includes a sub-model of noninvasive Bi-PAP respirator, a sub-model of respiratory patient, and a sub-model of the breath circuit and mask. And based on the Matlab Simulink, a simulation platform for the noninvasive Bi-PAP therapy system was developed to conduct the virtual experiments in simulated respiratory patient with no spontaneous breathing (NSB), chronic obstructive pulmonary disease (COPD) and acute respiratory distress syndrome (ARDS). The simulated outputs such as the respiratory flows, pressures, volumes, etc, were collected and compared to the outputs which were obtained in the physical experiments with the active servo lung. By statistically analyzed with SPSS, the results demonstrated that there was no significant difference ( P > 0.1) and was in high similarity ( R > 0.7) between the data collected in simulations and physical experiments. The therapy system model of noninvasive Bi-PAP is probably applied for simulating the practical clinical experiment, and maybe conveniently applied to study the technology of noninvasive Bi-PAP for clinicians.

Mechanical Insufflation-Exsufflation: The Rest of the Story

Mechanical insufflation-exsufflation has been reported to decrease pneumonia rates by about 90% for patients with Duchenne muscular dystrophy now living into their 40s and 50s without tracheotomy tubes. It greatly reduces respiratory complications and hospitalization rates to less than one per 10 patient-years for advanced spinal muscular atrophy type 1, through 25-30 years of age. It is most successful from the point at which small children become able to cooperate with it, generally from 3 to 5 years of age. However, since the 1950s, successful use to extubate and decannulate ventilator "unweanable" patients with little to no measurable vital capacity without resorting to tracheostomy has always been at pressures of 50-60 cm H2O via oronasal interfaces and at 60-70 cm H2O via airway tubes when present. It must usually also be used in conjunction with up to continuous noninvasive positive pressure ventilatory support. Centers that use these effectively have eliminated need to resort to tracheotomies for people with muscular dystrophies and spinal muscular atrophies, including unmedicated patients with spinal muscular atrophy type 1. Barotrauma has been rare despite dependence on it and noninvasive ventilatory support. Despite this, noninvasive respiratory management continues to be widely underutilized.

Delayed mechanical ventilation with prolonged high-flow nasal cannula exposure time as a risk factor for mortality in acute respiratory distress syndrome due to SARS-CoV-2

In a high proportion of patients, infection by COVID-19 progresses to acute respiratory distress syndrome (ARDS), requiring invasive mechanical ventilation (IMV) and admission to an intensive care unit (ICU). Other devices, such as a high-flow nasal cannula (HFNC), have been alternatives to IMV in settings with limited resources. This study evaluates whether HFNC exposure time prior to IMV is associated with mortality. This observational, analytical study was conducted on a historical cohort of adults with ARDS due to SARS-CoV-2 who were exposed to HFNC and subsequently underwent IMV. Univariate and multivariate logistic regression was used to analyze the impact of HFNC exposure time on mortality, controlling for multiple potential confounders. Of 325 patients with ARDS, 41 received treatment with HFNC for more than 48 h before IMV initiation. These patients had a higher mortality rate (43.9% vs. 27.1%, p: 0.027) than those using HFNC < 48 h. Univariate analysis evidenced an association between mortality and HFNC ≥ 48 h (OR 2.16. 95% CI 1.087-4.287. p: 0.028). Such an association persisted in the multivariable analysis (OR 2.21. 95% CI 1.013-4.808. p: 0.046) after controlling for age, sex, comorbidities, basal severity of infection, and complications. This study also identified a significant increase in mortality after 36 h in HFNC (46.3%, p: 0.003). In patients with ARDS due to COVID-19, HFNC exposure ≥ 48 h prior to IMV is a factor associated with mortality after controlling multiple confounders. Physiological mechanisms for such an association are need to be defined.

Long-term outcomes of patients with COVID-19 treated with helmet noninvasive ventilation or usual respiratory support: follow-up study of the Helmet-COVID randomized clinical trial

PURPOSE

To evaluate whether helmet noninvasive ventilation compared to usual respiratory support reduces 180-day mortality and improves health-related quality of life (HRQoL) in patients with acute hypoxemic respiratory failure due to COVID-19 pneumonia.

