Peculiarities of general anaesthesia in the investigation of heart electrophysiology

Investigating electrophysiological properties of the heart under acute experimental conditions, dogs are affected by operative stress because of traumatic surgical manipulations, so investigations are performed under general anaesthesia. Many anaesthetics together with their main function have desintegrating influence on autonomic regulation mechanisms. That is why anaesthetics used during experiments must fullfill such requirement \u96 have minimal influence on autonomic nervous system (ANS) and heart conductivity system (HCS) interaction parameters or to make this influence insignificant. We did not found common anaesthesy methodics that can fullfill that requirements, so we decided to prepare new common anaesthesia methodics, which could fullfill requirements mentioned above. We choose medicaments according to their pharmacokinetics and pharmacodynamics action. For methodics optimization we\u92ve used 2 groups of dogs ( mongrel dogs males weight 7\u9615 kg) (n=10). We\u92ve applied different anaesthesia schemas on each group. Premedication in the I-st group was performed with intramuscle (IM) combination of diazepam, ketamine and phentanyl and for anaesthesia continuous intravenous (IV) infusion of thiopental and ketamine. In II-nd group premedication was performed with IM injection of ketamine/ phentanyl combination and for anaesthesia \u96 continuous IV infusion of thiopental. Induction in both groups was performed with IV thiopental injection. Suitability of premedication and anaesthesia was valued by adequativity of haemodynamics (heart rate 1/min) and surgical manipulations during experiments. Our conclusion is: investigating interaction of ANS and HCS methodics used in the I-st group of dogs is more suitable