Fig. 2.

Standardized stepwise weaning protocol. (1) Step 1, Clinical stability: absence of organ failure, absence of active sepsis, and hemodynamic stability without vasoactive support. (2) Step 2, De-escalation of support: stepwise reduction toward PSV. (3) Step 3, SBT trigger and conduct: once mode is reduced to PSV with PSV + PEEP ≤16 cmH₂O, a 2-h SBT is performed on PSV with the cuff inflated (minimal support, not full disconnection). (4) Step 4, Stratification by SBT outcome: from SBT passers to HFOT via tracheostomy titrated to SpO₂ ≥95%, with defined objective/subjective failure criteria and daily extension of tolerated duration; from SBT failures to gradual PSV down-titration with repeated SBTs, and, if PSV de-escalation fails on 5 consecutive days, transition to a single-limb portable home ventilator. (5) Step 5, Step-down from HDU to the general ward. (6) Step 6, Decannulation per the department speaking-valve protocol. IMV, invasive mechanical ventilation; PSV, pressure-support ventilation; SBT, spontaneous breathing trials; HFOT, high-flow oxygen therapy; NIV, noninvasive ventilator; HDU, high-dependency unit