Table 1.

Criteria Used to Conclude a Spontaneous Breathing Trial

Physiologic signs of spontaneous breathing trial failure

Increase in heart rate by ≥ 30 beats/min above resting, or heart rate 80% of age-predicted maximum

Systolic blood pressure > 180 mm Hg or < 90 mm Hg

SpO2 sustained < 90% for ≥ 5 min

Breathing frequency > 35 breaths/min for ≥ 5 min

Serious dysrhythmia

Evidence of impending fatigue: accessory muscle use, substernal retraction, sternocleidomastoid activation, paradoxical breathing, nasal flaring

Diaphoresis, pallor changes

Patient felt unable to continue, requested assisted ventilation