What is Post-Intubation Laryngeal Edema?
Injuries to the voice box, or larynx, are common after a medical procedure called endotracheal intubation, where a tube is inserted through the mouth or nose into the windpipe to help the patient breathe. These injuries can show up as swelling, ulcers, abnormal growths, and problems with vocal cord movement, often leading to a narrowing of the airway. Of these injuries, swelling of the larynx, or laryngeal edema, is a common complication that can result from the pressure and inflammation caused by the tube rubbing against the larynx.
However, even though almost half of the patients who have been intubated might experience laryngeal edema, most of them do not show symptoms or only exhibit mild symptoms. Despite this, laryngeal edema is a common cause of difficulty in breathing and/or a high-pitched noise when exhaling, following the removal of the tube. This can sometimes result in failure to remove the tube and the need to reinsert it. It’s important to note that having to reinsert the tube is linked to increased health risks and the risk of death, making laryngeal edema a critical issue. It’s crucial to prevent and manage this condition properly.
A better term for this condition could be post-intubation laryngeal edema, as the swelling starts to develop soon after the tube is inserted, although it only becomes noticeable after the tube is removed. It’s extremely important to identify and manage, laryngeal edema before attempting to remove the breathing tube from a patient, as having to reinsert the tube can increase the risks to the patient’s health and life.
This text talks about the causes, occurrence rates, clinical evaluation, and management of laryngeal edema following intubation, emphasizing the need to identify high-risk patients and act quickly with prevention and treatment strategies. It also mentions the importance of teamwork and communication among healthcare professionals in improving patient outcomes.
What Causes Post-Intubation Laryngeal Edema?
When you get a tube put down your throat, or what we call endotracheal intubation, it can make the areas it touches inflamed. This might explain how throat swelling or laryngeal edema can happen. If a tube stays in your throat for a long time, it may cause inflammation, swelling, ulcers, especially affecting your vocal cords and the areas where the tube’s cuff touches.
Past research involving 700 patients who needed tubes in their throats and help with breathing showed that people who spent over 36 hours on a ventilator and women were more likely to have laryngeal edema after the tube was taken out.
Another study with 761 ICU patients found that people who had injuries when they were admitted, women, people who’d been intubated for less than a week, people with a smaller ratio between their height and their tube’s diameter, and people not pre-treated with a drug called methylprednisolone were more at risk of developing laryngeal edema after the tube was taken out.
The risk also goes up for people who had surgery on the head and neck, those who are head down or face down during brain surgery, pregnant women, those who received a lot of fluids, those with injuries to the neck and airway, inhalation injuries and burns, those who had a tough time being intubated, and those who took the tube out themselves.
People who had surgery to remove both sides of the neck lymph nodes and later had a procedure related to the urinary tract were seen to have severe laryngeal edema and had to get a tracheostomy, which is a hole made in the neck for breathing. In these cases, the risk may be higher due to the cutting of lymph drainage routes or swollen veins in the neck. It’s also thought that acid reflux could contribute to laryngeal edema after the tube is taken out.
In simple terms, the risk for throat swelling after putting a tube in can be put into three groups: factors related to the intubation process, factors that happen after intubation, and personal factors.
For putting the tube in, some risk factors include:
* A tough time getting intubated
* A larger tube size (small height-to-tube diameter ratio)
For after putting the tube in, some risk factors include:
* Keeping the tube in the throat for a long time
* High tube cuff pressures
* Being unsettled while the tube is in
* Taking the tube out and putting it back in yourself
For other factors related to the patient, situation or surgery, some risk factors include:
* The kind of surgery (e.g., head and neck surgery)
* Being face down during brain surgery
* Pregnancy
* Getting a lot of fluids
* Injuries to the neck and airway
* Inhaling injuries and burns
* A lower Glasgow Coma Scale score
* Not receiving sedation
* Being a woman
* Higher body mass index (>26.5)
* Acid reflux
Risk Factors and Frequency for Post-Intubation Laryngeal Edema
Post-intubation laryngeal edema, or swelling in the throat after having a tube placed to help with breathing, is difficult to measure. This is due to differences in definitions, criteria for diagnosis, and detection methods. These variations are made even more complex by the different populations studied and the use of different materials for the breathing tube.
