Abstract:

Objective To investigate the effect of prolonged high-dose propofol infusion with mechanical ventilation on myocardial injury in rabbits. Methods Eighteen healthy New Zealand white rabbits were randomized into propofol group (group P, n=6), isoflurane group (group S, n=6) and isoflurane+10% Intralipid group (group SI, n=6) after tracheal intubation. Propofol was infused in group P, and the infusion velocity was adjusted to the desired sedation level. Isoflurane was inhaled in group S and group SI, and the inhalation concentration was also adjusted to the desired sedation level. The velocity of Intralipid infusion in group SI was the same as that of propofol infusion in group P. The experiment lasted for 36 h or till the animal death. Femoral venous blood samples were taken before propofol infusion and 0, 12, 24 and 36 h during experiment for examinations of biochemical parameters. Myocardial tissues were obtained after experiment for immunohistochemical staining, and the expression of tumor necrosis factor-α（TNF-α）was detected. Results All rabbits in group P were dead, while rabbits in the other two groups survived for at least 36 h. The maximum velocity of propofol infusion in group P was 65 mg·kg^-1·h^-1. Blood pressure in group P was significantly lower than that in group S and group SI (P<0.05). The levels of triglyceride, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and creatine kinase at the time points of 12 h, 24 h and 36 h were significantly higher than those at he time point of 0 h in group P (P<0.05). And there were significant differences in levels of creatine kinase between group P and group S or group SI at corresponding time points (P<0.05). The expression of TNF-α in myocardial tissues in group P was significantly higher than that in group S and group SI. Conclusion Prolonged high-dose propofol infusion may cause myocardial injury in rabbits.

Key words: propofol, mechanical ventilation, infusion syndrome, rabbit