The following information is based on our expert experiences at NARKOVET CONSULTING® and information provided by the American Veterinary Medical Association (AVMA), the American College of Veterinary Anesthesia & Analgesia (ACVAA), and the American Animal Hospital Association and can be found in part on the websites of the AVMA and ACVAA.

When Your Animal Needs General Anesthesia

Some veterinary procedures need to be performed with your animal under general anesthesia (for example: dentistry, surgery, and some diagnostic imaging). Simply put, general anesthesia is a controlled state of unconsciousness, where your animal’s level of consciousness is controlled so it does not feel pain and does not move. We certainly do not want our animals to feel pain whenever possible, and it is important that they do not move because precision is required during these procedures and movement could lead to complications. Most healthy animals do not have any problems with general anesthesia and, in general, the risks are more closely related to the procedure being performed and your animal’s general health than to the anesthesia itself.

Most of us are anxious about undergoing general anesthesia ourselves, so it is understandable to be concerned about your animal being anesthetized. Over the past four decades veterinary anesthesia has made tremendous progress and is safer than it ever was before, and a well-trained veterinary team further reduces your animal’s risk. There are also increasingly more anesthesia specialists available who offer consultation services and provide anesthesia services at the specialist level. Diplomates of the American or European College of Veterinary Anesthesia & Analgesia are Doctors of Veterinary Medicine who have completed advanced specialty training in anesthesiology and have passed a board exam certifying them as experts in the anesthetic care of veterinary patients. Many of them offer assistance and consultation services upon requests by your veterinarian or yourself.

Like any medical procedure, anesthesia does have risks. These risks can run from minor problems, such as mild vomiting before induction or after recovery from anesthesia, to life-threatening problems such as respiratory or cardiac arrest. Anesthesia-related deaths are overall rare, though, and while complications can occur, a well-prepared veterinary team will take all of the necessary precautions to ensure that your animal is safe and can handle anesthesia. The risks of anesthesia should always be considered along with the benefits, and the risks and benefits of any alternatives to general anesthesia should also be considered. In an emergency, life-threatening situation, the risks of anesthesia are usually minimal compared to the risks of not performing the emergency procedure. For elective procedures, there is more opportunity to postpone anesthesia if some risks that are present can be reduced by treatment prior to the anesthesia and procedure.

Before Anesthesia

Prior to receiving general anesthesia, your veterinarian and anesthesia team will perform a thorough physical exam on your animal, review your animal’s medical history and discuss any risk factors. Your veterinarian may also have blood and/or other diagnostic tests on your animal performed to check for any indications of a developing medical problem or anesthetic risk. If you have any questions about your animal’s health or the anesthetic risk, ask your veterinarian for an explanation that will help you make an educated decision.

Trips to veterinary health care provider, unfamiliar people, smells, and other animals in the waiting area or other locations as well as the handling by veterinary staff your animal is not used to can be quite stressful. Therefore, most animals require sedation to calm them and decrease stress before general anesthesia. After reviewing your animal’s medical history and performing a physical examination on the day of surgery, the veterinary team will determine which medications will be given. An intravenous catheter will usually be placed to allow administration of fluids and medications. The anesthetic is commonly delivered by intravenous administration, gas inhalation (using a gas anesthesia machine), or a combination of the two.

During Anesthesia

While under general anesthesia, your animal will receive monitoring and care comparable to what you would receive if you underwent general anesthesia. This may include intravenous fluids and/or medications to support your animal’s circulation and blood pressure; an endotracheal tube inserted into your animal’s trachea (windpipe) to deliver the anesthetic gas and provide oxygen to your animal’s lungs; pulse oximetry to measure the oxygenation of your animal’s arterial blood and tissue perfusion; blood pressure monitoring; temperature monitoring and warming blankets to prevent hypothermia (low body temperature); and electrocardiography (ECG, also called EKG) to monitor your animal’s heart rhythm. For complex interventions or if you animal is really sick, additional monitoring modalities may be considered to help assessing your animal’s vital organ function during and after general anesthesia.

