BACKGROUND: Mechanical insufflation-exsufflation (MI-E) uses positive and negative pressures to assist weak cough and help clear airway secretions. Laryngeal visualization during MI-E has revealed that inappropriate upper airway responses can impede its efficacy. However, the dynamics of pressure transmission in the upper airways during MI-E is unclear, as are the relationships between anatomical structure, pressure and airflow.
OBJECTIVE: Can airflow resistance through the upper airway and the larynx feasibly be calculated during MI-E, and if so, how are the pressures transmitted to the trachea?
METHODS: Cross-sectional study of ten healthy adults, where MI-E was provided with and without active cough, employing pressure settings +20/-40 and ±40 cmH2O. Airflow and pressure at the level of the facemask were measured using a pneumotachograph, while pressure transducers (positioned via transnasal fiberoptic laryngoscopy) recorded pressures above the larynx and within the trachea. Upper airway resistance (Ruaw) and translaryngeal resistance (Rtl) were calculated (cmH2O/L/sec) and compared to direct observations via laryngoscopy.
RESULTS: Positive pressures reached the trachea effectively, while negative tracheal pressures during exsufflation were approximately half of the intended settings. Insufflation pressure increased slightly when passing through the larynx. Participant effort influenced tracheal pressures and the resistances, with findings consistent with laryngoscopic observations. During MI-E, resistance appears dynamic, with Ruaw exceeding Rtl. Inappropriate laryngeal closure increased Rtl during both positive and negative pressures.
CONCLUSIONS: Upper airway and translaryngeal resistance can feasibly be calculated during MI-E. The findings indicate different transmission dynamics for positive and negative pressures, and that resistances are influenced by participant effort. The findings support using lower insufflation pressures and higher negative pressures in clinical practice.

BACKGROUND: A mechanical insufflation-exsufflation (MI-E) device is a commonly used tool for airway clearance in children with an ineffective cough. Whereas the device has been shown to have multiple benefits, limited evidence exists regarding parents\' experiences with its home use in the Canadian context. This study\'s objective was to explore the perspectives and experiences of parents who receive service through the IWK Health Centre and use an MI-E device at home with their child.
METHODS: The study used an interpretive description design. Semi-structured interviews, conducted with 9 participants, were audio recorded and transcribed verbatim. Transcripts were analyzed using a reflective thematic process.
RESULTS: Seven mothers and 2 fathers were interviewed. Following analysis, 3 themes were identified: (1) Learning about the MI-E device described participants\' journey from becoming aware of the device to acquiring knowledge and skills about its use; (2) using the device detailed the integral role the MI-E device played in their lives, including decisions around use, and parental role; and (3) changing lives outlined the physical, emotional, and social benefits the device provided to the child and their family.
CONCLUSIONS: Participants provided detailed descriptions of their journey from learning to integrating the MI-E device into their child\'s daily routine and family life. Its multiple associated benefits improved the child\'s and their family\'s quality of life. However, better education on its use was highlighted as a need for both parents and the health care professionals who work with them.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive diaphragm weakness and deteriorating lung function. Bulbar involvement and cough weakness contribute to respiratory morbidity and mortality. ALS-related respiratory failure significantly affects quality of life and is the leading cause of death. Non-invasive ventilation (NIV), which is the main recognized treatment for alleviating the symptoms of respiratory failure, prolongs survival and improves quality of life. However, the optimal timing for the initiation of NIV is still a matter of debate. NIV is a complex intervention. Multiple factors influence the efficacy of NIV and patient adherence. The aim of this work was to develop practical evidence-based advices to standardize the respiratory care of ALS patients in French tertiary care centres.
METHODS: For each proposal, a French expert panel systematically searched an indexed bibliography and prepared a written literature review that was then shared and discussed. A combined draft was prepared by the chairman for further discussion. All of the proposals were unanimously approved by the expert panel.
RESULTS: The French expert panel updated the criteria for initiating NIV in ALS patients. The most recent criteria were established in 2005. Practical advice for NIV initiation were included and the value of each tool available for NIV monitoring was reviewed. A strategy to optimize NIV parameters was suggested. Revisions were also suggested for the use of mechanically assisted cough devices in ALS patients.
CONCLUSIONS: Our French expert panel proposes an evidence-based review to update the respiratory care recommendations for ALS patients in daily practice.

