Laryngoscopy

[lwptoc]

What is Laryngoscopy?

Laryngoscopy is a medical procedure for the examination of the glottis and vocal cords. In short, it is defined as endoscopy of the larynx. This procedure can be done to provide stimulus to tracheal intubation, cardiopulmonary resuscitation, and surgeries on parts of the upper tracheobronchial tree or larynx. 

The larynx helps in talking, swallowing, and breathing. The larynx is situated at the top of the trachea and back of the throat. Larynx envelopes vocal cords which produce sound through its vibration. 

Why is laryngoscopy done?

It can be done to cure the problem of sore throat, coughing, hoarseness, and bad breath. Other conditions may include the need for removal of unwanted growth in the throat if anything is stuck inside, earache, difficulty in breathing and swallowing, blood in cough, extreme throat pain, and a case of cancer.

Laryngeal cancer

It is a cancer of the larynx. Laryngoscopy is a primary treatment for curing laryngeal cancer before other surgeries. The larynx is a voice box in the throat almost 2 inches in breadth.

The larynx consists of three parts- the first part is the glottis which houses vocal cords, the second part is a tissue that is connected to the trachea and supplies oxygen to the lungs. The third part is also a tissue above the glottis called supraglottis. 

Symptoms of cancer- sore throat, excess lump growth, sudden weight loss, frequent choking, difficulty in swallowing and breathing, and cough with blood lumps.

It occurs due to malnutrition, deficiency of the vitamin, and age normally above 40 years. It is more common in men as compared to women and for this, there are many types of laryngoscopy for treating such cancer.

Types of laryngoscopy

There are three types of laryngoscopy namely direct laryngoscopy, flexible laryngoscopy, and indirect laryngoscopy.

• Direct laryngoscopy: this method is done by guiding the laryngoscope directly into the mouth while the patient is lying on his back. Firstly, this tool is moved in the right direction then flipped to the left to move the tongue out of the way. Then a doctor detaches extra growth of lumps for testing the tissue. It can be inserted posterior or anterior towards epiglottis and with an upward and downward movement lifts it making it visible for treatment. However, this insertion depends on the type of blade of the tool. During the procedure, different types of blades or laryngoscopes are employed for particular functions. Mostly, it is used for endotracheal intubation and with biopsy. It causes discomfort in patients that’s why it is done under anesthesia. It is also not performed in the case of intact gag reflex in patients. Direct laryngoscopy is completed in almost 40-45 minutes.
• Indirect laryngoscopy: this laryngoscopy is done using a mirror rather than a direct view. It is also considered the simplest method. For this purpose, fiberoptic styles, mirror enhanced laryngoscopes, fiberoptic bronchoscopes, prism optically enhanced laryngoscopes, and video laryngoscopes. Using light, the mouth is inspected for disorder or lumps. This procedure takes almost 10-15 minutes and is conducted in a sitting position. A certain spray is used to numb the area before the examination.
• Direct fiber-optic laryngoscopy:  it is also known as flexible laryngoscopy. In this procedure, a flexible wire is used which enters through the nasal passage and reaches the throat. This wire is guided using a small telescope. Anesthesia or any other medicine is given to numb pain and discomfort in the nose. Often a decongestant is administered to expand passage and gagging is expected during the procedure. 

Types of laryngoscopes used for the procedure

There are various types of laryngoscopes present for different conditions of the problem. Some of them are conventional laryngoscopes, video laryngoscopes, and fiberoptic laryngoscopes, etc. 

• Conventional laryngoscope- this laryngoscope is designed in the shape of L with a slightly curved base. The handle of the tool contains batteries along with light fitted inside. The blade is accompanied by a number of changeable blades. It was first introduced in 1895 by Kirstein. 

Basically, two types of blades come under conventional laryngoscopes- a straight blade and a curved one. The most popular blades are the Macintosh blade and the Miller blade. The miller blade earned popularity in the straight blade category whereas the Macintosh blade excelled in the curved blade category. These blades are available from blade sizes 0 to 4 for different age groups. Phillips blade, Wis-Hipple blade, Robertshaw blade, Wisconsin blade, and Sykes blade are few other examples of curved and straight blades. These blades have specific details as some contain mirrors for a better view while others have a pipe for administering oxygen in the body. The blades were primarily made to be used by anesthetists especially in an operation theatre. With advancement, laryngoscopy came into use to treat intubation. Placements of blades differ as well like Miller’s blade is placed posterior while Macintosh’s blade is placed anterior to the epiglottis. Miller blade makes vocal cords and glottis visible by moving epiglottis out of the way. Accurate placement is necessary as a wrong procedure causes trauma to teeth. 

For infants, Wis-Hipple, Wisconsin, Miller, and Robertshaw blades are used. These blades provide a better view of glottis in infants as compared to the Macintosh blade as the size of the glottis is smaller than the epiglottis.

• Video laryngoscope- The first video laryngoscope was designed by Dr. Jon Berall in 1998. The first glidescope was introduced in 1999. In this laryngoscope, a camera is fixed on the top of the blade while components of fiberoptic are absent. 
• Glidescope- first glidescope was designed by John Allen Pacey in 2001. It consists of a high-quality camera attached with a wire to a monitor screen. It is beneficial in removing unwanted substances in the airway and facilitates proper ventilation. The blade is placed at an angle of 60 degrees for a proper view of the glottis without anterior movement of the tongue. Then a camera is placed at blade angulation. A camera is normally suspended to avoid body fluids on the screen which hinders the view. Often cameras have a wide-angle of view. Another advancement comprises the creation of heated lens technology to prevent fog on the lens. Verathon stylet is used for tracheal intubation along with a glidescope. The success rate has increased tremendously after the employment of this style.     
• Other video laryngoscopes are Storz C-Mac, McGrath laryngoscope, Pentax -AWS, Truview PCD-R, Berci DCI, and video Macintosh intubation laryngoscope. These laryngoscopes consist of monitors for guiding the cable in the trachea. This advancement made spine injury treatment easy which is, otherwise, not possible with conventional laryngoscopes.        
• Fiber-optic laryngoscopes- in this process, laryngoscopy is conducted using a flexible fiber-optic rhinoscope or bronchoscope. It can or can not be performed under anesthesia, it is employed so that during phonation, vocal cords are easily diagnosed. It is used as an alternative to conventional direct laryngoscopy. Some other fiber-optic tools are Wuscope, Upsherscope, and Bullard scope. They are highly preferred for curing chronic intubation. Laryngoscopes differ in the size of handle and blade to provide efficient treatment. Straight blade laryngoscopes are mostly used for adults undergoing intubation treatment. Curved blade laryngoscopes are used in infants or pediatric patients.                                                                                               

FAQs 

What is the cost of laryngoscopy?

Cost ranges between $180 and $400. Other things such as injections and medicines can add up to make a hefty price. However, it costs less if a patient has insurance cover.

What are the side effects of laryngoscopy?

Bleeding, pain around the area, swelling, leakage of body fluids like saliva, infection due to virus or bacteria and problem in eating. Most of these side effects disappear after some time. 

How to prepare for laryngoscopy?

Avoid all previous medications before surgery, a patient must be accompanied by someone, basic physical tests must be completed and do not eat anything before surgery for at least 10 hours. 

How much time is needed for laryngoscopy?

Laryngoscopy takes almost 40 to 45 minutes. Preparation and recovery take a few more hours as it is necessary to overcome the effect of anesthesia.

Is laryngoscopy painful?

No, laryngoscopy is not painful as it is performed by administering anesthesia to the patient. Discomfort occurs during recovery for some time which vanishes over time.