Technique and clinic of general anesthesia. How difficult it is for dogs to endure and recover from anesthesia
- How long does it take for a dog to wake up from anesthesia?
- What to do during the recovery phase?
If you have to go to work and your pet is awaiting surgery, the question arises how long medications will affect the pet and how long it will take him to wake up from anesthesia.
It is important to know that pain relief lasts on average 24 hours.
This does not mean that the dog will sleep for 24 hours, but in general the procedure goes between induction, anesthesia, awakening and disposal general anesthesia usually takes the whole day.
This clarification is addressed especially to those owners who, seeing that the pet has woken up, think that the anesthesia has worn off and are ready to feed the animal or take it for a walk. And then, when the dog moves slowly or vomits, they begin to panic.
When should an animal wake up from anesthesia?
It all depends on the type of anesthesia. The effect of injectable anesthetics or other gases lasts much longer, but here too we must provide clarification. In both cases, anesthesia covers not only the operating period, during which operations can be performed, but also the awakening phase.
During the awakening phase, the dog gradually begins to recover motor functions and sensitivity appears, but recovery is complete only after 24 hours.
So don’t be surprised if, after an operation that was done in the morning, when night comes the dog still moves a little hesitantly and seems to be looking into space. This is fine. And don't be alarmed if your vet tells you that your dog needs to be locked in the room all night so they're still under anesthesia.
What to do during the recovery phase?
The first stage of awakening, namely regaining consciousness and acquiring motor function, usually occurs under the supervision of a veterinarian. Most doctors keep the patient in the clinic during the day in order to keep him under control.
When your veterinarian discharges a dog, you should be informed about how to behave with the animal, when to take it for a walk, and when to feed it.
You can feed and water your dog after anesthesia only if you are sure that all reflexes have been restored. Usually you can drink after 5-6 hours, and eat after 10-11. Don't be alarmed if you may vomit during this period.
Often, veterinarians will send the pet home in a sleeping state, giving subsequent instructions on how to behave.
However, if you know about side diseases or breed characteristics (weak heart, respiratory system, congenital anomaly), it is better to stay in the clinic until the animal gets back on its feet. It’s not the most pleasant thing to be left alone with your pet when unforeseen situations arise and you simply don’t know how to help your friend.
Immediately after anesthesia:
- When the dog is not yet in control of himself, periodically massage his eyelids with light touches, away from the corners of his eyes, to moisten the cornea.
- Be sure to place the animal on the floor, on a warm bedding and cover it to avoid hypothermia, because After anesthesia, body temperature drops.
- Never leave an animal on a table or bed, because... A fall can cause fractures and other complications.
- Don't forget to constantly measure your dog's body temperature, pulse and breathing. If the temperature is very low, then it is necessary to warm the animal with a warm heating pad or apply plastic bottles, filled with warm (not hot!) water. However, remember that heat should not be applied to the operated area.
- Periodically moisten the lips with a wet cotton swab until the animal begins to drink on its own. You can drop water with a pipette, but only if the swallowing reflex is restored.
Complications after anesthesia
Our pets, who live in warm apartments, are usually pampered creatures, plus many are obese, so anesthesia for them is a rather serious test.
The most common complications are weakened breathing, a strong decrease in body temperature, and loss of consciousness. In these cases, it is necessary to urgently contact a veterinarian and get advice.
A weak thread-like pulse with intermittence, intermittent breathing, wheezing, breathing with an open mouth should alert you. You should contact your veterinarian immediately.
In the process of waking up, it may seem that the dog is already fine, because... can move, however, this is a misconception. At any moment, your pet may fall, hit itself, or bite its tongue.
Subsequently, some animals may experience a stroke or pulmonary edema during anesthesia, so carefully monitor the animal’s behavior for several days after surgery.
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General anesthesia in dogs is used not only in cases of surgical intervention, but also, for example, when it is necessary to strictly restrain restless or aggressive animals, as well as to eliminate the risk of significant stress for the pet. Such measures significantly reduce the time of treatment or diagnostic procedures, ensuring effectiveness and safety for the dog.
If your pet's health condition requires surgery, there is a good chance that the anesthesiologist will consider necessary use general anesthesia for a dog. Such a decision usually causes concern among pet owners, but specialists at the Pride Veterinary Center are ready to destroy the myth that general anesthesia is dangerous for a dog.
In order to ensure complete safety of the animal during the use of anesthesia for dogs, we comply with two simple rules: the best equipment and the best anesthesiologists. This combination allows us to minimize the risk of human error by optimizing the process of putting the dog in and out of anesthesia - we monitor all vital signs in real time and immediately correct the situation at the slightest deviation from the norm.
Anesthesiologists at the city veterinary oncology center Pride carefully monitor new innovations in veterinary medicine and implement best solutions on practice. Last year, the clinic added a BIS monitor that allows you to monitor the patient’s depth of anesthesia, and this year we began using a Fisher & Paykel gas mixture humidifier to make it possible for the dog to maintain the required body temperature while under anesthesia.
