Long-Term Mechanical Insufflation-Exsufflation Cough Assistance in Neuromuscular Disease: Patterns of Use and Lessons for Application

Abstract

BACKGROUND: Mechanical insufflation-exsufflation (MI-E) devices increase expiratory air flow and thereby promote increased cough peak flow (CPF) in conjunction with a cough. There is little research looking at long-term use of MI-E in subjects with neuromuscular disease (NMD), and no long-term study has reported CPF, MI-E device settings, and adherence. METHODS: We evaluated 181 patient records (130 adults, 51 children) of individuals who received a MI-E device from our center between February 2014 and February 2018. Median age (interquartile range [IQR]) was 27 (14-51) y. Duchenne muscular dystrophy (DMD), spinal muscular atrophy (SMA), and amyotrophic lateral sclerosis (ALS) were the 3 most common diagnoses. RESULTS: MI-E devices were provided to the weakest subjects with a CPF < 160 L/min. Median (IQR) settings were insufflation, 25 (23-30) cm H 2 O, exsufflation ؊35 (؊30 to ؊40) cm H 2 O, insufflation time 1.5 (1.3-1.7) s, exsufflation time 1.8 (1.5-2.0) s, and pause 1.5 (1.3-2.0) s. The inspiratory flow profile was set to high in all subjects, and no subject used supplemental oxygen with the MI-E device. When comparing insufflation pressures to exsufflation pressures, a greater negative pressure was used relative to positive pressure (P < .001). When comparing insufflation to exsufflation time, there was a significantly longer exsufflation duration (P < .001). Median (IQR) CPF at the start of MI-E was 60 (10-100) L/min. There was no correlation between either insufflation or exsufflation pressures and CPF. Median (IQR) usage for the group was 60% (13.5-100%) of days for the total days. Subjects with tracheostomies or SMA type I had the greatest adherence to treatment. Median (IQR) duration of MI-E use was 17 (8.5-32) months. Ninety-six percent of subjects were receiving ventilatory support. CONCLUSIONS: Greater exsufflation pressures than insufflation pressures, together with a shorter insufflation time than exsufflation time, were used. Predicting good adherence among the subjects was difficult. Subjects who produced daily secretions were more likely to use MI-E every day.

Prevalence of long‐term mechanical insufflation‐exsufflation in children with neurological conditions: a population‐based study

“…7,9 MI-E may be implemented to prevent and treat respiratory events, but also to familiarize the child with the device, as well as maintaining chest wall compliance. 11 In CP, initiation of MI-E cannot rely only on the diagnosis, and preventive use of MI-E in this group of children appears untargeted. However, other techniques (e.g., air-stacking using glossopharyngeal breathing) are limited in young or non-cooperative children.…”

“…MI‐E is well established in neuromuscular disorders (NMDs), especially for those with severe muscular weakness, 5–7 preventing airway infections and hospitalizations 3,8 . Daily use supports airway clearance and promotes deep inspirations, especially in young children who do not benefit from other airway clearance techniques 5–7,9–11 . Recently, MI‐E treatment has been suggested for children with impaired cough due to quadriplegic cerebral palsy (CP), 12,13 as severe motor impairment may lead to compromised airway clearance and hospitalizations 1,2,14–17 …”

Long-Term Mechanical Ventilation: Recommendations of the Swiss Society of Pulmonology

“…MIE settings. A recent report from an expert center (Royal Brompton Hospital, UK) provided average settings for MIE from 181 patients with NMD (130 adults, 51 children; 156 with NIV, 8 with a tracheostomy) as well as an algorithm for establishing MIE settings [190]. Values reported for adults were (median; IQR): 28 cm H 2 O (25–30) for insufflation; –35 cm H 2 O (–32; –40) for exsufflation; TI: 1.5 s (1.3–1.8); expiratory time: 2.0 s (1.5–2.4); pause: 1.5 s (1.3–2.0).…”

ERS International Congress, Madrid, 2019: highlights from the Sleep and Clinical Physiology Assembly

“…The role of cough assist devices can be very important for airway secretion clearance in NMD, when the peak of cough flow values are <160 L·min −1 [ 64 – 66 ]. Setting cough assist devices involves adjustment of the positive and negative pressures, the inspiratory, expiratory and pause times, as well as the inspiratory flow rate [ 66 – 68 ]. Cough assist devices are more effective with greater exsufflation and longer insufflation times, whilst the optimisation of its settings in bulbar amyotrophic lateral sclerosis is critical [ 69 – 71 ].…”