Extubation Protocol and Procedure

• Extubation involves removing an oral or nasal endotracheal airway.
• Prolonged tracheal airways increase the risk of pulmonary infection due to aspiration of pharyngeal secretions, contaminated equipment, and ineffective cough.

Introduction to Extubation

• Clinicians should feel confident that a patient can sustain spontaneous ventilation after extubation, usually, if they can tolerate a weaning trial.
  • Consider whether the patient can maintain a patent upper airway post-extubation.
• ET tube removal is performed under controlled conditions.
  • Successful weaning trial.
  • Enteral feeds must be held for ~ 4 hours.
  • Ensure sitting position to extubate.
  • The ET tube, mouth, and upper airway should be suctioned.
• Suction catheters inserted into the ET tube during cuff deflation can catch secretions above the cuff.
• A positive pressure breath using an Ambu Bag can be provided before ET tube removal.
• Supplemental O₂ is provided, titrated to SpO₂, after ET tube removal.
• Patients may have impaired airway protection reflexes after extubation, meaning oral intake should be held.
  • Perform indirect laryngoscopy to assess vocal cord function if speech is impaired > 24 hours post-extubation.

Vocal Cord Paralysis

• Glottic edema and vocal cord inflammation can cause hoarseness and stridor following extubation.
• Vocal cord paralysis is suspected in extubated patients who remain hoarse and exhibit stridor after treatment.

Indications for Extubation

• No single weaning parameter is completely accurate, so multiple should be considered.
• Key requirements include the ability to cough, breathe, and swallow.
• Clinical parameters for extubation include:
  • Resolution/stabilization of the disease process
  • Hemodynamic stability
  • Intact cough/gag reflex
  • Spontaneous respirations
  • Acceptable ventilator settings
• General approaches to extubation include:
  • SIMV (Synchronized Intermittent Mandatory Ventilation) weaning
  • PSV (Pressure Support Ventilation) weaning
  • Spontaneous breathing trials (T-piece) demonstrate superior results.

Cough Assessment

• Target values representing adequate cough:
  • VC (Vital Capacity) greater than 10-15 mL/Kg IBW
  • MIP/NIF (Maximum Inspiratory Pressure/Negative Inspiratory Force) less than -20 to -25 cm H₂O
  • MEP (Maximum Expiratory Pressure) greater than +40 to +60 cm H₂O

Breathing Indicators

• Readiness to breathe is indicated by:
  • Successful Spontaneous Breathing Trial (SBT)
  • Good ABGs (Arterial Blood Gases) on minimal ventilatory support
  • RSBI (Rapid Shallow Breathing Index) less than 105
  • Good VT (Tidal Volume) and respiratory rate (f)
  • Good CLT (Compliance) and RAW (Airway Resistance)

Assessment of Swallowing Ability

• Evaluate the Level of Consciousness (LOC).
• Consider the Glasgow Coma Scale (1-15).
• Perform a Methylene Blue Test to assess speaking and swallowing.

Timing Considerations

• Assess the patient's readiness for extubation.
• Ensure the original problem is no longer present.
• Assess the quantity and thickness of secretions.
• Confirm upper airway patency.
• Check for the presence of an intact gag reflex.
• Ensure the ability to clear airway secretions.
• Assess mental status.
• Verify adequate respiratory, cardiovascular, and metabolic function.

Physiological Parameters Overview

• Spontaneous rate: Less than 35 bpm
• Spontaneous VT: Greater than 4-6 ml/kg
• f/VT (RSBI): Less than 105 breaths/minute/liter
• Minute ventilation: Less than 10 L/min
• MIP (NIF, PIMAX): Less than -20 to -30 mm Hg
• P0.1: Less than 6 cm H₂O
• P0.1/MIP: Less than 0.3
• CROP (Cdyn, f, O₂, Pimax): Greater than 13 ml/breaths/min
• CD: Greater than 25 ml/cmH₂O
• VD/VT: Less than 0.60
• PaO₂: Greater than 60 mmHg (FIO₂ less than 0.40)
• PEEP: Less than 5 -8 cmH₂O
• P/F ratio: Greater than 250 mmHg
• PaO₂/PAO₂: Greater than 0.47
• P(A-a)O₂: Less than 350 mmHg (FIO₂ 100%), 15-60 mmHg
• QS/QT: Less than 20 – 30%

Post-Extubation Distress

• Reintubation can cause serious complications, so predicting its likelihood is important.
• For some patients with high reintubation risk, a tracheotomy may be chosen over attempting extubation.

