Simply put, anesthesia is a controlled unconsciousness, where your pet's level of consciousness is controlled so they don't feel pain and don't move. Some veterinary procedures, such as dentistry and surgery, need to be performed with your pet under anesthesia. We certainly don't want our pets to feel pain whenever possible—and it's important that they don't move because precision is required during these procedures and movement could lead to complications.
Most healthy pets—even senior pets—don’t have any problems with anesthesia and, in general, the risks are more closely related to the procedure being done and your pet's general health than to the anesthesia itself. Like any medical procedure, anesthesia does have risks, but your veterinary team will take all of the necessary precautions to ensure that your pet is safe and can handle anesthesia. In an emergency, life-threatening situation, the risks of anesthesia are usually minimal compared to the risks of not performing the emergency procedure.
Prior to receiving anesthesia, your veterinarian will perform a thorough physical exam on your pet, review your pet’s medical history and discuss any risk factors. Your veterinarian may also perform blood tests on your pet to check for any indications of a developing medical problem or anesthetic risk. If you have any questions about your pet's health or his or her anesthetic risk, ask your veterinarian for an explanation that will help you make an educated decision.
Prior to anesthesia, your pet will likely be given a pre-anesthetic sedative to reduce his or her stress and ease the process. An intravenous catheter is usually placed to allow administration of fluids and medications. The anesthetic may be delivered by gas inhalation (using a gas anesthesia machine), intravenous infusion, or a combination of the two.
While under anesthesia, your pet will receive monitoring and care comparable to what you'd receive if you underwent anesthesia. This may include intravenous fluids and/or medications to support your pet's circulation and blood pressure; an endotracheal tube inserted into your pet's trachea (windpipe) to deliver the anesthetic gas and provide oxygen to your pet's lungs; pulse oximetry to measure the oxygenation of your pet's blood; blood pressure monitoring; temperature monitoring and warming blankets to prevent hypothermia (low body temperature); and electrocardiography (ECG, also called EKG) to monitor your pet's heart.
Once the procedure is done and it's time for your pet to wake up from the anesthesia, your pet will likely be placed in a quiet, semi-dark cage or kennel to recover. Pets are closely monitored during this time to make sure that they are recovering normally and that care is provided quickly if there are any problems. Pads and blankets are used to keep your pet warm during the recovery, but it's not uncommon to see a pet shivering while they recover from anesthesia; however, this doesn’t necessarily mean your pet is cold. Some pets may also vocalize (whine, bark or meow) during recovery. The endotracheal tube is removed when your pet is awake enough to swallow normally. Fluids and/or medications may be continued through recovery, depending on your pet's condition.
Depending on the procedure and your pet's medical condition, he or she may be sent home later in the day (once adequately recovered from anesthesia) or he or she may need to remain in the hospital.
What are the risks of anesthesia?
The risks of anesthesia should always be considered along with the benefits, and the risks and benefits of any alternatives to anesthesia should also be considered.
Anesthesia risks can run from minor problems, such as mild vomiting after recovery from anesthesia, to life-threatening problems such as cardiac arrest or stroke. Anesthesia-related deaths are rare, though, and while complications can occur, the veterinary team will take all of the necessary precautions to ensure that your pet is safe and can handle anesthesia. For elective procedures, there's more opportunity to postpone anesthesia if some risks that are present can be reduced by treatment prior to the anesthesia and procedure.
Anesthesia is considered "high risk" when your pet has health problems that may increase their risk of life-threatening complications while anesthetized. This is not a guarantee that your pet will experience such complications, but there is a higher chance that complications could happen. If your veterinarian considers your pet “high risk,” they will do everything they can to manage that risk. However, you should be prepared for the possibility that your pet may still develop life-threatening complications and could die, despite these best efforts.
How can you reduce your pet's risk?
- Let your veterinarian know if your pet has ever had a reaction to sedation or anesthesia
- Make sure your veterinarian is aware of all medications and supplements (including over-the-counter products) your pet is receiving
- Keep your pet healthy with regular preventive care
- Keep your pet at a healthy weight
- Take steps to prevent injuries to your pet whenever possible (avoiding emergencies that may require anesthesia)
- Follow your veterinarian's instructions before anesthesia, especially with regards to withholding food and/or water
- Follow your veterinarian's instructions regarding any medications you should—or should not—give to your pet prior to anesthesia
Talk to your veterinarian about the protocols for anesthesia at the clinic: what happens, who's involved, and how your pet will be taken care of afterward. Your veterinarian can discuss the procedure and protocols with you, which will help set your mind at ease. If your pet is at high risk for anesthesia or has had previous anesthesia complications, your veterinarian may choose to consult an anesthesia expert at www.ACVAA.org or may refer you to a hospital with a board-certified anesthesiologist on staff.
The AVMA would like to thank Dr. Nora Matthews and the American College of Veterinary Anesthesia and Analgesia for their contributions to this page.