The protective effects of ketamine and propofol in obstructive jaundice: an experimental study

Oxidative stress under general intravenous and inhalation anaesthesia

Oxidative stress occurs when reactive oxygen species (ROS) production overwhelms cell protection by antioxidants. This review is focused on general anaesthesia-induced oxidative stress because it increases the rate of complications and delays recovery after surgery. It is important to know what effects of anaesthetics to expect in terms of oxidative stress, particularly in surgical procedures with high ROS production, because their either additive or antagonistic effect may be pivotal for the outcome of surgery. In vitro and animal studies on this topic are numerous but show large variability. There are not many human studies and what we know has been learned from different surgical procedures measuring different endpoints in blood samples taken mostly before and after surgery. In these studies most intravenous anaesthetics have antioxidative properties, while volatile anaesthetics temporarily increase oxidative stress in longer surgical procedures.

L-carnitine reduces acute lung injury in experimental biliary obstruction

OBJECTIVES

To investigate the protective effects of L-carnitine (LC) on lungs in an experimental obstructive jaundice (OJ) model.

METHODS

This was conducted for 2 months between May 2011 and July 2011 at Suleyman Demirel University School of Medicine Experimental and Clinical Research Center, Isparta, Turkey. Thirty-eight Wistar-Albino rats with an average weight of 250-300 g were divided into 3 groups of control, OJ, and OJ + L-carnitine treatment (LCT). L-carnitine was injected intravenously into the tail vein at a dose of 50 mg/kg/day for 10 days to the LCT group. Animals were sacrificed 10 days later. Enzyme levels were measured in the lung tissue; malondialdehyde, myeloperoxidase (MPO), glutathione peroxidase (GSH-Px), catalase, and superoxide dismutase. Tumor necrosis factor-alfa, interleukin 6 (IL-6), IL-8, and C-reactive protein levels were studied in plasma samples. Histopathological changes in the lungs were examined. 

RESULTS

There was a decreased in GSH-Px, MPO, and IL-8 levels (p less than 0.05) in the LCT group. The histopathological examination showed that neutrophil leukocyte infiltration and edema formation decreased and destruction of lung parenchyma disappeared following the treatment with LC (p less than 0.05). 

CONCLUSION

L-carnitine has a protective effect against lung damage due to experimental obstructive jaundice, possibly by altering anticytokine and antioxidant activity, and by decreasing the neutrophil migration.

Protective effects of intravenous anesthetics on kidney tissue in obstructive jaundice

AIM: To evaluate the protective effects on kidney tissue of frequently used intravenous anesthetics (ketamine, propofol, thiopental, and fentanyl) in rats with obstructive jaundice.

METHODS: There is an increased incidence of postoperative acute renal failure in patients with obstructive jaundice. Thirty-two Wistar-albino rats were randomly divided into four equal groups. Laparatomy was performed on each animal in the four groups and common bile ducts were ligated and severed on day 0. After 7 d, laparotomy was again performed using ketamine, propofol, thiopental, or fentanyl anesthesia whose antioxidative properties are well known in oxidative stress in a rat liver model of obstructive jaundice. After 2 h, the rats were sacrificed. Renal tissue specimens were analyzed for catalase, superoxide dismutase and malondialdehyde enzymes activities. All values are expressed as the mean ± SD. P values less than 0.05 were considered statistically significant.

RESULTS: All animals survived without complications until the end of the study. Enlargement in the bile duct and obstructive jaundice were observed in all rats. Catalase was found to be significantly lower in the fentanyl group than in the ketamine (P = 0.039), propofol (P = 0.012), and thiopental (P = 0.001) groups. Superoxide dismutase activities were similar in all groups (P > 0.05). Malondialdehyde was found to be significantly lower in the ketamine group than in the propofol (P = 0.028), thiopental (P = 0.002) and fentanyl (P = 0.005) groups. Malondialdehyde was also lower in the fentanyl group than in the thiopental group (P = 0.001). The results showed that obstructive jaundice sensitizes renal tissue to damage under the different anesthetics.

CONCLUSION: Among the agents tested, ketamine and propofol generated the least amount of oxidative stres on renal tissues in this rat model of obstructive jaundice created by common bile duct ligation. The importance of free radical injury in renal tissue in obstructive jaundice under different intravenous anesthetics during hepatobiliary and liver transplant surgery should be considered for prevention of postoperative acute renal failure.