Common Predictors of Post-Extubation

• Ability to sustain spontaneous ventilation.
• Weaning predictor tests (e.g., f/VT).
• Cuff-leak test results.
• Excessive secretions and ineffective cough.
• Neurologic assessment of the ability to protect the airway.
• Assess spontaneous ventilation.
  • Extubating without assessing the patient's ability to sustain spontaneous ventilation is considered uncommon.
  • (SIMV, Low-level PSV, T-piece trial).
• A weaning trial serves as an additional diagnostic test to predict distress after extubation.
  • The predictive accuracy as a diagnostic test has never been rigorously evaluated.

Cuff-Leak Test

• Some patients recover lung function satisfactorily but develop upper airway obstruction after extubation.
• Direct visualization of the upper airway before extubation is precluded by the presence of the ET tube.
• The volume of air leaking around the ET tube when deflating the cuff is related to the degree of laryngeal obstruction from laryngeal edema.
  • It can test for potential post-extubation swelling that could lead to reintubation.

Performance of Cuff-Leak Test

• Suction the airway and oropharynx first. Deflate cuff, occlude the proximal end of the ET tube, and listen/feel for air leak.
• Record the difference between inspiratory and expiratory tidal volumes with the cuff deflated.
  • A leak of < 110 mL (average of three values on six consecutive breaths) indicates a high risk of post-extubation stridor.
    • It may require treatment with racemic epinephrine or steroids prior to extubation.
• A cuff leak can be measured as a percentage:
  • [(Exhaled VT with cuff inflated – Exhaled VT with cuff deflated)/Exhaled VT with cuff inflated] x 100
  • Patients with a leak of less than 10% are at risk for stridor and reintubation.
    • A positive leak test is "not good," while a negative leak test is "good."
• A successful cuff leak test does not guarantee that post-extubation stridor will not occur.

Time for Extubation

• Think SOAP:
  • Secretions, ensure patient is on minimal Sedation, patient has adequate Spontaneous Tidal Volume (>5ml/kg)
  • Oxygenation less than 40%
  • Airway - Is a maintainable airway expected?, Is there a leak?, Are Steroids indicated?
  • Pressures - PiP less than 25, PEEP less than 5

Post-Extubation Emergencies and Management

• Laryngospasm
• Laryngeal stridor
• Acute hypoxemia
• Acute respiratory failure
• Neurologic pathology

Laryngospasm

• Spontaneous closing of the vocal folds.
• Presents as an absence of air movement, with the patient in a panic (conscious or not).
• Rare, but is a serious complication.
  • Hysteria
  • Mechanical stimulation
  • Chemical
• TX includes high FIO2, sedatives/muscle relaxants, BVM via mask; reintubate if distress is severe or marked.

Laryngeal Stridor

• High-pitched inspiratory noise due to swollen vocal folds.
• Jaw Thrust/Sniff position.
• Secretion clearance.

Treatment of Airway Obstruction

• Nasal/oral airways.
• Mask CPAP.

Treatment Strategies

• Alpha 1 decongestants/vasoconstrictors via SVN: racemic epinephrine 2.25% or levoepinephrine 1:1000.
• Steroids (prior to extubation): prednisone, decadron exert their beneficial effect by inhibition of inflammatory mediators and decreasing capillary permeability.
  • Initial effects take 1-2 hours after IV administration, with maximal effects between 2-24 hours.
• Heliox.
• Cool aerosol via aerosol mask, face tent.

Acute Hypoxemia

• Sudden decrease of oxygen in the arterial blood.
• Increase FiO2 by 10% when extubating if borderline SpO2 is expected
• Caused by secretions/mucous plug (requiring cough or NTS), pulmonary edema, or vomiting/aspiration
• Pulmonary edema can be negative pressure pulmonary edema (due to post laryngospasm), Support with oxygen.
• Patients may suffer cardiac issues (sudden removal of MV), Use Mask CPAP.
• Vomiting/Aspiration
  • Position the patient on their side.
  • Perform oral and NT suction.
  • Support oxygenation.

Acute Ventilatory Failure

• Inability for the patient to ventilate and maintain a normal pH (7.35-7.45).
• Presents with increased RR (Respiratory Rate), increased WOB (Work of Breathing), and decreased SaO2/SpO2.
• Treatment includes NPPV (BIPAP & HFNC), Sedation withdrawal (sedation vacation before extubation), or re-intubation.

Neurologic Pathology

• Neurologic pathologies include: ALS, Traumatic Brain Injury, MS, Guillain Barre, and Critical Illness Neuromyopathy.

Preparation for Extubation

• Do not treat extubating as routine.
• Assess frequently.
• Keep difficult intubation supplies readily available.
• Don't panic.

Basic Post-Extubation Management

• Severe Distress: Reintubate.
• Moderate distress/stridor: Cool mist with oxygen, racemic epinephrine, heliox, steroids, prior to extubation if the patient is suspected to have airway inflammation.
• Mild distress/stridor, sore throat: Cool mist with oxygen, racemic epinephrine, B₂ Agonist if caused by bronchospasm.