Importance of Individualized Pressure Settings in Mechanical Insufflation-Exsufflation for Lung Volume Recruitment: A...

Lung volume recruitment (LVR) has been proposed as a treatment to maintain respiratory health in patients with neuromuscular diseases who frequently develop restrictive ventilatory impairment due to muscle weakness. LVR applies noninvasive mechanical pressure techniques to maintain and improve pulmonary and chest wall compliance and to preserve vital capacity. Various methods of LVR have been developed, which can be classified into two types: the stacked-breath method and the single-breath method. Mechanical insufflation-exsufflation (MI-E) is one approach categorized under the single-breath method. Although the clinical use of pressure settings in MI-E varies, inspiratory pressure levels around 40 cmH₂O are sometimes applied in practice. However, such settings may result in patient discomfort and raise safety concerns. Given the limited clinical guidance available, it may be more appropriate to determine individualized settings based on each patient's impairment level, pulmonary mechanics, and tolerance. This case report describes such an approach to LVR using the single-breath method with MI-E in a patient with amyotrophic lateral sclerosis (ALS). To determine the optimal inspiratory pressure, three parameters were assessed at each pressure level: expiratory volume, subjective perception of lung expansion, and immediate subjective effects following inspiration. As the patient reported discomfort at 30 cmH₂O, the final inspiratory pressure was set at 25 cmH₂O. This level of inspiratory assistance led to improvements in vocal loudness and alleviated breathlessness during speech. These positive effects contributed to the patient's acceptance of the intervention and its continued use after discharge to home care. This case highlights the importance of tailoring LVR settings to optimize effectiveness, patient comfort, and safety, based on pulmonary mechanics, bedside volume assessment, and patient-reported respiratory status.