The effect of atropine on the T-wave amplitude of ECG during isoflurane anaesthesia.
The effect of bolus dose of atropine (20 micrograms kg-1) on the R/T-wave amplitude ratio of electrocardiogram was studied in 12 patients during isoflurane anaesthesia at electroencephalogram burst suppression level (mean ET of isoflurane 1.8 vol-%). The amplitude ratio was measured before, 1, 2, 5 and 10 min after atropine. Change was measured as decibels and 95% confidence intervals were calculated. The amplitude of T-wave flattened significantly after atropine. It is concluded, that the ECG T-wave amplitude reflects the balance of sympathetic and parasympathetic nervous activity during isoflurane anaesthesia. The use of the decibel transformation and confidence intervals seems to be a relevant method to interpret changes in physiologic measures during anaesthesia.
Annila
P A
PA
Department of Clinical Medicine, University of Tampere, Finland.
Yli-Hankala
A M
AM
Lindgren
L
L
D000293:Adolescent; D000328:Adult; D000769:Anesthesia, Inhalation; D001285:Atropine / Q000494:pharmacology*; D004562:Electrocardiography / Q000187:drug effects*; D004569:Electroencephalography / Q000187:drug effects; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007530:Isoflurane / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010275:Parasympathetic Nervous System / Q000187:drug effects; D012815:Signal Processing, Computer-Assisted; D013564:Sympathetic Nervous System / Q000187:drug effects
D001285:Atropine; D007530:Isoflurane