METHODS

This is a pre-planned follow-up study of the Helmet-COVID trial. In this multicenter, randomized clinical trial, adults with acute hypoxemic respiratory failure (n = 320) due to coronavirus disease 2019 (COVID-19) were randomized to receive helmet noninvasive ventilation or usual respiratory support. The modified intention-to-treat population consisted of all enrolled patients except three who were lost at follow-up. The study outcomes were 180-day mortality, EuroQoL (EQ)-5D-5L index values, and EQ-visual analog scale (EQ-VAS). In the modified intention-to-treat analysis, non-survivors were assigned a value of 0 for EQ-5D-5L and EQ-VAS.

RESULTS

Within 180 days, 63/159 patients (39.6%) died in the helmet noninvasive ventilation group compared to 65/158 patients (41.1%) in the usual respiratory support group (risk difference - 1.5% (95% confidence interval [CI] - 12.3, 9.3, p = 0.78). In the modified intention-to-treat analysis, patients in the helmet noninvasive ventilation and the usual respiratory support groups did not differ in EQ-5D-5L index values (median 0.68 [IQR 0.00, 1.00], compared to 0.67 [IQR 0.00, 1.00], median difference 0.00 [95% CI - 0.32, 0.32; p = 0.91]) or EQ-VAS scores (median 70 [IQR 0, 93], compared to 70 [IQR 0, 90], median difference 0.00 (95% CI - 31.92, 31.92; p = 0.55).

CONCLUSIONS

Helmet noninvasive ventilation did not reduce 180-day mortality or improve HRQoL compared to usual respiratory support among patients with acute hypoxemic respiratory failure due to COVID-19 pneumonia.

Oxygenation thresholds for invasive ventilation in hypoxemic respiratory failure: a target trial emulation in two cohorts

BACKGROUND

The optimal thresholds for the initiation of invasive ventilation in patients with hypoxemic respiratory failure are unknown. Using the saturation-to-inspired oxygen ratio (SF), we compared lower versus higher hypoxemia severity thresholds for initiating invasive ventilation.

METHODS

This target trial emulation included patients from the Medical Information Mart for Intensive Care (MIMIC-IV, 2008-2019) and the Amsterdam University Medical Centers (AmsterdamUMCdb, 2003-2016) databases admitted to intensive care and receiving inspired oxygen fraction ≥ 0.4 via non-rebreather mask, noninvasive ventilation, or high-flow nasal cannula. We compared the effect of using invasive ventilation initiation thresholds of SF < 110, < 98, and < 88 on 28-day mortality. MIMIC-IV was used for the primary analysis and AmsterdamUMCdb for the secondary analysis. We obtained posterior means and 95% credible intervals (CrI) with nonparametric Bayesian G-computation.

RESULTS

We studied 3,357 patients in the primary analysis. For invasive ventilation initiation thresholds SF < 110, SF < 98, and SF < 88, the predicted 28-day probabilities of invasive ventilation were 72%, 47%, and 19%. Predicted 28-day mortality was lowest with threshold SF < 110 (22.2%, CrI 19.2 to 25.0), compared to SF < 98 (absolute risk increase 1.6%, CrI 0.6 to 2.6) or SF < 88 (absolute risk increase 3.5%, CrI 1.4 to 5.4). In the secondary analysis (1,279 patients), the predicted 28-day probability of invasive ventilation was 50% for initiation threshold SF < 110, 28% for SF < 98, and 19% for SF < 88. In contrast with the primary analysis, predicted mortality was highest with threshold SF < 110 (14.6%, CrI 7.7 to 22.3), compared to SF < 98 (absolute risk decrease 0.5%, CrI 0.0 to 0.9) or SF < 88 (absolute risk decrease 1.9%, CrI 0.9 to 2.8).

CONCLUSION

Initiating invasive ventilation at lower hypoxemia severity will increase the rate of invasive ventilation, but this can either increase or decrease the expected mortality, with the direction of effect likely depending on baseline mortality risk and clinical context.

Comparing the effects of continuous positive airway pressure via mask or helmet interface on oxygenation and pulmonary complications after major abdominal surgery: a randomized trial

