Four hours after the onset of pain from an MI, the nurse would expect an increase in which laboratory result?
A) Alkaline phosphatase (ALP)
B) CK-MB
C) Lactate dehydrogenase (LDH)
D) Leukocyte count

Question

Quizplus · Accepted Answer

Serum levels of CK-MB, an isoenzyme of creatine kinase (CK) found primarily in cardiac muscle, increase 3 to 6 hours after the onset of chest pain, peak in 12 to 18 hours, and return to normal levels in 2 to 3 days. CK-MB is one of the preferred cardiac enzymes for diagnosing myocardial infarction. The leukocyte count is measured as it does increase after MI, but is not diagnostic and does not have a predictable pattern of rise, peak, and return to normal. The other two options are not measured as part of the normal diagnostic workup for MI.

Four Hours After the Onset of Pain from an MI