Age-related propofol effects on electrophysiological properties of isolated hearts
Journal
Anesthesia and Analgesia
Journal Volume
84
Journal Issue
5
Pages
964-971
Date Issued
1997
Author(s)
Abstract
We compared the direct effects of propofol on the conduction system of neonatal (3 mo) rabbit hearts using intracardiac recording/stimulation in Langendorff-perfusion and autonomic blockade. At a low concentration (3 micro M), propofol caused a slight but significant lengthening of the atrioventricular (AV) conduction interval of the adult hearts, but not of neonatal hearts. At a higher concentration (10 micro M and above), propofol significantly prolonged the AV conduction interval in a frequency-dependent manner in both neonates and adults. The AV Wenckebach cycle length was also lengthened, with the change more significant in the adults. However, with concentrations of propofol up to 100 micro M, the neonatal hearts frequently (9 of 13 experiments) progressed to complete AV block, which was not observed in the adults. Conduction through the atrial tissue (SA interval) and the His-Purkinje system (HV interval), as well as the spontaneous heart rate, were all slowed by propofol at 30 micro M or above. However, the lengthening of SA interval was more pronounced in the neonates, and only in the neonate was the atrial refractory period prolonged by propofol at 10 micro M and above. We conclude that 3 micro M propofol produces no significant direct effects on the neonatal cardiac electrophysiological properties, although AV conduction of the adult heart may be suppressed at this concentration of propofol. At higher concentrations, age-related propofol effects were demonstrated in the AV node and the atrial tissue. (Anesth Analg 1997;84:964-71)
SDGs
Publisher
Lippincott Williams and Wilkins
Type
journal article