Bronchial Clearance Carried Out With a Mechanical In-exsufflator vs. a Manual Respiratory Physiotherapy Technique in Hospitalized Elderly People

Everywhere in the world, life expectancy is increasing. Currently, most individuals can expect to live up to 60 years and beyond. In all countries, the number and proportion of older adult in the population are rising. By 2030, one in six people in the world will be 60 years old or older.

France is also seeing its population age, with the number of older people increasing from 14% in 2014 to 21% in 2022. In 2018, elderly people accounted for 30% of short-stay hospitalizations. One of the most common causes of hospitalization for older adult is respiratory system pathologies, second only to cardiovascular system pathologies. Admission for a respiratory pathology is often associated with bronchial congestion. Infectious or viral pneumonia is often the terminal illness for the older adult. In the United States, 1 million old patients are hospitalized for this pathology, and 30% of them will die within the year.

Old people are more susceptible to pneumonia due to several factors, including impaired gag reflex, reduced muco-ciliary function, weakened immunity, impaired fever response, and various degrees of cardiopulmonary dysfunction. Additionally, central nervous system disorders and/or impaired gag reflex increase the risk of aspiration pneumonia in old patients. The majority of these patients develop a productive cough, but unfortunately, their ability to cough effectively is often reduced.

Aging leads to various changes in the respiratory system. The thoracic cage and spine deform due to calcification and osteoporosis, resulting in stiffness. The thoracic wall stiffens, making mobilization more difficult and increasing the muscular work required for expansion during inspiration. The diaphragm is in a less favorable position to contract effectively. Expiration becomes less efficient, leading to an increase in residual volume (RV) and promoting what is called "senile emphysema," where air spaces dilate and dead spaces increase. This leads to an increase in functional residual capacity and RV, reducing vital capacity. Additionally, respiratory muscles lose strength due to muscle atrophy and decreased fast-twitch fibers. These mechanisms can compromise ventilation, mucus clearance, and cough effectiveness, all essential for preventing bronchial congestion.

The effectiveness of Mechanical Insufflation-Exsufflation (MI-E) in airway clearance has been demonstrated in children and adults with neuromuscular pathologies.

Since the respiratory function of old people may be similar to that of patients with neuromuscular pathologies due to age-related loss of respiratory capacity and cough strength, it would be interesting to specifically study the use of MI-E in this population. Our previous study (ClinicalTrials.gov Identifier: NCT05090696) showed that old people tolerated MI-E well (low discomfort and no changes in vital signs). After the first session of bronchial clearance with MI-E, dyspnea decreased significantly (median Borg scale before session = 2.8 versus after = 1.8, p = 0.004). Additionally, cough strength increased across all sessions (mean pre = 130 vs. post = 145, p = 0.005).

Following this initial study, the investigators wondered if the use of MI-E would be more effective than a session of manual physiotherapy.