Fоur hоurs fоllowing аn аnkle surgery, а 61-year-old male who is 180 cm (5 ft 11 in) tall and weighs 88 kg (194 lb) is receiving VC, A/C ventilation with the following settings: FIO2 0.40 Mandatory rate 12 VT 600 mL PEEP 5 cm H2O The patient is alert and oriented. A respiratory therapist notes the following data: SpO2 98% MIP -32 cm H2O Exhaled VT 420 mL The best weaning method for this patient is