What are effective airway clearance techniques for Chronic Obstructive Pulmonary Disease (COPD) patients?

Airway Clearance Techniques for COPD Patients

For COPD patients, huffing (forced expiratory technique) should be taught as the primary active breathing technique, combined with positive expiratory pressure (PEP) devices when secretions are copious, while avoiding manually assisted cough which can be detrimental. 1

Primary Technique: Huffing (Forced Expiratory Technique)

Huffing is specifically recommended for COPD patients as it minimizes airway collapse that occurs with vigorous coughing. 1, 2

• Huffing consists of one or two forced expirations without glottic closure, starting from mid-lung to low lung volume, followed by relaxed breathing 1
• This technique generates lower intrapulmonary pressures than coughing, leading to less airway compression in patients with abnormally compliant central airways 1
• Huffing was as effective as directed cough in moving secretions proximally from all lung regions in COPD patients 1
• Grade C recommendation (low evidence, small benefit) 1

Adjunctive Device: Positive Expiratory Pressure (PEP)

When COPD patients have copious secretions, PEP devices (5-20 cm H₂O) should be added to huffing techniques. 1

• PEP improves mucus clearance by increasing gas pressure behind secretions through collateral ventilation and preventing airway collapse during expiration 1
• In the only outcome study of COPD patients with chronic bronchitis, PEP combined with forced expirations resulted in less cough, less mucus production, fewer exacerbations, and reduced antibiotic use after 5-12 months 1
• PEP devices are inexpensive, safe, and can be self-administered 1
• Temporary PEP (T-PEP) at low pressure (1 cm H₂O) reduced exacerbations at 1 and 3 months in severe COPD patients 3, 4

Active Breathing Techniques

Active cycle of breathing techniques and autogenic drainage can be effective alternatives for COPD patients who can master these techniques. 5

• Active breathing techniques have better evidence than passive techniques like postural drainage and percussion in COPD 5
• Autogenic drainage uses controlled expiratory airflow during tidal breathing at varying lung volumes to mobilize secretions centrally 1
• These techniques can be performed independently without caregiver assistance 1

Critical Contraindications

Manually assisted cough is contraindicated in COPD and should NOT be used. 1, 2, 6

• Manually assisted cough decreases peak expiratory flow by 144 L/min in COPD patients 2, 6
• This technique may be detrimental due to airflow obstruction 1, 6
• Grade D recommendation (negative benefit) 1

Postural Drainage: Limited Role

Traditional postural drainage with head-down tilt has low evidence in COPD and should not be a primary technique. 2, 5

• The evidence for passive techniques like postural drainage and percussion is low in COPD 5
• Flutter devices showed no difference in sputum volume or FEV₁ compared to postural drainage in COPD patients 1
• Modified postural drainage without head-down tilt can be used if gastroesophageal reflux or breathlessness is problematic 2

Oscillatory Devices: Conflicting Evidence

Oscillatory devices (Flutter, high-frequency chest wall oscillation) have conflicting evidence in COPD and should be considered only as alternatives when standard techniques fail. 1

• Flutter devices in COPD/chronic bronchitis patients showed no difference in sputum volume or FEV₁ compared to postural drainage 1
• Grade I recommendation (conflicting benefit) 1
• Intrapulmonary percussive ventilation reduced the need for non-invasive ventilation in hypercapnic respiratory failure during acute exacerbations 7

During Acute Exacerbations

During acute COPD exacerbations, mechanical vibration and non-oscillating PEP mask therapy increase sputum expectoration in patients with copious secretions. 7

• Airway clearance techniques are safe during exacerbations, except continuous chest wall percussion which reduced FEV₁ 7
• PEP mask therapy reduced the duration of non-invasive ventilation in hypercapnic respiratory failure 7
• Techniques applying positive airway pressure may reduce hospital length of stay 7

Common Pitfalls to Avoid

• Do not use vigorous coughing - this causes airway collapse in COPD; use huffing instead 1, 2
• Do not apply manually assisted cough - this worsens peak expiratory flow 1, 2, 6
• Do not rely solely on percussion and vibration - these have low evidence as standalone techniques 5
• Do not use continuous chest wall percussion - this can reduce FEV₁ 7

Practical Implementation Algorithm

1. Teach huffing technique first as the foundation 1
2. Add PEP device (5-20 cm H₂O or T-PEP at 1 cm H₂O) if secretions are copious 1, 3, 4
3. Consider active cycle of breathing or autogenic drainage for motivated patients who can learn these techniques 5
4. Reserve oscillatory devices for patients who fail standard techniques 1
5. Never use manually assisted cough in COPD patients 1, 6

Evidence Limitations

Long-term outcome data on mortality, quality of life, and hospitalization rates for airway clearance techniques in COPD remain unknown. 1, 2

• Most high-quality studies were performed in cystic fibrosis patients, not COPD 1
• Well-powered controlled trials on long-term effects of combined airway clearance techniques in COPD are needed 5
• The modest short-term benefits on sputum clearance have not been proven to translate into improved long-term outcomes 1