Matsushima M, Kimura S, Kitaura A, Hamasaki S, Iwamoto T, Mino T, Masui K, Nakao S. Propofol suppresses the His-ventricular conduction in paediatric patients.
J Clin Pharm Ther 2020;
46:433-439. [PMID:
33098128 PMCID:
PMC7983984 DOI:
10.1111/jcpt.13302]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 10/01/2020] [Accepted: 10/06/2020] [Indexed: 12/03/2022]
Abstract
What is known and objective
Propofol is the most commonly used intravenous anaesthetic worldwide and is considered to be safe for all ages. However, there have been some reports that propofol induces severe atrioventricular (AV) blocks in humans and some studies demonstrated that propofol suppressed the cardiac conduction system in animals. A precise mechanism by which the block is induced has not been elucidated yet in humans. The objective of this study was to investigate the effects of propofol on the cardiac conduction system and the cardiac autonomic nervous balance in children.
Methods
We enrolled 23 paediatric patients (age: 6‐15 years; males: 16, females: 7) who were scheduled to undergo radiofrequency catheter ablation (RFCA) under general anaesthesia. Anaesthesia was induced with 2 mg/kg propofol and 0.5 µg/kg/min remifentanil, and tracheal intubation was performed with the aid of 1 mg/kg rocuronium. Anaesthesia was maintained with 5‐7 mg/kg/h propofol and 0.2 µg/kg/min remifentanil during the RFCA. After the completion of the RFCA, anaesthesia was further maintained with 5 mg/kg/h propofol and 0.2 µg/kg/min remifentanil for at least 10 min (LC: low propofol concentration state), followed by the injection of 2 mg/kg propofol and the infusion of 10 mg/kg/h propofol for 10 min (HC: high propofol concentration state). The sinus node recovery time (SNRT), sinoatrial conduction time (SACT), atrial‐His (AH) interval and the His‐ventricular (HV) interval were measured at the end of both the LC and HC. Cardiac autonomic regulation was simultaneously assessed based on heart rate variability.
Results and discussion
Propofol significantly suppressed intrinsic cardiac HV conduction, but did not affect the SNRT, SACT or the AH interval. As HV blocks, which occur below the His bundle, are often life‐threatening, the HV conduction delay may be a cause of severe AV blocks induced by propofol. Propofol directly suppressed parasympathetic nerve activity, and sympathetic nerve activity was also suppressed.
What is new and conclusion
These results indicate that propofol suppresses the HV conduction and might help to elucidate the mechanism by which propofol causes lethal AV blocks.
Collapse