The risk of pulmonary complications is high after major abdominal surgery but may be reduced by prophylactic postoperative noninvasive ventilation using continuous positive airway pressure (CPAP). This study compared the effects of intermittent mask CPAP (ICPAP) and continuous helmet CPAP (HCPAP) on oxygenation and the risk of pulmonary complications following major abdominal surgery. Patients undergoing open abdominal aortic aneurysm repair or pancreaticoduodenectomy were randomized (1:1) to either postoperative ICPAP or HCPAP. Oxygenation was evaluated as the partial pressure of oxygen in arterial blood fraction of inspired oxygen ratio (PaO₂/FIO₂) at 6 h, 12 h, and 18 h postoperatively. Pulmonary complications were defined as X-ray verified pneumonia/atelectasis, clinical signs of pneumonia, or supplementary oxygen beyond postoperative day 3. Patient-reported comfort during CPAP treatment was also evaluated. In total, 96 patients (ICPAP, n = 48; HCPAP, n = 48) were included, and the type of surgical procedure were evenly distributed between the groups. Oxygenation did not differ between the groups by 6 h, 12 h, or 18 h postoperatively (p = 0.1, 0.08, and 0.67, respectively). Nor was there any difference in X-ray verified pneumonia/atelectasis (p = 0.40) or supplementary oxygen beyond postoperative day 3 (p = 0.53). Clinical signs of pneumonia tended to be more frequent in the ICPAP group (p = 0.06), yet the difference was not statistically significant. Comfort scores were similar in both groups (p = 0.43), although a sensation of claustrophobia during treatment was only experienced in the HCPAP group (11% vs. 0%, p = 0.03). Compared with ICPAP, using HCPAP was associated with similar oxygenation (i.e., PaO₂/FIO₂ ratio) and a similar risk of pulmonary complications. However, HCPAP treatment was associated with a higher sensation of claustrophobia.

Clinical outcomes according to timing to invasive ventilation due to noninvasive ventilation failure in children

OBJECTIVE

Noninvasive ventilation (NIV) failure it has been associated to worst clinical outcomes due to a delay in intubation and initiation of invasive mechanical ventilation (IMV). There is a lack of evidence in pediatric patients regarding this topic. The objective was to deter-mine the association between duration of IMV and length of stay, with duration of NIV prior tointubation/IMV in pediatric patients.

DESIGN

A prospective cohort study since January 2015 to October 2019.

SETTING

A pediatric intensive care unit.

PATIENTS

Children under 15 years with acute respiratory failure who failed to noninvasive ventilation.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

Demographic variables, pediatric index of mortality (PIM2), pediatric acute respiratory distress syndrome (PARDS) diagnosis, IMV and NIV duration, PICU LOS were registered and intrahospital mortality.

RESULTS

A total of 109 patients with a median (IQR) age of 7 (3-14) months were included. The main diagnosis was pneumonia (89.9%). PARDS was diagnosed in 37.6% of the sample. No association was found between NIV duration and duration of IMV after Kaplan-Meier analysis (Log rank P = .479). There was no significant difference between PICU LOS (P = .253) or hospital LOS (P = 0.669), when categorized by NIV duration before intubation. PARDS diagnosis was associated to an increased length of invasive ventilation (HR: 0.64 [95% IC: 0.42-0.99]).

CONCLUSIONS

No association was found between NIV duration prior to intubation and duration of invasive ventilation in critical pediatric patients with acute respiratory failure.

Clinical practice guidelines: management of severe bronchiolitis in infants under 12 months old admitted to a pediatric critical care unit

PURPOSE

We present guidelines for the management of infants under 12 months of age with severe bronchiolitis with the aim of creating a series of pragmatic recommendations for a patient subgroup that is poorly individualized in national and international guidelines.

METHODS

Twenty-five French-speaking experts, all members of the Groupe Francophone de Réanimation et Urgence Pédiatriques (French-speaking group of paediatric intensive and emergency care; GFRUP) (Algeria, Belgium, Canada, France, Switzerland), collaborated from 2021 to 2022 through teleconferences and face-to-face meetings. The guidelines cover five areas: (1) criteria for admission to a pediatric critical care unit, (2) environment and monitoring, (3) feeding and hydration, (4) ventilatory support and (5) adjuvant therapies. The questions were written in the Patient-Intervention-Comparison-Outcome (PICO) format. An extensive Anglophone and Francophone literature search indexed in the MEDLINE database via PubMed, Web of Science, Cochrane and Embase was performed using pre-established keywords. The texts were analyzed and classified according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. When this method did not apply, an expert opinion was given. Each of these recommendations was voted on by all the experts according to the Delphi methodology.

RESULTS

This group proposes 40 recommendations. The GRADE methodology could be applied for 17 of them (3 strong, 14 conditional) and an expert opinion was given for the remaining 23. All received strong approval during the first round of voting.

CONCLUSION

These guidelines cover the different aspects in the management of severe bronchiolitis in infants admitted to pediatric critical care units. Compared to the different ways to manage patients with severe bronchiolitis described in the literature, our original work proposes an overall less invasive approach in terms of monitoring and treatment.