Brazilian Perfusionists And Arterial Roller Pump Adjustment: Comparison Between Static And Dynamic Calibration Method [os Perfusionistas Brasileiros E O Ajuste Do Rolete Arterial: Comparação Entre A Calibração Estática E Dinâmica]

Introduction: Roller pumps play an important role in extracorporeal circulation. However, occlusion of the rollers should be adequately performed and this can be adjusted mainly by two methods: static and dynamic. Objective: To investigate how the Brazilian perfusionists adjust arterial roller pumps in their services and evaluate the application of a Device to Assist Calibration (DAC) that facilitates roller adjustment by the dynamic calibration method. Methods: We installed a roller pump with accessories to perform adjustment by drop rate (static calibration) and dynamic calibration methods during the XXVIII Brazilian Congress of Extracorporeal Circulation. Perfusionists were asked to adjust the roller pump according to the procedure they usually do in their service. After each adjustment pressure was measured by dynamic calibration method with DAC. The research was approved by the Research Ethics Committee of UNICAMP, N° 1144/2010. Results: There were 56 perfusionists in this study. Pressure average of 56 measurements of dynamic calibration was 434 ± 214 mmHg; 76% of measurements were within the recommended range for the use of the dynamic calibration method (between 150 and 500 mmHg). Conclusion: Brazilians perfusionists tend to adjust roller pumps with less occlusive settings. The amplitudes of the dynamic calibration pressure tend to be smaller for more experienced perfusionists because their skills increase with time. The device can be used by the perfusionists to adjust roller pumps with greater accuracy and mainly repeatability in few minutes.262205212Murray, C.J.L., Lopez, A.D., The Global Burden of Disease: A Comprehensive Assessment of Mortality and Disability from Disease, Injuries and Risk Factors in 1990 and Projected to 2020, , Boston:Harvard School of Public HealthGomes, W.J., Mendonça, J.T., Braile, D.M., Resultados em cirurgia cardiovascular. 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(2009) Rev Bras Cir Cardiovasc, 24 (3), pp. 373-381Benfatti, R.A., Carli, A.F., Silva, G.V.R., Dias, A.E.M.A.S., Goldiano, J.A., Pontes, J.C.D.V., Influência do ácido épsilon aminocapróico no sangramento e na hemotransfusão pósoperatória em cirurgia valvar mitral (2010) Rev Bras Cir Cardiovasc, 25 (4), pp. 510-515Sá, M.P.B.O., Lima, L.P., Rueda, F.G., Escobar, R.R., Cavalcanti, P.E.F., Thé, E.C.S., Estudo comparativo entre cirurgia de revascularização miocárdica com e sem circulação extracorpórea em mulheres (2010) Rev Bras Cir Cardiovasc, 25 (2), pp. 238-244Silva, A.M.R.P., Campagnucci, V.P., Pereira, W.L., Rosa, R.F., Franken, R.A., Gandra, S.M.A., Revascularização do miocárdio sem circulação extracorpórea em idosos: Análise da morbidade e mortalidade (2008) Rev Bras Cir Cardiovasc, 23 (1), pp. 40-45Leverett, L.B., Hellums, J.D., Alfrey, C.P., Lynch, E.C., Red blood cell damage by shear stress (1972) Biophys J, 12 (3), pp. 257-273Bernstein, E.F., Gleason, L.R., Factors influencing hemolysis with roller pumps (1967) Surgery, 61 (3), pp. 432-442Hansbro, S.D., Sharpe, D.A., Catchpole, R., Welsh, K.R., Munsch, C.M., McGoldrick, J.P., Haemolysis during cardiopulmonary bypass: An in vivo comparison on standard roller pumps, nonocclusive roller pumps and centrifugal pumps (1999) Perfusion, 14 (1), pp. 3-10Linneweber, J., Chow, T.W., Kawamura, M., Moake, J.L., Nosè, Y., In vitro comparison of blood pump induced platelet microaggregates between a centrifugal and roller pump during cardiopulmonary bypass (2002) Int J Artif Organs, 25 (6), pp. 549-555Takahama, T., Kanai, F., Hiraishi, M., Onishi, K., Yamazaki, Z., Suma, K., Long-term nonheparinized left heart bypass (LHB): Centrifugal pump or roller pump (1985) Trans Am Soc Artif Intern Organs, 31, pp. 372-376Lawson, D.S., Ing, R., Cheifetz, I.M., Walczak, R., Craig, D., Schulman, S., Hemolytic characteristics of three commercially available centrifugal blood pumps (2005) Pediatr Crit Care Med, 6 (5), pp. 573-577Asant-Siaw, J., Tyrrell, J., Hoschtitzky, A., Dunning, J., Does the use of a centrifugal pump offer any additional benefit for patient having open heart surgery? 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Laser Doppler Anemometry Measurements Of Steady Flow Through Two Bi-leaflet Prosthetic Heart Valves [velocimetria Laser De Escoamento Permanente Através De Duas Próteses Cardíacas De Duplo Folheto]