After Anesthesia

Once the procedure is done and it is time for your animal to wake up from the anesthesia, your animal will likely be placed in a quiet, semi-dark cage or kennel to recover. Animals are closely monitored during this time including assessment of pain 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 animal comfortable and warm during the recovery period, but it is not uncommon to see an animal shivering while it recovers from anesthesia; however, this does not necessarily mean your animal is cold. Some animals may also vocalize (whine, bark or meow) during recovery. The endotracheal tube is removed when your animal is awake enough to swallow normally. Fluids and/or medications may be continued through recovery, depending on your animal’s condition.

Depending on the procedure and your animal’s medical condition, it may be sent home later in the day (once adequately recovered from anesthesia) or it may need to remain in the hospital for further observation and treatment.

Not so many years ago veterinarians would not operate on animal patients they considered too old or too sick to tolerate the stress of anesthesia and surgery. Today, however, animals of every age – from the newborn to the very old – and of any health situation – from the healthy to the severely compromised – may undergo anesthesia relatively safely for surgery and diagnostic procedures.

Here are 10 questions about the anesthesia of your animal you may want to ask your animal health care provider before you provide permission for the procedure to be performed in your animal.

1. Does my animal truly require general anesthesia to perform the anticipated procedure?

   Many surgical or diagnostic procedures that are performed in the human patient may only require sedation and local or loco-regional anesthesia, while animals may not tolerate those interventions without general anesthesia. Nevertheless, more recently developed sedation protocols as well as more sophisticated techniques of local and loco-regional anesthesia and analgesia allow nowadays many more procedures to be performed also in animals without necessarily the need of general anesthesia. The decision whether or not a sedation and local anesthesia technique is a viable alternative to general anesthesia for your animal will be made by your veterinarian or the veterinary anesthesiologist based on their assessment of your animal during the preanesthetic examination. It is important to know that also sedation and local or loco-regional anesthesia techniques carry risks and those must be weight against the benefits but this applies to general anesthesia as well.

2. Who will be giving anesthesia or sedation to my animal?

   It’s important to find out who will be in charge of your animal’s anesthesia or sedation care. Under most optimal circumstances, a veterinary anesthesiologist (a Doctor of Veterinary Medicine who specialized in anesthesia and analgesia care) will be personally taking care of your animal or will supervise an Anesthesia Care Team that takes care of your animal. The team may include registered veterinary nurses (RVNs) or technicians (RVTs, RAHTs), residents, interns, junior veterinarians. In most hospitals or practices a veterinarian specialized in disciplines other than anesthesia (surgery, ophthalmology, dentistry, diagnostic imaging, medicine, etc.) or the veterinary practitioner performing the procedure will oversee the anesthesia care provided by one member of the Anesthesia Care Team. It is critical that all members of the Anesthesia Care Team involved in taking care of your animal have received adequate education in anesthesia and pain treatment and that this can be document. In some countries such as the USA and Canada, the United Kingdom, or Switzerland highly qualified animal nurses or technicians with advanced training in veterinary anesthesia (Veterinary Technician Specialist in Anesthesia (Academy of Veterinary Technician Anesthetists (AVTA) certified), nurses with Diploma in Advanced Veterinary Anesthesia Nursing (Royal College of Veterinary Surgeons (RCVS) approved), or Veterinär-Anästhesie-Techniker (Frei’s Schulen–certified) who provide anesthesia care under oversight of the veterinarian performing the surgical or diagnostic procedure.

3. What is the chance of a serious complication from anesthesia?

   Better medications and monitoring equipment have made anesthesia remarkably safer than even a few years back, which is why veterinarians can offer anesthesia today even to very old and sick animal patients. A better question to ask would be this: What is the chance of my animal developing complications from the whole experience of anesthesia and surgery? Your veterinarian should be able to answer this question in general but also for his/her practice or hospital in particular.

