Effects of different techniques of endotracheal epinephrine administration in pediatric porcine hypoxic-hypercarbic cardiopulmonary arrest.
OBJECTIVE
To compare three endotracheal epinephrine instillation techniques in a pediatric porcine hypoxic-hypercarbic cardiopulmonary arrest model.


METHODS
Prospective, randomized, laboratory comparison of three instillation techniques.


METHODS
Large animal research facility at a children's hospital.


METHODS
Thirty-six preadolescent anesthetized and paralyzed Yucatan swine (mean weight 10.0 +/- 1.9 kg) with apnea-induced hypoxic and hypercarbic cardiopulmonary arrest.


METHODS
After 8 mins of cardiopulmonary arrest and 1 min of cardiopulmonary resuscitation (CPR), 500 micrograms (51 +/- 9 micrograms/kg) of radiolabeled endotracheal epinephrine was administered by direct injection (n = 17), injection via feeding catheter (n = 10), or via monitoring lumen built into the sidewall of the endotracheal tube (n = 9). CPR was resumed and continued for 5 mins. If resuscitation occurred, monitoring was continued for 1 hr. Outcome variables included successful resuscitation, pulmonary distribution, heart rate, mean arterial pressure, plasma radiolabeled epinephrine counts, and total plasma epinephrine concentrations. Analysis by Fisher's exact test, one-way analysis of variance and Pearson's phi coefficient was performed.


RESULTS
Successful resuscitation occurred in 31% of all pigs with no difference between groups (p = .69). Bilateral distribution occurred in 39% with no difference between groups (p = .25). No correlation was noted between successful resuscitation and distribution (p = .65). HR, mean arterial pressure, plasma radiolabeled epinephrine counts, and total plasma epinephrine concentrations showed significant changes over time within groups, but no difference between groups at any time point. Adherence of the epinephrine dose to the endotracheal tube was < or = 1.5% in all cases.


CONCLUSIONS
Instillation of 50 micrograms/kg of endotracheal epinephrine by three different techniques during pediatric porcine asphyxial arrest does not affect resuscitation rate, pulmonary distribution, hemodynamic response, or plasma exogenous and total epinephrine concentrations. No correlation was found between successful resuscitation and bilateral distribution. Therefore, currently recommended cumbersome endotracheal epinephrine instillation techniques may offer no resuscitation advantage over commonly used direct injection in this setting.
Jasani
M S
MS
Department of Anesthesia, A.I. duPont Institute, Wilmington, DE 19899.
Nadkarni
V M
VM
Finkelstein
M S
MS
Mandell
G A
GA
Salzman
S K
SK
Norman
M E
ME
D000818:Animals; D001049:Apnea / Q000150:complications; D004353:Drug Evaluation, Preclinical; D004837:Epinephrine / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D006323:Heart Arrest / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D006935:Hypercapnia / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D000860:Hypoxia / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D007322:Instillation, Drug; D008722:Methods; D011897:Random Allocation; D012151:Resuscitation; D013552:Swine; D013997:Time Factors; D014132:Trachea
D004837:Epinephrine