Clinically, cat anesthesia is one of the common surgical auxiliary methods. Anesthesia is also necessary in some major operations. Anesthesia also requires attention to the method and dosage, which requires veterinarians to have extremely high judgment and prediction during the operation. Accidents caused by anesthesia are not uncommon in pet surgeries nowadays. Excessive anesthesia or improper dosage can cause various complications. In severe cases, cats may die, so anesthesia is also a key issue.

Many people think that cat surgery means giving the cat a dose of anesthesia. This is completely wrong. Cat anesthesia and animal anesthesia are a complicated process. We humans usually have abnormalities, such as a cyst that needs to be removed somewhere, or cosmetic surgery that requires anesthesia. Often, a certain part will lose consciousness after just one injection. However, cats’ drug resistance is different from that of humans. , the person injects a small dose of anesthetic and nothing will happen, but the cat may be unconscious.

Therefore, as a surgeon, without the guarantee of anesthesia safety, the operation cannot be performed at all. We must conduct a detailed physical examination and assessment before surgery. During the surgery, we must shift the focus from the surgery itself to the anesthesia to nip problems in the bud and reduce the risks of anesthesia as much as possible. Only then can we provide patients who need surgery with Animals have an extra life guarantee.

Let’s first look at the steps of anesthesia.

1. Preoperative preparation and assessment

　1. Medical history

Known history of drug allergies, which drugs are being used, especially whether there is any major medical history. Many diseases will leave sequelae and cause harm to the operation. For example, long-term use of medication can cause excessive damage to the liver and kidneys; certain parasitic diseases can cause cardiovascular damage; canine distemper can cause damage to cranial nerves; lobar pneumonia and pleural cavity infection can cause excessive damage to the respiratory system, etc. ; Certain drugs can induce iatrogenic endocrine system diseases, such as Cushing's syndrome, diabetes, etc. Therefore, medical history investigation can reveal many things and allow doctors to be more alert in many aspects and prevent problems before they occur. Is there a history of drug allergies, especially narcotic drugs?

　2. Physical examination

Including palpation of the mouth, larynx, trachea, and abdomen; the three most basic indicators are body temperature, heart rate, and respiratory rate (T, P, R). Testing is required regardless of whether the animal underwent pathological or physiological surgery. It can be used as a reference value during anesthesia. For example, if the heart rate is too fast, the dose of atropine should be paid attention to when using preoperative drugs, or even not used. Auscultation reveals irregular heartbeats, rales, and abnormal breathing. Cats are generally nervous when they go to the hospital and have a fast heart rate. If atropine is injected before surgery to accelerate the heart rate, the heart rate will be further accelerated. An excessively fast heart rate will cause the heart to pump blood. The ability is greatly reduced, and in severe cases, collapse and shock may even be life-threatening. Therefore, many situations are analyzed on a case-by-case basis.

3.Age

Elderly cats may be at more risk of anesthesia due to cardiopulmonary and respiratory failure, and young cats may be at more risk of anesthesia due to hypoglycemia

　4. Character

Animals that do not cooperate with the doctor may be given an overdose of anesthesia due to an inability to conduct a thorough pre-anesthesia evaluation.

　5. Fasting

Fasting is required for 8 hours before surgery and water is strictly prohibited for at least 2 to 4 hours. For young animals or animals in the lactation period, the preoperative fasting time should be greatly shortened to 4 hours to avoid hypoglycemia before surgery.

　6. Risk assessment

Assessing the risk of an animal tolerating anesthesia and surgery, the degree of invasiveness of the procedure, the expected level of pain, the risk of major bleeding, and the risk of hypoglycemia are important factors in deciding which anesthesia to use.

2. Selection of anesthesia method

There are currently two main ways to anesthetize cats clinically, one is inhalation anesthesia, and the other is non-inhalation anesthesia.

　1.1. Inhalation anesthesia

Inhalation anesthesia is the first choice for pet anesthesia, and it is also divided into two categories.

　1.1.1 Induction of anesthesia

Propofol is used for intravenous induction, and its anesthetic effect time is 1 to 3 minutes, which is usually just enough to insert the endotracheal tube and connect to the respiratory anesthesia machine. To put it simply, the anesthetic drug that metabolizes the fastest in the body or wakes up the fastest can be said to be a good anesthetic drug. For this kind of anesthetic drug, after opening the bottle, it can only be used on the same day, and it cannot be used again the next day, and its price is very high.

