Is Anesthesia Safe?
General anesthesia is used on a daily basis in most veterinary hospitals. A common conversation with clients is over concern regarding the safety of anesthesia for their pet. The good news is that modern anesthesia is very safe. Today we have access to much better drugs. This allows us to tailor the anesthetic plans to each patient’s individual needs. The risk of a pet dying under anesthesia is less than 1%. The rare patients that are lost under anesthesia are generally emergency procedures, when the patient’s condition is already extremely critical prior to surgery. The risk of a pet dying under anesthesia while undergoing a routine procedure, such as a spay, neuter, dental or mass removal, is extremely low. This risk can be affected by the anesthetic drugs used, as well as the monitoring of the patient during the procedure, as well as the recovery period.
The following is a list of questions that you should ask your veterinarian before scheduling any procedure involving anesthesia for your pet:
1) Is pre-anesthetic blood screening performed?
All patients, not just old or sick patients, should have basic pre-anesthetic blood tests performed prior to any anesthetic event. This testing will provide your veterinarian with important information regarding organ function (the kidneys and liver must be healthy to allow a patient to metabolize and excrete anesthetic drugs), as well as screen for infection, anemia or a low platelet count (which would affect a patient’s ability to clot during a surgical procedure). Often times, certain anesthetic protocols or treatment modalities can be used to tailor an anesthetic plan for a patient’s specific needs based on labwork findings. Your veterinarian may even elect to delay a procedure if undesirable results are obtained, or if further testing and treatment are warranted before anesthesia is used. Even in young patients (less than 1 year of age), bloodwork will occasionally detect abnormalities that could affect their ability to handle anesthesia.
Many drugs commonly used for general anesthesia tend to cause a drop in blood pressure. Intravenous fluid therapy can be used to maintain a safe blood pressure throughout an anesthetic event. In addition, an intravenous catheter allows for immediate administration of emergency drugs for resuscitation if an adverse reaction occurs during anesthesia.
3) Is the pet’s body temperature regulated during and after anesthesia?
All animals, especially cats, small dogs and older patients, lose a lot of body heat while under anesthesia. This leads to hypothermia, which can slow anesthetic recovery. Warm air blankets are commonly used to maintain a patient’s body temperature during anesthesia. Conventional heating pads are risky because they can cause serious burns.
Intubation means that the patient has an endotracheal tube (breathing tube) placed through the mouth and into the trachea (or windpipe). This tube is used to administer gas anesthetic and fresh oxygen to the patient, and allows controlled respirations if the patient is not breathing well on their own. The endotracheal tube also prevents accidental aspiration (or inhalation) of stomach contents if the pet vomits while under anesthesia, which is a potential side-effect of some anesthetic drugs. Endotracheal tubes should always be used during dental procedures, without exception, as they serve to prevent water from the cleaning and harmful bacteria from entering the lungs.
5) What type of pain management is used?
Surgery is always painful, and animals feel pain just as humans do. In modern anesthetic protocols, we strive to achieve pre-emptive analgesia, by blocking the pain pathways before the painful procedure begins. We also use balanced anesthesia to block the pain pathways from as many directions as possible. This will often involve nerve blocks, epidurals, localized injections of lidocaine, etc. These types of techniques allow for us to use less general anesthesia to keep the patient comfortable and asleep during procedures, which is obviously much safer for the patient as well.
6) What monitoring techniques are used?
It is critical to monitor the patient’s vital signs while under anesthesia to ensure that the respiratory and cardiovascular systems are functioning well, and to ensure that the patient is not anesthetized too lightly or too deeply. There should always be someone, besides the surgeon (who is occupied) that is providing dedicated, continuous observation of the patient while monitoring the heart rate, respiratory rate, and anesthetic depth. These parameters should also be recorded in a log, so that any undesirable trends or adverse events noted during anesthesia can be avoided in future procedures, ensuring the safety of the patient. Commonly used monitoring equipment includes:
– An electrocardiogram (EKG) to monitor the heart rhythm for arrhythmias
– A pulse oximeter to monitor the oxygen saturation of the blood, which should remain close to 100%
– A blood pressure monitor
– A machine (capnograph) to monitor the respiratory rate and carbon dioxide level
Another concern many pet owners have is the cost of anesthesia. As you can see, modern anesthesia involves a lot of equipment and expertise when performed safely, and unfortunately this costs money. Cutting corners by not performing pre-anesthetic blood screening, not intubating patients, not keeping patients warm, or skimping on pain medications and monitoring can save money, but the price is decreased comfort and safety for your pet. At The Pet Hospitals, we strive to provide the highest standard of care for your pet to ensure that they remain healthy and happy.
Dr. Christie Taylor
The Pet Hospitals- Lakeland