How to Recognize and Treat Laryngospasm in Dentistry

Laryngospasm in a dental office is always a medical emergency. Although it may resolve on its own, hoping for the best in such situations would be a terrible mistake. Immediate action is needed to open an airway as soon as possible. Having in mind people simply do not perceive dental services as something that has a potential to put their lives in danger, dentists are extremely sensitive about thoughts of medical emergencies in their offices. 

This blog from http://https//www.dental911training.com/ will provide you basic info about Laryngospasm, how to prevent it, its causes, risk factors, and treatment. 

What is Laryngospasm?

Laryngospasm is a muscular contraction of the vocal folds. It is an uncontrolled and involuntary act. The contraction may obstruct the airway completely or partially.  Laryngospasm that obstructs airway entirely usually lasts less than 60 seconds. The condition is also known as “dry drowning”. In some people, it is particularly frightening experience, since the spasm lasts until they lose consciousness (and then disappears). Partial spasms tend to last longer. Laryngospasm is occurring more often in children, because of the tight airways, but can happen in adults with presenting risk factors. The condition resolves on its own. 

    Unlike above-mentioned laryngospasm, anesthesia induced one can be a life-threatening condition, and without appropriate intervention, it may lead to death. 

Anesthesia in dentistry- who are the right candidates? 

PSA is a part of everyday dental practice. Since some procedures require more complex types of anesthesia (such as general anesthesia), the subject of discussion in this article will be PSA only. 

American Society of Anesthesiologists issued in 1941 a simple physical classification system that supposed to, somehow, stratify the patients with different risks into appropriate categories. The system has been revised many times since and today it is used as a patient classification standard among anesthesiologists around the world. 

According to the requirements of safe practice, only ASA 1 and 2 patients can receive PSA (procedural sedation) outside the operating theatre. 

ASA Physical Status (PS) Classification System

    ASA PS 1

-    Normal, healthy patients. The patient has no psychologic, psychiatric nor organic diseases.

-    Very young and very old are excluded from this category. 

-    Non-smoker and minimal alcohol use. 

-    The overall health and exercise tolerance is unremarkable. 

ASA PS 2

-    A patient with a systemic disease, a mild form, well controlled. The patient has no functional limitations. 

-    The disease includes only one body system, or if systemic, it has no systemic effects/ complications (well-controlled hypertension or diabetes without any complications). 

-    In this category are smokers without smoking complications (chronic obstructive pulmonary disease- COPD). 

-    Social alcohol drinkers

-    Pregnancy

-    Obesity (BMI 30-40)

ASA PS 3-6

ASA PS 3-6 categories include patients that cannot be classified into any of the above. These categories include severe systemic diseases (for example diabetes with complications, Chronic Heart Failure, stable angina, etc.) diseases that are a constant threat to life (unstable angina, symptomatic Chronic Heart Failure, symptomatic COPD, etc.), patients who are not expected to survive without surgery (severe head trauma, internal bleedings, etc.), and declared brain-dead patients. 

What are the risk factors?

The risk of laryngospasm may be increased due to a patient, sedation, anesthetic, and procedure-related factors. As you will see, in the context of dentistry, just a few of the risk factors are manageable. Knowing who are the vulnerable groups of patients and avoiding PSA in such cases is the only way to prevent unpleasant complications during the intervention. 

Anesthetic and surgery factors

-    Insufficient depth of anesthesia. 

-    Airway irritation.- as simple as saliva or irrigation.

-    The presence of blood and mucous in the upper airways, pharynx, and larynx.  

-    Shared airway (necessary in some dental procedures). 

Patient-related factors

-    There is an inverse correlation with age- children are at greater risk than adults. 

-    Patients with asthma are at 10 times increased risk of getting the laryngospasm during intervention. 

-    Smokers are at greater risk, and two-day abstinence from smoking is recommended before procedure. 

-    Obese patients with obstructive sleep apnea. 