- Studies show that the occurrence of throat swelling after tube removal ranges from 5% to 54%.
- The reported occurrence of harsh, noisy breathing after tube removal varies between 1.5% and 26.3%.
- Up to 10.5% of patients with throat swelling will struggle with removing the tube and will need it reinserted.
- The overall occurrence of failed tube removal requiring tube reinsertion varies from 1.8% to 31.4%.
These differences in numbers are likely due to the different methods and definitions used in these studies.
Research also provides us some other interesting details. For instance, it has been seen that throat swelling is more common in women. A study conducted in France involving 136 patients who had a breathing tube observed throat injuries in 73% of the patients; throat swelling was seen even more commonly, occurring in 54.4% of the patients. Harsh, noisy breathing was present in 13% of the patients. Nearly two-thirds of the patients with harsh, noisy breathing had throat swelling and decreased vocal cord movement. Only half of the patients with this type of noisy breathing ended up needing the tube reinserted, and only half of those who needed reinsertion had noisy breathing. Earlier studies also noted a number of patients with varying degrees of swelling and sores in the throat.
Signs and Symptoms of Post-Intubation Laryngeal Edema
Swelling of the voice box, or laryngeal edema, is a common injury seen after a tube has been placed in the patient’s airway for breathing or medication administration, known as intubation. Most of the time, this swelling doesn’t lead to serious symptoms – it might cause a mild sore throat, issues with speaking, or difficulty in swallowing. But in severe cases, this can lead to a harsh, high-pitched breathing sound, known as stridor, which can result in the patient needing to be re-intubated. Stridor may become worse if there’s also swelling of the vocal cords, restricting their movement.
Typically, this swelling happens within 24 hours of the tube being placed, and symptoms become noticeable as soon as the tube is removed, but there have been cases where symptoms took up to 48 hours to appear after the tube was removed after surgery. Usually, the inflammation and swelling of the voice box subside within a day or two after removal of the tube. If symptoms persist beyond this time, it may indicate other injuries caused by the tube placement, such as internal bleeding, cuts, or torn tissues.
Further problems that may occur due to the tube being in place for a long period of time, such as sores, lumps of tissue known as granulomas, scar tissue, and muscle paralysis, should also be considered. It’s also worth noting that a substantial number of patients need to be re-intubated within the first 24 hours after the tube has been removed, and occasionally this can happen up to 72 hours later.
Testing for Post-Intubation Laryngeal Edema
Laryngeal edema, or swelling in the larynx (voice box), can sometimes develop following the use of a breathing tube (intubation). Mostly, this swelling doesn’t cause much trouble. However, in some cases, it might lead to difficulty breathing, a condition known as post-extubation stridor, and require the breathing tube to be reinserted. Several tests have been developed to check for swelling in the airway before the breathing tube is removed (extubation). These tests include the cuff leak test, ultrasound, and video laryngoscopy.
The cuff leak test is a simple, non-invasive exam that helps doctors determine the risk for laryngeal edema and post-extubation stridor in patients with breathing tubes. The test gives an idea of the space available between the voice box and the breathing tube. A smaller or absent “cuff leak” could mean different issues such as swelling, secretions, or narrowing in the airway. The test can be done by listening for an audible leak when the cuff is deflated or by calculating the difference in volume of air inhaled and exhaled over a few breaths. A cuff leak test predicts risk for breathing problems after the breathing tube is removed with varying degrees of accuracy. However, most studies find that it is usually more than 90% accurate.
Ultrasound of the voice box is another method used to predict risk of breathing difficulties after extubation. It measures the width of the air column at the level of the vocal cords before and after deflating the cuff. Promising results have been seen in a few small studies, but larger studies are needed to understand the usefulness of this method fully.
Lastly, video laryngoscopy, an examination that makes use of a small camera to visualize the voice box and nearby structures, might also be helpful. This technique can distinguish between structural problems like swelling, or functional problems like muscle spasms in the larynx. However, more studies are needed to understand the value of video laryngoscopy in predicting post-extubation stridor.
