Respiratory Care Therapeutics: Extubation

Extubation

• Requires 2 people to perform, but in clinical situations, one person can perform extubation, who should be proficient in intubation.
• Patient should breathe unassisted through the tube for a brief period before extubation to assess pulmonary reserve.
• Patient should be physiologically monitored, and emergency equipment and personnel trained in airway management skills should be present.
• Personnel should follow the institute infection control policy.

Definitions

• Extubation: The process of removing an artificial tracheal airway (oral or nasal endotracheal airway).
• Decannulation: Process of removing tracheostomy tube.

Assessing Patient Readiness for Extubation or Decannulation

• Patient should meet established extubation readiness criteria, including:
  • Original problem is no longer present.
  • Quantity and thickness of secretions have decreased.
  • Upper airway patency.
  • Presence of intact gag reflex.
  • Ability to clear airway secretions.
  • Adequate respiratory muscle strength (Maximum negative inspiratory pressure > -30 cm H2O).
  • Vital capacity > 10 ml/kg ideal body weight.
  • Tidal Volume > 5 mL/kg.
  • In adults, spontaneous exhaled minute ventilation < 10 L/min.
  • Capacity to maintain appropriate pH (pH ≥ 7.25) and arterial partial pressure of CO2 during spontaneous ventilation.
  • In adults, respiratory rate < 30 breaths/min during spontaneous breathing.
  • Thoracic compliance > 25 ml/cm H2O.
  • Work of breathing < 0.8 J/L.

Spontaneous Breathing Trial (SBT)

• SBT should be performed for 30-120 minutes with low level of CPAP (or PEEP) (e.g., 5 cm H2O) or low level of pressure support (e.g., 5-7 cm H2O).
• Patient should show improved gas exchange (ABG); PaO2 ≥ 60 mm Hg FiO2 ≤ 0.40 on PEEP ≤ 5 cm H2O.
• Hemodynamic stability.
• RSBI (rapid shallow breathing index): RR/Vt < 105.
• Subjective comfort.

Post-Extubation Complications

• Hoarseness, sore throat, and cough are common but benign complications.
• Laryngospasm is a rare but serious complication that can occur after extubation.
• Extubation failure is defined as reinsertion of the airway due to airway problems within 48 hours after extubation.
• Hypoxemia and hypercapnia can occur after extubation due to various reasons.

Predicting Difficult Extubation

• Cuff-leak test can predict difficult extubation.
• A positive cuff-leak test (absence of leak or leak less than 15%) indicates a high risk of upper airway obstruction.

Risk Factors for Extubation Failure

• Extubation failure means the need for reintubation within 48 h after extubation.
• Risk factors include:
  • Tracheal intubation > 48 h.
  • Upper airway obstruction.
  • Edema.
  • Stridor and/or reintubation.
  • Other factors that can lead to extubation failure.