-    GERD (Gastro Esophageal Reflux Disease)- Chronic inflammation of the upper airways contributes to the airway irritation. Patients with GERD complications (laryngospasm during night, burning sensation in chest or mouth, obvious teeth deterioration due to the disease, are at high risk of laryngospasm.  Also, acid aspiration during an intervention may cause it. 

-    Anomalies of the airways (subglottic cysts, tracheal stenosis, laryngeal papillomatosis, Piere Robin Syndrome, etc.) 

-    Other health conditions that can directly or indirectly cause airway obstruction (by triggering some local or systemic reaction, for example, Parkinson’s disease during withdrawal treatment). 

-    Previous laryngospasm episodes during surgical interventions, night choking episodes, etc. 

Treatment

In order to treat laryngospasm efficiently, it is crucial to have a clear plan of action. First, make sure you are dealing with a laryngospasm. After excluding apparent causes of obstruction, proceed with the procedure for laryngospasm treatment. 

1. Suction, removing the offending source if possible

Any blood, mucous or other substances should be removed from the back of the throat. Laryngoscopy (if needed) and suction maneuver should be performed extremely cautious since those actions per se can trigger or worsen the laryngospasm (read anesthetic and surgery risk factors section). 

Make sure there are no pieces of equipment, tooth fragments, etc. that may be the cause of airway irritation and subsequent spasm. 

2. Head tilt/chin lift maneuver

    The purpose of a maneuver is to prevent tongue obstructing an airway. Just like its name says- to perform it tilt the head of a patient backward and bring the chin up. The maneuver is performed in unconsciousness patient. Does it resolve laryngospasm? No, it won’t resolve it per se, but as soon as the patient loses consciousness, the relaxation of larynx muscles begins, and the spasm should subside. The maneuver will prevent tongue obstructing the upper airways. Pay attention if the patients breathe (look, listen, feel principle). As the breathing establishes again and oxygen level in blood increases, the patient will regain consciousness. 

OR..... Laryngeal mask airway (LMA)

To place the LMA successfully, follow these steps:

- Before insertion, inflate and then deflate the cuff, pressing it on the hard surface.

- Lubricate the posterior LMA surface- it will ensure LMA slides to its position smoothly. Do not lubricate the laryngeal side of LMA. 

- Slightly flex patients head. This will loosen the throat and make more room for the LMA to set into the position. 

- Hold the LMA the way you hold a pan. Index finger fingertip should be placed at the point of junction between tube and cuff. 

- Open patients mouth as wide as you can. To open them, use your non-dominant hand to open mouth and your dominant to place LMA. 

- Insert LMA far back until it seats, overlying the larynx. When the tip of the mask reaches the back of a tongue, LMA is set (in most patients!)

- Inflate the LMA carefully. As the cuff inflates, you should observe the area around larynx lifts. 

- Check ventilation.

- Attach the LMA to the ventilation bag

- Keep ventilating at a steady rate of 10-12 respirations per minute.

OR..... Positive pressure ventilation with a bag; valve-mask device

The maneuver is easier to perform than LMA placement, but keep in mind that you will need to apply a strong grip to ensure a tight seal between the mask and patient’s face. The patient should lie on a flat surface. Use your non-dominant hand to place and hold a mask. Thumb and index finger should hold a mask (placed in a “C” shape around the mask), while third, fourth and fifth finger of the same hand should grab the jaw bone forming an “E” shape. The patient’s head should be tilted backward while performing the ventilation. Keep ventilating at the steady rate of 10-12 respirations per minute. Keep in mind that, just like in case of LMA, the tight seal between the airway and mask is the most important for successful ventilation.

Laryngospasm in a dental office is always a medical emergency. Be prepared to act with any of the above treatments. The best way to be prepared is to engage in learning activities and mock emergency drills for your dental team. Additional resources such as textbooks, emergency manual and mobile Apps can assist the dental practice in maintaining necessary skills needed when medical emergencies arise. 

http://https//www.dental911training.com/dental-911-app