Endotracheal Tube Types

In humans, the trachea refers to the tube extending from the larynx to the bronchi. It is important for conveying air to and from the lungs. An endotracheal tube (ETT) is a flexible plastic tube that is inserted into a patient's trachea through the mouth or nose. This article discusses endotracheal tube types. 

Use of an endotracheal tube

An endotracheal tube maintains an open airway and facilitates ventilation (The endotracheal tube can be connected to a ventilator. A ventilator is a medical device designed to replace spontaneous breathing in patients who are unable to breathe adequately on their own). The endotracheal tube doesn’t always have to be used with a ventilator, for instance, in a bronchoscopy procedure, the patient can be allowed to breathe spontaneously, and the doctor will insert an endotracheal tube into the patient's trachea through the mouth or nose to secure an open airway for the passage of the instruments. The following illustrates what an ETT is.

Endotracheal tube types

There are various types of endotracheal tubes. Common types of ETT are discussed as follows.

1. Type classification based on where the ETT is inserted

A. An oral endotracheal tube is inserted into the trachea through the mouth. It is typically made of polyvinyl chloride (PVC) or other flexible, durable materials. It has a cuff, which is an inflatable balloon near the distal tip of the tube. When inflated, it seals the trachea to prevent air leaks and protect against aspiration. It has markings that indicate the insertion depth and position within the trachea.

B. The primary difference of a nasal endotracheal tube from an oral one is that it is inserted into the trachea through the nose rather than the mouth. It allows oral access and keeps the mouth free for surgeries, dental work, or other procedures.

2. Type classification based on material 

A. Rubber endotracheal tube: this type of tube is relatively hard and less flexible, so there is a risk of damaging the nasal passages, vocal cords, or tracheal mucosa during insertion.

B. PVC endotracheal tube: it is softened by the warmth of the upper respiratory tract, which helps ease tube passage. 

C. Silicone endotracheal tube has flexibility, which reduces friction with mucosal tissues and lowers the risk of injury.

3. Type classification based on function

A. Double-lumen endotracheal tube has two separate lumens, one for each lung. This allows independent ventilation of the right and left lungs. Double-lumen endotracheal tube is typically used in:

1) Thoracic surgery to facilitate lung isolation to operate on one lung while maintaining ventilation in the other.

2) Lung protection, namely to prevent contamination of healthy lung tissue during procedures on diseased lungs.

B. Irrigatable endotracheal tube has an irrigation port that introduces sterile solutions to wash away secretions. It also has a drainage channel that directs secretions out of the airway. Its benefits include reducing the risk of ventilator-associated pneumonia and maintaining airway hygiene in critically ill patients. Irrigatable endotracheal tube has applications such as:

1) When used in critical care, the tube minimizes the accumulation of secretions in patients requiring prolonged ventilation.

2) When used in infection control, it helps prevent respiratory infections by maintaining cleanliness within the airway.

C. Reinforced (armored) endotracheal tubes: this type of tube contains a spiral wire or plastic coil embedded in the tube wall. The benefits are being flexible and resistant to kinking. Its applications are as follows.

1) Used to provide a stable airway during procedures that require significant head or neck positioning, for instance in head and neck surgery.

2) Used in patients requiring extended ventilation support to prevent tube obstruction.

D. Standard endotracheal tube is designed for general airway management during anesthesia, critical care, and emergencies. It has the following features: 

1) A single channel for air passage.

2) Its cuff is an inflatable balloon near the distal tip of the tube. When inflated, it seals the trachea to prevent air leaks and protect against aspiration. The uncuffed version is suitable for children aged 5 and below or for cases where the inner diameter of the tube is less than 5.5mm. The following is an illustrative image of cuffed and uncuffed endotracheal tubes.

Cuffed and uncuffed endotracheal tubes from Bever Medical Devices 

3) Murphy Eye is a side hole near the distal end to ensure airflow even if the main opening is blocked.

The standard endotracheal tube has the following applications.

1) When a patient is under anesthesia, the use of the tube provides a secure airway during surgical procedures.

2) It can be used in critical situations such as respiratory failure or cardiac arrest, to provide an open airway.

3) It can be connected to a ventilator to support breathing in intensive care units.

Concluding comments

Each endotracheal tube type offers unique features to meet specific clinical needs. Healthcare providers choose the appropriate endotracheal tube type for individual patient situations to maintain safe and effective airway patency. 

There are other medical devices designed for airway patency purposes too, for example, nasopharyngeal airways. When you are considering the kind of products that are used for airway patency management you can think of endotracheal tubes and nasopharyngeal airways. The nasopharyngeal airway is a flexible tube typically made of soft plastic or rubber. It is inserted through a nostril and extends into the nasopharynx. It is useful in cases where the tongue or soft tissues obstruct the pharynx. The following image shows a typical nasopharyngeal airway.

Nasopharyngeal airway from Bever Medical Devices.