BACKGROUND: Mechanical insufflation-exsufflation (MI-E) and manually assisted cough are frequently employed cough augmentation methods for enhancing cough efficiency in individuals with cervical spinal cord injury (CSCI). This study aimed to evaluate the synergistic impact of combining manually assisted cough and MI-E on cough peak flow in subjects with CSCI and identify their related factors.
METHODS: Fifteen subjects with CSCI with cough peak flow > -270 L/min underwent 5 consecutive days of 5 cough augmentation sessions; cough peak flow during exsufflation and the total insufflation volume (TIV) during insufflation were measured. Only MI-E was administered on days 1 and 5, whereas on days 2-4 one MI-E-only session followed by 3 MI-E and manually assisted cough sessions was implemented followed by a fifth MI-E-only session. The cumulative and carry-over effects of increasing treatment sessions and any associated factor on cough peak flow during MI-E-assisted coughing were assessed using a linear mixed model (LMM) with repetitive air-flow measurements within the same participants.
RESULTS: No cumulative or carry-over effects of manually assisted cough and MI-E were shown with the accumulation of treatment days or sessions. The LMM confirmed that using manually assisted cough (-0.283 L/s, P < .001), TIV (-0.045 L/s, P = .002), and the individual manually assisted cough variance (-0.022 L/s, P = .01) significantly influenced cough peak flow. Estimated mean cough peak flows for MI-E with manually assisted cough and MI-E alone were -4.006 L/s (95% CI -4.237 to -3.775) and -3.723 L/s (95% CI -3.953 to -3.492), respectively, surpassing the initial voluntary cough peak flow without MI-E assistance (-1.65 ± 0.53 L/s).
CONCLUSIONS: The use of manually assisted cough and amount of TIV correlated with improved cough peak flow, emphasizing the importance of adequate in-expiratory support. No carry-over effect was associated with using manually assisted cough, highlighting the need to combine MI-E with manually assisted cough for each MI-E treatment to achieve optimal cough effectiveness.

We report a case of post-extubation respiratory failure due to insufficient airway mucus expectoration that was successfully treated using mechanical insufflation-exsufflation (MI-E). A 32-year-old woman with a long-term history of steroid therapy for Blau syndrome was admitted to our intensive care unit with refractory hypoxemia due to pneumonia associated with the novel coronavirus disease 2019. Mechanical ventilation with veno-venous extracorporeal membrane oxygenation (VV-ECMO) was required due to severe hypoxemia. She was weaned from VV-ECMO on the 10th day and extubated on the 13th day. A few hours after extubation, she presented respiratory distress due to massive pulmonary atelectasis caused by sputum accumulation as a result of the impaired cough reflex. MI-E was applied to facilitate coughing and sputum expectoration. MI-E dramatically improved the atelectasis and prevented reintubation. This case suggests that MI-E, which is primarily used to treat chronic neuromuscular diseases, may also be effective in treating acute respiratory failure.

BACKGROUND: Respiratory muscle weakness can impair cough function, leading to lower respiratory tract infections. These infections are an important contributor to morbidity and mortality in patients with neuromuscular disease. Mechanical insufflation-exsufflation (MIE) is used to augment cough function in these patients. Although MIE is widely used, there are few data to advise on the optimal technique. Since the introduction of MIE, the recommended pressures to be delivered have increased. There are concerns regarding the use of higher pressures and their potential to cause lung derecruitment and upper airway closure.
OBJECTIVE: What is the impact of high-pressure MIE (HP-MIE) on lung recruitment, respiratory drive, upper airway flow, and patient comfort, compared with low-pressure MIE (LP-MIE), in patients with respiratory muscle weakness?
METHODS: Clinically stable patients using domiciliary MIE with respiratory muscle weakness secondary to Duchenne muscle dystrophy, spinal cord injury, or long-term tracheostomy ventilation received LP-MIE (30/-30 cm H2O) and HP-MIE (60/-60 cm H2O) in a random sequence. Lung recruitment, neural respiratory drive, and cough peak expiratory flow were measured throughout, and patients reported comfort and breathlessness following each intervention.
RESULTS: A total of 29 patients (10 with Duchenne muscle dystrophy, eight with spinal cord injury, and 11 with long-term tracheostomy ventilation) were included in this study. HP-MIE augmented cough peak expiratory flow compared with LP-MIE (mean cough peak expiratory flow HP-MIE 228 ± 81 L/min vs LP-MIE 179 ± 67 L/min; P = .0001) without any significant change in lung recruitment, neural respiratory drive, or patient-reported breathlessness. However, in patients with more pronounced respiratory muscle weakness, HP-MIE resulted in an increased rate of upper airway closure and patient discomfort that may have an impact on clinical efficacy.
CONCLUSIONS: HP-MIE did not lead to lung derecruitment or breathlessness compared with LP-MIE. However, it was poorly tolerated in individuals with advanced respiratory muscle weakness. HP-MIE generates more upper airway closure than LP-MIE, which may be missed if cough peak expiratory flow is used as the sole titration target.
BACKGROUND: ClinicalTrials.gov; No.: NCT02753959; URL: www.
RESULTS: gov.

