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Swine are frequently used in medical research given their similar cardiac physiology to that of humans. Measuring cardiac parameters such as stroke volume and cardiac output are essential in this type of research. Contrast ventriculography, thermodilution, and pressure-volume loop (PV-loop) catheters can be used to accurately obtain cardiac performance data depending on which resources and expertise are available. For this study,five Yorkshire swine were anesthetized and intubated. Central venous and arterial access was obtained to place the necessary measurement instruments.A temperature probe was placed in the aortic root. A cold saline bolus was delivered to the right atrium and temperature deflection curve was recorded. Integration of the area under the curve allowed for the calculation of the current cardiac output.A pigtail catheter was percutaneously placed in the left ventricle and 30 mL of iodinated contrast was power injected over 2 seconds. Digital subtraction angiography images were uploaded to volumetric analysis software to calculate the stroke volume and cardiac output. A pressure volume-loop catheter was placed into the left ventricle (LV) and provided continuous pressure and volume data of the LV, which allowed the calculation of both stroke volume and cardiac output.All three methods demonstrated good correlation with each other. The PV-loop catheter and thermodilution exhibited the best correlation with a 3% error and a Pearson coefficient of 0.99, with 95% CI=0.97 to 1.1, (p=0.002). The PV-loop catheter against ventriculography also showed good correlation with a 6% error and a Pearson coefficient of 0.95, 95% CI=0.96 to 1.1 (p=0.01). Finally, thermodilution against ventriculography had a 2% error with r=0.95, 95% CI=0.93 to 1.11, (p=0.01). In conclusion, we state that the PV-loop catheter, contrast ventriculography, and thermodilution each offer certain advantages depending on the researcher's requirements. Each method is reliable and accurate for measuring various cardiac parameters in swine such as the stroke volume and cardiac output.

Hemorrhage constitutes the majority of potentially preventable deaths from trauma. There is growing interest in endovascular resuscitation techniques such as selective aortic arch perfusion (SAAP) for patients in cardiac arrest. This involves active perfusion of the coronary circulation via a thoracic aortic balloon catheter and is approaching clinical application. However, the technique is complex and requires refinement in animal models before human use can be considered. This paper describes a large animal model of exsanguination cardiac arrest treated with a bespoke SAAP system. Swine were anesthetized, instrumented and a splenectomy was performed before a controlled, logarithmic exsanguination was initiated. Animals were heparinized and the shed blood collected in a reservoir. Once cardiac arrest was observed, the blood was pumped through an extra-corporeal circuit into an oxygenator and then delivered through a 10 Fr balloon catheter placed in the thoracic aorta. This resulted in the return of a spontaneous circulation (ROSC) as demonstrated by ECG and aortic root pressure waveform. This model and accompanying SAAP system allow for standardized and reproducible recovery from exsanguination cardiac arrest.