Baseline patient and operative characteristics.

<p>Baseline patient and operative characteristics.</p

Number of red blood cell units transfused on the day of surgery to each patient according to development of postoperative atrial fibrillation.

<p>Dashed line represents the average number of transfused units for each patient.</p

Distribution of maximum and mean storage time of red blood cell units transfused according to development of postoperative atrial fibrillation.

<p>Dashed lines represent the average storage time.</p

Risk for development of postoperative atrial fibrillation according to storage time of transfused red blood cell units.

<p>The baseline risk (dotted line) represents the risk when receiving 1–3 units of RBC, being male gender, being <60 years of age, receiving no medication (β-blocker, ACE-inhibitor, calcium antagonist), not having COPD or peripheral arteriosclerosis and when having a combined surgery as the surgery type.</p