Objective Content Validation of the Hemodynamic and Technical Parameters of the OrpheusTM Cardiopulmonary Bypass Simulator.

The utilization of simulators for training is increasing in the professions associated with cardiac surgery. Before applying these simulators to high-stakes assessment, the simulator's output data must be validated. The aim of this study is to validate a Cardiopulmonary Bypass (CPB) simulator by comparing the simulated hemodynamic and technical outputs to published clinical norms. Three Orpheus™ CPB simulators were studied and compared to a published reference of physiologic and technical metrics that are managed during clinical CPB procedures. The limits of the simulators user modifiable variables were interrogated across their full range and the results were plotted against the published clinical norms. The data generated with the simulator conforms to validated clinical parameters for patients between 50 and 110 kg. For the pre- and post-CPB periods, the independent variables of central venous pressure (CVP), heart rate (HR), contractility, and systemic vascular resistance (SVR) must be operated between the limits of 7 and 12 mmHg, 65 and 110 beats/min, 28% and 65%, and 6 and 32 units respectively. During full CPB the arterial pump flows should be maintained between 3.5 and 5.5 LPM and SVR between 18 and 38 units. Validated technical parameters during cardioplegia delivery are expected at solution flow rates between 250 and 400 mL/min and 100 and 225 mL/min for antegrade and retrograde delivery routes, respectively. We have identified the limits for user-modifiable settings that produce data conforming to the physiologic and technical parameter limits reported in the peer reviewed literature. These results can inform the development of simulation scenarios used for high stakes assessments of personnel, equipment, and technical protocols.

Preserving ECMO Cannulae Patency.

Extracorporeal membrane oxygenation (ECMO) is often managed using minimal anticoagulation. This can make the circuitry susceptible to thrombosis. The ECMO cannula may be particularly vulnerable to thrombosis if flow is interrupted for an undetermined but prolonged period of time. Therefore, under conditions where cannula blood flow stasis may be prolonged and flashing, the cannulae is not an option (e.g., air in circuit) it is imperative to have an emergency plan available, which can be rapidly implemented that will provide a means of cannula patency preservation. The following outlines a system to preserve cannula patency in these instances.