Does zero balance ultrafiltration decrease the incidence of post-cardiopulmonary bypass atrial fibrillation?

Atrial fibrillation is the most frequent cardiac dysrhythmia after cardiac surgery. Postoperative atrial fibrillation (Afib) is shown to increase risk of stroke, congestive heart failure, and hemodynamic instability leading to increased hospital length of stay and cost. Inflammation and degenerative histologic changes in cell structure because of age may predispose patients to a higher susceptibility. Cardiac surgery with cardiopulmonary bypass (CPB) induces a systemic inflammatory response syndrome (SIRS) responsible for a number of postoperative complications including arrhythmias. Zero balance ultrafiltration (ZBUF) has been shown to decrease SIRS by removing some of its mediators and products from the blood. The purpose of this retrospective analysis is to determine whether ZBUF does decrease the incidence of Afib after CPB. Retrospective review was conducted on consecutive primary coronary artery bypass patients placed on CPB from the period of January 2004 to June 2006. Data were collected from perfusion records, patient charts, blood bank records, and a cardiac surgery clinical database consisting of patient demographics, occurrence of postoperative Afib, ZBUF, blood product administration, antifibrinolytic use, bypass and aortic cross-clamp times, comorbidities, personnel, postoperative time on ventilator, and postoperative length of stay. Univariate analysis was performed on all numerical and categorical data for possible inclusion into a regression model for a p value of .05. New onset postoperative Afib was found in 48 patients (27%). One hundred twenty-seven patients (73%) did not develop postoperative Afib. The variables age and gender remained with odds ratio point estimates indicating that for every unit increase in age, the odds of Afib increased by a factor of 1.078. The odds of Afib increase by 2.629 for female gender. Statistical analysis did not prove the hypothesis, but did show that older age and female gender play a role in the occurrence of postoperative Afib.