○ If criteria suggest a possibility of PE, a blood test should be ordered. The blood test, called a d-dimer test, helps determine if a blood clot might be present. Clinicians should take a patient's age into consideration when reviewing blood test (d-dimer) results. If the blood test does not show that a blood clot might be present, no additional testing is needed. If the blood test shows an increased risk for blood clots, imaging tests, such as a CT scan, should be ordered.