4. What will the Anesthesiologist or Anesthesia Care Team need to know?

   You will be asked important questions about your animal’s general health, body weight, eating and drinking behaviors, any medications you are administering to your animal, any previous diseases or injuries your animal may have had in the past, any surgeries your animal may have had in the past, any difficulties with anesthesia in the past, or trouble exercising. The internal organs of greatest concern are the brain, liver, kidneys, heart, and lungs. Blood and other tests may be ordered to evaluate how well the body systems are functioning prior to anesthesia. Knowing how well your animal’s internal organs are functioning will help your veterinarian and the Anesthesia Care Team plan your animal’s anesthesia. Veterinary anesthesiologists are trained to administer anesthetics to animal patients that are sick, injured, pediatric, geriatric, or healthy and to deal with complications should they occur.

5. Which medication, if any, will my animal receive prior to inducing anesthesia?

   Based on your animal’s medical history and a physical examination performed prior to surgical or diagnostic intervention, your veterinarian and the Anesthesia Care Team will decide on which drugs are best suited as premedication agents to help your animal to become more sedate, calm and less painful. In large animals it is usually unsafe to the animal as well as the veterinary personnel to induce anesthesia without prior sedation and pain relief and dependent of the underlying health problem (for example bone fracture in one leg) it might be advisable to induce anesthesia in a sling or against a tilt table to avoid any further trauma to occur. Veterinary anesthesiologists are usually familiar with those techniques. The less stressed and painful the animal is the lower the dosing requirements for anesthetic medications. Preanesthetic medication may also include antimicrobials and antiinflammatory drugs. Let your veterinarian or the veterinary anesthesiologist tell you which drugs the Anesthesia Care Team is planning to use so that you can report any problems your animal might have had in the past with one or more of those agents.

6. Should I give medicines to my animal on the morning of anesthesia?

   Veterinarians may differ in their opinions on this question but also the type of medicine you are administering to your animal on a routine basis may make a difference. Therefore it is important to make your veterinarian aware of all medicines your animal is receiving on a routine basis and to ask which adjustments to drug dosing, if any, you should make the night before or day of anesthesia. It is always a great idea to bring a list of your animal’s medications and doses, as well as a written summary of your animal’s medical conditions and previous veterinary care when you discuss the treatment of your animal with your veterinarian.

7. Does a breathing tube have to be used during the operation?

   For most major operations under general anesthesia including dental procedures, a breathing tube is necessary. Usually, it is inserted into the trachea (windpipe) after the animal is unconscious and taken out at the end or relatively soon after surgery or a diagnostic procedure. In general anesthesia, your animal is unconscious and has no awareness of other sensations. For many minor procedures or diagnostic tests, sedation alone might be enough and a breathing tube is often not needed but still enrichment of the inspired air with oxygen using an oxygen mask might be warranted as it is warranted during anesthesia. Sedation is a semi-conscious state that allows your animal to be comfortable during surgical or medical procedures and commonly feel less pain. There are three stages of sedation: minimal, moderate and deep. Also when your animal is undergoing sedation, you may ask who is monitoring it during the period of sedation and which vital parameters are being monitored. If you ever were told that it was difficult to insert a breathing tube in your animal during a previous operation, be sure to tell your veterinarian or the veterinary anesthesiologist so that special airway equipment can be ready for use in your animal. This can happen, for example, because your dog belongs to one of the brachycephalic breeds or your horse is a roarer, i.e., suffers from laryngeal hemiplegia.

