The effect of atropine on the T-wave amplitude of ECG during isoflurane anaesthesia

• Published in: International journal of clinical monitoring and computing Vol. 11; no. 1; pp. 43 - 47
• Main Authors: ANNILA, P. A, YLI-HANKALA, A. M, LINDGREN, L
• Format: Journal Article
• Language: English
• Published: Dordrecht Kluwer 01-02-1994
• Subjects: Adolescent; Adult; Anesthesia, Inhalation; Anesthetics. Neuromuscular blocking agents; Atropine - pharmacology; Biological and medical sciences; Electrocardiography - drug effects; Electroencephalography - drug effects; Female; Heart Conduction System - drug effects; Heart Rate - drug effects; Humans; Isoflurane - pharmacology; Male; Medical sciences; Middle Aged; Monitoring, Intraoperative; Neuropharmacology; Parasympathetic Nervous System - drug effects; Pharmacology. Drug treatments; Signal Processing, Computer-Assisted; Sympathetic Nervous System - drug effects; Amplitude; Human; Anesthesia; Electroencephalography; T wave; Monitoring
• ISSN: 0167-9945
• DOI: 10.1007/BF01132843

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.