I think Chao’s trip was probably already scheduled and just happened to coincide with Mitch’s medical emergency. The idea that she intentionally fled the country for the purpose of prolonging Mitch’s vegetative existence doesn’t make sense, mostly because I don’t think it was necessary.
That hypothesis is beyond a stretch. First, she is his wife and he is at death's door. Her place is at his side, not sitting around in Beijing. That would be the case whether or not she had a China trip already scheduled.
Second, she owes the American public (most especially Kentuckians) an explanation. If she did not leave the country for the purpose of prolonging Ol' Turtlehead's vegetative existence for strictly political purposes, then she ought to say so. Tell us why you split for China, Elaine.