Endotracheal intubation is a life-saving medical procedure, not a disease, that involves placing a breathing tube through the mouth or nose into the windpipe to help someone breathe when they cannot do so on their own.

Introduction: Who Needs Intubation and When to Seek Help

Endotracheal intubation is not something that patients seek out like a regular diagnostic test. Instead, it is an emergency procedure performed when a person cannot maintain their own airway or breathe without assistance. Understanding when this procedure becomes necessary can help family members recognize serious situations that require immediate medical attention.^[1]

A person should receive immediate emergency care if they show signs of severe breathing difficulty, loss of consciousness, or inability to protect their airway. These situations most commonly arise in emergency departments, operating rooms, or intensive care units. Emergency medical services personnel may also perform intubation outside hospital settings when someone’s life is in immediate danger.^[1]

Several specific conditions typically lead to the need for intubation. When someone suffers an injury or trauma to their abdomen, chest, or neck that affects their airways, healthcare providers must act quickly to secure the airway. Similarly, people who have lost consciousness or have a very low level of consciousness may lose control of their airway, meaning they can no longer keep it open or prevent substances like saliva or vomit from entering their lungs.^[1]

Respiratory failure, which means the lungs are not working well enough to provide oxygen to the body or remove carbon dioxide, is another common reason for intubation. This can happen due to severe pneumonia, emphysema, heart failure, or a collapsed lung. When something becomes caught in the airway and blocks the flow of air, immediate intubation may be the only way to restore breathing.^[3]

People undergoing surgery that requires general anesthesia, a state of controlled unconsciousness, will need intubation because the anesthesia makes them unable to breathe on their own. The procedure is also necessary when someone experiences sudden loss of heart function, known as cardiac arrest, or a temporary stop in breathing called apnea.^[1]

Intubation is also performed to protect the lungs in people who cannot protect their own airway and are at risk for breathing in fluid, food, or other substances. This includes people who have suffered certain types of strokes, drug overdoses, or massive bleeding from the stomach or throat. The breathing tube acts as a barrier that prevents these dangerous materials from entering the lungs.^[3]

How Healthcare Providers Determine When Intubation Is Needed

Before performing intubation, healthcare providers must carefully evaluate the patient’s condition. This assessment happens very quickly in emergency situations but follows a systematic approach to ensure the procedure is both necessary and likely to be successful.^[2]

Medical professionals look for specific signs that indicate a patient needs help with breathing. These include altered mental status, poor ventilation, and poor oxygenation. When someone has an altered mental status, they may be confused, unresponsive, or unable to follow commands. This condition makes it difficult for them to maintain their own airway because the muscles that normally keep the airway open may relax too much.^[2]

Poor ventilation means the person is not moving air in and out of their lungs effectively. Healthcare providers can tell this is happening by watching how hard someone is working to breathe, listening to breath sounds with a stethoscope, and measuring carbon dioxide levels in the blood. When carbon dioxide builds up because the person cannot breathe it out, the blood becomes too acidic, a dangerous condition that can damage organs.^[10]

Poor oxygenation occurs when the blood does not contain enough oxygen, even when the person is breathing 100% oxygen through a mask. Healthcare providers measure oxygen levels using a small device called a pulse oximeter that clips onto a finger. When oxygen levels remain dangerously low despite giving extra oxygen, intubation and mechanical ventilation may be the only way to save the person’s life.^[10]

The evaluation also includes examining the patient’s physical characteristics that might make intubation more difficult. Providers check whether the person can open their mouth wide, whether they have a thick neck, whether they have loose or broken teeth, and whether they can extend their neck backward. All of these factors affect how easily the provider can see the vocal cords and place the tube. A very obese person, someone who snores heavily, or someone with a very short, thick neck may present more challenges during intubation.^[19]

When there is time to review medical history, providers ask about previous surgeries, especially any previous intubations. If someone has been intubated before, medical records can show whether it was difficult and what techniques worked. They also ask about conditions like sleep apnea, which often indicates a difficult airway, and any previous throat or neck surgeries that might have changed the anatomy of the airway.^[19]

The Intubation Procedure: Step by Step

Intubation is a carefully choreographed procedure that, in the hands of an experienced provider, can be completed in less than a minute during an emergency. However, even though it can be done quickly, each step must be performed correctly to ensure success and safety.^[1]

The first critical step is preoxygenation, which means giving the patient extra oxygen before the procedure begins. This step is extremely important because once the provider begins intubation, the patient will stop breathing for a short time. By filling the lungs with as much oxygen as possible beforehand, the patient has a reserve supply that continues to move from the lungs into the bloodstream even while they are not breathing. This oxygen reservoir can prevent dangerous drops in oxygen levels for several minutes in a healthy adult, though the time is much shorter in children, very obese people, or those with lung disease.^[12]