Of all existing methods When administering anesthesia, we give preference to the most modern and safe method - inhalation (gas) anesthesia. Gas anesthesia for a dog does not affect the functioning of the kidneys and liver, its effect on the animal’s body is minimal.
Anesthesia for dogs - drugs
According to the methods of administration, three types of anesthesia can be distinguished: intravenous or intramuscular, inhalation (gas), local.
Depending on the goals and objectives, the anesthesiologist selects the optimal type of anesthesia for dogs. The drugs are selected based on the individual properties of the pet’s body.
IN veterinary center Pride uses only advanced drugs for anesthesia in dogs: Domitor, Zoletil, Propofol. Preference is given to inhalation anesthesia, for which Isoflurane and Sevoflurane are used. More recently, the clinic has become able to use xenon, which today is considered the safest and “mildest” drug for gas anesthesia in terms of its effect on the animal’s body.
Dog after anesthesia
In the first few hours after the operation, careful care of the animal is necessary, since the dog after anesthesia will not be able to stand and move confidently - provide it with maximum rest. 4-6 hours must pass from the moment the pet regains consciousness, only after this is it allowed to feed and water the dog, but subsequently the animal must have Free access to clean water.
Complications after anesthesia in dogs
Every animal's body has individual characteristics, therefore, no doctor can guarantee the absence of complications after anesthesia in dogs.
Experts warn that the consequences of anesthesia in dogs can be the following: slow breathing, heart palpitations and awakening, low temperature bodies.
The Pride City Veterinary Oncology Center has equipment that can significantly reduce the risk of complications after anesthesia in dogs. In particular, we are the only ones in Russia who use a BIS monitor to fully monitor an animal’s vital signs during surgery. The use of such a device eliminates the possibility of early awakening and makes it possible to select the exact dose for each dog, depending on the size of the animal and the characteristics of its body.
How long does it take for a dog to recover from anesthesia?
It is difficult to give an exact answer to the question of how long it takes a dog to recover from anesthesia, because the time required for the animal to regain consciousness depends on the nature of the surgical intervention and the individual vital signs of the animal. As a rule, complete recovery occurs within 24 hours.
5.1. Choosing the type of anesthesia
The choice of type of anesthesia depends on age and general condition the sick animal, the scope of the surgical intervention, the technical capabilities of the clinic (availability of anesthesia equipment, medication provision, etc.), and the qualifications of the doctor.
The age of the animal is very important, because puppies and kittens have increased metabolic processes, a relatively large surface area skin, imperfect thermoregulation, easily vulnerable mucous membrane respiratory tract, oxygen consumption and airway resistance are increased, which forces the respiratory system to work almost “to the limit.” The liver and urinary system are not functionally developed, so there is real danger drug overdose. In animals old age on the contrary, metabolic processes are reduced, age-related functional and organic changes are noted in all organs and systems; As a rule, there is damage to the cardiovascular, respiratory systems, and hepatic-renal failure, which makes the threat of death of the animal real during anesthesia or in the immediate post-anesthesia period. It is necessary to take into account the general condition of the animal, functionality organs and systems. In case of violations metabolic processes, liver and kidney functions, if possible, preference should be given to local types of anesthesia. Minor operations on the limbs (especially if there is concomitant diseases) is best performed under conduction, intraosseous or intravenous regional anesthesia. Surgeries on the pelvic organs, lower sections abdominal cavity can be performed using spinal anesthesia. It is necessary to operate on organs under general anesthesia. chest, upper sections abdomen, heavy bone damage(fractures of the pelvis, hip, shoulder).
Any anesthesia must be preceded by premedication.
5.2. Premedication
The main objectives of premedication are: sedative and potentiating effects, inhibition of unwanted reflex reactions, suppression of secretion of the mucous membrane of the respiratory tract, as well as the stomach.
A sedative effect can be achieved by using 1-2 tablets of aminazine, Nembutal, Luminal on the eve of surgery. If the operation is performed as an emergency, the animal can be administered droperidol, aminazine, seduxen, relanium, trioxazine. The introduction of these drugs also achieves a potentiating effect. Atropine is used to inhibit unwanted reflex reactions and to reduce secretion of the mucous membranes of the respiratory tract. Premedication is performed 15-40 minutes before anesthesia.
5.3. Carrying out anesthesia
The actual administration of anesthesia consists of 4 periods, the features of which are described below.
5.3.1. Introduction to anesthesia— switching off consciousness and achieving the required depth of anesthesia to perform endotracheal intubation or begin surgery (if intravenous anesthesia is used). Induction of anesthesia can be performed with preserved spontaneous breathing, followed by intubation. This period of anesthesia is the most dangerous and responsible for the anesthesiologist, because it is at this time that they most often occur various complications: vomiting, regurgitation, laryngo- and bronchiolospasm, arrhythmia, etc. Most often, barbiturates are used to induce anesthesia: hexenal, sodium thiopental. After intravenous administration of these drugs, tracheal intubation is possible. It should be remembered that barbiturates have a depressant effect on respiration and cardiac activity and have a weak analgesic effect.
