A comparison of endotracheal and intravenous routes for atropine administration in anaesthetised dogs

The endotracheal route for atropine administration was compared with the intravenous route in 50 anaesthetised dogs. The response to drug administration was recorded as the change in heart rate from a steady pretreatment value. An indication was found of a positive relationship between the dose and the response to atropine given endotracheally. The increase in heart rate following atropine administration was similar, in terms of magnitude and speed of onset, when given by the endotracheal route at 0–06 mg/kg, as compared with that obtained by the intravenous administration of atropine at 0–04 mg/kg (P<0–05).