Next, the patient receives medications through an intravenous line, a small tube placed in a vein in the arm. These medications serve several purposes. First, they make the patient fall asleep so they do not feel pain or remember the procedure. Second, they relax the muscles, including those in the throat, which makes it easier to place the tube. The combination of a sedative and a muscle relaxant is called rapid sequence intubation when performed quickly in an emergency.^[10]

Once the patient is asleep and relaxed, the healthcare provider positions the patient’s head and neck to create the straightest possible path from the mouth to the windpipe. This usually involves tilting the head back and lifting it slightly above the level of the bed, a position called the “sniffing position” because it looks like someone sniffing the air. In very obese patients, providers may need to place pillows or blankets under the shoulders and head to achieve proper positioning.^[17]

The provider then inserts an instrument called a laryngoscope into the patient’s mouth. This device has a handle, lights, and a curved or straight blade. The blade is carefully advanced along the tongue toward the back of the throat, pushing the tongue out of the way. The provider must avoid the teeth, as hitting them can cause damage or even knock them out. The blade lifts the soft tissue at the base of the tongue to expose the epiglottis, a flap of tissue that normally protects the larynx, also called the voice box.^[1]

With the epiglottis lifted out of the way, the provider can see the vocal cords, two bands of tissue that open and close across the entrance to the trachea or windpipe. The breathing tube must pass between these vocal cords to enter the trachea correctly. If the tube accidentally goes into the esophagus, the tube that leads to the stomach instead of the lungs, no air will reach the lungs and the patient will not receive oxygen.^[2]

The provider advances the tip of the laryngoscope blade into the larynx and then into the trachea, visualizing the path for the breathing tube. The endotracheal tube, a flexible plastic tube that has been pre-lubricated to help it slide more easily, is then passed through the mouth, past the vocal cords, and into the trachea. The tube is advanced until it sits just above the point where the trachea divides into the right and left main airways that lead to each lung.^[1]

Once the tube reaches the correct depth, a small balloon or cuff around the outside of the tube is inflated with air. This cuff serves multiple purposes: it keeps the tube from moving out of place, it prevents air from leaking around the tube, and it protects the lungs by blocking stomach contents or other materials from traveling down the trachea past the tube. After the cuff is inflated, the laryngoscope is removed.^[6]

The tube is then secured in place using tape on the sides of the mouth or a strap around the head. This prevents the tube from being accidentally pulled out during patient movement or while connecting it to a ventilator or breathing bag. Throughout the entire procedure, providers work carefully but efficiently, knowing that speed is important but accuracy is essential.^[1]

Confirming Correct Tube Placement

Placing the tube correctly is only half the job. Healthcare providers must confirm that the tube is actually in the trachea and not in the esophagus, and that it is at the right depth. This confirmation step is absolutely critical because if the tube is in the wrong place, the patient will not receive oxygen and could die within minutes.^[19]

The first method of confirmation happens immediately. The provider watches to see if the chest rises and falls equally on both sides when air is pushed through the tube using a hand-held bag. They also listen with a stethoscope over the stomach and over both sides of the chest. If the tube is correctly placed in the trachea, they should hear breath sounds over the lungs but not over the stomach. If they hear gurgling sounds over the stomach, the tube may be in the esophagus and must be removed and replaced.^[1]

Many providers also use a device that measures carbon dioxide in the air coming out of the tube. The human body continuously produces carbon dioxide, which is carried by the blood to the lungs and breathed out. If the tube is in the trachea, each breath out will contain carbon dioxide. If the tube is in the esophagus, there will be little or no carbon dioxide because the stomach does not produce or release carbon dioxide in the same way.^[19]

While these immediate checks are very reliable, the definitive confirmation comes from a chest X-ray. The X-ray shows the exact position of the tube and confirms that it is in the trachea at the correct depth. The tip of the tube should sit several centimeters above where the trachea splits into the right and left main bronchi. If the tube has been advanced too far, it usually goes into the right main bronchus because of the angle at which it branches off. When this happens, only the right lung receives air and the left lung collapses, a situation that must be corrected immediately by pulling the tube back slightly.^[2]

Equipment Used in Intubation

The success of intubation depends not only on the skill of the provider but also on having the right equipment readily available. Each piece of equipment serves a specific purpose in making the procedure safe and effective.^[2]

The laryngoscope is the primary tool for visualizing the vocal cords. Traditional laryngoscopes come in two main types: curved blades, called Macintosh blades, and straight blades, called Miller blades. Curved blades are designed to lift the tongue and soft tissues by pressing into a small pocket at the base of the tongue, which indirectly lifts the epiglottis. Straight blades actually lift the epiglottis directly. Many providers prefer curved blades because they are more forgiving if the blade is not positioned perfectly, while others prefer straight blades for certain situations, particularly in infants and children.^[17]

