#47 Extubation: Tube Be or not Tube Be
On this week's episode of Critical Care Time, Nick & Cyrus tackle extubation. Join them for a pragmatic, soup-to-nuts approach on liberation from mechanical ventilation. You'll learn about the pre-extubation assessment, pitfalls and pears of the RSBI, who benefits from extubation to positive-pressure support and so much more! Give us a listen and let us know what you think! Be sure to head over to www.criticalcaretime.com for show notes on this episode and many of our other recordings!
We need to talk (more) about extubation
We discuss intubation 5x more often than extubation — but liberation from mechanical ventilation is a critical moment for patient outcomes. Everyday that someone remains intubated comes with a risk of delirum, infection, and other complications. It’s also a day that they can’t speak, can’t eat, and often have limited mobility.
To quantify our bias towards intubation:
PubMed Search Results:
Intubation: ~106,519 articles
Extubation: ~19,088 articles
FOAMed Content:
Podcasts mentioning "Intubation": 3,751
Podcasts mentioning "Extubation": 535
Extubation Vocabulary:
Weaning → Liberation:
"Weaning" implies gradual withdrawal. "Liberation" captures the urgency and importance.
Spontaneous Breathing Trial (SBT):
Daily test of readiness to liberate from mechanical ventilation.
Failure:
Not "patient failed" — "we failed to successfully extubate." (it’s our job!)
Why early extubation is so important
Prolonged intubation risks:
Ventilator-associated pneumonia (VAP):
Risk: ~1–3% per day initially (3% per day for the first 5 days, 2% for the next week, and 1%/day thereafter.)
Attributable mortality: ~15%
ICU-Acquired Weakness and Myopathy:
Muscle loss: 2–3% per day
Diaphragm atrophy: up to 6% per day
Delirium:
Every day of mechanical ventilation substantially increases delirium risk: 10-20% increased risk of developing delirium for each additional day of mechanical ventilation.
Delirium is associated with 3x increased 6-month mortality (Ely et al., NEJM, 2004), as well as increased ICU and hospital LOS, decreased functional status after discharge, and increased hospital costs.
Extubation readiness is not just about lung function — it requires assessment of:
Underlying illness resolution
Mental status
Secretions management
Cuff leak / airway edema
Respiratory mechanics and strength
Hemodynamic stability
Adequate gas exchange
In general it is better to try exubation and reintubate than to delay unnecessarily:
Ideal reintubation rate ≠ 0%
A culture of over-caution results in longer mechanical ventilation and worse outcomes.
The extubation process
Spontaneous Breathing Trial (SBT)
Daily SBT Criteria:
FiO₂ ≤ 0.5
PEEP ≤ 8 cm H₂O
Awake enough to follow commands (usually)
Manageable secretions
Common SBT Methods:
Low-Level Pressure Support (e.g., 5 over 5) - low level pressure support to overcome the added resistance of the ETT
Automatic Tube Compensation (ATC) - precisely calibrated pressure support to exactly match the added resistance of the ETT
CPAP Trial (e.g. “0 over 5”) - no pressure support, but some CPAP provided
T-piece Trial - no pressure support or CPAP provided. The hardest method for breathing trials. Rarely used now, but was used in much of the extubation literature.
Sedation strategy:
Full sedation off preferred
Light sedation (dexmedetomidine, ketamine) may be needed
Monitoring During SBT
0. Is the problem resolved (or at least resolving)?
Look at the Patient:
Do they look bad?
Diaphoresis, nasal flaring, accessory muscles are signs of distress
Anxiety may be due to work of breathing or inadequate sedation. Consider coaching.
Look at the Monitor:
Are there significant physiological derangements?
Hypoxia (SpO₂ < 90%), Arrhythmias, tachy/bradycardia, BP changes
Look at the Ventilator:
Is the breathing adequate?
Tidal Volume (TV): >200 mL
Respiratory Rate (RR) < 30 bpm
Minute Ventilation (MV)
MV = TV x RR
Normal: 5-6 L/min
Too low is likely inadequate. too high may not be sustainable,
Exceptions:
Some people may normally have low TV and high RR (e.g. severe kyphoscoliosis); in this case ask “are they back to baseline?”
Some people may need more MV (e.g. resolving DKA); 6 lpm may be inadequate for them. Always contextualize.
Rapid shallow breathing index (RSBI)
RSBI = RR / TV (in liters)
RSBI > 105 associated with failure, however there are many limitations to this study.
