What is this post about?
This post talks about superior laryngeal nerve block, which is a promising innovative treatment option for patients with chronic cough, particularly those with laryngeal hypersensitivity or neurogenic cough.
Superior laryngeal nerve block adds to the treatment options by targeting the nerve responsible for the cough reflex with a safe, quick, and minimally invasive procedure. It can provide significant relief and improve quality of life in what can be a very debilitating condition.
This post explores the role of superior laryngeal nerve block in managing chronic cough, including the procedure, risks, and effectiveness.
What is chronic cough?
Chronic cough is defined as a cough lasting more than eight weeks in adults or four weeks in children. It can result from a variety of underlying conditions, including:
- Asthma
- Gastroesophageal reflux disease (GERD)
- Chronic sinusitis
- Chronic obstructive pulmonary disease (COPD)
- Infections of the chest, throat, and sinuses.
- Side effects of medications, such as ACE inhibitors.
In some cases, chronic cough may be idiopathic, hence no specific cause can be identified. This can lead to frustration for both patients and healthcare providers. Traditional treatments, such as medications and lifestyle modifications, may not always provide relief, prompting the exploration of alternative therapies like superior laryngeal nerve block.
How does superior laryngeal nerve block work in chronic cough?
The superior laryngeal nerve is a branch of the vagus nerve that provides sensory innervation to the larynx and surrounding structures. It plays a key role in the cough reflex, which is triggered by irritation in the laryngeal area. A superior laryngeal nerve block involves injecting a local anaesthetic and, or steroid near the superior laryngeal nerve to temporarily disrupt its function, thereby reducing the cough reflex.
Superior laryngeal nerve block is particularly effective for patients with chronic cough caused by hypersensitivity of the laryngeal area or conditions such as neurogenic cough. By blocking the nerve signals responsible for the cough reflex, superior laryngeal nerve block can provide significant relief for patients who have not responded to other treatments.
How do we perform a superior laryngeal nerve block?
Superior laryngeal nerve block for chronic cough is a minimally invasive procedure typically performed in an outpatient setting. Here’s an overview of the steps involved:
1. Preparation
The patient is positioned comfortably, usually sitting upright. The neck area is cleaned and sterilized to prevent infection.
2. Localization
The healthcare provider identifies the superior laryngeal nerve using anatomical landmarks or ultrasound guidance to ensure precision. It is located just above and towards the back of the voice box.
3. Injection
The doctor inserts a small needle near the superior laryngeal nerve, and injects local anaesthetic, e.g. lidocaine or a combination of anaesthetic and steroid. This may be performed on one or both sides of the neck.
4. Monitoring
The patient is monitored for a short period to ensure there are no immediate complications.
The procedure is generally quick, taking about 10-15 minutes, and most patients experience minimal discomfort. The effects of the block can last for several weeks to months, depending on the individual and the injection used.
What are risks of superior laryngeal nerve block?
Superior laryngeal nerve block for chronic cough is considered safe, however like any medical procedure, it carries some risks. These may include:
- Numbness of the throat. This is expected if local anaesthetic is used in the injection. It may last an hour or up to several hours. Be careful not to eat or drink in the first hour after the procedure or until the numbness wears off.
- Temporary swallowing difficulty. This is also likely to occur due to the temporary loss of sensation in the throat. Again, expect this to return to normal usually within an hour, or sometimes a few hours.
- Temporary hoarseness or voice change. Due to the proximity of the superior laryngeal nerve to the vocal cords. This is usually minor if it occurs at all.
- Pain or discomfort at the injection site. Usually mild and short-lived.
- Infection. Rare but possible. Usually avoided by following proper sterile techniques.
- Allergic reaction. To the anaesthetic or steroid used. This is rare.
- Nerve injury. Can occur if the needle damages the nerve but is extremely rare.
- Skin changes. Steroids can cause the skin to become thinner or change colour. This may occur, particularly when repeated injections are needed.
It is important to discuss these risks with your doctor to determine if superior laryngeal nerve block is a suitable option for your condition.
Will I need repeated superior laryngeal nerve block for my chronic cough?
The need for repeated superior laryngeal nerve block depends on the individual patient and the underlying cause of their chronic cough. Some patients experience long-lasting relief after a single injection, while others may require repeated blocks to maintain symptom control.
Your doctor will evaluate your response to the initial block and develop a personalized treatment plan. The doctor may also recommend complementary therapies, such as speech therapy or medications, to enhance the effectiveness of superior laryngeal nerve block.
How do I find out more about superior laryngeal nerve block for chronic cough?
Dr Lau is experienced in managing throat, voice, and swallowing conditions and performs superior laryngeal nerve block for chronic cough.
Read more about services for throat, voice and swallowing disorders at Advanced ENT Centre.
Read more about conditions related to the throat, voice and swallowing.
Contact us at Advanced ENT Centre to arrange an appointment.