Abstract 36: Gasping Augments Carotid Blood Flow During Cardiac Arrest
Introduction. Coincident with an “agonal” gasp during cardiac arrest, there are prominent increases in stroke volumes even in the absence of chest compression. In the present study, we tested the hypothesis that gasps also increase carotid blood flow during cardiac arrest.
Methods. In 10 domestic male pigs weighing 40 ± 3 kg, ventricular fibrillation (VF) was electrically induced and untreated for 5 minutes. The right femoral artery and vein were cannulated. Intrathoracic pressure (ITP) was measured with the aid of a balloon tipped catheter advanced into the esophagus for a distance of 35 cm. A transonic flowprobe (Ultrasonic Blood Flow Meter, T101, Transonic Systems Inc, Ithaca, NY) was placed around the right common carotid artery for measurement of carotid blood flow (CBF).
Results. Gasps increased in frequency during the first 4 minutes of untreated VF together with increases in CBF (Figure⇓). Significant increases in CBF were highly correlated with the decreases in ITP during the inspiration phase of the gasps (r = 0.77).
Conclusion. Spontaneous gasps produce significant increases in carotid blood flow during untreated cardiac arrest. Preliminary studies confirm concurrent increases in microvascular cerebral blood flow.