Application of low-volume zero-balanced ultrafiltration and its effect on blood propofol concentration: a randomized controlled trial.

AIM

The aim of this study was to evaluate the effectiveness of low-volume zero-balanced ultrafiltration during cardiopulmonary bypass in heart valve replacement surgery.

METHODS

This was a randomized, double-blind, controlled study carried out in the operating room. Forty patients of ASA grade II-III, elected to undergo heart valve replacement surgery, were enrolled. All patients were randomly assigned to either a low-volume (35 mL/kg) zero-balanced ultrafiltration group (N.=20) or to a control group (N.=20). Blood propofol concentrations and entropy index were measured using cardiopulmonary bypass. Concentrations of plasma tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interleukin-10 (IL-10), and cardiac troponin I were measured before and after the end of cardiopulmonary bypass and corrected according to hematocrit.

RESULTS

Blood levels of cardiac troponin I, TNF-alpha, IL-6, and IL-10 after surgery were all significantly lower in the ultrafiltration group than in the control group (P<0.05) after the end of bypass. Blood propofol concentrations decreased significantly in both groups during cardiopulmonary bypass and remained significantly lower in the ultrafiltration group than the control group. However, there was no significant difference between the two groups in the entropy index (P=0.5583).

CONCLUSION

Low-volume zero-balanced ultrafiltration performed during cardiopulmonary bypass surgery significantly decreased post-bypass levels of the cytokines, TNF-alpha, IL-6, IL-10, and postoperative cardiac troponin I. Blood propofol concentration was also decreased; however, the depth of anesthesia was not affected significantly.