Tubus

A tube is a medical aid used in dogs to secure the airways and ensure ventilation during anaesthesia or in an emergency. The tube is inserted into the trachea to maintain oxygen supply during surgery or in critical situations. The process of inserting the tube is called intubation.

What is a tube?

A tube is a tubular instrument made of flexible material that is inserted into the trachea of a dog. It keeps the airways open and enables the lungs to be supplied with oxygen or anaesthetic gases.

The tube is mainly used in two situations:

1. During anaesthesia: Securing breathing and preventing aspiration (inhaling fluids or vomit).
2. In an emergency: In cases of airway problems or respiratory arrest to enable artificial ventilation.

Types of tubes

The choice of tube depends on the size of the dog, its condition and the type of procedure:

Endotracheal tube (ETT):

• The endotracheal tube is the most commonly used tube in veterinary medicine. It is inserted directly into the trachea.
• Cuffed tube: An endotracheal tube with an inflatable cuff (balloon) seals the trachea and prevents air or fluids from going in the wrong direction. The cuff protects against stomach contents entering the lungs.
• Cuffless tube: A tube without a cuff is sometimes used for small dogs or puppies, as their trachea is particularly sensitive.

Nasotracheal tube:

• This tube is inserted into the trachea through the nose and is particularly useful if the dog’s mouth cannot be opened or in cases of swelling in the neck area.

Orotracheal tube:

• An orotracheal tube is inserted into the trachea through the mouth and is used in most cases during anaesthesia or for artificial ventilation.

Laryngoscope:

• The laryngoscope is not a tube, but an instrument often used together with the tube to visualise the larynx and vocal cords and to insert the tube correctly.

Areas of application for tubes in dogs

Anaesthesia:

• A tube is used during operations under general anaesthesia to secure the airways and ensure a controlled supply of anaesthetic gases and oxygen. The tube also protects the dog from saliva, stomach contents or blood entering the trachea and endangering the lungs during the operation.

Emergency situations:

• In cases of airway obstruction, respiratory arrest or in dogs that can no longer breathe independently due to severe injuries or illnesses, a tube is used to maintain breathing and secure oxygen supply.
• In resuscitation situations (e.g. during cardiopulmonary resuscitation), intubation is used to perform efficient artificial ventilation.

Artificial ventilation:

• In dogs that require intensive care after surgery or a severe illness, a tube is used to connect them to a ventilator.

Tracheal operations:

• A tube is used during operations on the trachea or in cases of laryngospasm (involuntary contraction of the larynx) to keep the airways open during the procedure.

Procedure for intubation in dogs

Intubation is a medical procedure in which the tube is inserted into the trachea. It is performed by a qualified vet or veterinary assistant to avoid injuries or complications.

1. Preparation: The dog is usually placed under general anaesthesia or sedated to relax the muscles and avoid pain. During anaesthesia, the vet monitors the heart rate, oxygen saturation and breathing.
2. Insertion of the tube: The vet opens the dog’s mouth and uses a laryngoscope to see the larynx and vocal cords. The tube is inserted into the trachea through the glottis. If a cuffed tube is used, the cuff is inflated after insertion to seal the trachea.
3. Securing the tube: The tube is secured at the dog’s mouth with a band or string to prevent it from slipping. The vet checks the position of the tube and verifies whether the dog can breathe freely.
4. Monitoring during anaesthesia: During the operation or treatment, the dog is constantly monitored to ensure that the tube keeps the airways open and that no obstructions occur.

Risks and complications of intubation

Although intubation is a safe and frequently used procedure, some risks and complications may occur:

1. Injuries to the trachea: If the tube is too large or inserted improperly, it can cause injuries to the sensitive mucous membrane of the trachea, which may lead to inflammation or bleeding.
2. Incorrect intubation: In rare cases, the tube may be accidentally inserted into the oesophagus instead of the trachea, which prevents the dog from breathing effectively. For this reason, checking the position of the tube is crucial.
3. Aspiration: Despite the tube, aspiration can occur in rare cases, where fluid or stomach contents enter the lungs, particularly if the cuff is not properly inflated or if the dog vomits during anaesthesia.
4. Laryngospasm: Some dogs, particularly cats and small dogs, can develop a laryngospasm, in which the larynx contracts involuntarily. This can make inserting the tube more difficult.