Table 5—

Considerations for assessing readiness to wean

Clinical assessmentAdequate cough
Absence of excessive tracheobronchial secretion
Resolution of disease acute phase for which the patient was intubated
Objective measurementsClinical stability
 Stable cardiovascular status (i.e. fC ≤140 beats·min−1, systolic BP 90–160 mmHg, no or minimal vasopressors)
 Stable metabolic status
Adequate oxygenation
Sa,O2 >90% on ≤FI,O2 0.4 (or Pa,O2/FI,O2 ≥150 mmHg)
 PEEP ≤8 cmH2O
Adequate pulmonary function
fR ≤35 breaths·min−1
 MIP ≤-20– -25 cmH2O
VT >5 mL·kg−1
 VC >10 mL·kg−1
fR/VT <105 breaths·min−1·L−1
 No significant respiratory acidosis
Adequate mentation
 No sedation or adequate mentation on sedation (or stable neurologic patient)
  • Data taken from 5, 6, 13, 1618, 22. fC: cardiac frequency; BP: blood pressure; Sa,O2: arterial oxygen saturation; FI,O2: inspiratory oxygen fraction; Pa,O2: arterial oxygen tension; PEEP: positive end-expiratory pressure; fR: respiratory frequency; MIP: maximal inspiratory pressure; VT: tidal volume; VC: vital capacity. 1 mmHg = 0.133 kPa.