Airway obstruction: Clinical sciences

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Introduction0:00–0:39

An airway obstruction is defined as the inability to move air, or ventilate, from a direct occlusion or anatomic narrowing.
It requires an immediate assessment and swift intervention, since it can be fatal if left untreated. There are many causes that can lead to airway obstruction, including trauma, tracheal narrowing, foreign body aspiration, mucus plugging, malignancy, and deep neck infection.
Keep in mind that all of these causes have the potential to cause hemodynamic instability due to respiratory failure, especially trauma and foreign body aspiration.When assessing a patient with signs and symptoms suggestive of airway obstruction, you should first perform an ABCDE assessment to determine if the patient is unstable or stable.

Unstable patient0:39–4:36

Be sure to look for red flags of impending airway compromise like stridor, tachypnea, accessory muscle use like gasping or nostril flaring, as well as bleeding in the nasopharynx or the oropharynx, large or expanding neck hematoma, crepitus in the neck or upper chest, and tracheal deviation.
If the patient is unstable with red flags, you must initiate acute management right away to stabilize their airway, breathing, and circulation.
The goal here is to maintain oxygenation above 90% initially with a high-flow nasal cannula or non-rebreather. However, if the patient desaturates or cannot protect their airway, proceed with rapid sequence intubation.
This involves administering an induction agent like etomidate; and a paralytic agent like succinylcholine or rocuronium.
Once medications start working, you can intubate the patient. Here’s a clinical pearl!
If airway obstruction is anticipated, make sure to have multiple sizes of small endotracheal tubes available. Keep in mind that, although securing the airway is the top priority, the workup will likely require laryngoscopy and bronchoscopy.
Now, if intubation is unsuccessful after 3 attempts or you cannot maintain oxygenation above 90%, consider cricothyroidotomy to create an emergency surgical airway.
Once you’re done securing the airway, make sure to establish IV access and administer fluids before continuing with your assessment.
After acute management is initiated, obtain focused history and physical examination. If your patient is intubated, you may need to obtain history from family members or paramedics.
Be sure to ask about any head, face, or neck trauma, changes in levels of consciousness, and presence of dyspnea prior to presentation.
On physical exam, look for any signs of maxillofacial, neck, and chest injuries.If you suspect trauma-induced airway obstruction, obtain a chest x-ray.
Now, sometimes it might show associated injuries like pneumothorax, tracheal deviation, pneumomediastinum, or rib fractures.
However, in some cases, the x-ray will be completely normal. Even though it is normal, the patient is still having a traumatic airway obstruction from a tracheal crush injury, so you need to move on to management.
Keep in mind that subcutaneous emphysema and mediastinal air will not cause airway obstruction, since the cartilage in the trachea is stronger than the air pressure.Once the diagnosis of traumatic airway obstruction is confirmed, your next step is to establish a secure or definitive airway.
You can use high-flow oxygen or a bag-valve mask to provide oxygen. Now, in some patients, like the ones with maxillofacial trauma, bag-valves are contraindicated.
If they are not already intubated, consider rapid sequence intubation and possibly a surgical airway like cricothyroidotomy or tracheostomy.
On the other hand, if the patient has supraglottic injuries, you can skip the intubation and go directly to securing a surgical airway.
Keep in mind, if the airway obstruction is distal in the trachea, a surgical airway will not help relieve the obstruction.
Lastly, once the patient is able to maintain oxygenation above 90% and no longer has signs of impending airway compromise, continue observing them.Okay, now that unstable patients are taken care of, let’s talk about stable patients.

Stable patient4:36–4:48

Your first step here is to obtain a focused history and physical examination. Alright, let’s start with tracheal narrowing.

Tracheal narrowing4:48–6:43

This can occur with tracheal stenosis or tracheomalacia. Tracheal stenosis is most often a scar tissue that develops as a complication of endotracheal intubation or tracheostomy; while tracheomalacia is a tracheal weakness and collapse, which can be congenital or acquired as a complication of endotracheal intubation or tracheostomy.Now, your patient might report dyspnea, as well as persistent cough, sputum retention, and frequent respiratory infections.
Additionally, some patients may have a history of prior endotracheal intubation or tracheostomy. On a physical exam, you might notice tachypnea, wheezing, or stridor.
At this point you can suspect tracheal narrowing, so your next step is to confirm the diagnosis. To do this, order a chest x-ray, neck and chest CT, and a bronchoscopy.
The chest x-ray may show the airway narrowing, but can also often be normal; however, it is still useful to establish a baseline evaluation of the lungs and rule out other conditions.
Next, neck and chest CT allows you to assess the location, approximate length, and severity of the narrowing. Lastly, the gold standard is bronchoscopy, since it allows direct visualization of the narrowing to confirm the diagnosis.
Once confirmed, mild asymptomatic cases usually don’t need treatment other than observation. On the flip side, severe or symptomatic cases require treatment to restore airway patency, either with local bronchoscopic therapy or with surgery.