5.3.2. Maintaining anesthesia. The general principle of this period of anesthesia is to adequately protect the body from surgical trauma. During this period, analgesics, narcotic drugs, muscle relaxants, artificial ventilation, vasoactive and cardiotropic drugs, solutions are used to correct disturbances in water-electrolyte and acid-base conditions, and maintain the volume of circulating blood at the required level. The choice of anesthetics and the arsenal of necessary medications depends on the specific situation, the general condition of the sick animal and the scope of the surgical intervention.
5.3.3. End of anesthesia. This period begins before the completion of the operation and is agreed upon by the anesthesiologist and surgeon. As a rule, the surgeon warns the anesthesiologist about the possible completion of the operation 15-20 minutes in advance. This allows the anesthesiologist to gradually eliminate certain components from anesthesia so that, with the final suture on the skin, all indicators of homeostasis (respiration, circulating blood volume, acid-base status, cardiovascular activity, blood pressure, etc.) are most fully restored. .). If anesthetics that are quickly released from the body (nitrous oxide, fluorothan) were used for anesthesia, its supply is stopped at the moment the last suture is applied; if the anesthetic is released slowly (ether), then within 10-20 minutes. until the end of the operation.
5.3.4. Post-anesthesia period begins from the moment the supply of anesthetic is stopped. At this time, it is necessary to remove saliva and mucus from the oral cavity, pharynx, trachea, and restore breathing (depth, frequency). Determine the degree of restoration of reflex activity (corneal, pupillary, laryngeal and cough reflexes), muscle tone and consciousness. After anesthesia, the animal must be warmed (covered warmly, if necessary, covered with heating pads), provided with the opportunity free breathing(pull out the sunken tongue, if necessary, insert or, conversely, remove the endotracheal tube), ensure observation of the animal until full recovery all vital functions.
5.4. Examples of general anesthesia
For dogs
Inhalation anesthesia. Premedication is given before the operation:
aminazine 1-2 ml of a 2.5% solution, diphenhydramine 0.5 ml, then 0.1 ml of atropine per 10 kg of body weight. With proper premedication, the dog becomes lethargic and drowsy within 10-15 minutes, negative reactions disappear, and dryness of the nose and mucous membranes of the oral cavity is noted. Breathing becomes smooth and deep
During this period, you can treat the surgical field (cut, shave, wash the skin). Aminazine can be replaced with morphine at a dose of 1-1.5 mg/kg (M. Zakievich recommends administering morphine at a dose of 1-10 mg/kg). After its administration, emptying of the stomach and intestines is observed (due to spasm of the sphincter muscles), which is of no small importance for further anesthesia. In very aggressive animals, intramuscular administration of sodium thiopental at a dose of 4-5 mg/kg over 30 minutes can be used for premedication. before the start of anesthesia. After fixing the dog on the table, 2-10 ml of 2.5-5% solution of sodium thiopental is administered intravenously until sleep occurs. Thiopental must be administered slowly and carefully until take a deep breath, then the rate of administration must be slowed down further until the animal exhibits convergent strabismus, and eyeballs 1/3-1/2 will not close with the third eyelid. At this time, the animal can be intubated (if possible, pre-administer 0.5-0.8 mg/kg of listenone). The endotracheal tube is connected to the apparatus and inhalation of fluorotane 0.5-0.7 vol.% is started, then the dose of fluorotane is gradually increased to 2.5-3 vol.% and, as soon as the animal reaches the stage of anesthesia III1-III2, the concentration of fluorotane is reduced up to 1-1.5 vol.%. Anesthesia is maintained with fluorotane in a dose of 0.1-0.5 vol.% together with oxygen and nitrous oxide (in a ratio of 1: 2). If necessary, analgesia can be enhanced by fractional administration of fentanyl at 0.1-0.15 mg/kg every 20-30 minutes. Relaxants, if they are administered, in the vast majority of cases last 1.5-2 hours. Usually this time is enough to carry out complex operations.
Ftorotan can be replaced with ether; in this case, it is necessary to increase the volume of anesthetic supply (see Chapter 2) and take into account the fact that the ether takes longer to be removed from the body, and therefore, at the end of anesthesia, the supply of ether must be stopped earlier - 15-20 minutes before the end of the operation.
The period of awakening passes faster with fluorotane anesthesia. The endotracheal tube should be removed only after adequate spontaneous breathing has been restored and reflexes have appeared. For severe myasthenia gravis, proserin is administered. Very often, after waking up, trembling is noted as a result of hypothermia and the residual effect of drug blockade of the thermoregulatory center. After the operation, the animal must be covered and warmed with heating pads. You should pay attention to the color of the tongue, the cyanosis of which indicates a violation of pulmonary ventilation and gas exchange.
