Benign Stridor Often Mistaken for Laryngospasm

Laryngospasm causes a high-pitched squeak or wheezing sound when a person is trying to breath due to abnormal vocal cord movement. Watch video regarding this condition.

Larygnospasm (the most severe form of vocal cord dysfunction) is commonly misdiagnosed as asthma and patients may go for years labelled as asthmatic even though they may not have it at all.

However, though laryngospasm is often the victim of misdiagnosis, there is a condition known as non-organic stridor which is often misdiagnosed as laryngospasm (culprit as well as victim of misdiagnosis).

Here is a video example (watch the movie clip all the way to the end) of a patient with non-organic stridor who was initially misdiagnosed with asthma, than misdiagnosed as having vocal cord dysfunction/laryngospasm before being finally correctly diagnosed with having non-organic stridor.

As you can see, the vocal cords remain apart which immediately rules out the diagnosis of laryngospasm.

What is also apparent is the wheeze or stridor noise is due to vocal cord vibration while they are apart.

The fast moving inhalation/exhalation literally rattles the vocal cord membranes just like a strong wind flaps around an American flag resulting in "noise". No need for the vocal cords to come together to create the noise. The fast moving air does it all by itself.

The existence of non-organic stridor is one of the main reasons why laryngoscopy during a "breathing attack" suspected to be due laryngospasm is so important.

It's also why I have my patients run around my office until they become symptomatic before I perform this exam. Why do an exam when breathing is completely normal???

What is the treatment? Just reassurance... Given it is the fast-moving air that is causing the noise, one simply has to slow the breathing down. No inhalers, no epinephrine, no medications are needed.

For whatever reason, by far the most common patient who suffers from non-organic stridor is a female high school athlete.

Video of Exercise Induced Vocal Cord Dysfunction

Vocal cord dysfunction (also known as paradoxical vocal cord movement) is a condition where the true vocal cords (TVC) do not move the way they are supposed to. Normally, the vocal cords move apart (abduct) when breathing and come together (adduct) when talking.

Vocal cord dysfunction is when the vocal cords adduct (come together) when breathing resulting in shortness of breath and at its worst, complete airway obstruction resulting in stridor known as laryngospasm.

The video shown here shows a patient with exercise induced vocal cord dysfunction (her breathing attacks occur only with exercise). The first part of the video shows this patient at rest breathing normally. The latter half of the video shows the patient after exercising and suffering from a mild case of vocal cord dysfunction.

Note how the vocal cords come together briefly with inhalation causing the patient to perceive inadequate breathing.

Treatment depends on finding the trigger and addressing the trigger whether it be allergy, reflux, etc. If all possible triggers have been ruled-out, neuropathic medications like neurontin and elavil can be tried. If the side effects are unacceptable or the medications just do not work, botox injections to the vocal cords can be performed.

Speech therapy can also be pursued in order to learn coping mechanisms to help a patient deal with an attack when it happens.

Olympic Athlete Hopeful With Vocal Cord Dysfunction

There was a recent article about Hannah Lupton, a heptathlete, who suffers from vocal cord dysfunction. This disorder is basically when the vocal cords come together during inhalation when it should be apart resulting in shortness of breath localized to the throat area.

Normally, during breathing, the vocal cords are apart as shown in the picture. When talking or swallowing, the vocal cords come together (TVC is True Vocal Cord).

Laryngospasm, which is the most severe form of vocal cord dysfunction, is when the vocal cords come together completely preventing any air from moving into the lungs resulting in a high pitched squeal when trying to breath. People may even faint due to lack of oxygen when this happens.

The vocal cord exercises as described in the news article may encompass these strategies among others:

METHOD 1: Breathing Technique
There are 3 steps to this particular method.

1. As soon as one feels an attack coming, SLOWLY breath in through the NOSE. DO NOT BREATH IN THROUGH THE MOUTH! Sometimes deliberately holding breath for 5 seconds prior to nasal inhalation helps.
2. More quickly exhale out the mouth with pursed lips.
3. Continue slow nasal inhalation, and quick mouth exhalation with pursed lips until the episode passes.

Why does this work? For some reason, nasal breathing reinforces the brain to keep the vocal cords apart when inhaling. Quick inhalation through the mouth seems to do the opposite and encourage the vocal cords to close which exacerbates the problem. Also, quick inhalation reinforces the Bernoulli Principle that as a fluid (air in this case) passes through a pipe that suddenly narrows (the vocal cords), the pressure actually decreases which encourages further narrowing (or vocal cord closure). Therefore, SLOW breathing helps keep the vocal cords apart! You can test this principle yourself by sucking air on a narrow short straw slowly and than quickly. You will find that the straw will tend to collapse when sucking in quickly.

METHOD 2: Straw Breathing

This method essentially forces a person to decrease the speed of breathing allowing for vocal cord relaxation. In essence, cut a regular drinking straw to half its length. When an attack occurs, place the straw in your mouth and make a tight seal. Breath thru the straw (via mouth) until attack passes.

Patients with recurrent laryngospasm attacks typically keep a straw in their pocket/purse to have immediately on hand.

METHOD 3: Pressure Point

Another manuever that may work is firm pressure in the "laryngospasm notch." Basically, with an attack, quickly with your (or somebody else's) index fingers, press very firmly just behind both your earlobes where there is a notch between the bone of your mastoid process and ear. Press deep and forward towards the nose. It should hurt. If it doesn't hurt, you are not pressing hard enough. The attack should resolve within 10 seconds. Here is an article describing this method.

METHOD 4: CPAP

This particular method applies only if laryngospasm attacks occur mainly at night while sleeping. Essentially, one uses a CPAP machine which blows air into your lungs while you sleep. This treatment helps by preventing the body from believing it is "drowning" which would result in vocal cord adduction. By having a persistent positive airflow from the CPAP device, it also reinforces to the brain to keep the vocal cords apart. At worst case, if an attack occurs, the CPAP machine helps push air into your lungs past the vocal cords. Indeed... if you ask any anesthesiologist what they do when a laryngospasm attack occurs during intubation, they'll say apply strong positive pressure by mask (along with other things of course).

Make sure you use heated humidification. Please be aware that the air pressure being applied MAY actually cause laryngospasm due to direct vocal cord irritation of the forced air. Unfortunately, there's no way to predict someone who will respond vs someone who will do worse with this treatment method.

Other Treatments

Oftentimes, the above strategies help enough that a patient finds these attacks occur less frequently with decreasing severity over time until they altogether stop. Rarely, a benzodiazepine medication will be prescribed for these attacks to help with the anxiety aspect until the strategy is internalized. Working with speech pathology has also been found to be helpful. In certain situations, laryngeal sensory neuropathy (LSN) may be contributing to VCD and treatment geared towards LSN improves VCD. Of course, treatment of the trigger whether it be allergy, asthma, or reflux is important.

In rare cases, I will consider injecting BOTOX into the vocal cords which will physically prevent the vocal cords from coming together and as such, prevent the difficulty in breathing should an attack occur. In some people, it decreases not only the severity, but also the frequency of attacks. The way BOTOX is injected into the vocal cords is shown below in the video. Please note that the vast majority of patients upon whom I perform vocal cord BOTOX injections are those suffering from spasmodic dysphonia.



Read the news article here.

Read more about vocal cord dysfunction here.