In which clinical situations is intermittent suctioning indicated for patients with endotracheal tubes or tracheostomies who are unable to clear secretions?

When is Intermittent Suctioning Required?

Intermittent endotracheal or tracheostomy suctioning should be performed only when secretions are clinically present—not on a routine schedule—as evidenced by visible secretions, audible secretion sounds (coarse crackles or "rattling"), increased peak airway pressures, decreased tidal volumes, oxygen desaturation, or patient respiratory distress. 1

Clinical Indicators for Suctioning

Suction only when assessment reveals:

• Visible secretions in the airway or bubbling in the endotracheal/tracheostomy tube 2
• Audible secretion sounds such as coarse crackles or gurgling during breathing 3, 1
• Increased peak inspiratory pressures or decreased tidal volumes on the ventilator 3
• Oxygen desaturation that is clinically significant 1
• Patient signs of respiratory distress including increased work of breathing, agitation, or ineffective cough 3, 4

The American Association for Respiratory Care strongly recommends against routine, scheduled suctioning in favor of assessment-based suctioning to minimize patient exposure to complications including hypoxemia, cardiovascular instability, atelectasis, and tracheal mucosal injury. 1

Frequency Considerations

For Oropharyngeal Suctioning

• Minimum frequency of every 4 hours is recommended for orally intubated patients to prevent accumulation of secretions above the endotracheal tube cuff, which increases ventilator-associated pneumonia risk 5
• Patients with higher secretion volumes (>11 mL at 2-hour intervals) require more frequent assessment and suctioning 5

For Endotracheal/Tracheostomy Suctioning

• No fixed schedule—suction only when clinical indicators are present 3, 4, 1
• The outdated practice of routine hourly or every-2-hour suctioning exposes patients to unnecessary complications without benefit 3, 4

Critical Technique Requirements

When suctioning is indicated:

• Complete the procedure in less than 15 seconds to minimize hypoxemia and atelectasis 2, 3, 1
• Make an initial pass immediately when secretions are visible or audible—do not deliver hyperinflation breaths first, as this forces secretions distally into smaller airways 2
• Use pre-oxygenation with FiO₂ 1.0 if the patient has clinically important oxygen desaturation with suctioning 2, 1
• Apply suction pressure of 80-100 mmHg for pediatrics, up to 200 mmHg for adults 2
• Use a catheter that occludes less than 50% of the endotracheal tube lumen in adults and children, and less than 70% in infants 1

Special Populations Requiring Caution

Brain Injury Patients

• Suctioning increases intracranial pressure and mean arterial pressure transiently, though cerebral perfusion pressure typically remains stable 2, 6
• Use minimal necessary suctioning interventions and monitor closely 2, 6

Patients with Thick vs. Thin Secretions

• For thin secretions, use rapid technique with adequate vacuum pressure rather than interventions to further thin secretions 2
• For thick secretions, proper humidification is the priority—never use routine saline instillation, which decreases oxygen saturation, increases contamination risk, and does not effectively thin mucus 2, 6, 3, 1

Common Pitfalls to Avoid

• Never suction on a fixed schedule without clinical assessment 3, 4, 1
• Never instill normal saline routinely—this practice worsens oxygenation and has no benefit for secretion clearance 2, 6, 3, 1
• Never deliver hyperinflation breaths when secretions are bubbling in the tube—suction first to avoid forcing secretions peripherally 2
• Avoid prolonged suctioning beyond 15 seconds, which significantly increases complications 2, 3, 1

Subglottic Suctioning Caution

• Automated intermittent subglottic aspiration can cause tracheal mucosal invagination and injury in patients with few oropharyngeal secretions 7
• A critical volume of fluid must be present in the oropharynx for safe aspiration 7