Atrial and His-Purkinje conduction times during isoflurane anaesthesia in humans.
The effect of isoflurane 2.0 MAC on human atrioventricular conduction time was studied. A non-invasive recording system for the detection of His-Purkinje potentials based on signal averaging techniques was used. Recordings were made in 15 patients before and after induction with isoflurane. We were able to measure atrial (P-H) and His-Purkinje (HPS) conduction times in 11 patients. Mean (+/- SEM) P-H conduction time decreased from 101.8 +/- 5.3 to 89.3 +/- 3.3 ms (P less than 0.01). HPS conduction times did not change significantly. Heart rate increased significantly from 86.7 +/- 4.2 to 94.9 +/- 4.7 beats min-1 (P less than 0.05). Systolic blood pressure decreased from 117.3 +/- 4.6 to 94.1 +/- 4.7 mmHg (P less than 0.05). It is concluded that the effects of isoflurane on supraventricular conduction time in humans depend on interactions of several different mechanisms.
Scheffer
G J
GJ
Department of Anaesthesiology, Free University Hospital Amsterdam, The Netherlands.
Van Schagen
N T
NT
Jonges
R
R
Ros
H H
HH
Peper
A
A
De Lange
J J
JJ
D000293:Adolescent; D000328:Adult; D000703:Analog-Digital Conversion; D000769:Anesthesia, Inhalation; D001283:Atrioventricular Node / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002036:Bundle of His / Q000187:drug effects*; D002648:Child; D004562:Electrocardiography / Q000187:drug effects / Q000379:methods; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007530:Isoflurane / Q000494:pharmacology*; D008875:Middle Aged; D009431:Neural Conduction / Q000187:drug effects*; D011690:Purkinje Fibers / Q000187:drug effects*; D013997:Time Factors
D007530:Isoflurane