　1.1.2 Inhalation anesthetics

The current representative anesthetic drugs are: halothane, ammoflurane, isoflurane (alkane), desflurane, and sevoflurane. Halothane can cause liver damage in rare cases, so it is no longer produced by manufacturers. Enflurane is slightly less effective than isoflurane, and its molecular structure is an isomer of isoflurane. However, the price difference between the two is very large. Enflurane is very cheap, while isoflurane is much more expensive. As for desflurane and sevoflurane, the prices are astonishingly high. Everyone should remember that the vaporizers used for different gas anesthetic drugs, that is, the anesthesia machines are different, and their performance and safety are also different.

　1.2 Non-inhalation anesthesia

Non-inhalation anesthetic drugs are mainly injection-type drugs. The faster they are metabolized in the body, the safer they are. Commonly used non-inhalational anesthetics include: 846 mixture, ketamine, meptanine, albuterol, propofol, acepromazine, diazepam, midazolam, thiopental, etc. It should be noted that even with injection anesthesia, necessary measures such as preoperative examination, airway patency, intravenous access establishment, and anesthesia monitoring cannot be ignored. ​​​​​​

3. Intraoperative monitoring

Main intraoperative monitoring of ECG, blood oxygen and body temperature

During the operation, the patient will be monitored by an ECG monitor or a dedicated person will perform heart and lung auscultation continuously to observe the condition of the eyeballs and pay special attention to the respiratory rate. Normally, when an anesthesia accident occurs, breathing stops first while the heart is still beating. If professionals detect respiratory abnormalities as early as possible and take measures as soon as possible, danger can usually be averted. In addition, if the heart rate decreases and the blood oxygen saturation continues to decrease during the operation, the cause should be found immediately and measures should be taken.

All pet hospitals should train specialized anesthesiologists to provide uninterrupted monitoring during the operation. All these are done for the safety of life.

4. Accidental rescue under anesthesia

At present, anesthesia accidents mainly focus on pulmonary edema, respiratory arrest, cardiac arrest, etc. Rescue measures must be timely and in place, which not only requires tacit cooperation between the surgeon and assistant, but also requires keeping a cool head. To achieve adequate rescue and tacit cooperation, you need to conduct repeated drills in normal times, but cannot wait until an accident occurs, otherwise it will be too late.

5. Wake up

Anesthesia records need to be kept during the recovery phase. Awakening begins with turning off the anesthetic drugs. Removal of the intubation does not mean the end of the awakening. The return of physiological indicators to close to normal means the end of recovery. Most anesthesia deaths occur during the recovery stage (cats account for 60%). Within 3 hours after the end of anesthesia, we must monitor heart rate, blood pressure, auscultation during recovery, and detect anesthesia in time. Unexpectedly, there will still be respiratory blockage during the recovery stage, and continuous oxygen supply is required. The intubation tube cannot be removed until the patient can actively swallow, which means the patient can actively protect his or her breathing passage. Cats undergoing oral and dental surgeries should lower their noses below their backs and keep the air bag slightly inflated when removing the intubation tube to help clear residual material. Pay attention to maintaining the body temperature, assess the cat's pain level after waking up, perform pain management, and provide adequate pain management and a comfortable recovery environment. Generally, the cat can be discharged from the hospital only after the cat is fully awake, has normal alertness to the surrounding environment, has a normal body temperature, and feels comfortable. .

6. Precautions

Many animals will vomit after being injected with anesthetics. When vomiting, just let the cat’s head lower, so that foreign bodies will not enter the respiratory tract and the occurrence of foreign body pneumonia can be avoided. The most serious problem caused by anesthetics is not whether your cat has just eaten or vomited; it is whether pulmonary edema occurs. This is the most deadly. If the rescue is not timely, it may be life-threatening. Many cats have emergencies when they arrive at the hospital, but must undergo surgery. In this case, there is no way to consider whether they have eaten. Of course, it is necessary to fast before surgery and limit drinking water. Cats have very strong digestive abilities, and food will be emptied in the stomach in about 3 hours., if the stomach is empty, there will be no vomiting. It is not recommended to drink water 2 hours before surgery. Water is the most dangerous because water can directly enter the trachea through the larynx and then enter the lungs, causing foreign body pneumonia. The solution is to clear the throat of chyme immediately after vomiting.

The best advice: stop feeding one meal before the operation, at least about 5-6 hours apart, and stop drinking water 2 hours before the operation.

Finally, after the cat is discharged from the hospital, the owner should also observe it at any time. If there is any situation, he must call the doctor as soon as possible. Don't delay it because of busy work or other reasons. Domestic cats are generally used to using cat litter to solve their urination and defecation problems. Therefore, when you take the cat home after surgery, you should place its cat bowl as close as possible to make it easier for it to go to the toilet. Prevent the occurrence of holding urine.