In recent years, video laryngoscopes have become increasingly popular. These devices have a small camera at the tip of the blade that displays the view of the vocal cords on a screen. This technology offers several advantages: the provider does not need to position their eye directly over the patient’s mouth, other team members can see exactly what the provider sees, and the camera can sometimes provide a better view in patients with difficult anatomy. However, traditional direct laryngoscopy remains an essential skill because video equipment can malfunction or may not be available in all settings.^[2]

A bougie, also called a tracheal tube introducer, is a semi-rigid plastic guide that can be used when the vocal cords are difficult to see. The provider slides this thin, flexible device through the vocal cords first, then threads the endotracheal tube over it like a bead on a string. Once the tube is in the correct position, the bougie is removed. This technique has helped many providers successfully intubate patients when standard techniques were failing.^[16]

Endotracheal tubes come in different sizes to accommodate patients of different ages and sizes. The size is measured by the internal diameter of the tube in millimeters. Adult men typically receive a tube that is 8 to 9 millimeters in diameter, while adult women typically receive a 7 to 8 millimeter tube. Children require much smaller tubes, and selecting the right size for a child involves using age-based formulas or referring to standardized charts. Using a tube that is too large can cause damage to the vocal cords and trachea, while a tube that is too small may not provide adequate ventilation or may allow leakage of air around it.^[6]

Other essential equipment includes suction devices to remove secretions, blood, or vomit from the mouth and throat that could block the view or be pushed into the lungs; oxygen sources to provide preoxygenation and post-intubation ventilation; monitoring equipment to measure oxygen levels and carbon dioxide; and emergency medications to treat complications if they occur.^[2]

Special Circumstances in Intubation

While the basic principles of intubation remain the same, certain situations require modifications to the standard technique. Understanding these special circumstances helps healthcare providers adapt their approach to maximize safety and success.^[6]

Children and newborn infants present unique challenges for intubation. Their airways are proportionally smaller, their tongues are larger relative to their mouth size, and their larynx sits higher in the neck and at a more forward angle compared to adults. Young children also have much shorter times before their oxygen levels drop dangerously low once they stop breathing, sometimes less than a minute in newborns. For these reasons, pediatric intubation requires specialized training and equipment, including smaller tubes, smaller laryngoscope blades, and different medication doses calculated based on the child’s weight.^[6]

Patients with suspected spine or neck injuries require special precautions during intubation. Normally, tilting the head back helps align the airway for the best view of the vocal cords. However, in someone who might have broken bones or damaged ligaments in their neck, moving the neck could cause permanent paralysis by injuring the spinal cord. In these cases, providers must keep the neck as still as possible while still achieving successful intubation. This often requires additional personnel to hold the head stable, modified positioning techniques, or the use of video laryngoscopy or other advanced methods.^[6]

When intubation through the mouth proves impossible, alternative surgical airways may be necessary. The most common surgical airway is called a cricothyrotomy, which involves making a cut through the skin and a membrane in the front of the neck to reach the trachea below the level of the vocal cords. This procedure is reserved for true emergencies when the patient cannot breathe and cannot be intubated by any other method. It is performed only when the patient will die without it, as it carries significant risks including bleeding, damage to surrounding structures, and infection.^[2]

Some patients require intubation through the nose instead of the mouth, a technique called nasotracheal intubation. This approach may be chosen when the patient has severe injuries to the mouth or jaw that make oral intubation impossible, or when the patient needs to remain intubated for an extended period and nasal intubation is more comfortable. The tube is passed through one nostril, through the back of the nose and throat, and down into the trachea. This technique requires special skill and carries different risks, including nosebleeds and injury to the nasal passages.^[6]

Patients who are awake but need intubation present another challenging scenario. In some situations, it may be too dangerous to give the sedating medications normally used for intubation, perhaps because the patient’s blood pressure is already very low or because the provider is concerned that sedation will make the situation worse. In these cases, the provider may perform an “awake intubation” using only local anesthetics sprayed or injected into the throat to numb the area. This technique requires excellent communication with the patient, who must remain as calm and cooperative as possible during what is understandably a frightening experience.^[6]

Risks and Complications of Intubation

Like any medical procedure, intubation carries risks. While serious complications are rare, understanding these risks helps patients and families make informed decisions and helps providers take steps to minimize them.^[3]

The most common minor problems after intubation include a sore throat, hoarseness, and tooth damage. The sore throat results from irritation of the tissues in the throat and typically resolves within a few days. Hoarseness occurs when the tube passes through the vocal cords and may last several days to a week. Tooth damage, while relatively rare, can happen if the laryngoscope blade strikes the teeth during the procedure, particularly the front teeth. Loose or damaged teeth are at higher risk, which is why providers examine the teeth carefully before intubation.^[3]

