Active Cycle of Breathing Techniques (ACBT)
The Active Cycle of Breathing Techniques (ACBT) is a structured airway clearance method designed to mobilize and clear excess pulmonary secretions. It combines relaxed breathing, deep chest expansion exercises, and huffing to improve lung ventilation and clear mucus without causing airway collapse.
- 1Step 1: Breathing Control - Rest one hand on your stomach and breathe gently through your nose and out through your mouth, relaxing your upper chest and shoulders for 20-30 seconds.
- 2Step 2: Thoracic Expansion - Take 3 to 4 deep, slow breaths in through your nose, expanding your lower ribs. Hold the inhale for 2-3 seconds, then sigh out gently through your mouth.
- 3Step 3: Breathing Control - Return to gentle, relaxed breathing for another 20-30 seconds to prevent dizziness or airway spasm.
- 4Step 4: Forced Expiration (Huffing) - Take a medium breath in, then forcefully exhale through an open mouth (like fogging a mirror) 1 to 2 times to move secretions upward.
- 5Step 5: Cough and Clear - If you feel mucus ready to clear, cough to expel it. Repeat the entire cycle until your chest feels clear.
ACBT works through a combination of collateral ventilation and airflow mechanics. The Thoracic Expansion Exercises (TEE) utilize collateral channels, such as the pores of Kohn and canals of Lambert, to direct air behind mucus plugs. The Forced Expiration Technique (FET), or huffing, creates an equal pressure point that moves from peripheral to central airways, shearing secretions off the airway walls while preventing the airway collapse often caused by forceful coughing. Interspersed Breathing Control phases prevent bronchospasm and oxygen desaturation.
Treats Symptoms
Target Metrics
Recent thoracic or abdominal surgery, severe bronchospasm, acute rib fractures, untreated pneumothorax, or severe hemoptysis.
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