Airway Clearance Techniques-Postural Drainage, Percussion/Vibration, HFCWO, Suction

Positive Expiratory Pressure (PEP) and High Frequency Chest Wall Oscillation Devices

Overview

• Presentation focuses on positive expiratory pressure (PEP) and high frequency chest wall oscillation devices as adjuncts to foundational airway clearance interventions.

• Highlights the importance of combinations with mobilization, breathing strategies, and therapeutic positioning, especially when postural drainage alone is insufficient.

Positive Expiratory Pressure (PEP) Devices

• Definition: PEP devices help enhance secretion mobilization and maintain airway patency by applying a set positive pressure during exhalation.

• Usage: Can be used independently by patients in conjunction with breathing control, upright positioning, and exercise.

• Mechanism:

  • Applies positive pressure typically between $10$ to $20$ centimeters of water.

  • Prevents airway collapse and promotes movement of mucus toward larger airways.

• One-way Breathing Valve: Utilizes a one-way valve to create resistance via mouthpiece or face mask, allowing effective exhalation against resistance.

• Benefits:

  • Maintains small airway patency.

  • Promotes collateral ventilation.

  • Dislodges mucus obstructions, thus improving gas exchange.

• Standard PEP Session Procedure:

  • Involves a deep breath in, followed by a slow exhalation through the device to maintain pressure.

  • Completion of about $10$ to $20$ breaths, concluded by a huff or cough for expelling mobilized secretions.

Categories of PEP Devices

1. Traditional Low Pressure PEP:

   • Example: TheraPEP system.

   • Delivers smooth resistance with a manometer to ensure the desired therapeutic pressure.

2. Oscillatory PEP (OPEP):

   • Combines resistance with vibratory forces to loosen secretions.

   • Variances:

     • Frequency ranges.

     • Positional requirements.

   • Examples:

     • Flutter Device:

     • Uses a gravity-dependent steel ball; operates effectively when held horizontally; oscillation range between $6$ to $20$ Hz.

     • Acapella Device:

     • Magnetically controlled resistance, gravity-independent, allowing use in any posture; color-coded based on flow requirements (

       • Green model: Flow rates > $15$ liters/minute.

       • Blue model: Flow rates < $15$ liters/minute).

     • Aerobika:

     • Generates higher pressure amplitudes than similar devices.

     • Useful for patients with moderate to severe pulmonary disease.

     • Designed for concurrent nebulized medication delivery.

Clinical Evidence and Outcomes of PEP Therapy

• Clinical Value:

  • Shown to increase sputum production relative to forced expiratory techniques.

  • In some trials, outperformed traditional chest physiotherapy in pulmonary function and patient-reported outcomes.

• Long-term Benefits:

  • Regular usage can reduce hyperinflation, improve expiratory flow rates, and decrease hospitalization frequency in those with chronic pulmonary conditions.

• Patient Suitability:

  • Most effective for those who can generate adequate expiratory flow and follow instructions.

  • Not recommended for individuals with severe neuromuscular impairments or cognitive limitations.

Implementation of PEP Techniques

• Initial Positioning:

  • Ideal: Upright seated posture with back support and elbows resting.

  • Alternative: Reclined position is acceptable except for the flutter device (must be parallel to floor).

• Selecting and Preparing the Device:

  • Options include mouthpiece or face mask; mouthpiece is common but masks may be necessary for children.

  • Nose clips may reduce air escape during use.

• Resistance Setting:

  • Patients instructed to inhale gently, then exhale actively. Adjust resistance gradually aiming for prolonged exhalation (3-4 times inhalation duration).

  • Resistance range: $10$ to $20$ centimeters of water.

• Breathing Cycle:

  • Procedure:

  • Normal-sized breath with diaphragmatic breathing. Hold for 2-3 seconds. Slow exhale through device.

  • Repeat for $10$ to $20$ breaths; 2-3 huffs or forceful coughs afterward to clear secretions.

  • Treatment session duration: Approx. $15$ to $20$ minutes, typically once or twice a day; increased during exacerbations or high mucus production.

  • Devices may have inline ports for supplemental oxygen or aerosolized medications.

  • Alternative for Children: Bubble PEP, using a tube submerged in water for resistance.

• Monitoring and Hygiene:

  • Clinician to monitor for discomfort, dizziness, or changes in respiratory patterns.

  • Important to maintain hygiene: Clean with hot soapy water; follow sterilization protocols in medical facilities.

High Frequency Chest Wall Oscillation (HFCWO)

• Definition: A mechanical airway clearance technique using an inflatable vest connected to an air pulse generator.

• Mechanism:

  • Inflates and deflates to deliver bursts of air between $5$ to $25$ Hertz, creating oscillatory forces that mobilize mucus towards central airways for easier expectoration.

  • Reduces mucus viscosity and elasticity, aiding clearance.

• Applications:

  • Initially developed for cystic fibrosis; used in bronchiectasis, neuromuscular disorders, and secretion-related atelectasis.

  • Ideal for patients with chronic sputum production or impaired cough ability.

• Treatment Protocol:

  • Sessions last about $30$ minutes, performed once or twice daily.

  • Frequency and pressure adjust throughout session to optimize secretion mobilization.

  • Can be used with nebulized bronchodilators/mucolytics for enhanced medication delivery.

• Clinical Evidence:

  • Studies indicate HFCWO can be as effective or more so than conventional chest physical therapy for sputum clearance and pulmonary function enhancement.

  • Associated with potential reduction in hospitalization rates, particularly for chronic respiratory disease patients.

  • Safe for mechanically ventilated patients and well-accepted by pediatric and neurologically impaired populations.

Implementation of HFCWO

• Pre-Treatment Preparation:

  • Familiarize with vest design and fit; should extend to the thigh without restricting breathing.

  • Wear a thin layer under the vest for hygiene; consider shorter vests for patients with abdominal sensitivity.

• Medication: Administer aerosol therapy before using HFCWO for effective delivery.

• Pressure Settings:

  • Adjust to highest comfortable level for effective oscillation, minimizing distress.

• Frequency Variations:

  • Should cycle through different frequencies to enhance mobilization: lower for lung expansion, higher for secretions.

  • Each frequency phase lasts about $10$ minutes, adjustable on patient response.

• Post-Treatment: Encourage patients to cough or huff to clear mobilized secretions post-session.

Conclusion

• Each airway clearance technique reviewed offers unique advantages; no single method is universally superior.

• Important factors influencing airway clearance techniques include:

  • Patient preference.

  • Feasibility.

  • Long-term adherence to treatment.

• Exercise contributes to overall health and should complement airway clearance strategies, enhancing quality of life.

• For patients with specific needs, adjunctive techniques become crucial, especially during exacerbations or when secretion burden is high.

• Adjunctive Strategies:

  • Postural drainage with or without percussion/vibration.

  • Active cycle breathing techniques promote independence but require patient cooperation.

• PEP therapy and mechanical devices like HFCWO have expanded airway clearance options but require proper patient understanding and technique adherence.

• The ideal approach is a hierarchical strategy tailored to individual needs, ensuring maximize likelihood of treatment success through patient-centered care and informed decision-making.

Thank you for the presentation!