Use of a dynamic bubble trap in the arterial line reduces microbubbles during cardiopulmonary bypass and microembolic signals in the middle cerebral artery

Abstract

Neurological complications remain an important cause of morbidity and mortality of patients following cardiopulmonary bypass (CPB). Microemboli, as well as cerebral hypoperfusion, are the main postulated mechanisms. This study demonstrates that the insertion of a dynamic bubble trap (DBT) into the curcuit reduces microbubbles in the arterial line and microembolic signals (MES) in the middle cerebral arteries (MCAs).

We investigated 12 patients during coronary artery bypass grafting (CABG). The DBT was inserted between the arterial filter and the arterial cannula. For detection of microemboli before and after the DBT, a special ultrasound Doppler device was used. MES were detected by transcranial Doppler monitoring in both MCAs of the patients. Microbubbles and MES were counted during bypass. These data were compared to 12 patients who were operated in a previous period without the use of a DBT. There were no significant differences in both groups with respect to gender, age, crossclamp and bypass time and number of anastomoses. In the group without a DBT in the circuit, a mean of 6311 microbubbles per operation could be observed distal to the arterial filter, corresponding to 282 MES. After inclusion of a DBT, we could register, in the second group, 8496 microemboli proximal and 2915 distal of the DBT, corresponding to 89 MES per operation. The reduction rate of microbubbles in the tubing was 65.7%, corresponding to a reduction in MES of about 86.2%. We conclude that the insertion of a DBT in the arterial line of CPB circuit protects the cerebrovascular system from microembolic events, as demonstrated by lower MES counts.

Get full access to this article

View all access options for this article.

References

Roach GW , Kanchuger M , Mangano CM et al. Adverse cerebral outcome after coronary bypass surgery . N Engl J Med 1996; 335: 1857-1863 .

Walzer T , Herrmann M , Wallesch CW. Neuropsychological disorders after coronary bypass surgery . J Neurol Neurosurg Psychiatry 1997; 6: 644-648 .

Clark RE , Brillman J , Davis DA , Lovell MR , Price TR , Magovern GJ. Microemboli during coronary artery bypass grafting . J Thorac Cardiovasc Surg 1995; 2: 249-258 .

Pugsley W , Klinger L , Paschalis C , Treasure T , Harrison M , Newman S. The impact of microemboli during cardiopulmonary bypass on neuropsychological functioning . Stroke 1994; 25: 1393-1399 .

Marcus H. Transcranial Doppler detection of circulating cerebral emboli: a review . Stroke 1993; 24: 1246-1250 .

Jenderka KV , Dietrich G , Cobet U , Kopsch B , Klemenz A , Urbanek P. Detection and estimation of microbubble size distribution in blood . Proceedings 16th Int. Congress on Acoustics 1998; 3: 1845-1846 (ISBN 1-56396= 817-7).

Urbanek S , Tiedtke HJ. Improved methods for measurement of gaseous microbubbles during extracorporeal circulation . Perfusion 2002; 6: 429-434 .

Borger MA , Peniston CM , Weisel RD , Vasiliou M , Green RE , Feindel CM. Neuropsychologic impairment after coronary bypass surgery: effect of gaseous micro-emboli during perfusionist interventions . J Thorac Cardiovasc Surg 2001; 4: 743-749 .

Borger MA , Feindel CM. Cerebral emboli during cardiopulmonary bypass: effect of perfusionist interventions and aortic cannulas . J Extracorp Technol 2002; 1: 29-33 .

10.

Schönburg M , Urbanek P , Erhardt G , Taborski U , Plechinger H , Klövekorn WP. Air microbubbles reduction during cardiopulmonary bypass: case study . J Extracorp Technol 2000; 3: 165-169 .

11.

Müllges W , Berg D , Babin-Ebell J , Toyka KV , Elert O. Cerebral microembolus generation in different extra-corporeal circulation systems . Cerebrovasc Dis 1999; 9: 265-269 .

12.

Urbanek P , Erhardt G , Taborski U , Schönburg M , Klövekorn WP. Dynamische Luftfalle-Methode zur Beseitigung von Luftmikrobläschen aus Tiedtke HJ, arteriellem Blut während extrakorporealen Zirkulation . Kardiotechnik 1999; 8: 100-102 .

13.

Schönburg M , Urbanek P , Erhardt G et al. Significant reduction of air microbubbles with the dynamic bubble trap during cardiopulmonary bypass . Perfusion 2001; 5: 19-25 .

14.

Selnes OA , Goldsborough MA , Borowicz LM , McKhann GM. Neurobehavioural sequelae of cardio-pulmonary bypass . Lancet 1999; 353: 1601-1606 .

15.

Mitchel S , Gorman D. The pathophysiology of cerebral arterial gas embolism . J Extracorp Technol 2002; 1: 18-23 .

16.

Kilo J , Czerny M , Gorlitzer M et al. Cardiopulmonary bypass affects cognitive brain function after coronary artery bypass grafting . Ann Thorac Surg 2001; 72: 1926-1932 .

17.

Braekken SK , Reinvang I , Russell D , Brucher R , Svennevig JL. Association between intraoperative cerebral microembolic signals and postoperative neuropsychological deficit: comparison between patients with cardiac valve replacement and patients with coronary artery bypass grafting . J Neurol Neurosurg Psychiatry 1998; 65: 573-576 .

18.

Deklunder G , Roussel M , Lecroart JL , Prat A , Gautier C. Microemboli in cerebral circulation and alteration of cognitive abilities in patients with mechanical prosthetic heart valves . Stroke 1998; 29: 1821-1826 .

19.

Perthel M , Kseibi S , Bendisch, A , Laas J. The dynamic bubble trap reduces microbubbles in extracorporeal circulation and high intensity transient signals in the middle cerebral artery: a case report . Perfusion 2003; 18: 325-329 .

20.

Taborski U , Urbanek P , Erhardt G et al. In vitro biocompatibility evaluation of the dynamic bubble trap . Artif Organs. 2003; 27: 736-743 .

21.

Ringelstein EB , Droste DW , Viken L et al. Consensus on microembolic detection by TCD . Stroke 1998; 29: 725-729 .

22.

Newman MF , Grocott HP , Mathew JP et al. Report of the substudy assessing the impact of neurocognitive function on quality of life 5 years after cardiac surgery . Stroke 2001; 32: 2874-2881 .

23.

Newman MF , Kirchner JL , Phillips-Bute B et al. Long-itudinal assessment of neurocognitive function after coronary artery bypass surgery . N Engl J Med 2001; 344: 395-402 .