How can a patient simulate intermittent positive pressure breathing (IPPB) without a machine?

Manual Techniques to Simulate IPPB Without a Machine

Patients can simulate IPPB effects through air stacking (breath stacking), glossopharyngeal breathing, and manually assisted coughing—techniques that increase lung volume and improve airway clearance without requiring mechanical devices. 1

Air Stacking (Breath Stacking)

This is the most practical technique for simulating positive pressure breathing at home. The patient takes a series of consecutive tidal breaths without exhaling between them, progressively filling the lungs to maximum capacity. 1

How to Perform:

• Take a normal breath in and hold it with a closed glottis (hold your breath)
• Without exhaling, take another breath in and hold it
• Repeat this 3-5 times until the lungs feel maximally inflated
• Hold the final deep breath for 3-5 seconds
• Exhale slowly and completely 1

Clinical Benefits:

• Improves maximum insufflation capacity (the maximum air volume that can be held with a closed glottis) 1
• Increases range of motion of the lung and chest wall 1
• Aids in assisted coughing by increasing the volume of expelled air 1
• Particularly effective for patients with neuromuscular weakness 1

Glossopharyngeal Breathing (GPB)

This technique uses oral and pharyngeal muscles to force air into the lungs, essentially "gulping" air. 1

How to Perform:

• Close the glottis
• Use the tongue, cheeks, and pharyngeal muscles to push small boluses (gulps) of air past the vocal cords into the lungs
• Each "gulp" delivers approximately 40-200 mL of air
• Perform 6 or more consecutive gulps to produce a full tidal volume breath 1

Clinical Applications:

• Allows short periods off mechanical ventilation for patients who typically require support 1
• Useful as a backup technique in the event of ventilator failure 1
• Requires intact oropharyngeal and laryngeal muscle strength 1

Deep Breathing Exercises with Breath Holding

Supervised deep breathing exercises are equally effective as IPPB for preventing postoperative pulmonary complications. 2

Technique:

• Take a slow, deep inspiration to maximum capacity
• Hold the breath for 5 seconds
• Exhale slowly using pursed-lip technique (exhaling through nearly closed lips) 3
• Repeat 10-15 times per session, 4 times daily 2

Evidence Base:

• Deep breathing exercises reduced pulmonary complications from 48% (control) to 22% (p<0.05) after abdominal surgery 2
• No significant difference in effectiveness compared to mechanical IPPB 2
• Avoids the 18% side effect rate associated with mechanical IPPB 2

Incentive Spirometry as an Alternative

While not identical to IPPB, incentive spirometry provides visual feedback for sustained maximal inspiration and is more practical than mechanical IPPB. 2, 4

Key Points:

• Encourages sustained maximal inspiration (SMI) to open atelectatic lung areas 3
• Equally effective as IPPB in preventing postoperative complications (21% vs 22% complication rates) 2
• Significantly shorter hospital stays compared to controls (8.6 vs 13 days for upper abdominal surgery) 2
• Can be improvised using a simple paper-blowing device that correlates with vital capacity 3

Manually Assisted Coughing (Augmentation Technique)

This combines inspiratory assistance with forced expiratory augmentation to simulate the full IPPB cycle. 1

Technique:

1. Inspiratory Phase: Use air stacking or glossopharyngeal breathing to maximize lung inflation 1
2. Expiratory Phase: A caregiver pushes firmly on the upper abdomen or chest wall in synchrony with the patient's cough effort 1
3. Repeat 3-5 times per session during respiratory infections or when secretion clearance is needed 1

Clinical Indications:

• Most beneficial when peak cough expiratory flow is <270 L/min 1
• Essential when maximal expiratory pressure is <60 cm H₂O 1
• Critical during respiratory infections when muscle function deteriorates 1

Critical Pitfalls to Avoid

• Do not attempt these techniques during acute respiratory distress without medical supervision—they require adequate respiratory muscle strength 1
• Air stacking requires intact glottic function—patients with bulbar weakness may not be able to hold air effectively 1
• Glossopharyngeal breathing requires training—it is not intuitive and needs instruction from a respiratory therapist 1
• Manual chest/abdominal thrusts must be synchronized with the patient's cough effort to avoid injury 1
• These techniques do not replace mechanical devices when peak cough flows are <160 L/min, as mechanical insufflation-exsufflation is superior in this range 1

When Manual Techniques Are Insufficient

Mechanical devices become necessary when manual techniques fail to maintain adequate airway clearance or when respiratory muscle weakness is severe. 1

Specific Thresholds:

• Peak cough expiratory flow <160 L/min indicates ineffective airway clearance requiring mechanical assistance 1
• Mechanical insufflation-exsufflation is superior to breath stacking or manual cough assistance for generating peak cough flows 1
• Particularly important when scoliosis prevents optimal use of manual assisted cough 1

Practical Implementation Algorithm

1. Start with air stacking 4 times daily as the primary technique 1, 2
2. Add glossopharyngeal breathing if the patient can learn the technique and needs additional support 1
3. Incorporate deep breathing exercises with breath holding for 15 minutes, 4 times daily 2
4. Use manually assisted coughing during respiratory infections or when secretions are difficult to clear 1
5. Monitor effectiveness using pulse oximetry during respiratory illnesses 1
6. Escalate to mechanical devices if peak cough flows fall below 160-270 L/min 1