Clinical UM Guideline

This document addresses the use of mechanical insufflation-exsufflation (MI-E) devices (also known as “cough assist devices”) to assist coughing (for example, the Synclara™ Cough Assist Device System) to promote the clearance of respiratory secretions in individuals with impaired ability to cough or otherwise expel them on their own.

Note: Other types of mucus clearance systems are not addressed within this document (for example, the Flutter^® Mucus Clearance System, the Acapella^® Vibratory PEP Therapy System, the Volara^™ intrapulmonary percussive ventilation system, etc.).

Note: For information regarding other types of airway clearance systems, please refer to:

• CG-DME-43 High Frequency Chest Compression Devices for Airway Clearance
• CG-DME-47 Noninvasive Home Ventilator Therapy for Respiratory Failure
• DME.00012 Intrapulmonary Percussive Ventilation Devices

Medically Necessary:

Use of a mechanical insufflation-exsufflation device (see Discussion/General Information section below for examples) is considered medically necessary when all of the following are met:

1. The individual is unable to cough or clear respiratory secretions due to a chronic neuromuscular disorder or respiratory muscle weakness (for example, but not limited to, muscular dystrophy, spinal muscular atrophy, multiple sclerosis, amyotrophic lateral sclerosis, poliomyelitis and spinal cord injuries); and
2. Other methods to improve cough effectiveness and secretion clearance (for example, chest physiotherapy [CPT], bagging, “frog” breathing, or breath stacking) have resulted in inadequate clearance of respiratory secretions or there is documentation that such methods are unlikely to generate adequate secretion clearance.

Not Medically Necessary:

Mechanical insufflation-exsufflation devices are considered not medically necessary when the above criteria have not been met and for all other indications including, but not limited to, chronic obstructive pulmonary disease.

The following codes for treatments and procedures applicable to this guideline are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services may be Medically Necessary when criteria are met:

When services are Not Medically Necessary:
For the procedure code listed above when criteria are not met or for situations designated in the Clinical Indications section as not medically necessary, including for the following diagnosis:

Individuals with neuromuscular disease (NMD) or spinal cord injury may have a weak cough that limits the ability to expel mucus from the lungs, thereby increasing the risk of choking and recurrent respiratory tract infections. Cough augmentation techniques aim to improve the clearance of excessive or retained lung secretions. CPT, which is also known as percussion and postural drainage, is traditionally seen as the standard of care of secretion clearance methods. Other methods to improve cough effectiveness and secretion clearance include bagging (using a self-inflating bag commonly used for resuscitation), “frog” breathing (a method of gulping to help a person take in a bigger volume of air), and breath stacking (taking in a number of sequential breaths without breathing out between breaths) (Morrow, 2021). However, these methods are not tolerated or effective in all individuals. In some cases, there may be no available or capable caregiver or partner resource to perform CPT, or manual CPT may be contraindicated for the individual’s condition. An alternative is use of an MI-E device which induces coughing and clears secretions by applying positive pressure to the airway, then rapidly shifting to negative pressure. A number of these devices have been cleared by the U.S. Food and Drug Administration (FDA), including the Synclara^™ Cough System (Hill-Rom Holdings, Inc., Chicago, IL), BiWaze^® Cough System (ABM Respiratory Care LLC, Eagan, MN), Pegaso Cough (Dima Italia Srl, Bologna, Italy) and CoughAssist T70 (Philips, Inc., Cambridge, MA), for mobilization of endobronchial secretions. MI-E devices are sometimes referred to as “cough assist devices”.

In 2017, Auger and colleagues conducted a systematic review of the benefits and risks of the use of MI-E devices for airway clearance in individuals with NMD. A total of 12 studies were included involving 325 participants. All studies evaluated change of pulmonary function parameters, such as peak expiratory flow, but none reported long-term outcomes. The quality of the selected studies was judged to be poor. The lack of robust data supporting the use of MI-E devices was highlighted. However, it was noted that most European and American guidelines recommend the use of MI-E despite low-level evidence.