Treatment Options for Post-Intubation Laryngeal Edema
Several studies have looked into the use of steroids as a preventive measure to avoid issues with breathing (known as post-extubation stridor) after a breathing tube has been removed. Generally, these studies have found positive outcomes although not in every individual case. In particular, giving a single dose of steroids to patients without specifically choosing those at high risk of post-extubation problems, did not show any benefits. Therefore, many health experts recommend using a specific type of steroid – methylprednisolone – before removing the breathing tube based on the successful methods used in these studies.
When it comes to the benefits of using a medication (commonly known as adrenaline) to help manage breathing issues after the removal of a breathing tube, there’s not a lot of evidence for its effectiveness in adults, although it has been used in children suffering from a specific breathing disorder known as croup. Nevertheless, a 1995 study reported that four adult patients with different causes of upper airway issues were successfully treated with adrenaline nebulization.
One study that tried to combine the use of steroids and adrenaline nebulization to prevent worsening of airway blockage due to swelling in the throat in newborns and children did not find this combination beneficial. However, a recent study suggested that another medication – budesonide nebulization – might be a possible alternative for a type of steroid – IV dexamethasone – in improving the amount of air leak volume in patients with a breathing tube.
Heliox, a mixture of helium and oxygen, has been shown to reduce post-extubation breathing issues in children who have undergone trauma, by reducing the amount of effort required for breathing. However, this effect seems to only buy time before a more definite intervention is done to unblock the airway. The effectiveness of Heliox on adult patients remains to be seen.
For practical purposes, all patients at a high risk for swelling in the throat or breathing issues after tube removal should undergo a bedside test known as cuff leak test. If this test shows a negative result (i.e., less or no air leaking past the tube), these patients should receive a dose of IV methylprednisolone at least 4 hours before the tube is removed. These extubations need to be closely monitored, and routine plans should be carried out appropriately.
In cases where patients continue to have symptoms despite treatment (like steroids or adrenaline nebulization), they are monitored for an hour before deciding to reintubate. If the patient’s condition is improving slowly within this one-hour period, the treatments are continued for 24 to 48 hours before reassessing.
Finally, a study on the use of non-invasive ventilation (NIV) in patients with respiratory failure after extubation found increased death rates likely due to delayed reintubation. Based on these findings, the European Respiratory Society/ATS guidelines recommend against the use of NIV in cases of respiratory failure after extubation.
What else can Post-Intubation Laryngeal Edema be?
Some conditions have symptoms similar to other illnesses and could potentially be confused with them. These include:
- Post-extubation stridor: a condition where there’s a narrowing of the throat or windpipe after a tube used to help with breathing is removed, creating a unique inspiratory crowing sound
- Laryngospasm: a sudden clenching of the vocal cords caused by a stimulation of the superior laryngeal nerve. This often occurs in patients who are not well-awake enough to resist the cloistering reflexes due to irritating events like the removal of the breathing tube, pooling of secretions, blood, or a foreign object in the airway.
- Angioedema or Anaphylaxis: swelling caused by various drugs, which can also cause breathing problems. Anaphylaxis is treated with adrenaline injection.
- Foreign body in the airway: any object that accidentally gets into the airways causing an obstruction.
- Post-surgical hematomas causing airway compression: a collection of blood outside of the blood vessels caused by surgery, which can compress the airway.
- Vocal cord palsies following neck surgeries: a condition where the vocal cord becomes weak or immobile after a neck surgery.
- Sleep apnoeas: a potentially serious sleep disorder where breathing repeatedly stops and starts.
Stridor after extubation can be due to severe laryngeal edema. This condition could lead to a situation where nearly half of the affected individuals may need to be reintubated. Similarly, severe bronchospasm, and pulmonary edema can sometimes mimic laryngeal edema. In rare cases, stridor after extubation could cause negative pressure pulmonary edema. Treatment generally involves removing the cause of the condition and applying positive pressure if necessary.
What to expect with Post-Intubation Laryngeal Edema
Most of the time, swelling in your throat from a tube inserted during surgery (also known as post-intubation laryngeal edema) doesn’t cause symptoms and doesn’t require treatment. The severity of this swelling and possible related injuries can vary widely from patient to patient. Different studies have found that between 5 to 54% of patients experience this swelling after the tube is removed. Of these patients, only about 10.5% will need the tube inserted again. It’s important to know that every time the tube needs to be put back in, it increases the risk of complications and even death.
