Autogenic Drainage Versus Mechanical Percussion in Children With Cystic Fibrosis

Cystic fibrosis (CF) is a life-limiting autosomal recessive genetic disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Dysfunction of the CFTR protein leads to impaired chloride and water transport across epithelial surfaces, resulting in the production of thick, dehydrated secretions in multiple organ systems, particularly the respiratory tract. The accumulation of viscous mucus within the airways contributes to chronic airway obstruction, recurrent pulmonary infections, persistent inflammation, progressive lung damage, and declining respiratory function. Despite advances in pharmacological treatment and supportive care, pulmonary complications remain the leading cause of morbidity and mortality in individuals with cystic fibrosis.

Airway clearance therapy is a fundamental component of respiratory management in patients with CF. The primary objective of airway clearance techniques (ACTs) is to mobilize and remove retained airway secretions, thereby improving ventilation, reducing airway obstruction, minimizing infection risk, preserving lung function, and enhancing quality of life. Various ACTs are available and are routinely incorporated into multidisciplinary CF care programs. However, determining the most effective airway clearance strategy remains challenging because patient responses vary and comparative evidence among techniques is often limited.

Autogenic drainage (AD) is an airway clearance technique based on controlled breathing at different lung volumes. The technique consists of three phases: unsticking, collecting, and evacuating secretions. Through carefully regulated inspiratory and expiratory airflow, AD promotes mucus mobilization from peripheral airways toward central airways where it can be effectively expectorated. Because the technique relies on self-regulated breathing rather than external mechanical forces, it may improve patient comfort, encourage independence, and facilitate long-term adherence. Previous studies have suggested that AD may improve pulmonary function, reduce airway resistance, enhance mucus clearance, and improve patient satisfaction. Nevertheless, evidence in pediatric populations remains limited.

Mechanical percussion is another commonly utilized airway clearance intervention in cystic fibrosis management. This technique employs rhythmic mechanical vibrations or percussion applied externally to the thoracic cage to loosen mucus adhered to airway walls. Mechanical percussion aims to facilitate mucus mobilization and subsequent clearance from the respiratory tract. The technique is frequently used in pediatric respiratory rehabilitation because it requires minimal active participation from younger children and can be administered by healthcare professionals or caregivers. Several studies have reported beneficial effects of mechanical percussion on secretion clearance and respiratory status. However, concerns regarding comfort, treatment burden, and long-term adherence have led clinicians to explore alternative airway clearance approaches.

Although both autogenic drainage and mechanical percussion are widely used in clinical practice, direct comparisons between these interventions in children with cystic fibrosis are scarce. Existing studies often include mixed age groups, employ heterogeneous outcome measures, or focus primarily on short-term physiological responses. Furthermore, limited evidence is available regarding their comparative effects on patient-centered outcomes such as dyspnea and health-related quality of life. Consequently, there remains uncertainty regarding which intervention provides superior clinical benefits for pediatric patients with CF.

The present study is designed to address this gap in the literature by directly comparing autogenic drainage and mechanical percussion in children diagnosed with cystic fibrosis. The study will employ a randomized clinical trial design to evaluate the relative effectiveness of these interventions on respiratory function, symptom burden, and quality of life. Participants meeting eligibility criteria will be recruited from tertiary care healthcare facilities and randomly allocated to one of two intervention groups.

Participants assigned to the Autogenic Drainage Group will receive therapist-guided autogenic drainage sessions. The intervention will be delivered according to standardized clinical procedures and will emphasize controlled breathing patterns designed to mobilize secretions from distal to proximal airways. Participants will receive training and supervision from qualified physiotherapists to ensure proper technique execution and treatment consistency.

Participants assigned to the Mechanical Percussion Group will receive standardized mechanical chest percussion therapy using a mechanical percussion device. Treatment protocols will follow established clinical recommendations to ensure consistent delivery and participant safety. Sessions will be administered by trained physiotherapists using appropriate positioning and device settings tailored to individual patient tolerance.

Both intervention groups will receive treatment five days per week for six consecutive weeks. Each treatment session will last approximately ten minutes and will be delivered under professional supervision to maximize adherence and ensure protocol fidelity. The frequency and duration of treatment were selected based on previous research demonstrating clinically meaningful improvements in respiratory outcomes among pediatric respiratory populations.

The primary outcomes of interest will include pulmonary function parameters measured using spirometry. Forced Expiratory Volume in One Second (FEV₁) and Forced Vital Capacity (FVC) will be assessed as objective indicators of respiratory function and airway clearance effectiveness. Spirometry remains the gold-standard method for evaluating pulmonary status in individuals with cystic fibrosis and provides clinically relevant information regarding disease progression and treatment response.

Secondary outcomes will include dyspnea and health-related quality of life. Dyspnea will be evaluated using the Modified Borg Dyspnea Scale, a validated subjective measure commonly used to assess perceived breathlessness in respiratory populations. Health-related quality of life will be assessed using the Cystic Fibrosis Questionnaire-Revised (CFQ-R), a disease-specific instrument that evaluates the impact of cystic fibrosis on physical, emotional, and social functioning.

Outcome assessments will be conducted at baseline before intervention initiation and repeated following completion of the six-week treatment program. Statistical analyses will compare changes within each intervention group and between groups to determine whether one airway clearance technique demonstrates superior effectiveness.

The findings of this study are expected to contribute important evidence regarding airway clearance management in pediatric cystic fibrosis. By directly comparing autogenic drainage and mechanical percussion using objective and patient-reported outcome measures, the study may help clinicians make informed treatment decisions and optimize respiratory rehabilitation strategies. Improved understanding of the relative benefits of these interventions may ultimately enhance pulmonary health, reduce symptom burden, promote treatment adherence, and improve quality of life for children living with cystic fibrosis.

• Cystic Fibrosis Questionnaire-Revised (CFQ-R) Total Score [Time frame: Baseline (Week 0) and post-intervention (Week 6).]