Amyotrophic lateral sclerosis (ALS) is a rare, neurodegenerative motor neuron disease that affects voluntary muscle movement. Often, difficulty in coughing, breathing, and swallowing are sequela associated with the condition, and the presence of bulbar muscle predominant weakness results in deleterious effects on airway clearance and secretion management. This narrative review will provide practical guidance for clinicians treating this population. Cough insufficiency in this population typically manifests as a prolonged, slow, weak cough effort that impedes the clearability of secretions and airway protection. Dystussia and dysphagia frequently occur simultaneously in bulbar dysfunction, subsequently impacting respiratory health. Measures of respiratory strength should be obtained and monitored every 3-6 months, preferably in a multidisciplinary clinic setting. Cough augmentation, whether manual or mechanical techniques, should be sought as early in the disease progression as possible to adequately control secretions in the proximal airways. This airway clearance strategy can aid in the prevention and treatment of respiratory tract infections (RTIs), which can pose a significant clinical hurdle to those with ALS. The use of mechanical insufflation-exsufflation may be complicated by severe bulbar dysfunction rendering this technique ineffective. Though peripheral airway clearance strategies, such as high-frequency chest-wall compression, have the advantage of being less impacted by bulbar dysfunction, it is only recommended this modality be used in conjunction with, versus in lieu of, proximal strategies. Salivary secretion management includes the use of anticholinergics, botulinum toxin, and radiation therapy depending on severity and desire for relief.

Mechanical insufflation-exsufflation (MIE) facilitates airway clearance to mitigate respiratory infection, decompensation, and ultimately the need for intubation and placement of a tracheostomy tube. Despite widespread adoption as a respiratory support intervention for motor neuron disease, muscular dystrophy, spinal cord injury, and other diseases associated with ventilatory pump failure and ineffective cough peak flow, there is debate in the clinical community about how to optimize settings when MIE is implemented. This article will demonstrate the clinical utility of MIE graphics in titrating the initial MIE settings, guiding upper airway and lung protective strategies and providing insight to clinicians for ongoing clinical management.

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.

Daily application of mechanical insufflation-exsufflation (MI-E) is used increasingly in patients with neuromuscular diseases (NMDs) to prevent pulmonary congestion and thereby respiratory tract infections, although its beneficial effect remains uncertain. We, therefore, conducted a systematic review, registered in PROSPERO (CRD42020158278), to compile available evidence for daily MI-E use in subjects with NMDs and stable respiratory condition.
We performed a systematic comprehensive search of MEDLINE, Embase, CINAHL, and Web of Science up to December 23, 2021. We excluded articles studying the effect of MI-E in case of acute respiratory failure or infections and studies comparing different MI-E devices and settings. Studied outcomes were prevalence and severity of respiratory infections, lung function, respiratory characteristics, and patient satisfaction. We performed a meta-analysis using DerSimonian-Laird random effects model and assessed methodological quality by using the Alberta Heritage Foundation for Medical Research tool.
A total of 3,374 records were screened, of which 25 were included, studying 608 subjects. One randomized controlled trial (RCT) found a trend toward reduced duration of respiratory infections compared to air stacking (AS) that was not statistically significant. Long-term effects on pulmonary function tests (PFT) results were reported in one RCT and one retrospective study, with mixed results regarding vital capacity. Most studies compared PFT results before and immediately after MI-E use. Meta-analysis showed an overall beneficial effect of MI-E on cough peak flow (CPF) compared to unassisted CPF (mean difference 91.6 L/min [95% CI 28.3-155.0], P < .001). Subject satisfaction was high, though possibly influenced by major bias.
There is limited evidence available to support beneficial effects of daily use of MI-E in clinically stable subjects with NMDs, with the possible exception of increased CPF immediately after MI-E application. Lack of longitudinal studies preclude conclusions regarding long-term effects. The very limited data comparing MI-E to AS preclude comparisons.