8. Which vital parameters are being monitored during general anesthesia of my animal?

   To reduce anesthesia- and surgery-related complications anesthesia experts emphasize the importance of vigilant and sophisticated monitoring of animals undergoing general anesthesia. Guidelines formulated by the American College of Veterinary Anesthesia & Analgesia and similar specialty organizations have been published since 1995 and have been updated on a regular basis. These guidelines ask for continuous electrocardiogram (ECG) recording, non-invasive or invasive blood pressure monitoring, respiratory function (ventilation) and blood oxygenation monitoring with data recording at regular intervals (every 5-10 minutes) in all animals assessed to be suffering from a systemic disease (physical (ASA) status III or higher) and/or undergoing inhalant anesthesia and/or being anesthetized for longer than 45 minutes. They also ask for a veterinarian, technician, or other responsible person, solely dedicated to managing and caring for the anesthetized animal patient during anesthesia, who remains with the animal patient continuously until the end of the anesthetic period and monitors the animal also during recovery from anesthesia. Ask your veterinarian or veterinary anesthesiologist how monitoring of your animal will be handled after anesthesia has been induced.

9. How will my animal recover from anesthesia?

   Awakening from general anesthesia can be rather frightening to animals not understanding what just had happened to them or not being familiar with the environment in which they are awakening. Therefore your veterinarian and the Anesthesia Care Team are continuing to carefully monitor your animal throughout this phase, which will include watching out for signs of pain. Many factors have an impact on how your animal will behave during recovery. There is for once the character of an individual animal like yours but also species-, breed-, gender- and age-related factors play a role. In addition your animal’s underlying health problem, the surgical or diagnostic procedure performed, the anesthetic protocol used, the length of anesthesia and possibly pain as well as environmental factors like noise level, temperature, and brightness in the recovery room may all have an effect on how pleasant your animal is perceiving the awakening and thus how smooth the overall recovery from anesthesia will turn out. Your veterinarian or the veterinary anesthesiologist and the Anesthesia Care Team can assist your animal in many ways during recovery. This may include providing padding (or mattresses) and blankets to keep your animal comfortable and warm, additional medications to treat excitatory reactions and pain as the anesthetics start to wear off, or even physical assistance to help your animal getting back on its feet. For large animals specific techniques have been developed to assist an animal recovering from anesthesia and to get back on its feet with the least risk of injuring itself. Also oxygen supplementation and continued administration of intravenous fluids and other medications may be indicated to help your animal to recover as best as possible from anesthesia. Ask your veterinarian or veterinary anesthesiologist how your animal will be handled during the recovery period and which precautions are being considered to prevent complications or treat them should they occur. For horses and other large animals.

10. How is pain controlled during and after anesthesia and surgery?

    Whenever a veterinary anesthesiologist is taking care of your animal’s sedation or general anesthesia this expert will be responsible for pain control in the period before, during and immediately after anesthesia and surgery. In other situations the veterinarian overseeing the Anesthesia Care Team or performing the surgical or diagnostic procedure will prescribe a treatment plan for your animal’s pain. Analgesics given already as part of the premedication drug regimen before induction of anesthesia or during anesthesia as an intravenous infusion or repeated drug boluses can help to significantly reduce the requirement for anesthetic drugs and perception of noxious stimuli during the intervention. Likewise local nerve blocks used to numb the operative field can help reduce the dosing need for anesthetic drugs, as can loco-regional anesthesia or analgesia techniques such as an epidural analgesic drug administration help minimize the amount of anesthetic drugs needed to keep your animal anesthetized. The same “pain-killing” injections or techniques are commonly used post-operatively, but other methods of providing analgesia may be used such as epidural or local nerve blocks or placement of a “pain patch”. Relieving the pain and stress associated with the surgical procedure is a priority for the anesthesiologist and/or Anesthesia Care Team. Veterinary anesthesiologists are specifically trained to manage pain.

Talk to your veterinarian and address the questions listed above. Your veterinary health care provider will discuss the procedure and protocols with you, which will help set your mind at ease and give an educated consent. If your animal is at high risk for anesthesia or has had previous anesthesia complications or requires otherwise particular attention to its anesthetic management, your veterinarian may choose to consult with an anesthesia expert or may refer you to an animal health care facility with a board-certified anesthesiologist on staff. Your veterinarian may also contact our board-certified anesthesiologists regarding the anesthesia and pain care of your animal – we will respond with no delay!