A 4-year-old with Fontan circulation is undergoing a tonsillectomy. Shortly after beginning the procedure, the SpO2 decreases from 95% to 82%. Which of the following is MOST likely to improve this patient’s SpO2?


A) Add PEEP
B) Administer metoprolol
C) Allow the child to breathe spontaneously
D) Initiate a milrinone infusion