A standard comparison of esophageal obturator airway and endotracheal tube ventilation in cardiac arrest

A comparison of esophageal obturator airway^® (EOA^®) and endotracheal tube (ET) ventilation was performed while standardizing the method of oxygen delivery and assuring true sampling of arterial blood. Forty-eight victims of prehospital cardiac arrest had an arterial blood gas drawn in the emergency department while being ventilated with an EOA. Endotracheal intubation was performed immediately thereafter and another blood gas was drawn. All patients without a pulse were sampled through an arterial line placed by cutdown. Patients who developed a pulse during the resuscitation were sampled percutaneously or by arterial line. Patients with a perfusing rhythm (N = 19) had the following mean EOA blood gas values: pH, 7.34 ± .17; PCO₂, 28 ± 8 mm Hg; and PO₂, 420 ± 125 mm Hg. Their subsequent mean ET blood gas values were pH, 7.40 ± .13; PCO₂, 25 ± 8 mm Hg; and PO₂, 390 ± 100 mm Hg. Pulseless patients (N=29) had mean EOA blood gas values of pH, 7.36 ± .26; PCO₂, 32 ± 21 mm Hg; and PO₂, 285 ± 192 mm Hg. Their subsequent mean ET blood gas values were pH, 7.30 ± .21; PCO₂, 36 ± 26mm Hg; and PO₂ 260 ± 185 mm Hg. There was no statistically significant difference in the PCO₂ or PO₂ obtained with EOA compared with ET ventilation. There was a significant difference in the pH corrected for respiratory acidosis in pulseless patients, but not in patients with a perfusing rhythm. We conclude that the EOA, when used with an oxygen-powered breathing device, is an effective means of airway management, with the ventilation achieved equal to that of an endotracheal tube.