Non-inhalational anesthesia. Premedication is carried out according to the previous scheme. For short-term minor surgical intervention, intravenous administration of 2-5 ml of a 2.5-5% solution of sodium thiopental and analgin 0.5-1 ml of a 50% solution (per 10 kg of body weight) is sometimes sufficient, which allows for 15-20 minutes. carry out minor surgical procedures (catheterization of the bladder, opening of small abscesses, primary surgical treatment wounds, etc.). The same anesthesia can be used when conducting X-ray examinations, especially in excited, angry animals, with extensive skeletal damage, in cases where the animal moves and does not allow X-ray examination. Sodium thiopental or hexenal can also be used for mononarcosis in another variant: 1 g of one of these drugs is injected intrapleurally or intraperitoneally. Sleep occurs within 3-5 minutes; surgical stage of anesthesia - after 5-10 minutes. and lasts up to 1.5 hours. A long-term drip infusion of a 1% solution in 200 ml of a 5% glucose solution with an injection rate of 30-40 drops/min is possible. This method of anesthesia is quite simple and effective, but it is poorly controlled, and the doctor must have sufficient experience to maintain a stable level of anesthesia.
Mononarcosis with ketamine intramuscular injection at a dose of 8-10 mg/kg allows minor surgical operations to be performed within 25-30 minutes. Fractional intravenous administration of the drug at a dose of 2-4 mg per kg of body weight is possible. After mononarcosis with ketamine, a state of psychomotor agitation is noted, which is relieved by seduxen and diazepam. Marek Zakievich (1994) recommends the following version of mononarcosis: intramuscular administration of sodium thiopental at a dose of 15 mg/kg with preliminary premedication with aminazine at a dose of 3 mg/kg.
Combined anesthesia. In our clinic, we most often use this type of anesthesia, because... it allows you to perform operations of any complexity and duration, does not require expensive equipment, gives excellent results and, with sufficient qualifications of the anesthesiologist, allows you to avoid many complications. Introduction to anesthesia is smooth, quick, without excitement, allows you to fix the animal in a position convenient for the surgeon and treat the surgical field. The use of various medications that potentiate mutual effects makes it possible to reduce their doses to a minimum.
The approximate arsenal and doses of medications used in our clinic are given in Table 1 (see pp. 84-85).
For cats
Anesthesia in cats is a rather complex problem. These animals are not suitable usual ways, used for dogs. And some medications cause a reverse reaction (for example, morphine), reducing body temperature by 1.5-2C (ketamine, xylazine, rompun). Below are examples various types anesthesia for cats used in our clinic.
Inhalation anesthesia. Premedication is carried out according to general principles. Cats are administered atropine at a dose of 0.05 to 0.1 mg per kg of body weight intramuscularly or subcutaneously. Aminazine at a dose of 2.5 mg/kg is administered intramuscularly or subcutaneously, 0.15 mg/kg - intravenously.
The simplest technically is mask anesthesia. The safest is anesthesia with nitrous oxide mixed with oxygen (2-3: 1), which allows you to achieve level III anesthesia. For analgesia, the concentration of nitrous oxide does not exceed 40-60%. However, abdominal operations It is quite difficult to perform anesthesia with this type of anesthesia due to the lack of muscle relaxation. In addition, upon completion of anesthesia, nitrous oxide is intensively released into the alveoli, displacing oxygen, which can lead to diffuse hypoxemia. Therefore, after the end of anesthesia, it is necessary for 2-3 minutes. give pure oxygen. This is shown schematically in Fig. 17.
Even simpler technically is inhalation mask anesthesia with ether. This type of anesthesia allows you to achieve the surgical stage of anesthesia with muscle relaxation. However, this type of anesthesia is not sufficiently controlled; there is a real danger of an explosion of the ether-oxygen mixture. With this type of anesthesia, a cone-shaped plastic or rubber mask with holes for air intake is used (Fig. 18). A gauze swab (foam rubber, cotton wool) soaked in ether is placed at the bottom of the mask; the mask is placed on the animal’s head and held in this position until the required stage of anesthesia occurs. After this, the mask is removed and put on again when necessary.
Combinations and doses of drugs used in combined drug addiction for dogs and cats
Table 1
| Drugs used | Route of administration | For dogs |
||||
| Atropine | 0.1-0.2 ml | 0,3 | 0,3-0,4 | |||
| Atropine | 0.1-0.2 ml | 0,3 | 0,3-0,4 | 0,4-0,5 |
||
| sibazon* | IV | 0.5 ml | 0,5 | 0,5 | 1,0 |
|
| Na thiopental | i/v fractionally | 100-150mg | 100-150 | 100-200 | 100-200 |
|
| Cordiamine | 0.5-1.0 ml | 0.5-1,0 | ||||
| aminophylline 2.4% Bemegrid | IV | 1.0ml | up to 2.0-3.0 | up to 4.0 | up to 5.0 |
|
The number of drugs used, their variability, dosage varies and depends on the following factors: a) the severity of the patient’s condition, b) his age; c) volume of surgical intervention; d) duration of anesthesia.
