[Application of dynamic bubble trap in coronary artery bypass with cardiopulmonary bypass: an initial study].
OBJECTIVE
To investigate the effectiveness of dynamic bubble trap (DBT) on air microbubble elimination from both the cardiopulmonary bypass (CPB) circuit and middle cerebral arteries, and evaluate its possible impact on blood cells and coagulatory function.


METHODS
Twenty patients undergoing coronary artery bypass graft (CABG), 12 males and 8 females, with similar perioperative data were assigned randomly to DBT group and control group. Each CABG was finished with identical circuit sets except the integration of a DBT between the arterial filtrator and the aortic cannula in the DBT group. Air microbubbles were detected before and after the integration of DBT with ultrasonographic detector and microembolism signals (MES) in middle cerebral arteries were counted by transcranial Doppler (TCD). Plasma free hemoglobin (PFH), lactate dehydrogenase (LDH), fibrinogen, platelet count, coagulation factor II and anti-thrombin III (ATIII) were also assayed respectively before the operation, at the termination of CPB, and 6 hours after the operation.


RESULTS
In the DBT group the microbubbles of different size could be expelled significantly with the clearance rates between 68% - 74% (10 - 120 microm bubbles), 79% - 81% (20 - 120 microm bubbles), and 88% - 96% (40 - 120 microm bubbles). During the total CPB phase, the mean number of MES reached 197 +/- 137 in the control group and 158 +/- 178 in the DBT group, without a significant difference between these 2 groups. The PFH and LDH levels raised while the platelet count, fibrinogen level, and coagulation factor II and AT III activities decreased sharply after CPB in these 2 groups, however without significant differences in these parameters between the two groups.


CONCLUSIONS
DBT integration into the CPB circuit enhances neither blood cell damage nor coagulation disturbance. DBT effectively eliminates air microbubbles in arterial conduit; however, its microembolus elimination function is prone to die down during the total period of CPB.
Wu
Ming
M
Department of Cardiothoracic Surgery, Second Affiliated Hospital of School of Medicine, Zhejiang University, Hangzhou 310009, China.
Chen
Ru-kun
RK
Cremer
Johan
J
D002315:Cardiopulmonary Bypass / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D001026:Coronary Artery Bypass / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery*; D004618:Embolism, Air / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D005374:Filtration / Q000295:instrumentation; D006801:Humans; D020766:Intracranial Embolism / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D007431:Intraoperative Complications / Q000517:prevention & control; D008297:Male; D045423:Microbubbles; D017585:Ultrasonography, Doppler, Transcranial