A middle-aged G3P2 presents at 19wks gestation c/o abd pain that started early this AM. She had some nausea but no vomiting, a subjective fever and no loose or frequent stools. Your differential is broad but at the top is appendicitis. You d/w OB/GYN and radiology. You all agree that the patient needs imaging to eval for an appendicitis; you need to have a R/B/A conversation with the patient. What will you say?
Try a sono first; if it’s inconclusive, you need to move on, as the risk of a perforated/appy is more immediate than the radiation to the patient and the fetus.
The highest risk of teratogenesis of a CT abd/pelv is 3-15weeks. She is outside of the window now.
The teratogenesis risk (<1%) is appreciated at 5rads or higher; <5rads are absorbed from CT abd/pelv for appendicitis (it’s about 3rads in the 2nd and 3rd tri’s and 2.4rads in the 1st tri).
Consider an MRI of the abd/pelv to mitigate this low risk of teratogenesis and the unclear carcinogenic risks.
Ref: http://blog.ercast.org/2011/11/rlq-pain-in-pregnancy/ (Listen and read)