Spontaneous breathing trial

Definition

• A trial off of vent, or with minimal vent, to assess readiness for extubation/weaning

Indications

• Assess for suitability daily
• Hemodynamic stability
• PaO2/FiO2 > 200 with PEEP ≤ 5cm H2O
• Improvement in the underlying condition

Procedure

• Ventilator switched from full support to minimal support (e.g. pressure support, CPAP, or ventilation with a T-piece)
• Successful if:
  • Patient breathes spontaneously for at least 30 minutes
• Fails if:
  • Resp rate > 35 for more than 5 minutes
  • SaO2 < 90%
  • Heart rate > 140
  • Sustained increase in heart rate by more than 20%
  • Systolic blood pressure > 180 or < 90
  • Rapid shallow breathing index (RSBI) RR/TV > something
  • Increased anxiety or diaphoresis