American Board of Internal Medicine (ABIM) Certification Practice Exam

Patients with a NIHSS greater than what value are automatically excluded from receiving tPA?

1. 20

2. 25

3. 30

4. 15

The correct answer is: 25

The correct answer is based on established guidelines for the administration of intravenous tissue plasminogen activator (tPA) in the context of acute ischemic stroke. The National Institutes of Health Stroke Scale (NIHSS) quantifies the severity of stroke symptoms. A higher NIHSS score indicates a more severe clinical presentation of a stroke. According to these guidelines, patients with an NIHSS greater than 25 are typically excluded from receiving tPA. This is due to the increased risk of complications and a lower likelihood of favorable outcomes in patients with such high scores, which often indicate a greater degree of neurological impairment. The exclusion threshold is in place to minimize the risk of hemorrhagic transformation and other adverse events that can occur when administering thrombolysis in severely affected individuals. Patients with NIHSS values of 20 or less may still be candidates for tPA treatment, depending on additional clinical factors and assessments. Therefore, recognizing the cutoff at an NIHSS score greater than 25 aids healthcare providers in making informed decisions regarding the use of tPA in potentially beneficial scenarios while safeguarding against complications in high-risk patients.