Before the study begins, research personnel will do the following to be sure that patients can be in the study:
* research personnel will talk to the treating physician.
* research personnel will review the patient medical records, blood and urine tests already done for as usual medical care, and chest X-ray.
* research personnel will ask the patients some questions about their health.
* If it has not already been done for usual medical care, patients will be asked to give a urine sample to test for medical conditions that may result in a higher risk of having kidney problems such as having glucose (sugar) in the urine.
If the patient is eligible to continue in the study, the following will also happen at the initial day of enrollment:
* research personnel may draw about 4 tablespoons of blood from the vein or, if from the IV that was (or will be) placed for usual medical care.
* If one of the 100 patients who are at low risk of kidney problems, they will have a CT scan of the chest that was ordered by the doctor.
* Otherwise, the potential subject will be randomly assigned to have either a CT scan of the chest, which will include dye given in an IV, or a VQ scan, that does not use IV dye. One half will have the CT scan and one half will have the VQ scan.
* Potential subjects will also have an ultrasound (a painless sound wave test of the legs to look for a clot in the legs that can cause a clot in the lungs), if the doctor thinks that one is needed, or if the VQ scan is "indeterminate." Indeterminate means that the radiologist, the doctor reading the VQ scan, cannot tell if there is a pulmonary embolism (a clot in your lung). Research personnel expect that less than 5% (5 out of 100) patients will have a VQ scan that is indeterminate. Some patients who have a VQ scan that is indeterminate, may also need to have a CT scan of their chest to be sure that they do or do not have a clot in their lungs.
* research personnel will also save blood and urine samples. Later, these samples will be used to test for electrolytes (salts) and proteins (that may help better predict who will get kidney problems. Subjects will not have to pay for these tests because they will not be used for usual medical care. To protect privacy, research personnel will use a code instead of name to label samples. For this reason, research personnel will not be able to tell the results of these tests.
* If you are not found to be eligible for this study, the reason will be discussed with you and your treating provider. If you are eligible to continue in the study, the following will happen later:
* Subjects will be given an appointment to return to the hospital between 2 and 7 days from the initial visit. As a reminder, research personnel will give subjects a reminder card; research personnel will call and/or text the subjects, and/or email with reminders. If subjects are still in the hospital during this time, research personnel will visit the subjects in the hospital.
* At this appointment research personnel will ask some questions about the health, will take about 4 tablespoons of blood and a urine sample. Blood and urine will be used to test for kidney problems. If these tests do show a kidney problems after having IV dye, research personnel will send a letter to notify subjects and the treating physician.
* In 30 days, research personnel will make 3 attempts to call and ask some questions about the subject's health. If research personnel cannot follow up by telephone, they will also try to contact by text, and/or by mail.
* research personnel will also review medical records in 7 days, 30 days, and in 1 year.
