Effects Of Agonal Respiration On Coronary Perfusion Pressure During Untreated Cardiac Arrest

Objective:To describe ventilatory dynamics and coronary perfusion pressure (CPP) following the onset of ventricular fibrillation (VF) without treatment in an experimental swine model.Methods:Ten female mixed-breed domestic swine (25.0±1.5kg) were anaesthetis-ed, intubated and mechanically ventilated. VF was induced, and untreated for8minu-tes. Respiratory rate, incidence, aortic pressure and right atrial pressure were record-ed until respiratory activity ceased. CPP were calculated.Results:All animals presented with agonal respiration from1to6minutes after VF Agonal respiration followed a crescendo—decrescendo pattern. The first and last agonal respirations were respectively observed at2.09±0.82minutes and5.21±1.12minutes. Agonal respiration significantly increased in frequency over the4to5minutes of untreated cardiac arrest. Following the expiratory phase, increases in CPP were observed (p<0.05).Conclusion:This study demonstrates that during untreated VF, the expiratory phases of gasping are associated with increases in CPP. All the animals presented with gasping at the4to5min interval of untreated cardiac arrest. Agonal respiration significantly increased in frequency over the4to5minutes of untreated cardiac arrest and followed a crescendo—decrescendo pattern.