A 53-year-old woman has been intubated for several days after sustaining a right pulmonary contusion after a motor vehicle collision as well as multiple rib fractures. Which of the following is a reasonable indication to attempt extubation?
Negative inspiratory force (NIF) of -15 cm H2O PO2 of 60 mm Hg while breathing 30% inspired FiO2 with a positive end-expiratory pressure (PEEP) of 10 cm H2O Spontaneous respiratory rate of 35 breaths per minute A rapid shallow breathing index of 80