Effects of general anaesthesia in dorsal recumbency with and without vatinoxan on bronchoalveolar lavage cytology of healthy horses.

The research article investigates the effects of general anaesthesia in horses when they are in a dorsal recumbency (lying on their back) position, with and without the use of vatinoxan. The study examines whether anaesthesia induces lung inflammation by looking at changes in bronchoalveolar lavage fluid (BALF), and also explores if vatinoxan can influence these results.

Objective of the Study

• The main focus of the study was to understand when maximum lung inflammation occurs and how quickly BALF cytology returns to its normal state after the horse is anesthetized in a dorsal recumbency position.
• The secondary objective was to evaluate the potential effects of vatinoxan, a new medication, on the results of BALF cytology.

Methodology

• Six healthy horses were studied in this observational crossover research.
• The horses underwent multiple BALF and blood sample collections for one week after general anesthesia with two different treatment protocols, and without anesthesia (control).
• For both treatments, the horses were premedicated with medetomidine-vatinoxan or medetomidine-placebo. Anaesthesia was induced with ketamine-midazolam and maintained with isoflurane for one hour while the horses were in a dorsal recumbency position.
• The differences in BALF and blood variables between the anesthesia protocols and control were analysed using repeated measures analysis of variance models.

Findings of the Study

• Anaesthesia in dorsal recumbency didn’t result in notable changes in airway cytology. This means that any changes observed could not be differentiated from the effect of repeated BALF sampling.
• No differences in BALF matrix metalloproteinase gelatinolytic activity were detected between the two treatments or the control series. Matrix metalloproteinases are enzymes that degrade extracellular matrix proteins, playing a crucial role in cell behaviors such as migration, differentiation, proliferation, and death.
• An irregular increase in a protein called serum amyloid A was observed in some animals. This protein usually indicates inflammation.
• Vatinoxan as a premedicant did not consistently alter lung cytology or blood inflammatory markers after anesthesia, suggesting it may not have a significant effect in this context.