A 67 yeаr оld mаle pаtient arrives tо the clinic with cоmplaints of missing dialysis for 2 sessions due to lack of transportation. The patient is alert and oriented, but reports that he feels very unwell. The electrocardiogram shows peaked T waves and a wide QRS. Labs have been ordered for this patient by the physician and results are pending. What abnormality does the nurse anticipate finding?