Whether he is being neutered, having a broken bone fixed or undergoing an internal organ operation, your dog may have to go under the knife at some point. For operations like these, your dog will be administered an anesthetic agent to sedate him until the procedure is over. Different types of anesthesia exist, and depending on factors like his health and age, your dog may not be the ideal candidate for some of them.
Because anesthesia drugs that sedate your pet have a dramatic effect on his body, your vet needs to determine his risk for sedation before surgery. This typically involves a physical exam to check his heart, lungs, liver and kidneys, all of which are strongly affected by the anesthetic -- and will eventually flush them out of his system. Older dogs with weaker hearts or lungs may not be good candidates for all types of anesthesia, but certain drug formulas, particularly inhalants that allow for quick sedation and recovery, are generally considered less risky than others.
Types of Anesthetics
For a short procedure, a dog may be sedated using an injected anesthetic. For particularly lengthy or painful procedures like eye surgery, the dog may require the stronger effects of an inhaled anesthetic. While the concentration of injectable formulas is determined by your dog's size, and the effects less precise, oxygenated or gas-based anesthetics can be adjusted quickly by the administrator during surgery in accordance to the dog's breathing patterns and the drug's visible effect.
While Under Anesthesia
The anesthetic administrator will carefully monitor your dog's vital signs while he is sedated, keeping track of his heart rate, pulse strength, respiratory rate and more. She may determine whether your dog is in a deep-enough state of sedation by monitoring reflexes and muscle tone, which tell her both whether the sedation is too strong and whether it is too weak, allowing her to make the necessary adjustments before beginning the actual surgical procedure.
After your dog awakens from his sedation, he may continue to show side effects for several days. For example, because most general anesthetic drugs are easily absorbed by body fat, dogs storing more fat may retain the drug in their systems for a few days. Your pet may act confused, disoriented and forgetful, and he may have difficulty regulating his body temperature. Talk to your vet about the side effects of sedation and what you can do to prepare.