Continuation of the table. 1
| Drugs used | Route of administration | For dogs | For cats |
|||
| over 40 kg | Over 3 kg |
|||||
| Premedication for 30-40 minutes. (one of the combinations of these drugs is administered) | Atropine | 0,4-0.5 | 0,1 | 0,2-0,3 | 0,3 |
|
| Atropine | 0,4-0,5 | 0,1 | 0,2-0,3 | 0.3 |
||
| Induction of anesthesia (one of these drugs* is administered in combination with Na thiopental, or ketamine, or Na hydroxybutyrate) | sibazon* | IV | 1,0 | - | - | - |
| Maintenance of anesthesia (a combination of 2-3 drugs is used) | Na thiopental | i/v fractionally | 150-200 | - | - | 50-100 |
| Removal from medicated sleep(drugs are administered fractionally over 5-6 hours) | Cordiamine | 0,2-0,3 | 0,5-1,0 | |||
| aminophylline 2.4% Bemegrid | IV | 1,0 | ||||
* Drugs are administered in case of normal indicators blood pressure.
** Analgin is used as needed.
With this type of anesthesia, the development of all the complications described above is possible, so its use is limited.
During intubation, it is possible to use a combination of nitrous oxide, oxygen and fluorothane (in this case, fluorothane is supplied in a volume of 0.5-1 vol%). Exists real threat overdose of fluorotane, so the vaporizer must be perfectly calibrated
Non-inhalational anesthesia. The principles of premedication remain the same. Atropine is administered intramuscularly at a dose of 0.05-0.1 mg/kg, aminazine - 2.5-5 mg/kg (Marek Zakievich, 1994, indicates that the amount of aminazine can be increased to 5-10 mg/kg, at intravenous administration the dose is 0.15 mg/kg). For mononarcosis they use the following drugs: sodium thiopental intraperitoneally at a dose of 20-22 mg/kg and even up to 60 mg/kg (Marek Zakievich, 1994); hexenal - at a dose of 25-40 mg/kg of 1% solution causes anesthesia within 30-40 minutes; ketamine when administered intramuscularly at a dose of 20-25 mg/kg (A.D.R. Hilbery, 1989) causes a state of anesthesia after 5 minutes, which lasts 30-40 minutes Marek Zakievich (1994) recommends administering ketamine at a dose of 30-35 mg/kg, while the duration of anesthesia increases to 40-60 minutes. After recovering from anesthesia, the animal remains in a state close to a hallucinatory state for 5-8 hours. From our own observations, we can recommend the use of ketamine in a dose of 20 to 35 mg/kg, depending on the severity of the animal’s condition, the expected volume of the operation, and also depending on which company produced the drug.
Xylazine (Rompun) when used intramuscularly at a dose of 4.5 mg/kg causes anesthesia within 40 minutes. The animal fully recovers after 2-3 hours.
It should be remembered that all of the above drugs cause a decrease in body temperature by 1.5-2C, so it is necessary to take all measures to prevent this undesirable phenomenon (warming the animal with heating pads; maintaining the room temperature within 21-25C, etc.). In addition, xylazine causes vomiting, and the anesthesiologist must ensure that complications do not arise during this time.
Combined anesthesia. After the premedication described above, various combinations of drugs are possible. Approximate combinations and doses of drugs used in our clinic are given in Table 1 (see pp. 84-85).
Cats with urolithiasis and acute urinary retention is recommended next view combined general anesthesia: atropine - 0.1 mg/kg; ketamine - 10-15 mg/kg and rompun - 0.5 mg/kg. It is administered intramuscularly in one syringe. If it is necessary to prolong anesthesia, it is possible to use mask inhalation of nitrous oxide with oxygen, or ether.
For animals that experience urinary retention for more than 2 days, which is accompanied by serious metabolic disorders, we recommend that all manipulations be performed under presacral or sacral anesthesia.
Photo: Dog after anesthesia. Anesthesia for dogs
Today, veterinarians use general anesthesia for dogs quite often. With this measure, treatment or diagnosis occurs much faster with full guarantee of effectiveness and safety for the animal.
If your dog is undergoing surgery, then most likely the anesthesiologist will insist on general anesthesia. This decision can cause some anxiety and worry among pet owners, so we suggest that you study in detail the topic of anesthesia, which is covered in this article.
