Sleep Medicine Network

Home-based Mechanical Ventilation and Neuromuscular Disease Section

Navigating the latest device supply chain challenge: Mechanical airway clearance

Airway clearance is integral for patients with respiratory muscle weakness and is divided into cough augmentation (proximal airways) and sputum mobilizing techniques (distal airways). Cough augmentation techniques provide lung volume recruitment on the insufflation phase, in addition to mobilization of secretions with augmentation of the peak expiratory flow rate to >160 L/min on the exhalation phase.

A mechanical insufflation-exsufflation (MI-E) device (T70 Cough Assist - Phillips) is now on indefinite backorder. This creates a dangerous situation for our patients requiring cough augmentation for survival. Alternative options that provide both MI-E and high frequency oscillation include two systems (Synclara Cough System – Hill-rom and the Biwaze Cough System-ABM Respiratory Care).

The Synclara can only be obtained in a direct-to-patient model, contracting with individual respiratory therapists, outside of the standard durable medical equipment model. The final MI-E model option is the VOCSYN multifunctional ventilator (ventilator, cough assist, nebulizer, oxygen concentrator, suction). This multifunction ventilator has had variable acceptance with HCPCS code E0467. If the VOCSYN is chosen, the patient cannot have been issued any component devices or have reached the 36-month cap for oxygen equipment (CR 10854 special payment rule, 42 CFR414.222).

As the supply of devices is exhausted, we will need to shift to evidence-based manual options. Manual cough augmentation can be done effectively with a bag-valve mask, using breath stacking to achieve maximal lung insufflation, optimizing the length tension relationship of elastic recoil on exhalation to increase peak cough flow (PCF).

This can be done alone but is more effective when combined with manually assisted cough (Bach JR. Chest. 1993;104[5]:1553-62). These interventions require training of the caregivers, using resources such as those found at www.canventottawa.ca.

With continued supply chain instability, manual airway clearance techniques should be considered in patients with less advanced cough impairment (PCF 160-270 L/min), to save the remaining devices for those with PCF of <160 L/min.

Jeanette Brown, MD, PhD
Karin Provost, DO, PhD

Members-at-Large