Foreign body aspiration6:43–8:16

Let’s go back to H&P and talk about a different presentation. The patient might report chest pain, hemoptysis, and recurrent pneumonia.
On physical exam, if you find wheezing and unilateral decreased breath sounds, you should be suspicious of a foreign body obstruction.
This is more common in children, but also among older adults with stroke-related dysphagia, Alzheimer, or Parkinson disease, as they are at an increased risk for aspiration.
Now, if you suspect foreign body obstruction, order a chest x-ray to visualize it. However, unless the object is radiopaque, you might not see it.
Next, order a chest CT to better visualize the object and get an idea of its location. Usually, CT shows the foreign body even if it is not radiopaque.
With this finding, you can diagnose airway obstruction due to a foreign body.Let’s move on to treatment. If the foreign body is supraglottic or glottic, perform a laryngoscopy or rigid bronchoscopy to retrieve the object.
For subglottic or tracheal foreign bodies, flexible bronchoscopy can be used instead. Keep in mind that post-retrieval subglottic edema can develop in some cases.
It can be treated with parenteral glucocorticoids, nebulized epinephrine, and helium-oxygen or heliox therapy.A similar cause of airway obstruction is mucus plugging.

Mucus plugging8:16–9:36

Your patient may report dyspnea, cough, recurrent respiratory infections, and may have a history of pulmonary disease, such as COPD, asthma, or cystic fibrosis.
On physical exam, you may find wheezing and unilateral decreased breath sounds.Now, if you suspect mucus plugging, order a chest x-ray and chest CT, which can help visualize the mucus plug and get an idea of its location.
X-ray can show the classic finger-in-glove sign, meaning opacities that typically originate from the hilum and are directed to the periphery; while CT findings will show filling defects within the bronchi.
With these findings, you can diagnose partial or complete airway obstruction due to mucus plugging.Treatment involves helping mucociliary clearance with chest physiotherapy, including chest percussion, positive expiratory pressure, and forced expirations followed by a cough to help clear secretions; while severe mucus plugging can be removed with flexible bronchoscopy.
Lastly, remember to treat the underlying condition causing the mucus plugs.Alright, it’s time to go back to H&P and talk about another cause of airway obstruction.

Malignancy9:36–10:42

Some patients might report dyspnea, cough, and hemoptysis, as well as odynophagia or dysphagia, dysphonia, and weight loss.
They might also have a history of smoking or alcohol use. When it comes to physical examination, you’ll usually find stridor or wheezing and tachypnea.
In this case, you should be suspicious of airway obstruction secondary to malignancy. As before, your next step is to order a chest x-ray and a chest CT, which will allow you to determine the location and extent of the tumor.
The tumor may also be obstructing an associated bronchi, resulting in lobar collapse. With these findings, you can diagnose airway obstruction secondary to malignancy.
As for the treatment, call the surgical team for a consultation about further management.Okay, let’s go back to the H&P one more time.

Deep neck infection10:42–12:40

The patient might report dyspnea, dysphagia, and dysphonia, with signs of infection like fever and neck pain. Next, a physical exam might reveal tachypnea, trismus, and signs of a local infection like edema and erythema of the neck, induration, asymmetry, and lymphadenopathy.
If you see these, you should suspect an airway obstruction from a deep neck infection. Your next step is to order a neck x-ray, followed by a CT of the neck with IV contrast.
You can expect to see soft tissue stranding and swelling, as well as ill defined or a rim-enhancing fluid collection in the deep spaces of the neck.
Depending on the severity and extent of the infection, you might see a mass effect narrowing the trachea. At this point, you can diagnose an obstruction due to a deep neck infection.Once you have radiographic confirmation of the infection, you can move on to treatment.
First, consider early intubation to prevent impending airway compromise. Next, treat the infection itself.
Large, well-circumscribed abscesses or fluid collections need to be drained surgically and treated with empiric antibiotics.
Some possible antibiotic choices include a penicillin or vancomycin plus an aminoglycoside, or a penicillin and beta-lactamase inhibitor combination.
Coverage for methicillin-resistant Staphylococcus aureus, or MRSA, should be included as part of the initial management in patients with comorbidities such as diabetes or a history of IV drug use.
Make sure to send cultures from the abscess and tailor the antibiotics accordingly. Finally, don’t forget to provide pain management.

Review12:40–14:15

Alright, as a quick recap… An airway obstruction is an inability to move air either due to a direct occlusion or anatomic narrowing.
In an unstable patient, the airway obstruction is likely secondary to traumatic causes, so you must quickly establish a secure airway either via endotracheal intubation or surgical airway.
Next, evaluate them with an x-ray, and maintain a stable airway. In stable patients, causes of airway obstruction include tracheal narrowing, foreign bodies, mucus plugging, malignancy, and deep neck infections.
Tracheal narrowing can occur with tracheomalacia or tracheal stenosis, and when severe or symptomatic, requires treatment to restore airway patency, either with local bronchoscopic therapy or surgery.
Foreign body obstruction requires removal of the object under direct visualization and steroids for subsequent inflammation.
Mucus plugging can be associated with pulmonary diseases like COPD, asthma, or cystic fibrosis, and treatment involves chest physiotherapy; while severe mucus plugging can be removed with flexible bronchoscopy.
Patients with malignant obstruction need surgical consultation for further management, while deep neck infections need surgical drainage and antibiotics.
Airway obstruction: Video, Causes, and Symptoms | Osmosis