I heard that ketamine is a street drug or an animal tranquilizer? Why are you using this drug?

Safety. Ketamine (Ketalar, ParkeDavis) was introduced in 1964 as a complete intravenous anesthetic agent for humans. We have since learned that ketamine is better suited as an addition (adjuvant) to rather than a 'stand alone' anesthetic in humans above the age of ten. The safety profile of ketamine is the reason it is also used in veterinary anesthesia.

There have been no deaths reported from clinical doses of ketamine which is not the case for the opioids (i.e. morphine, Demerol, fentanyl). One cannot equate the clinically controlled use of ketamine from the media reports of deaths from uncontrolled doses of questionable purity.

Ketamine had fallen into disfavor among anesthesiologists for the same reason it is being abused on the street; i.e. its hallucinogenic potential. Many websites exist to describe ketamine for street use. This is not one. Titrating the propofol to a BIS® range between 70-75 prevents hallucinations from ketamine, making the agent predictable. This accounts for the growing resurgence in the clinical use of ketamine by anesthesiologists who insist on predictablility, as well as safety, from the agents they employ.