In veterinary practice, anesthesia for dogs is very popular, since these animals are quite restless and can cause harm to the attending physician. Indications for anesthesia are the following:
- carrying out long-term surgical intervention (cavitary or limb fractures)
- performing a range of diagnostic or cosmetic procedures
- any medical interventions in cases where the animal has big size and it is not possible to securely fix it
- examination of very aggressive animals
- cases when the dog can experience severe stress from the actions performed
How an animal is prepared for anesthesia
When there is a need to resort to surgical intervention, the animal will necessarily need to perform the following manipulations:
- donate blood for a detailed analysis;
- do an electrocardiogram of the heart;
- in some cases, an x-ray is performed and an ultrasound examination is prescribed.
Also, taking into account the condition of the four-legged patient, they resort to various therapeutic measures, the main goal of which is to minimize possible risks from anesthesia. They can take a few minutes or a couple of weeks.
The dog owner will also need to closely monitor his pet’s diet: it is forbidden to give food to the animal less than twelve hours before the surgical procedure.
Types of anesthesia for dogs
Today, several types of anesthesia for dogs are actively used. We will bring you detailed review the most popular types with their detailed descriptions.
Regarding the method of administering the anesthetic, anesthesia for dogs can be:
- intravenous;
- inhalation (gas);
- local.
Photo: When is anesthesia necessary for a dog? Features of intravenous anesthesia
In this method, drugs that provide elimination pain and induce sleep, enter the animal’s body directly into a vein using a special intravenous catheter.
This is the method of anesthesia used most of clinics where abdominal surgeries are performed. For intravenous anesthesia there is no need to purchase expensive equipment, which means it is a fairly economical option.
But it also has its negative sides, for example:
- blood pressure decreases
- heart rate decreases
- long-term respiratory depression is possible, and so on.
After intravenous anesthesia, the animal “comes to its senses” for a very long time, because it takes a lot of time to remove such anesthetics from the body (no less than several hours).
Until the dog wakes up from anesthesia, it should be closely monitored by veterinary specialists in order to promptly note any changes in its condition.
Inhalation (gas) anesthesia
In this case, anesthesia for dogs enters the animal’s body through inhaled oxygen using a special mask or endotracheal tube.
Small animals are placed in a gas chamber in which induction with an anesthetic is carried out.
But resort to this method is possible only in a situation where there is special equipment available, in the form of a gas evaporator, apparatus artificial ventilation lungs, as well as some other special devices.
It is much easier to administer an inhalational type of anesthesia than an intravenous one, since in this case the removal of drugs from the dog’s body occurs much faster.
As an independent type of anesthesia, inhalation anesthesia is usually used only for rodents and some exotic animals.
Features of local anesthesia
Local anesthesia is the most common method of pain relief, which is often used by doctors during appointments.
Regarding the technique of performing local anesthesia for dogs can be
- superficial
- infiltration
- conductive.
- Superficial anesthesia is mostly used when it is necessary to numb the mucous membranes using sprays. As a rule, then a 10% lidocaine solution is used. This technique has gained wide use in the field of humane medicine and is usually used when performing various manipulations in the oral cavity.
- Infiltration anesthesia can be achieved by injecting an anesthetic into the area around the area of planned manipulation. This method is actively used when it is necessary to suture small bite wounds, remove teeth, open abscesses, and so on.
- Conduction anesthesia - this can be achieved by injecting an anesthetic into the tissue located around the nerve. As a result, temporary nerve paralysis occurs and nerve impulses stop being transmitted. Thanks to this, complete anesthesia occurs in all organs and tissues spreading under the influence of this nerve. This method of local anesthesia is used exclusively in conjunction with sedation (usually intravenous anesthesia), since the most accurate administration of the drug is important. If it is not possible to completely immobilize the animal, then even the slightest movement will cause damage nerve endings, which in turn will provoke paralysis of the innervated zone.
Conduction anesthesia can be of the following types:
- epidural anesthesia;
- brachial plexus anesthesia;
- intercostal nerves;
- anesthesia of the nerves in the head area and so on.
In the case of epidural anesthesia, an anesthetic is injected into the area between the spinal cord and spine. In this case it is possible to achieve complete pain relief hind limbs together with the pelvic organs. By resorting to the described method it becomes possible to carry out surgical interventions to remove reproductive organs, also operations on pelvic limbs And bladder, and amputations.
When the anesthetic is injected into the brachial nerve plexus, it becomes possible to numb the limb on which the intervention is planned. This method is actively used when performing operations on the thoracic limbs.
The use of conduction anesthesia in the head area will provide pain relief to the gums, teeth, jaws and lips.
Anesthesia of the intercostal nerves is performed when various surgical interventions in the chest cavity are planned, as well as in the presence of rib fractures and the installation of drains.
What drugs are used for anesthesia?
To provide anesthesia for dogs, doctors often use a drug called Rometar. It acts as an adrenergic blocker, eliminating pain sensitivity, but does not cause sleep. The action of the drug is very similar to Propofol.
In addition, Ditilin and Ketamine are often used in surgical practice. The latter medicine can provoke a hallucinogenic dream, which does not have the best effect on subsequent mental state animal.
