Which of the following steps is/are appropriate for a 65-year-old woman who develops atrial fibrillation with associated mild hypotension and rapid ventricular response following partial gastric resection?

A. Correction of electrolytes and blood chemistries.

B. Evaluation for possible myocardial infarction. 

D. Attempt to limit the ventricular response with digitalis.

DISCUSSION: When a patient develops postoperative atrial fibrillation following an extracardiac procedure, correction of the patient's blood chemistries and electrolytes is essential. The patient must also undergo evaluation for a possible myocardial infarction as the cause of the atrial dysrhythmia. The first rule in treatment is to slow the ventricular response and attempt to limit hemodynamic instability. Digitalis is effective in slowing down the ventricular response and thus improving the hemodynamic status of the patient. Lidocaine has little use in controlling atrial dysrhythmias but is very effective in decreasing ventricular ectopy. Immediate cardioversion is rarely indicated for new-onset atrial fibrillation. Only after correction of all underlying metabolic and electrolyte defects as well as an attempt at medical conversion and ventricular rate control is cardioversion recommended.