A comparison of the effects of fentanyl and propofol on left ventricular contractility during myocardial stunning.
BACKGROUND
The intravenous anaesthetic propofol has been shown to possess free radical scavenging activity and calcium channel blocking effects in a number of in vitro models. We decided to compare the effects of propofol with those of fentanyl on myocardial contractility during and after ischaemia to determine whether propofol could protect the heart and improve recovery of ventricular contractile function in open-chested dogs.


METHODS
Twenty adult beagles were acutely instrumented, under halothane anaesthesia, to measure ECG; aortic, left ventricular pressures; cardiac output; coronary flow; and segmental lengths in the regions perfused by the left anterior and left circumflex coronary arteries. After surgery and a stabilisation period halothane anaesthesia was terminated and fentanyl (100 microg x kg[-1] bolus followed by 2 microg x kg[-1] x min[-1] infusion; n=10) or propofol (5 mg x kg[-1] bolus followed by 0.3 mg x kg[-1] x min[-1] infusion; n=10) anaesthesia commenced. After a stabilisation period the LAD coronary artery was occluded for 10 min and then reperfused for 3 h. Measurements were taken throughout the protocol.


RESULTS
We found no significant difference in recovery of contractile function between propofol and fentanyl as assessed by normalised preload recruitable work area (50+/-10 vs 47+/-16%), normalised systolic shortening (36+/-12 vs 48+/-14%) and peak left ventricular dP/dt (1665+/-276 vs 1846+/-151 mmHg x s[-1]) at the end of reperfusion.


CONCLUSIONS
We conclude that at the concentration used in this study propofol shows no improvement in contractility during "stunning" when compared to fentanyl.
Ross
S
S
The Nuffield Department of Anaesthetics, The Radcliffe Infirmary, University of Oxford, England, United Kingdom.
Muñoz
H
H
Piriou
V
V
Ryder
W A
WA
Foëx
P
P
D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001011:Aorta / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000494:pharmacology; D002302:Cardiac Output / Q000187:drug effects; D002316:Cardiotonic Agents / Q000008:administration & dosage / Q000494:pharmacology; D003326:Coronary Circulation / Q000187:drug effects; D003331:Coronary Vessels / Q000187:drug effects; D003971:Diastole; D004285:Dogs; D004562:Electrocardiography / Q000187:drug effects; D005283:Fentanyl / Q000008:administration & dosage / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000008:administration & dosage / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D009200:Myocardial Contraction / Q000187:drug effects*; D017202:Myocardial Ischemia / Q000503:physiopathology; D015425:Myocardial Reperfusion; D017682:Myocardial Stunning / Q000503:physiopathology*; D010101:Oxygen Consumption / Q000187:drug effects; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D013599:Systole; D016277:Ventricular Function, Left / Q000187:drug effects*; D017725:Ventricular Pressure / Q000187:drug effects
D018686:Anesthetics, Intravenous; D002121:Calcium Channel Blockers; D002316:Cardiotonic Agents; D016166:Free Radical Scavengers; D005283:Fentanyl; D015742:Propofol