This list can also be continued with the currently quite popular drugs Antisedan and Domitor, which have a specific antagonist for quick fix effects of anesthesia.
If short-term procedures are planned, then anesthesia for dogs can be provided by Propofol (Deprivan), after which the animal gets back to its feet very quickly. To carry out such manipulations as biopsy or premedication, you can use Oxymorphone.
When agreeing to a surgical procedure using general anesthesia, every owner must know how the dog will feel after anesthesia, so as not to cause harm to its health.
When the animal returns home, it is important to carefully monitor it for another day so that if something happens, you can come to the rescue in time. The most important thing is to find a quiet and cozy place for your pet, where no one will disturb or irritate him.
It is not advisable to place the dog on the bed, because when the animal recovers from anesthesia, it runs the risk of falling off it and being injured. This even threatens postoperative sutures coming apart.
Photo: How a dog recovers from anesthesia The question you probably most often ask yourself is: “How long will it take for a dog to recover from anesthesia?” But, unfortunately, it is extremely difficult to answer correctly, because in this case everything will largely depend on the personal characteristics of the organism.
Some dogs return to a conscious state after two to three hours, while others will need to spend six to twenty hours “passed out.” Therefore, do not rush to panic if you notice that your dog is sleeping for a long time after surgery. If you cannot pull yourself together, call your veterinarian and discuss this issue again.
It should be separately noted that after anesthesia, the dog should not be given anything to drink for five to six hours, and should not be given food for approximately ten hours. This is due to the fact that when water and food enter the stomach, they will provoke vomiting reactions. If the animal begs to drink a lot, you can wet its tongue with water a couple of times an hour, but not more often.
Dog after anesthesia: what complications can there be?
Immediately before surgical intervention, the veterinarian must obtain written permission from the dog's owner that anesthesia will be performed. In addition, he must report any possible side effects.
In most cases, dogs after anesthesia are characterized by the appearance of:
- long sleep;
- allergic reactions to the drug used;
- decreased heart rate and slower breathing
- a strong decrease in body temperature.
It is also necessary to mention more serious complications, which can even be fraught fatal– pulmonary edema and postoperative stroke. To minimize the likelihood of these phenomena developing, it is important to perform a full diagnosis before surgery.
If the doctor refuses to perform a preliminary diagnosis, we do not recommend that you agree to surgery. It is better to find a more qualified specialist.
And when the operation is completed, be sure to ask the doctor about the question proper care looking after the dog after surgery. Indeed, in some cases, the animal’s condition is truly disgusting and it is your task to help the pet “come to its senses” as soon as possible.
Photo: Dog after anesthesia To summarize, when agreeing to anesthesia for your dog, you must be sure of the doctor’s professionalism, if necessary, familiarize yourself with his certificates, and also read reviews of other patients. Now the veterinary business is quite profitable and many unscrupulous doctors simply profit from their “patients” (or, to be more precise, from their owners). Therefore it is the choice good specialist will be one of the guarantees of success. Also, of course, we should not forget about preliminary diagnosis and proper post-operative care for a sick animal.
Diseases in dogs are not uncommon. Some of them can be cured in as soon as possible and with minimal losses, but to treat others you have to resort to surgical operations different levels difficulties. The problem is that the dog cannot be persuaded to lie still while the surgeon does his job. Even “minor” operations require anesthesia for dogs, and not only the success of the surgical intervention, but also the entire future life of the pet largely depends on the quality of its implementation.
Anesthesia comes from an ancient Greek term that can literally be translated as “lack of sensation.” This “lack” is achieved through anesthetic drugs that temporarily “turn off” the nerve fibers responsible for transmitting pain sensations.
In addition, anesthesia is characterized by a partial loss of muscle rigidity (that is, their relaxation), which also facilitates surgical intervention. All types of pain relief can be divided into two large groups: local and general (anesthesia).
General anesthesia for dogs
Regardless of the type of anesthesia, it always begins with premedication. This is the name of the “event” accompanied by the insertion of the lungs sedatives. Premedication is needed to calm the dog and prepare its body for deep, “full” anesthesia.
The absence of this stage is an almost 100% guarantee of the development of severe complications. General anesthesia can be divided into two broad types:
- Mononarcosis (monovalent).
- Polynarcosis.
In the first case, only one drug is used for anesthesia (occasionally two, if it is necessary to ensure their combined effect). As a rule, to such simple option are used for simple and short operations (many of which can be performed using only local anesthesia).
Accordingly, general polyvalent anesthesia involves the use of several drugs at once. It can be extremely difficult to take into account all the nuances of their interaction, but there is simply no other way out in cases where a complex and lengthy operation is ahead.
Parenteral anesthesia
This is the most common type of anesthesia, in which the active substance is administered intravenously into the dog’s body. The advantage of such anesthesia is the possibility of ideal dosing of the drug depending on the current condition of the animal being operated on. In addition, when administered intravenously, the medicine begins to act very quickly.
