A blood culture would be in order at this point. The fever and rash are most likely signs of some kind of illness or some kind of allergic reaction. A blood culture and subsequent blood tests would prove or disprove it. A blood sugar check would help if she were light headed, dizzy, but not if she’s already unconscious with a fever.
The CT scan would help if she complained of head pains or of other head-related issues. Arterial blood gas tests show how much of what kind of various gases are showing up in the blood. Since she’s assumed to be breathing just fine (the question states nothing about breathing issues, just a fever and a rash), there’s no need to test her gas levels.
