A 28-year-old female (55-kg IBW) is being mechanically ventilated with VC-CMV, f = 14/min, VT = 700 mL. The patient has no history of pulmonary disease. The resulting ABG values are: pH 7.55, PaCO2 27 mm Hg, HCO3 23 mEq/L.
The most appropriate action to take is which of the following?
a. Decrease VT to 600 mL.
b. Decrease VT to 450 mL.
c. Decrease f to 12/min.
d. Decrease f to 10/min.
Question 2
A male patient (83-kg IBW) is intubated and ventilated with PC-CMV, f = 12/min, set PIP = 28 cm H2O, resulting in a VT of 430 mL.
The ABG results on this setting are: pH 7.35, PaCO2 45 mm Hg, and HCO3 23 mEq/L. For-ty-eight hours later on the same settings, the ABG results are: pH 7.54, PaCO2 27 mm Hg, and HCO3 21 mEq/L with an exhaled VT of 800 mL. The most appropriate action at this time is which of the following?
a. Decrease PIP to 25 cm H2O.
b. Decrease PIP to 19 cm H2O.
c. Decrease f to 10/min.
d. Decrease f to 8/min.