The effects of modified ultrafiltration on pulmonary function and transfusion requirements in patients underwent coronary artery bypass graft surgery

Objective: The inflammatory response after cardiac surgery increases vascular permeability leading to higher mortality and morbidity in the post operative time. The modified ultrafiltration (MUF) had shown benefits on respiratory, and hemodynamic in pediatric patients. This approach in adults is not well established yet. We hypothesize that modified ultrafiltration may improve respiratory, hemodynamic and coagulation function in adults after cardiac surgeries. Methods: A prospective randomized study was carried out with 37 patients who underwent coronary artery bypass graft surgery (CABG) were randomized either to MUF (n=20) at the end of bypass or to control (no MUF) (n=17). The anesthesia and ICU team were blinded for the group selection. The MUF were carried out for 15 minutes after the end of bypass. The patients data were taken at beginning of anesthesia, ending of bypass, ending MUF, 24 hours, and 48 hours after surgery. For clinical outcome the pulmonary, hemodynamic and coagulation function were evaluated. Results: We observed lower drain loss in the MUF group compared to control group after 48 hours (598 +/- 123 ml vs. 848 +/- 455 ml; P=0.04) and required less red blood cells units transfusion compared to control group (0.6 +/- 0.6 units/patient vs.1.6 +/- 1.1 units/patient; P=0.03). The MUF group showed lower airway resistance (9.3 +/- 0.4 cmH(2)O center dot L-1s-1 vs. 12.1 +/- 0.8 cmH(2)O center dot L-1s-1; P=0.04). There were no deaths in both groups. Conclusion: The MUF reduces post operatory bleeding and red blood cells units transfusion, but with no differences on clinical outcome were observed. The routinely MUF employment was not associated with hemodynamic instability.