R. Ishii et al., ATRIOVENTRICULAR-CONDUCTION DURING ADENOSINE-INDUCED HYPOTENSION IN DOGS ANESTHETIZED WITH SEVOFLURANE, British Journal of Anaesthesia, 77(3), 1996, pp. 393-398
We have studied the effects of adenosine-induced hypotension on A-H in
terval (atrioventricular (AV) nodal conduction time during sinus rhyth
m), St-H interval (intra-atrial plus AV nodal conduction time during a
trial pacing), H-V interval (His-Purkinje conduction time) and H-S int
erval (total ventricular conduction time) by Hisbundle electrocardiogr
aphy in addition to surface electrocardiogram during both sinus rhythm
and atrial pacing in nine dogs anaesthetized with 1 MAC of sevofluran
e. Stepwise increases in infusion rates of adenosine to 0.1, 0.3, 0.5
and 1.0 mg kg(-1) min(-1) produced a dose-related decrease in mean art
erial pressure from 91 (6) to 38 (2) mm Hg. Adenosine significantly in
creased the A-H interval at infusion rates of 0.5 mg kg(-1) min(-)1 an
d above, and the St-H interval at 1.0 mg kg(-1) min(-1). The H-V and H
-S intervals remained unchanged. Heart rate decreased significantly on
ly at 1.0 mg kg(-1) min(-1) with a significant increase in the PR inte
rval. Adenosine-induced hypotension did not have deleterious effects o
n AV conduction times and the surface electrocardiogram in dogs anaest
hetized with 1 MAC of sevoflurane. This may indicate that the effects
of adenosine on AV conduction were small and therefore are unlikely to
be a contraindication to the use of adenosine for inducing hypotensio
n in patients with initially normal conduction during sevoflurane anae
sthesia.