Suctioning and manual hyperinflation (bagging)

1What it is

Suctioning removes secretions from the airway with a catheter attached to negative pressure, when the patient cannot clear them by coughing.

Shallow suction passes the catheter only to the length of the tube; deep suction goes until resistance is felt, then pulls back about 1 cm before suction. Use shallow suction routinely and deep suction only when shallow suction does not work (AARC 2022).

2Indications

Suction only when there are signs of secretions, not on a fixed schedule:

• Secretions seen or heard in the tube; coarse crackles over the trachea and main bronchi.
• A saw-tooth pattern on the ventilator's flow graph; rising peak pressure (volume modes) or falling tidal volume (pressure modes).
• Falling SpO₂ or worsening blood gases that are likely due to secretions.
• A weak or absent cough after other airway clearance has moved secretions up; suspected aspiration.
• To take a sputum sample.

3Contraindications and precautions

Suction has no absolute contraindication when an artificial airway is blocked. Take extra care in:

• Raised intracranial pressure: extra sedation as prescribed, short passes, few passes.
• High PEEP or FiO₂, severe hypoxaemia: closed suction, pre-oxygenate.
• Bleeding risk: low platelets or clotting problems, fresh haemoptysis: gentle, shallow suction.
• Unstable heart rhythm or BP; spinal cord injury or GBS (vagal bradycardia).
• Bronchospasm (suction can trigger it).
• Recent lung resection: no deep suction near the bronchial stump.
• Nasal route not used with a base-of-skull fracture or CSF leak, facial fractures, nasal bleeding or blocked nasal passages, and used with care in stridor (laryngospasm).

4Procedure (endotracheal, open)

1. Assess and explain: need for suction, vital signs, SpO₂; tell the patient (even if sedated) what you will do.
2. Prepare: hand hygiene, apron, eye protection, sterile glove on the dominant hand; check the suction pressure; choose the catheter size.
3. Pre-oxygenate if the patient drops their SpO₂ with suction (raise FiO₂ briefly, often for 30–60 seconds, using the ventilator's oxygen button).
4. Insert the catheter without suction to the planned depth (shallow: tube length).
5. Withdraw with suction applied, rolling the catheter between the fingers, in under 15 seconds.
6. Reconnect the ventilator at once; let SpO₂ and heart rate recover before another pass; usually no more than 2–3 passes.
7. Oral suction last, with a separate catheter or Yankauer (never go from the mouth into the tube).
8. Reassess and record: breath sounds, SpO₂, amount, colour and thickness of secretions, any bleeding, how the patient tolerated it.

• No routine saline down the tube: it does not thin secretions well and may raise infection risk. Thick secretions need better humidification and hydration.
• With a closed system, advance the catheter through the sleeve, suction while withdrawing, then flush the catheter.

5Hazards and complications (3 marks in W16, S17, S18, W19, S26)

6Manual hyperinflation ("bagging") (7 marks in S22 and S24)

Manual hyperinflation (MHI) means disconnecting the ventilator and giving larger, slower breaths with a rebreathing bag, followed by a quick release. It imitates a cough.

Aims

• Re-open collapsed alveoli (air passes behind secretions through collateral channels).
• Move secretions towards the large airways: the quick release creates a fast expiratory flow.
• Improve lung compliance and oxygenation for a short time.

Technique

1. Two-person technique is common: one bags, one applies chest shaking or vibration.
2. A 2-litre bag with oxygen at about 15 L/min, a pressure manometer and a PEEP valve if the patient needs PEEP.
3. Patient in side-lying with the affected area uppermost (or supine).
4. Slow, deep inspiration (larger than the ventilator breath), an inspiratory hold of about 2–3 seconds, then a quick release of the bag so the patient breathes out fast; add vibrations or shaking during that expiration.
5. Keep the peak airway pressure at about 40 cmH₂O or less on the manometer.
6. Repeat a few breaths in sets, suction when secretions reach the large airways, then reconnect and reassess.

Contraindications and precautions

• Undrained pneumothorax (absolute); bullae; recent lung surgery with a fresh bronchial stump.
• Unstable BP or arrhythmia (large breaths reduce venous return).
• High PEEP (above about 10) or high FiO₂: disconnection collapses the lung.
• Raised intracranial pressure not under control; severe bronchospasm; frank haemoptysis; pulmonary oedema.

7Exam corner

Past questions (MUHS, 2016–2026)

• 7-mark questionsSuctioning and bagging: indication, procedure and precautions (S22). Suctioning and manual hyperinflation: procedure, indication and precaution (S24).
• 3-mark questionsHazards of suctioning (W16, S18, S26). Any six complications of suctioning (S17). Complications with suctioning (W19).

Answer skeleton: suctioning and bagging, 7 marks

1. [1] Definitions: suction, open and closed, shallow and deep; manual hyperinflation.
2. [1.5] Indications for each.
3. [3] Procedure: suction steps with the three numbers; MHI technique (slow breath, hold, quick release, 40 cmH₂O).
4. [1.5] Precautions and contraindications; hazards.