How should I wean a hemodynamically stable adult on mechanical ventilation who is on minimal vasopressor support, has adequate oxygenation with FiO2 (fraction of inspired oxygen) ≤0.40, PEEP (positive end‑expiratory pressure) ≤5 cm H2O (PaO2/FiO2 >200 mm Hg), is normothermic, awake, able to protect his airway, and can initiate spontaneous breaths?

Weaning from Mechanical Ventilation

For this hemodynamically stable adult meeting readiness criteria, perform a spontaneous breathing trial using pressure support ventilation at 5-8 cm H₂O with PEEP 5 cm H₂O for 30 minutes, then extubate directly to supplemental oxygen targeting SpO₂ 88-92% if the trial is successful. 1, 2

Daily Readiness Assessment

Before initiating any weaning attempt, confirm the patient meets all of the following criteria:

• Resolution or significant improvement of the primary condition requiring mechanical ventilation 1, 2
• Hemodynamic stability without vasopressor support (your patient meets this with minimal vasopressor support, which should be discontinued or weaned to zero before proceeding) 1, 2
• Adequate oxygenation: FiO₂ ≤0.40-0.50, PEEP ≤5 cm H₂O, PaO₂/FiO₂ >200 mm Hg 1, 2
• Patient arousable and able to follow simple commands (open eyes, squeeze hand) 2, 3
• Intact airway reflexes with adequate cough on suctioning 1, 2
• No new potentially serious conditions or planned procedures in the next 12-24 hours 4, 1

Critical pitfall: Do not attempt weaning if the patient still requires vasopressor support beyond minimal doses—hemodynamic stability is mandatory. 2

Conducting the Spontaneous Breathing Trial

Optimal SBT Technique

Use pressure support ventilation at 5-8 cm H₂O with PEEP 5 cm H₂O rather than a T-piece for the initial trial. This approach achieves superior outcomes: 1, 2

• SBT success rate: 84.6% vs. 76.7% with T-piece 1, 2
• Extubation success rate: 75.4% vs. 68.9% with T-piece 1, 2
• Trend toward lower ICU mortality: 8.6% vs. 11.6% 2

SBT Parameters

• Duration: 30 minutes for standard-risk patients (most failures occur within this timeframe) 1, 2, 3
• FiO₂: Maintain at ≤0.40 during the trial 1, 2
• PEEP: Set at 5 cm H₂O 1, 2

SBT Failure Criteria—Terminate Immediately If:

• Respiratory rate >35 breaths/min or increasing trend 2
• SpO₂ <90% 1, 2
• Heart rate >140 bpm or sustained increase >20% 2
• Blood pressure: Systolic >180 mmHg or <90 mmHg 2
• Increased anxiety or diaphoresis 1, 2
• Use of accessory muscles or abdominal paradox 2
• Altered mental status 1, 3

Risk Stratification for Extubation

Your patient appears to be standard-risk based on the clinical description. However, verify the absence of high-risk features:

High-Risk Criteria (if ANY present, modify post-extubation strategy):

• Age >65 years with multiple comorbidities 1, 2
• Cardiac failure as primary cause of respiratory failure 1, 2
• Failure of more than one prior SBT 1, 2
• Weak cough or excessive secretions 2, 3
• Chronic lung disease (COPD, restrictive disease) 1, 3
• Prolonged mechanical ventilation >14 days 1, 3

Extubation Strategy

For Standard-Risk Patients (Your Patient):

Extubate directly to supplemental oxygen via face mask or nasal cannula, targeting SpO₂ 88-92%. 2

• Monitor SpO₂, respiratory rate, and work of breathing continuously for the first 24 hours 2
• No prophylactic NIV is required for standard-risk patients 2

For High-Risk Patients (If Applicable):

Apply prophylactic noninvasive ventilation (NIV) within 1 hour after extubation rather than standard oxygen therapy. This approach reduces: 1, 2

• Re-intubation risk (RR 0.61; 95% CI 0.48-0.79) 2
• Mortality (RR 0.54; 95% CI 0.41-0.70) 2
• ICU length of stay by approximately 2.5 days 2

Alternative for high-risk patients: High-flow nasal cannula (HFNC) lowers re-intubation rates to 4% vs. 21% with conventional oxygen (P=0.01). 2

Protocol-Driven Implementation

Use a standardized weaning protocol led by respiratory therapists or ICU nurses, with physician sign-off only for the final extubation decision. This approach: 2

• Reduces total mechanical ventilation duration by approximately 25 hours 2
• Shortens ICU length of stay by approximately 1 day 2
• Increases overall weaning success rates 2

Common Pitfalls to Avoid

• Do not delay extubation in patients who pass their first SBT and lack high-risk features—unnecessary delays increase complications 2
• Avoid premature weaning if vasopressor support has not been discontinued or if the primary pathology remains unresolved 2
• Do not skip the cuff-leak test in patients with risk factors for laryngeal edema (female gender, nasal intubation, difficult intubation, prolonged intubation) as post-extubation stridor accounts for 15% of early re-intubations 2
• Monitor closely for the first 24 hours—approximately 10% of patients who pass an SBT will still fail extubation, which is considered an acceptable rate 2

Expected Outcomes

• Extubation success is defined as not requiring re-intubation or NIV within the first 48 hours post-extubation 2
• An extubation failure rate of 5-10% is considered acceptable in contemporary practice 2
• With the pressure-support SBT approach, expect approximately 75% extubation success in standard-risk patients 1, 2