Important! Almost all drugs for this type of anesthesia can cause hypoventilation.
Simply put, the process of gas exchange in them slows down greatly, which is why the operated dog may well die by suffocating. It is for this reason that intubation is always performed (i.e., a special tube is inserted into the trachea through which air flows directly into the lungs).
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Intubation is not always used. There is no particular need for it when the operation itself takes no more than 10 or 15 minutes. The same applies to cases when the upper respiratory organs. True, even in such cases, the intubation apparatus is always kept at hand, since it may be needed at any time.
This is a pathology in which (due to congenital anomalies development of the vascular bed), blood from the gastrointestinal tract is sent directly to the general bloodstream. At the same time, the animal’s body is already in a state of chronic intoxication, and the introduction of sedatives intravenously can kill the dog.
Inhalation anesthesia
Currently, veterinarians use this technique quite actively. It is interesting that the first anesthesia was inhalation (it was given with chloroform vapor). Today this technique has changed somewhat, and couples active substance“pumped” into the lungs directly. To do this, the animal's trachea is intubated.
We can say that inhalation anesthesia is partly safer for the animal’s body, but still, in this case it is not without specific risks. Inhalation anesthesia is characterized by a significant drop in blood pressure (due to a pronounced vasodilator effect). During surgery, the dog's level must be constantly measured. blood pressure, since its drop to critically low values has an extremely sad effect on the condition of the kidneys and brain.
Inhalation anesthesia has at least one advantage - it allows easy access to many organs respiratory system. It is also what veterinarians prefer to use when it is necessary to operate on the eyes, ears, nasal or oral cavities of an animal. With high-quality spraying of the active substance, it is possible to reduce its dose as much as possible.
Interesting! Inhalation anesthesia is rarely used: it is used when it is necessary to perform particularly complex and lengthy operations, additionally using parenteral anesthesia.
Local anesthesia for dogs
The most common type. In veterinary medicine, local anesthesia is used daily and very actively. Divided into several varieties.
Application anesthesia
The simplest method. It consists of applying “freezing” substances directly to the surface of the skin or mucous membranes. Contrary to popular belief, the lethality of this type of anesthesia is quite high. So, today on the shelves of pharmacies you can find a lot of pain-relieving “sports” sprays, the effect of which lasts several minutes. This may be quite sufficient for a simple surgical intervention.
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Infiltration anesthesia
Also simple and effective method, which consists in saturating the layers of skin and subcutaneous tissue anesthetic solutions. This procedure is performed using a regular syringe. It is used when performing simple and fleeting operations: for suturing, for example, or when removing an abscess.
Regional anesthesia
One of the most difficult but effective ways local anesthesia.
- Firstly, its conductor type is distinguished. The meaning of the technique is to “impregnate” local nerve plexuses, nodes and nerve trunks with solutions of anesthetics.
- Secondly, anesthesia is spinal. It is performed by entering medicine directly between the arachnoid and soft membrane spinal cord. This method allows you to temporarily “turn off” all sensations below the injection site.
- The technique is good to use, for example, when caesarean section. In such cases, general anesthesia is extremely undesirable, since the “gave birth” bitch will need to feed the babies.
Epidural anesthesia
In this case, the drug is injected between the dura mater of the spinal cord and the spinal canal.
Contraindications for local anesthesia
It should be remembered that local anesthesia, for all its attractiveness (simplicity and low cost), they are not always used. The reason is the presence of serious contraindications:
- Local anesthesia is not used in cases where the operation (at least theoretically) may last longer than the duration of the painkiller.
- The animal has a tendency to develop allergic reactions (however, in this case, you need to be extremely careful with general anesthesia).
- Choleric character type. Simply put, it is better to immediately immerse “pocket” dogs with a quarrelsome and quarrelsome disposition into general anesthesia.
- The same applies to cases where the dog is large and strong. It is far from certain that the owner will be able to hold him and calm him down.
Recovery from anesthesia
The faster the animal recovers from anesthesia, the shorter the operation, the lower the dose of the active substance.
To remove the dog, the veterinarian gradually (!) stops supplying the medication; in some cases, they use special drugs, blocking the action of the main medication. In addition, pulmonary administration is recommended. pure oxygen: the latter helps accelerate metabolism and decomposition medicinal substances into its constituent components.
Risks and likelihood of complications
What are the possible complications of anesthesia? It is believed that sudden allergic reactions and intolerance to anesthetic drugs in normal conditions occur once in 100,000 uses. These reactions can range from mild swelling at the injection site to death.
Remember! Always and under all conditions, there is some chance that the body of a particular animal will react inadequately to a particular drug, even if the latter has been used for medical and veterinary purposes for decades.
In almost 100% of cases, problems will arise during general anesthesia (quite possibly fatal) if the dog has not “fasted” for at least 12 hours before the operation. A well-fed dog may die during surgery. The problem is that with general anesthesia, the principle of muscle innervation changes greatly.
