You are working on a high-acuity medical surgical unit and just came on shift. You are prioritizing care for four patients who were just admitted. Which patient should you assess first?

The patient with an allergy to penicillin who is receiving an infusion of vancomycin (Vancocin)

The patient with a pulse of 58 beats/min who is about to receive digoxin (Lanoxin)

The NPO patient with a blood glucose level of 80 mg/dL who just received 20 units of 70/30 Novolin insulin

The patient with a blood pressure of 136/92 mm Hg who complains of having a headache