What Is an Endotracheal Tube? Uses, Parts & Size Guide

An endotracheal tube, often shortened to ET tube, is a flexible medical device inserted into a patient's windpipe to keep the airway open and allow air to move freely into the lungs. It is one of the most widely used tools in operating rooms, intensive care units, and emergency departments around the world. Whether a patient needs help breathing during surgery, is struggling with respiratory failure, or requires resuscitation after cardiac arrest, an endotracheal tube often plays a central role in keeping them stable. This guide walks through what the device is used for, its parts, common sizes, the different types available, how it is inserted, its benefits, and how it is cared for once placed.

What Is an Endotracheal Tube Used For?

Endotracheal tubes serve several critical purposes in modern medicine, all centered on securing and protecting a patient's airway.

General Anesthesia

During many surgical procedures, patients are placed under general anesthesia, which relaxes the muscles and suppresses natural breathing reflexes. An endotracheal tube keeps the airway open and connects the patient to a ventilator, allowing the anesthesia team to control breathing throughout the operation.

Mechanical Ventilation

Patients who cannot breathe adequately on their own, whether due to illness, injury, or sedation, often need mechanical ventilation. The tube acts as a direct pathway between the ventilator and the lungs, ensuring a steady and controlled supply of oxygen.

Emergency Airway Management

In emergencies where a patient's airway is blocked, swollen, or at risk of collapsing, intubation with an endotracheal tube provides an immediate and reliable way to maintain airflow until the underlying problem is addressed.

Respiratory Failure

Conditions such as severe pneumonia, acute respiratory distress syndrome, or chronic lung disease can push the lungs past their ability to function independently. An ET tube supports oxygen delivery and carbon dioxide removal when the body can no longer manage this on its own.

Trauma and Critical Care

Patients with serious injuries, particularly those affecting the head, chest, or neck, may lose the ability to protect their own airway. Intubation prevents choking, aspiration, and further complications while the patient is stabilized and treated.

Cardiopulmonary Resuscitation (CPR)

During cardiac arrest, securing the airway with an endotracheal tube allows rescue teams to deliver consistent, effective breaths alongside chest compressions, improving the chances of a successful resuscitation.

Parts of an Endotracheal Tube

An endotracheal tube may look simple, but it is made up of several functional components. The main body is a flexible tube, usually made of medical-grade PVC or silicone, marked with depth indicators so clinicians know exactly how far it has been inserted. At the tip is either a cuffed or uncuffed end; cuffed tubes have an inflatable balloon that seals the airway and prevents air leakage or fluid aspiration. The cuff is inflated through a small pilot balloon and valve located outside the patient's mouth, which lets clinicians monitor and adjust cuff pressure. A standard 15mm connector sits at the opposite end, allowing the tube to attach to a ventilator or manual resuscitation bag. Many tubes also include a Murphy eye, a small side hole near the tip that provides an alternate air pathway if the main opening becomes blocked.

Endotracheal Tube Sizes

Endotracheal tubes are sized according to their internal diameter, measured in millimeters, and selecting the right size is essential for both effective ventilation and patient safety. Adult tubes typically range from about 7.0mm to 9.0mm, with women generally requiring slightly smaller sizes than men. Pediatric sizing is more precise and often calculated using a patient's age or a formula based on age divided by four plus four, since children's airways vary significantly with growth. Premature infants and newborns may need tubes as small as 2.5mm to 3.5mm. Clinicians also consider tube length markings, which help confirm correct placement above the carina, the point where the trachea splits into the two main bronchi.

Types of Endotracheal Tubes

Not all endotracheal tubes are built the same way, and the right choice depends on the clinical situation, procedure type, and patient anatomy.

Cuffed Endotracheal Tube

These tubes have an inflatable cuff near the tip that creates a seal against the tracheal wall. This seal helps prevent air leakage during ventilation and reduces the risk of fluid or secretions entering the lungs, making cuffed tubes the standard choice for most adult patients.

Uncuffed Endotracheal Tube

Without an inflatable cuff, these tubes rely on a close anatomical fit to maintain a seal. They are commonly used in young children, whose narrower airways naturally form a tighter fit, reducing the risk of pressure-related tracheal injury.

Reinforced (Flexometallic) ET Tube

Built with a spiral wire embedded in the tube wall, reinforced tubes resist kinking or collapsing, even when the patient's head or neck is repositioned. They are frequently used in surgeries involving the head, neck, or spine, where flexibility and positioning matter.

Oral Endotracheal Tube

Inserted through the mouth, oral tubes are the most common choice for emergency intubation and general anesthesia because they are quicker and generally easier to place than nasal tubes.

Nasal Endotracheal Tube

Passed through the nose and down into the trachea, nasal tubes are often used for certain oral or dental surgeries, or in situations where a patient needs longer-term ventilation and better tube stability.

Preformed (RAE) Endotracheal Tube

Shaped with a pre-set bend, RAE tubes direct the tube and its connector away from the surgical field, making them especially useful during procedures involving the face, mouth, or airway itself.

How Is an Endotracheal Tube Inserted?

Placing an endotracheal tube, a process called intubation, typically begins with the patient positioned to align the mouth, throat, and airway. A clinician uses a laryngoscope to visualize the vocal cords, then gently guides the tube through the mouth or nose, past the vocal cords, and into the trachea. Once positioned correctly, the cuff, if present, is inflated to secure the seal. Proper placement is then confirmed through several methods, including listening for equal breath sounds on both sides of the chest, observing chest rise, and using capnography to detect carbon dioxide in exhaled air. The tube is then secured in place with tape or a specialized holder to prevent accidental movement or displacement.

Advantages of Endotracheal Tubes

Endotracheal tubes offer several important benefits in patient care. They provide a secure and reliable airway, reducing the risk of obstruction or collapse. They allow precise control over ventilation, which is critical during surgery and in intensive care settings. Cuffed tubes also help protect the lungs from aspiration of stomach contents, blood, or secretions, lowering the risk of complications like aspiration pneumonia. Additionally, they allow for direct suctioning of the airway when needed and provide a dependable route for delivering oxygen and anesthetic gases consistently throughout a procedure or treatment period.

Popular Endotracheal Tube Products Available at SurgiNatal

Polymed Endotracheal Tube Cuffed: Features a high-volume, low-pressure cuff to ensure effective tracheal sealing while minimizing mucosal damage. 

Romsons Endotracheal Tube Plain: A cuffless tube ideal for pediatric use, designed to prevent airway trauma in smaller patients. 

Sterimed Endotracheal Cuffed Reinforced Tubes: Built with wire reinforcement to prevent kinking, maintaining a secure airway during difficult positioning.

Rusch Flexometallic ET Tube: A highly flexible, spiral-reinforced tube designed to resist collapse and kinking during complex surgical procedures.

Portex Helmier Endotracheal Tube Cuffed: 

A premium cuffed tube offering precise placement, reliable ventilation, and excellent patient comfort. 

Final Thought

The endotracheal tube remains one of the most essential devices in modern airway management, providing life-saving respiratory support during surgery, critical illness, trauma, and emergency resuscitation. Understanding its uses, parts, sizing, and types enables healthcare professionals to make informed clinical decisions and deliver safe patient care. At SurgiNatal, we are committed to supplying high-quality airway management products, including reliable endotracheal tubes, to support healthcare providers in delivering effective respiratory care across hospitals, clinics, and emergency settings.