Airway Clearance and Suctioning

In depth

The one-page summary above is what the PDF prints. These sections go further.

Why secretions are retained

Clearance depends on cilia, a mucus layer of the right thickness, and a cough with enough flow. Cough needs a deep breath, glottic closure, then expiratory muscles that build pressure and release it as a high-velocity jet. Neuromuscular weakness fails at the inspiratory and expiratory steps, bulbar weakness at glottic closure, and CF, bronchiectasis and smoke injury at the mucus itself. An artificial airway prevents glottic closure, so even strong patients cough poorly through a tube.

AARC 2013 found little high-level evidence for nonpharmacologic airway clearance in hospitalized patients without CF. It recommends cough assistance in neuromuscular disease, especially when peak cough flow is under 270 L/min, early mobility after surgery, and no routine chest physiotherapy for pneumonia, COPD or after surgery. CPT, PEP, IPV and chest wall oscillation could not be recommended in neuromuscular disease for lack of evidence. In CF (Flume 2009) airway clearance is recommended for everyone, no technique beats another, and aerobic exercise is a useful adjunct.

Postural drainage positions and technique

Percussion is rhythmic clapping with cupped hands over the segment being drained, through a thin layer of cloth, avoiding bone prominences, breasts and incisions. Vibration is a fine tremor applied in the direction the chest moves on exhalation. Neither has proven superior to the other or to mechanical devices. Monitor SpO₂, heart rate, breath sounds, sputum volume and color, and ICP where measured.

Positive expiratory pressure and devices

PEP keeps small airways open during exhalation so that air gets behind secretions and collateral channels refill, then huffing moves the mucus up. The patient breathes in a slightly larger than normal breath, holds 2–3 seconds, and exhales actively but not forcefully through the resistor for 10–20 breaths, aiming for 10–20 cm H₂O on a manometer, then huffs; 4–6 cycles take 15–20 minutes. Oscillating devices add flow interruptions: the Flutter's steel ball depends on gravity and works only upright, while lever-type devices (Acapella, Aerobika) work in any position.

Chest wall oscillation vests compress the chest at about 5–20 Hz, usually stepping through several frequencies for 20–30 minutes with pauses to huff; nebulized drugs can be given at the same time. Intrapulmonary percussive ventilation delivers small high-rate bursts with aerosol by mouthpiece or into a ventilator circuit. Insufflation–exsufflation gives a deep positive breath then a rapid shift to negative pressure, often around +40 and −40 cm H₂O for 2–3 s and 1–2 s, in sets of 4–5 with rest, followed by suctioning if needed; higher pressures may be needed through a tracheostomy.

Huffing (forced expiratory technique) is one or two open-glottis exhalations from mid to low lung volume. The active cycle of breathing alternates breathing control, 3–4 deep breaths with a hold and huffs. Autogenic drainage moves secretions by breathing at low, then middle, then high lung volumes. Manually assisted cough, an abdominal thrust timed to the cough, helps spinal cord injury but is avoided after abdominal surgery.

Suctioning technique and complications

AARC 2022 lists breath sounds, secretions seen in the tube and a sawtooth ventilator waveform as indications in children and adults, and a sudden rise in airway resistance in neonates; suction as needed, not on a schedule. Preoxygenate children and adults, use sterile technique for open suction, keep each pass to 15 seconds or less, and use shallow suctioning (to the tip of the tube) unless it fails. Saline instillation does not thin secretions and can cause desaturation and spread contamination.

Complications include hypoxemia, atelectasis from the vacuum, bradycardia from vagal stimulation, tachyarrhythmias, bronchospasm, mucosal trauma and bleeding, raised ICP, and infection. Closed in-line systems avoid disconnection and derecruitment and protect staff; with high PEEP, a patient who desaturates every time the circuit is opened needs a closed system and, if derecruitment occurs, a recruitment maneuver. A catheter that will not pass through a tracheostomy means the tube is blocked or displaced, an emergency covered on the Ventilator Liberation and Tracheostomy page.

Nasotracheal suctioning (AARC 2004) clears patients without an artificial airway who cannot cough secretions out. A nasopharyngeal airway protects the nose with repeated passes. Contraindications are relative except epiglottitis or croup (absolute): occluded nasal passages, nasal bleeding, acute head, facial or neck injury, coagulopathy, laryngospasm, irritable airway, upper respiratory infection, tracheal or high gastric surgery, myocardial infarction and bronchospasm.

When to hold therapy

• Hemoptysis in CF (Flume 2010): continue airway clearance for scant bleeding (under 5 mL); stop it, and hold hypertonic saline, for massive bleeding (over 240 mL in 24 hours), and consider bronchial artery embolization.
• Non-massive hemoptysis outside CF: pause vigorous clearance and irritant aerosols while the source is found.
• Untreated pneumothorax: no PEP, IPPB or insufflation–exsufflation until a drain is in place.
• Lobar collapse that persists after a day of clearance and suctioning with worsening gas exchange: therapeutic bronchoscopy. Routine bronchoscopy for secretions is not recommended.
• No response after a fair trial: stop and record why, rather than continuing on a schedule.