Every surgery or dentistry for pets needs anesthesia.To do anesthesia some medications like Hydromorphone, Acepromazine, Ketamine and Diazepam are used and to maintain anesthesia, anesthetic gas like Isoflurane is necessary.Every medication has to be metabolized by liver and kidneys to ged rid of them.Therefore normal  function of liver and kidneys are vital to sent them out via urination and defecation.

On the other hand anesthesia causes low blood pressure and this phenomenon can make problem for pets with kidney disease.

In addition every surgical approach needs incision and this causes bleeding.Needless to say having normal coagulation pattern is vital to prevent from bleeding during surgery.

By doing pre-surgical blood test your vet can judge that surgery for  your pet is safe or not.If not,how to change it to safe surgery like treatment of kidney or liver disease or using special medications which are safe for your pets.