A client is admitted to the ED after complaining of acute chest pain radiating down the left arm. The client is diaphoretic and anxious, and has difficulty breathing. Which laboratory studies would the nurse anticipate?

Number 4 is correct.

Myoglobin, a small hemeprotein, becomes abnormal within 1 – 2 hours of myocardial infarction (MI). BUN and white blood cell levels do not provide relevant information when an MI is suspected. LDH, lactate dehydrogenase, will begin to rise 2 – 5 days after an MI.