Bleeding can occur from trauma to the tissues of the mouth, throat, or nose. Usually this bleeding is minor and stops on its own, but in rare cases it can be significant enough to require intervention. The risk is higher in patients who have bleeding disorders or who take blood-thinning medications.^[11]

More serious complications include trauma to the larynx, the delicate cartilage structures that make up the voice box, or to the trachea itself. Rough or forceful placement of the tube can cause tears or bruising of these tissues. Injury to the thyroid gland, which sits just in front of the trachea in the lower neck, is also possible though uncommon. The esophagus, which runs behind the trachea, can potentially be punctured, though this is extremely rare.^[11]

Perhaps the most serious complication is failure to successfully place the tube in the trachea, or accidental placement in the esophagus that goes unrecognized. When this happens, the patient receives no oxygen and can suffer brain damage or death within minutes. This is why confirmation of correct tube placement is so critical and why providers use multiple methods to verify placement.^[19]

Sometimes the tube may be placed correctly but advanced too far, entering one of the main bronchi instead of remaining in the trachea above where it splits. When this happens, only one lung receives ventilation while the other collapses. This situation must be recognized and corrected quickly to prevent oxygen levels from dropping and to prevent damage to the lung that is not being ventilated.^[2]

Infection is always a concern with any invasive procedure. The tube itself can serve as a pathway for bacteria to enter the lungs, potentially causing pneumonia. The risk of infection increases the longer the tube remains in place. Healthcare providers take strict precautions to keep everything as clean as possible and to remove the tube as soon as it is safe to do so.^[11]

In rare cases, the procedure of intubating someone can cause their body to develop abnormal heart rhythms or their blood pressure to change dramatically. The act of placing the laryngoscope blade and lifting the tongue activates certain nerves that can affect heart rate and blood pressure. Most people tolerate these changes without problems, but in patients who already have heart disease or who are critically ill, these changes can be dangerous. Providers give medications before intubation to help minimize these effects.^[2]

After Intubation: Monitoring and Care

Once the tube is successfully placed and confirmed to be in the correct position, the patient requires continuous monitoring and specialized care. The breathing tube represents a major change in how the body functions, and healthcare providers must manage many aspects of the patient’s condition to ensure safety and comfort.^[1]

The patient will be in a hospital setting where their breathing and blood oxygen levels can be monitored constantly. If they needed intubation because of an illness or injury, they will be monitored in an intensive care unit. If they were intubated for surgery, they may have the tube removed in the operating room or recovery area once they wake up from anesthesia and can breathe on their own.^[3]

The tube is usually connected to a mechanical ventilator, a machine that helps push air into the lungs. The ventilator can be adjusted to provide exactly the amount and type of breathing support that the patient needs. Some patients need complete support, with the machine doing all the breathing for them. Others need only partial support, with the machine helping but the patient doing some of the work of breathing themselves.^[1]

Patients who are awake while intubated often find the experience very uncomfortable and frightening. The tube prevents them from speaking because it passes through the vocal cords, taking away their ability to communicate verbally. They also cannot swallow normally, so they cannot eat or drink anything by mouth. Healthcare providers give medications to reduce anxiety and discomfort, and they provide other methods of nutrition, either through an intravenous line or through a separate feeding tube that goes into the stomach.^[1]

The tube must be kept clean and properly positioned at all times. Healthcare providers regularly suction secretions from the tube to prevent them from blocking it or becoming infected. They check the position of the tube periodically with X-rays to make sure it has not moved. They also adjust the cuff pressure to ensure it is inflated enough to protect the airway but not so tight that it damages the trachea.^[3]

Removing the Breathing Tube

When the patient no longer needs help with breathing, the tube can be removed, a process called extubation. Deciding when to remove the tube is just as important as deciding when to place it. Remove it too soon, and the patient may need to be intubated again. Wait too long, and the patient faces unnecessary risks from having the tube in place.^[6]

Before removing the tube, healthcare providers perform several assessments. They want to see that the patient is alert enough to protect their own airway, that they can breathe adequately on their own with minimal or no support from the ventilator, that their oxygen levels remain good, and that the original problem requiring intubation has improved. They may perform a trial where they turn down the ventilator support to see how well the patient breathes independently while still having the safety of the tube in place.^[6]

The actual removal of the tube is relatively quick. The provider deflates the cuff around the tube, asks the patient to take a deep breath, and then quickly pulls the tube out while the patient exhales. The patient is then given supplemental oxygen through a mask or nasal cannula. Healthcare providers watch closely for the first several hours after extubation to make sure the patient continues to breathe well and does not develop swelling in the airway that could cause problems.^[6]

Most patients recover fully from intubation without long-term effects. The sore throat and hoarseness typically resolve within a few days to a week. Patients who were intubated for extended periods, sometimes weeks or longer, may have more lasting effects including weakness, difficulty swallowing, or voice changes. These patients often benefit from rehabilitation and therapy to help them regain their strength and function.^[3]