Swelling that blocks the vocal cords’ fluid movement led to noisy breathing after tube removal in nearly two-thirds of the cases in a study of 136 patients. The risk for noisy breathing after tube removal is typically evaluated with a bedside test called a CLT. This test is done on patients who are at high risk, including those who had a difficult tube insertion, who had a tube in place for more than six days, those with a heavy tube, women, and those who needed the tube reinserted after an unplanned removal.
If the CLT test shows that the fluid is less than 110 cc, removal of the tube is delayed. Doctors then assess the patient again around four hours after giving an IV dose of a medication called methylprednisolone. This medication can prevent noisy breathing in patients who failed the CLT, particularly in high-risk groups.
In case the patient still develops noisy breathing after the tube is removed, treatments including IV medication, inhaled medication and nebulizing adrenaline are started. If the patient’s condition doesn’t improve after close monitoring for up to an hour, the tube may need to be inserted again. If the tube is inserted again, the medication is continued for 24 to 48 hours, and the possibility of tube removal is considered only after repeating the CLT test. If there’s no improvement in fluid volume after 24 to 48 hours, a surgical procedure to create a direct airway (tracheostomy) might be needed, especially if the previous tube removal attempt wasn’t successful. In the meantime, an endoscopic test (using a thin, flexible tube with a light and camera attached) might be needed to examine the throat and breathing passages.
Possible Complications When Diagnosed with Post-Intubation Laryngeal Edema
After a patient has been intubated (a tube put into their windpipe to help them breathe), they may have swelling in their larynx – the part of the throat that contains the vocal cords. The majority of the time, this swelling does not cause any symptoms, or the symptoms are very minimal and go away on their own, without needing any treatment.
However, in some severe cases, this swelling can lead to a loud, harsh, high-pitched sound when breathing, known as post-extubation stridor. In fact, nearly two-thirds of patients with significant throat swelling will have this symptom. Furthermore, almost half of these patients will need to be reintubated, or have the breathing tube put back in. It’s important to understand that different people may have different types and severity of injuries to the larynx, which can affect what symptoms they experience.
Unfortunately, about 10.5% of patients with laryngeal swelling go on to have worsening breathing problems, even despite all attempts at treatment. They will need to be reintubated to help them breathe. A small number of these patients will need a surgical procedure known as a tracheostomy, where a hole is made directly into the windpipe, but this is typically only considered after monitoring their condition for 24 to 48 hours after initial treatment. Because having to be reintubated can increase the risk of health complications and even death, it’s crucial to quickly identify patients who are at high risk for developing severe laryngeal swelling and stridor. One way doctors do this is by performing a bedside cough leak test. This can help them figure out whether IV steroids might be useful as a preventative treatment.
Common occurrences and risks after intubation:
- Most patients have mild or no symptoms
- Severe cases can lead to stridor, or noisy breathing
- 50% of patients with stridor will need reintubation
- Different types and severity of laryngeal injuries can occur
- 10.5% of patients with laryngeal swelling may need reintubation despite treatment
- A few patients may need a surgical procedure called a tracheostomy
- A cough leak test can be done to identify those at high risk
Preventing Post-Intubation Laryngeal Edema
Patients who have had a breathing tube removed (a process called extubation) may experience difficulties that require the breathing tube to be reinserted (reintubation) in about 10% of cases. This could be due to trouble breathing on their own (ventilation failure) or complications from the removal process (extubation failure).
Before considering reintubation, doctors will first try other less invasive treatments and keep a close watch on the patient. It’s important to note that, reintubation usually occurs within the first 24 hours after the breathing tube is removed. It is essential for patients and their families to be aware of this possibility for any planned removal of the breathing tube.
For patients in the intensive care unit (ICU), there is a risk of developing swelling in the voice box area (laryngeal edema) after extubation which might need reintubation in about 10% of cases. The family should be informed about this risk beforehand.
Additionally, patients and their families should be aware that in a few cases, a surgical procedure to create a new airway (tracheostomy) may be needed if the patient’s condition doesn’t improve after receiving treatment for laryngeal edema for 24-48 hours following a reintubation event.
