Of the following choices, which is the first step that should be considered for the teenaged patient undergoing one-lung ventilation via a double-lumen endotracheal tube who develops hypoxemia?
a) Initiate Nitrous Oxide 50%
b) Apply CPAP to the operative (non-dependent) lung
c) Apply PEEP to the non-operative (dependent) lung
d) Abort one-lung ventilation
e) Increase respiratory rate on the ventilator
Answer b.
Management of the hypoxemic OLV patient includes verifying the presence of 100% oxygen, removing the patient from the ventilator and manually ventilating the patient, checking the circuit for air leaks, and verifying the correct positioning of the endotracheal tube. If hypoxemia persists, the addition of CPAP to the non-ventilated, operative lung often resolves the problem. Somewhat counter-intuitively, PEEP to the ventilated (dependent) lung may decrease saturation by shunting more blood to the non-ventilated lung.