Small, old, single center trial, using outdated methodology (T-piece trial).
Subsequent meta-analysis suggest performance is only mid.
In one large pooled meta-analysis, RSBI had only moderate sensitivity (83%) and pretty poor specificity (58%) suggesting both that patients who are truly ready for extubation might be missed if RSBI alone is used and that a significant number of patients with "acceptable" RSBI values (<105) may still fail extubation.
Look at Blood Gas:
One study found that in 93% of cases, ABG did not change extubation decisions. That said, it might have been very useful in 7% of cases…
It’s worth noting, that a low HCO3 (< 18) is associated with a higher risk reintubation.
It’s therefore reasonable to check a blood gas if fast and easy (as it most ICUs)
VBG sufficient for most; Arterial preferred if acidosis or hypercapnia
Check for air leak
Deflate balloon and see if air escapes around the ETT. Used to asses for glottic edema.
Extubation cases
Case 1: No Cuff Leak
Deflate cuff, measure leak (use vent scalars or listen)
Treatment with steroids per protocol reduces post extubation stridor (but maybe not rate or reintubation)
Dexamethasone 5–10 mg IV q6h × 2–4 doses; can usually extubate successfully after 6-12 hours.
Also consider diuresis, elevate head of bed
Case 2: Severe Agitation
Coach, reassure, optimize environment; can use family.
Dexmedetomidine or low-dose ketamine are useful adjuncts
Consider "ninja extubation" concept if necessary - turn off sedation and quickly extubate before patient becomes agitated.
Case 3: Too Weak
Strength testing (MRC Scale, handgrip)
Early mobilization, nutrition optimization
Use HFNC or NIV post-extubation
Consider tracheostomy if needed
Case 4: Lots of Secretions
Chest physiotherapy, mucolytics (NAC, hypertonic saline)
Aggressive hydration
Evaluate cough strength (peak cough flow)
Swallow evaluation
Case 5: Wouldn’t Want to Be Reintubated
Bias toward extubation
Extubate to HFNC or NIPPV as needed
Discuss Goals of Care (GOC) clearly
Case 6: Failed Extubation x2
Increase SBT threshold (e.g., CPAP trial 60–90 min)
Consider trach if repeated failures
Balance optimism with realism
Case 7: Heart Failure
Zero PEEP trial —> assess physiological effects of being off positive pressure
Aggressive diuresis
Extubate to NIPPV
Reference:
HIGH-WEAN trial: HFNC + NIPPV reduced reintubation in high-risk patients (Thille et al., AJRCCM, 2019)
Case 8: Self-Extubation
Approach reintubation as potentially difficult:
Smaller ETT
Video laryngoscopy
Bougie on hand
Potentially serious complication, however most will do just fine; 80% do not require reintubation within 24 hours.
🎧 Related Past Episodes:
#4: Delirium with Dr. Wes Ely
#21: ICU Nutrition and Myopathy with Dr. Paul Wischmeyer
#43: ICU Mobility with Kali Dayton
🙏 Sponsors:
SeaStar Medical
The Difficult Airway Company
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HIGH-WEAN
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#4: Delirium with Dr. Wes Ely
#21: ICU Nutrition and Myopathy with Dr. Paul Wischmeyer
#43: ICU Mobility with Kali Dayton
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Chastre J, Fagon JY. Ventilator-associated pneumonia. N Engl J Med. 2002;346(8): 512-519.
Ely EW, et al. Delirium in mechanically ventilated patients. JAMA. 2001;286(21): 2703-2710.
Levine S, et al. Rapid disuse atrophy of diaphragm fibers in mechanically ventilated humans. N Engl J Med. 2008;358(13): 1327-1335.
De Jonghe B, et al. ICU-acquired paresis. JAMA. 2002;288(22): 2859-2867.
Yang KL, Tobin MJ. A prospective study of indexes predicting the outcome of trials of weaning from mechanical ventilation. N Engl J Med. 1991;324(21): 1445-1450.
Thille AW, et al. High-flow nasal cannula oxygen therapy vs non-invasive ventilation post-extubation in high-risk patients. Am J Respir Crit Care Med. 2019;199(5): 620–629.
Wang F, et al. Effect of prophylactic dexamethasone on the incidence of postextubation stridor and reintubation. Crit Care Med. 2006;34(5): 1345-1353.
Girard TD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomized controlled trial. Lancet. 2008;371(9607): 126-134.