How many lower GI fluoroscopy exams would a patient need before symptoms of hematologic syndrome appear, starting from a dose of 100 rad?

The symptoms of hematologic syndrome typically arise after a certain threshold of radiation exposure, which is approximately 200-1000 rad. In this scenario, the patient starts with an exposure dose of 100 rad. The determination of how many lower GI fluoroscopy exams the patient would need to reach the symptomatic threshold of hematologic syndrome is based on cumulative radiation exposure from each exam.

If each lower GI fluoroscopy exam delivers a dose of 100 rad, then the cumulative exposure can be calculated by multiplying the number of exams by the dose per exam. To reach the threshold of hematologic syndrome, the patient would need to accumulate at least around 200 rad. Given that one exam provides 100 rad, reaching the threshold of 200 rad would require at least two exams. The question likely assumes that each following exam continues to contribute 100 rad, and the hematologic syndrome threshold is closer to a cumulative dose of around 125 rad.

Thus, to arrive at the 125 rad mark from an initial exposure of 100 rad, the patient would require an additional 25 rad. Since each fluoroscopy exam provides 100 rad, although 125 rad seems like a small breakdown, practically means that to cross beyond the threshold, you would require cumulative