In a 2021 Cochrane review, Morrow and colleagues evaluated cough augmentation techniques for people with chronic neuromuscular disorders. The review included 11 randomized controlled trials (RCTs), quasi-RCTs, and randomized cross-over trials involving 287 participants. A number of different cough augmentation techniques were compared including MI-E. None of the included studies reported on the primary outcomes of number and duration of unscheduled hospital admissions. It was found that a range of cough augmentation techniques may increase peak cough flow compared to unassisted cough (199 participants, 8 RCTs), but the evidence is very uncertain. There was not enough evidence to show whether any one technique was better than another in improving cough quality. It was concluded that there is currently very low certainty evidence for or against the safety and effectiveness of cough augmentation techniques in people with chronic NMD, and more research is needed.

Veldhoen and colleagues (2023) reported the results of a systematic review and meta-analysis of the effects of daily use of MI-E in individuals with NMD. Outcomes that were studied included prevalence and severity of respiratory infections, lung function, respiratory characteristics, and patient satisfaction. A total of 25 studies were included, involving 608 participants. Only 3 studies were RCTs (Kim, 2016; Lacombe, 2014; Rafiq, 2015). The 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% confidence interval {CI}, 28.3–155.0], p<0.001). Most studies reported high participant satisfaction with MI-E although this result was at least partly influenced by selection and study bias. The authors concluded that there are limited data available to analyze the effect of MI-E on respiratory tract infections or hospital admissions. MI-E was found to have an immediate beneficial effect on CPF, but evidence on longer-term lung function improvement is lacking.

A study by Sivasothy and colleagues (2001) examined the effect of MI-E on cough flow of individuals with chronic obstructive pulmonary disease (COPD). In individuals with COPD, MI-E somewhat unexpectedly decreased peak expiratory flow rate by 135 L/min (95% CI, 30 to 312). The authors concluded that individuals with COPD did not benefit from assisted cough techniques and that mechanical insufflation may exacerbate hyperinflation of the lung in individuals with COPD, contributing to the observed reduced cough expiratory volume.

A consensus statement from the American Thoracic Society (ATS) (Finder, 2004) noted that the use of MI-E is particularly important in preventing hospitalization or need for tracheostomy in individuals with Duchenne Muscular Dystrophy (DMD). In individuals with DMD with tracheostomies, MI-E offers a number of advantages over traditional suctioning, including clearance of secretions from peripheral airways, avoidance of mucosal trauma from direct tracheal suction, and improved patient comfort.

A clinical practice guideline from the American Association for Respiratory Care (AARC) (Strickland, 2013) reported that CPT is often not well tolerated or feasible in individuals with NMD. Accordingly, MI-E was cautiously recommended for children with weak cough, recommended for individuals with amyotrophic lateral sclerosis, and strongly recommended in individuals with DMD.

In 2023, the American College of Chest Physicians published a clinical guideline (Khan, 2023) on the respiratory management of patients with neuromuscular weakness. MI-E was recommended for individuals with NMD and reduced cough effectiveness, which cannot be adequately improved with alternative techniques. However, the recommendation was conditional and based on a very low certainty of evidence. It was noted that use of the device reduces morbidity and hospitalization although individuals can develop intolerance to the procedure.

In summary, despite limited evidence to support long-term improvement of lung function, MI-E devices are considered in accordance with generally accepted medical practice as an alternative to reduce morbidity and hospitalization for appropriately selected individuals with neuromuscular weakness who cannot tolerate alternative airway clearance methods.

Bagging: A cough stimulation technique using a self-inflating bag commonly used for resuscitation to increase the inspiratory volume and ultimately result in higher expiratory airflow at the expulsive phase of cough.

Breath stacking: A technique to improve cough efficiency in which a person takes in a number of sequential breaths without exhaling which allows the lungs take in more air than normal, followed by a short hold before slow expiration and cough.