Introduction: In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench. Objective: To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21-751 and 21 AJ-501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream. Methods: To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min.) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements. Results: It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found. Conclusions: Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21-751 (RegentTM) is superior to the 21 AJ-501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves.284462469Yoganathan, A.P., He, Z., Casey, J.S., Fluid mechanics of heart valves (2004) Ann Rev Biomed Eng, 6, pp. 331-362Dasi, L.P., Simon, H.A., Sucosky, P., Yoganathan, A.P., Fluid mechanics of artificial heart valves (2009) Clin Exp Pharmacol Physiol, 36 (2), pp. 225-237Chew, Y.T., Chew, T.C., Low, H.T., Lim, W.L., Techniques in the determination of the flow effectiveness of prosthetic heart valves. In: Cardiovascular techniques: Biomechanical systems: Techniques and applications. vol. II. London:Cornelius Leondes CRC Press LLC, 2001, pp. 70-117Yoganathan, A.P., Chandran, K.B., Sotiropoulus, F., Flow in prosthetic heart valves: State-of-the-art and future directions (2005) Ann Biomed Eng, 33 (12), pp. 1689-1694Grigioni, M., Daniele, C., D'Avenio, G., Morbiducci, U., Del Gaudio, C., Abbate, M., Innovative technologies for the assessment of cardiovascular medical devices: State-of-the-art techniques for artificial heart valve testing (2004) Expert Rev Med Devices, 1 (1), pp. 81-93Meyer, R.S., Deutsch, S., Bachmann, C.B., Tarbell, J.M., Laser Doppler velocimetry and flow visualization studies in the regurgitant leakage flow region of three mechanical mitral valves (2001) Artif Organs, 25 (4), pp. 292-299Pinotti, M., Is there correlation between the turbulent eddies size and mechanical hemolysis? (2000) J Braz Soc Mech Sci, 22. , http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-73862000000400006, Available from: URLMeyer, R.S., Deutsch, S., Maymir, J.C., Geselowitz, D.B., Tarbell, J.M., Three-component laser Doppler velocimetry measurements in the regurgitant flow region of a Björk-Shiley monostrut mitral valve (1997) Ann Biomed Eng, 25 (6), pp. 1081-1091Lu, P.C., Lai, H.C., Liu, J.S., A reevaluation and discussion on the threshold limit for hemolysis in a turbulent shear flow (2001) J Biomech, 34 (10), pp. 1361-1364Woo, Y.R., Yoganathan, A.P., Pulsatile flow velocity and shear stress measurements on the St. Jude bileaflet valve prosthesis (1986) Scand J Thorac Cardiovasc Surg, 20 (1), pp. 15-28(2005) Cardiovascular Implants-cardiac Valve Prostheses, , American National Standard, ISO 5840Cheade, E.L., (2008) Atualização De Sistema Duplicador De Pulsos Para Teste De Válvulas Cardíacas [Dissertação De Mestrado], p. 120. , Campinas: UNICAMP, Faculdade de Engenharia Elétrica e de ComputaçãoBazan, O., Ortiz, J.P., Design conception and experimental setup for in vitro evaluation of mitral prosthetic valves (2011) Rev Bras Cir Cardiovasc, 26 (2), pp. 197-204Bazan, O., Ortiz, J.P., Sistema Duplicador De Pulsos Para Análise In Vitro De Próteses De Válvulas Cardíacas-testes Preliminares De Validação, , www.metallum.com.br/7colaob/resumos/trabalhos_completos/02-015.docx, em: 7o Congresso Latino Americano de Órgãos Artificiais e Biomateriais, COLAOB 2012, 2012, Natal/ RN, Proceedings of COLAOB 2012, disponível emde Paulis, R., Schmitz, C., Scaffa, R., Nardi, P., Chiariello, L., Reul, H., In vitro evaluation of aortic valve prosthesis in a novel valved conduit with pseudosinuses of Valsalva (2005) J Thorac Cardiovasc Surg, 130 (4), pp. 1016-1021Dasi, L.P., Ge, L., Simon, H.A., Sotiropoulo, S.F., Yoganathan, A.P., Vorticity dynamics of a bileaflet mechanical heart valve in an axisymmetric aorta (2007) Phys Fluids, 19 (6), pp. 067105-067117Medical, S.J., (2010) Cardiac Surgery, , U.S. Product Catalog, AprilBlais, C., Pibarot, P., Dumesnil, J.G., Garcia, D., Chen, D., Durand, L.-G., Comparison of valve resistance with effective orifice area regarding flow dependence (2001) Am J Cardiol, 88 (1), pp. 45-52Dotta, F., Torres, M., Manfroi, W., Guaragna, J.C.V.C., Caramoni, P., Albuquerque, L.C., Desproporção prótese aórtica-paciente: Definição, impacto e prevenção (2007) Rev Bras Ecocardiogr, 20 (4), pp. 34-38Zhang, M., Wu, Q.C., Intra-supra annular aortic valve and complete supra annular aortic valve: A literature review and hemodynamic comparison (2010) Scand J Surg, 99 (1), pp. 28-31Seitelberger, R., Bialy, J., Gottardi, R., Seebacher, G., Moidl, R., Mittelöck, M., Relation between size of prosthesis and valve gradient: Comparison of two aortic bioprosthesis (2004) Eur J Cardiothorac Surg, 25 (3), pp. 358-363Guenzinger, R., Eichinger, W.B., Hettich, I., Bleiziffer, S., Ruzicka, D., Bauernschimitt, R., A prospective randomized comparison of the Medtronic Advantage Supra and St Jude Medical Regent mechanical heart valves in the aortic position: Is there an additional benefit of supra-annular valve positioning? (2008) J Thorac Cardiovasc Surg, 136 (2), pp. 462-47