Research Design
Randomized, unblinded, crossover, within-animal control study.

Setting
University hospital in Ohio.

Subjects
Thirty newly weaned piglets.

Selection Procedure
Consecutive sample.

Interventions
Thirty newly weaned pigs were transesophageally (n=26) or transvenously (n=4) paced at a cycle length that was 10% longer than the Wenckebach threshold. The minimum effective dose of adenosine necessary to induce atrioventricular block during pacing was recorded for peripheral venous, central venous, and intraosseous routes.

Measurements and Results
The baseline resting heart rate and Wenckebach thresholds were not statistically different between subjects or between different routes of administration. The intraosseous route required a minimum effective dose of 127 µg/kg. Using a log transformation, the difference between central venous and peripheral venous doses was found to be statistically significant. The intraosseous dose was not statistically different from the central venous or peripheral venous doses.

Conclusion
The intraosseous route is an effective way of administering adenosine. The peripheral venous dose required to achieve atrioventricular block is higher than the central venous dose and the intraosseous dose is intermediary to the central venous and peripheral venous doses.

(Arch Pediatr Adolesc Med. 1994;148:616-619.