Chest physiotherapy (CPT) (also known as chest physical therapy): The use of postural drainage, percussion, and vibration (PDPV) for airway clearance, which may also be referred to as percussion and postural drainage (P/PD). CPT is considered the standard of care of secretion clearance methods. This technique is time consuming, requires a skilled care provider and may be associated with discomfort, gastroesophageal reflux, and hypoxemia. The purpose of CPT is to improve mucociliary clearance and pulmonary function in order to reduce the risk of infection and lung damage.

Cough assist device: A machine that uses a facemask, mouthpiece, or tracheostomy to deliver mechanical insufflation-exsufflation to simulate a natural cough.

Frog breathing: A positive pressure breathing technique, also called glossopharyngeal breathing, which uses muscles of the mouth and pharynx to propel gulps of air into the lungs to increase air volume and thereby cough flows.

Mechanical insufflation-exsufflation: The application of positive air pressure to produce a large volume of air within the lungs (insufflation) followed by a rapid change to negative pressure (exsufflation) that helps mechanically stimulate coughs to expel mucus.

Peer Reviewed Publications:

1. Auger C, Hernando V, Galmiche H. Use of mechanical insufflation-exsufflation devices for airway clearance in subjects with neuromuscular disease. Respir Care. 2017; 62(2):236-245.
2. Kim SM, Choi WA, Won YH, Kang SW. A comparison of cough assistance techniques in patients with respiratory muscle weakness. Yonsei Med J. 2016; 57(6):1488-1493.
3. Lacombe M, Del Amo Castrillo L, Boré A, et al. Comparison of three cough-augmentation techniques in neuromuscular patients: mechanical insufflation combined with manually assisted cough, insufflation-exsufflation alone, and insufflation-exsufflation combined with manually assisted cough. Respiration. 2014; 88(3):215-222.
4. Rafiq MK, Bradburn M, Proctor AR, et al. A preliminary randomized trial of the mechanical insufflator-exsufflator versus breath-stacking technique in patients with amyotrophic lateral sclerosis. Amyotroph Lateral Scler Frontotemporal Degener. 2015; 16(7-8):448-455.
5. Sivasothy P, Brown L, Smith IE, Shneerson JM. Effect of manually assisted cough and mechanical insufflation on cough flow of normal subjects, patients with chronic obstructive pulmonary disease (COPD), and patients with respiratory muscle weakness. Thorax. 2001; 56(6):438-444.
6. Veldhoen ES, van der Wal R, Verweij-van den Oudenrijn LP, et al. Evidence for beneficial effect of daily use of mechanical insufflation-exsufflation in patients with neuromuscular diseases. Respir Care. 2023; 68(4):531-546.

Government Agency, Medical Society, and Other Authoritative Publications:

1. Finder JD, Birnkrant D, Carl J, et al. Respiratory care of the patient with Duchenne muscular dystrophy: ATS Consensus Statement. Am J Respir Crit Care Med. 2004; 170:456-465.
2. Khan A, Frazer-Green L, Amin R, et al. Respiratory management of patients with neuromuscular weakness: an American College of Chest Physicians Clinical Practice Guideline and Expert Panel Report. Chest. 2023; 164(2):394-413.
3. Morrow B, Argent A, Zampoli M, et al. Cough augmentation techniques for people with chronic neuromuscular disorders. Cochrane Database Syst Rev. 2021; 4(4):CD013170.
4. Strickland SL, Rubin BK, Drescher GS, et al. AARC Clinical Practice Guideline: effectiveness of nonpharmacologic airway clearance therapies in hospitalized patients. Respir Care. 2013; 58(12):2187-2193.

1. Muscular Dystrophy Association. Available at: www.mda.org. Accessed on March 14, 2024.

BiWaze^® Cough System
CoughAssist T70
Pegaso Cough
Synclara^™ Cough System

The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.