Epinephrine application via an endotracheal airway and via the Combitube in esophageal position.

Abstract

To compare plasma concentrations and cardiovascular effects of epinephrine after application via a conventional endotracheal airway and via the esophageal lumen of a new emergency airway, the esophageal tracheal Combitube. Prospective, randomized study. Center for Biomedical Research, University of Vienna. Fourteen juvenile swine received either an endotracheal tube (Group A) or a Combitube in esophageal position (Group B). In Part I of the study, epinephrine was administered during spontaneous beating of the heart; in Part II, epinephrine was administered during cardiopulmonary resuscitation, using a ten-fold higher dosage in Group B, respectively. Plasma epinephrine levels were measured 1, 2, 3, 5, 7, 10, 15, and 30 mins after application. Systolic arterial blood pressure and cardiac output in Part I, and end-tidal CO2 and coronary perfusion pressure in Part II were recorded. In Part I, increased levels of plasma epinephrine and systolic arterial pressure were maintained significantly longer in Group B when compared with Group A. In Part II, no significant differences between the groups were found with regard to plasma epinephrine levels and hemodynamic variables. Epinephrine applied via the esophageal lumen of the Combitube in a ten-fold higher dosage has similar effects on plasma epinephrine levels and hemodynamic variables compared to endotracheal administration.