How to reduce embolism during CPB? : the surgical tips

1. How to reduce embolism during CPB? : the surgical tips 상계백병원 흉부외과 허재학

2. Neurologic complications ; stroke after cardiac surgery • 3.1 % stroke in 2108 patients in a prospective study --- Roach GW 1996 • Stroke 2.8% in 2000 patients studied prospectively, with an incidence in patients > 75 years (8.9%), 65 -74 years (3.6%) and < 60 years old(0.9 %) --- Tuman KJ 1999

3. Cognitive deficits after cardiac surgery • 79% significant decrease in cognitive performance postoperatively --- Shaw PJ 1986 • 53 % at discharge, 36 % at 6 wks, 24 % at 6 mo --- Newman MF 1996 • 90 % cognitive impairment in pump CABG, no impairment in OPCAB --- Diegeler A 2000 • Reduced retinal and cerebral microembolization with OPCAB --- Ascione R 2005

4. Major source of emboli during CPB Hammon JW. 2008, Cohn LH ed. Cardiac Surgery in the Adult

5. Atherosclerosis of the ascending aorta • The main risk factor for postoperative stroke --- van der Linden 2001, Hogue 1999, Roach 1996, Blauth 1995 • < 2 % strokein patients with limited or no atheroma • 40 % in patients with grade IV or V atheroma --- advanced therapy in cardiac surgery, Barbut 1997 • The incidence of atherosclerosis in CABG patients ; 38 ~ 53 % ---Barbut 1996, Bolotin 2005

6. Evaluation of atherosclerosis • Preop CT / MRI • Digital palpation • Epiaortic ultrasonography • TEE

7. Categorization of Aortic Atherosclerosis • group I clean aorta • group II remote, stable aortic plaque • group III remote, vulnerable plaque/ulcer • group IV lesions near cannulation site • group V dangerous/impossible cannulation or clamping 박계현, 2009 관상동맥외과 연구회 학술 심포지움

8. Aortic atherosclerosis vs. mortality n=77 n= 100 n=45 n=26 n=36

9. Preop CT for detecting aortic atheroma preop. CT vs EAU preop. CT vs TEE Berman P. Heart Surg Forum 7, 2004:E245-E249 - sensitivity 87 %, specificity 82 % Tenenbaum A. Radiology, Vol 208, 153-158

10. Epiaortic Ultrasonography The SonoSite ultrasound device displayed alone and with monitor stand

12. TEE showing aortic plaque Kronzon I. et al. Circulation 2006;114:63-75

13. A Comparison of DP, TEE and EAU Suvarna et al. J Cardiothorac and Vasc Anes. 2007: 805-809

14. Changes in surgical planning Bolotin G et al. Chest 2005;127:60-65 • reduction in neurologic complications (Ozatik MA 1999, Royse AG 2000)

15. Comparison of Various Surgical Techniques to the Development of a Postoperative Stroke Kapetanakis EI et al. Ann Thorac Surg 2004;78:1564-1571

16. Scatterplot shows value of aortic atheroma in predicting number of emboli Barbut, D. et al. Stroke 1996;27:87-90

17. TEE showing ehcogenic signals within aorta Barbut D. et al.; Ann Thorac Surg 1997;63:1262-1267

18. Distribution of embolic signals (ES) across specific operative events • aortic cross clamp release accounted for 42% (TEE) and 41% (TCD) of the total number of emboli Barbut, D. et al. Stroke 1996;27:87-90

19. Rate of microemboli detection during each surgical intervention Taylor R. L. et al.; Ann Thorac Surg 1999;68:89-93

20. EMBOL-X Intraaortic Filtration System (Mountain View, Edwards)

21. Emboli caught in the Embol-X filter Banbury M. K. et al.; Ann Thorac Surg 2003;76:508-515

22. Distal Aortic Arch Cannulation Borger M. A. et al.; J Thorac Cardiovasc Surg 1999;118:740-745 • Cannulation using a long cannula ; significant decrease in peak forward flow velocity and turbulence in the aortic arch during CPB Grossi EA. Et al. Ann Thorac Surg 1995;59:710-712

23. the Cardeon Cobra catheter Cook D. J. et al.; J Thorac Cardiovasc Surg 2003;125:378-384

24. Schematic of the Aegis catheter Cook D. J. et al.; Ann Thorac Surg 2002;74:825-829

25. Prevention of air microembolism • usual de-airing maneuvers - incomplete to eliminate retained air • CO2 flooding to replace the air in the thoracic cavity

26. CO2 insufflation into the cardiothoracic wound • CO2 dissolves in blood and tissue >25 times faster than air • 50 % heavier than air • --- but, residual air in pericardial cavity 20 – 80 %, delivered in common manner (Martens S 2001, Persson M 2003)

27. Efficiency of de-airing; CO2 delivery(1) Svenarud, P 2004

29. Efficiency of de-airing; CO2 delivery(2) Svenarud, P 2004

30. Effect of CO2 Insufflation in Open-Heart Surgery median number of microemboli after release of aortic cross-clamp p < 0.01 Svenarud, P. et al. Circulation 2004;109:1127-1132

31. Effect of CO2 Insufflation total numbers of microemboli present in different areas shown by TEE p < 0.01 Svenarud, P. et al. Circulation 2004;109:1127-1132

32. Scanning electron micrographs of 40-micron arterial line filters Hogue, CW et al. Anesth Analg 2006;103:21-37

33. The progression of gaseous microemboli through a CPB circuit Jones T. J. et al.; Ann Thorac Surg 2002;74:2132-2137

34. Residual air in the venous cannula increases cerebral embolization r = 0.524, p < 0.0001 Rodriguez R. A. et al.; Eur J Cardiothorac Surg 2006;29:175-180

35. Reduction of Gaseous Microembolism Using a Dynamic Bubble Trap Schoenburg M.; J Thorac Cardiovasc Surg 2003;126:1455-60

36. Small capillary and arteriolar dilatations (SCADs) after cardiac surgery canine brain tissue with cardiotomy suction (Brooker RF 1998) Brain with fat emboli(Moody DM 1995)

37. Processing scavenged blood with a cell saver reduces cerebral lipid microembolization Closed bars represent arterial filter group; open bars represent cell saver group 11 ± 3 vs 24 ± 5, p= 0.02 Kincaid E. H. et al.; Ann Thorac Surg 2000;70:1296-1300

38. Proportion of total microemboli during each event Taylor R. L. et al.; Ann Thorac Surg 1999;68:89-93

39. Summary • Avoid the atherosclerotic emboli ; preop. CT, EAU • Control the air entry site and remove residual air from the heart strictly • Insufflate the CO2 gas to replace the air ; inside wound cavity, gas diffuser • Eliminate the air in the venous cannula • Wash the blood aspirated from the surgical wound ; the continuous auto transfusion cell saver system • Specialized cannula or filtration device • Cannulate in distal arch using a long cannula