Does ketamine/propofol anesthesia possess antiarrhythmogenic quality? A perioperative study in aortocoronary bypass...

We compared ketamine/propofol (KP) anesthesia with the commonly used high dose fentanyl (F) anesthesia in patients who underwent aortocoronary bypass surgery. The doses of anesthetic drugs and their time schedule of administering was standardized. The study period included the postoperative ICU stay. 31 patients were enrolled (15 in the KP- and 16 in the F-group). The measured and calculated hemodynamic data were intra- and postoperative not statistically different,except the mean and systolic arterial pressure (p = 0.049), which were in the KP-group from the first postoperative hour higher. After separation from bypass the F-patients were more dependent of adrenoreceptor agonists for hemodynamic stabilization than the KP-patients. The postoperative Holter ECG monitoring resulted in following issues: ventricular tachycardias, ventricular salvos and ventricular couplets were significantly less to observe in the KP-group. A difference existed also in the frequency of ventricular extrasystoles, but without statistical significance. No patient fulfilled all criteria for a perioperative myocardial infarction, although in some patients one or two pathologic enzyme value or a pathologic change in the postoperative ECG could be proved. Ketamine resembles in the chemical structure cocaine, therefore it shares with cocaine some effects: inhibiting the neuronal uptake of catecholamines and acting as a sodium-channel blocker. Inhibiting the sodium current is one of the kinds how antiarrhythmic drugs work.

The study indicates that the use of ketamine for anesthesia and perioperative sedation coincidences with fewer ventricular rhythm disturbances than with opioid and benzodiazepine as anesthetic and sedation agents.