What is the Sharia ruling on the death of a kidney failure patient after undergoing a contrast CT scan, given that a female doctor neglected to warn other doctors about the danger of this scan, and is she sinful for that?

If the doctors are rotating in attendance on the patient, and the results of the medical analyses are available in her file, then the responsibility falls on the doctor who ordered the X-ray without thoroughly checking the patient's file. This is considered an error, not an intentional act. The feeling of responsibility on the part of the questioner's wife is commendable, but it should remain within the limits acceptable by both Sharia and reason.