Horizon Information Portal

MSOE Library Home

MSOE Library Home

Home

An investigation into the dampening of pulsatile energy in a cardiopulmonary bypass circuit / by Erik F. Prossen.

by Prossen, Erik F.

Blood -- Circulation, Artificial

Extracorporeal Circulation -- methods

Blood -- Viscosity

75 leaves : ill. ; 29 cm.

Thesis advisor: Dr. Ronald Gerrits.

Committee members: Dr. Larry Fennigkoh, Shannon Voborsky.

Introduction -- Background -- Materials and methods -- Results -- Discussion -- Conclusion -- A: Calculated EEP data -- B: MINITAB R15 oxygenator test results -- C: MINITAB R15 arterial filter ANOVA results -- D: MINITAB R15 circuit EEP ANOVA results.

Pulsatile flow may not be an entirely new development in the arena of cardiopulmonary bypass; however, pump technology has developed to the point that pulsatile flow during cardiopulmonary bypass is safe, cost-effective, and relatively efficient. A plethora of research has been conducted into the potential positive and negative effects of employing pulsatile flow during cardiopulmonary bypass. One area in which considerable research exists in the pediatric cardiopulmonary bypass arena involves the dampening of Energy Equivalent Pressure (EEP) in the bypass circuit. Little research has been conducted into the dampening of EEP in adult-sized bypass circuits.

This paper examines the dampening of EEP in an adult-sized bypass circuit. Specifically, a comparison between the dampening of EEP through two commercially pulsatile pump settings on EP production. An experiment was developed to test the dampening of EEP by measuring flow and pressure at the pump outlet, oxygenator outlet, and arterial filter outlet. Two circuits were built for this experiment: one circuit used the Terumo RX25 resrvoir with a separate Medtronic Affinity Arterial Line Filter. The other circuit used a Terumo FX25 oxygenator with integrated arterial filter. Independent variables included two levels of oxygenators or circuits (RX25 and ALF, FX25), three flow rates (3.4 L/min, 4.3L/min, and 4.9L/min) and four different pulsatile pump settings (base percentages varying between 100%-30%, and width percentages varying between 100%-60%). Flow was measured with a Transonic ME-PXL clamp-on flow sensor and data recorded with Windaq software. Pressure was measured with a BioBench analog-digital converter and BioBench software. The degree of EEP dampening across each circuit element, overall circuit dampening of EEP, and EEP production as a result of pulse settings were compared for analysis.

The results of this experiment show that the FX25 circuit dampened half as much EEP as the RX25 and arterial line filter circuit. Additionally, the amount of EEP going to the "patient" in the FX25 circuit was statistically significantly higher than in the RX25 circuit. The results of the pulse setting analysis show that EEP production increases significantly as base percentages and width percentages decrease from 100%. Additionally, a base setting of 30% and width setting of 60% significantly increased EEP production over all other pulse settings. It can therefore be concluded that to maximize EEP production in a cardiopulmonary bypass circuit, a perfusionist should employ a FX25 oxygenator using pulse pump settings of 30% base and 60% width.

Horizon Information Portal 3.25_9885

Powered by SirsiDynix

© 2001-2013 SirsiDynix All rights reserved.

Horizon Information Portal