This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

1. To determine if adults undergoing noncardiac thoracic surgery who receive a prophylactic intervention have a lower incidence of postoperative atrial fibrillation (AF) than patients who do not receive a prophylactic intervention.

2. To determine if there are adverse events associated with the use of these prophylactic interventions. Specifically we will determine if there are differences in the incidence of strokes, ventricular arrhythmias and hypotension.

For the purpose of this review, prophylactic interventions are new interventions administered to patients undergoing noncardiac thoracic surgery for the purpose of reducing the incidence of AF in those patients who are initially in sinus rhythm. The interventions are grouped into the following classes of intervention: A) cardiovascular agents, B) elemental supplementation, C) anti‐inflammatory agents. These interventions are to be administered either in the preoperative period, during the operation, or immediately at the end of the operation. We will not consider maintaining anti‐arrhythmic medication in patients who are already receiving the medication as a prophylactic intervention.