Nasal Airway Obstruction - Causes, Features, Tests, and Treatment

Introduction

Nasal airway obstruction is not a disease but refers to a block or interference to the free flow of air through the nasal passages due to an underlying disease or inflammatory response in the body. About 70 % of the oxygen that reaches the lungs is through nasal breathing; this is limited when the nasal passage is obstructed. Nasal airway obstruction (NAO) has been characterized as a major source of patient discomfort and financial strain and is a frequent presenting symptom in otolaryngology practices. It is very common, affecting around 20 million people in America alone. However, it could be an emergency in newborn babies and requires prompt correction.

What Causes Nasal Obstruction?

Anything that can hinder the movement of air in and out of the nose. Causes can be broadly categorized as follows:

1. Anatomical - Abnormalities in two main structures are associated with nasal obstruction. The nasal septum, present in the midline between the two nostrils, is composed of cartilage and bone and supports the structure and function of the nose. If it is deviated to one side, either due to a variation in normal development or trauma, then the airway is obstructed. Septal deviation is common; all septal deviations do not cause nasal airway obstruction. The turbinates are paired bony structures on either side of the nose covered by mucosa that humidifies the air we breathe. When the turbinates are enlarged due to chronic inflammation or due to developmental variation, they block the nasal passage. Nasal polyps are benign growths that may occur in the nose. Enlarged adenoids and nasal tumors also cause obstruction.Enlarged adenoids and nasal tumors also cause obstruction. The nasal valve which is the narrowest part of the nasal passage composed of soft tissues. Nasal valve stenosis occurs if the soft tissues collapse and obstruct the airflow which may be a result of previous surgery or simply an anatomical variation.

2. Medical Causes - Patients must be questioned about using sympathomimetic amines, such as ephedrine/phenylephrine and imidazoline derivatives, as chronic intranasal decongestants because those with allergic rhinitis and chronic rhinosinusitis frequently self-medicate prior to specialty assessment (oxymetazoline and xylometazoline). These drugs put users at risk of developing rebound nasal congestion and rhinitis medicamentosa syndrome, which usually develops 5 to 7 days after using the intranasal drug.

3. Trauma - Accidents, falls, contact sports, etc., can lead to a septal fracture or fracture of facial bones. Complications such as septal perforations, adhesions, nasal stenosis, and empty nostril syndrome may arise from accidental trauma and sinonasal surgery. Through three different processes, these conditions may cause obstructive symptoms to develop: Airflow is physically blocked, sinusitis is caused, and airflow feeling is compromised.

4. Rhinitis or Sinusitis - Allergic rhinitis and chronic sinusitis causing nasal congestion block the passage of air completely or partially. Common cold or flu is the commonest cause of obstruction. Environmental factors like polluted air with dust, sinus infection, etc., also cause nasal blocks.

What Are the Features of Nasal Obstruction?

Obstructed nasal passage causes discomfort and stuffiness. It is hard to breathe through the nose, and you are often forced to breathe through the mouth. This can lead to dryness of the mouth. Recurrent causes of nasal obstruction during developmental stages can result in the habit of mouth breathing, which has adverse effects on the developing dentition and occlusion. Mouth breathing can cause problems with posture, narrow jaws, and spaced dentition and affects the facial structure. Other symptoms depend on the underlying cause; sinusitis is associated with facial pain and headaches, and a common cold can leave you with a runny nose. Nasal obstruction affects the performance of athletes. Noisy breathing and snoring are associated with an obstructed airway. In infants nasal obstruction manifests as spells of apnea (difficulty in breathing) while feeding, running nose, etc.

What Are the Tests for NAO and How Is It Identified?

1. Anterior Rhinoscopy: It can be done to examine the nasal cavities, secretions, mucosal surfaces, turbinates, septal position and presence of foreign bodies.

2. Posterior Rhinoscopy: This procedure may be performed to examine to the posterior part of the nasal cavity and the nasopharynx. The structures visualized include the posterior end of the nasal septum and the turbinate, the upper surface of the soft palate, the eustachian tube opening, and the fossa of rossenmuller.

3. Diagnostic Nasal Endoscopy: It is used to visualize the inside of the nose and sinuses. It may also be used to remove polyps, mucus, and other masses that might be present in the nasal cavity or sinuses, or to retrieve tissue for biopsy.

4. X-ray of the Nose and PNS (Paranasal Sinuses): It can help detect sinusitis or infection, and the presence of a tumor.

5. CT (Computed Tomography) or MRI (Magnetic Resonance Imaging) of Nose and PNS: Computed tomography and magnetic resonance imaging are advanced imaging techniques that can detect any abnormalities or pathology in the nasal passage or sinuses.

Grading System - NOSE Score (Nasal Obstruction and Symptom Evaluation Score) - This is a simple test that can assist determine the severity of a person's nasal obstruction. There are five questions with values 0 to 4 that are circled for each question. The sum of the score for the five questions is then multiplied by 20 which gives a score out of hundred. The questions are as follows:

• Nasal congestion or stuffiness.

• Nasal blockage or obstruction.

• Trouble breathing through the nose.

• Trouble sleeping.

• Unable to get enough air through the nose during exercise or exertion.

The values stand for 0 (Not a Problem), 1 (Very Mild Problem), 2 (Moderate Problem), 3 (Fairly Bad Problem), 4 (Severe Problem).

The correct diagnosis of the underlying cause of a patient's nasal obstruction symptoms depends on taking a thorough medical history and performing a head and neck examination. It is crucial to ask patients about any over-the-counter drug use, potential allergic triggers (like pets), and prior surgeries because some patients will downplay past cosmetic surgery. Physical examination findings could include midface deformities that could be the outcome of persistent mouth breathing. The traditional allergic greeting or shiners may be seen in people with allergic rhinitis. Facial nerve function should be examined because paralysis of the nasal ala's splinting muscles could cause a functional blockage of the nasal airway. Chronic nasopharyngeal inflammation, adenoid hypertrophy, or an obstruction mass close to the eustachian canal can all manifest as middle ear effusions. Examining the nose should take airflow dynamics and areas of greater resistance into account. Focusing on external support structures first, evaluating internal support structures next, and then assessing internal soft-tissue structures is one recommended approach.

How Is Snoring Related to NAO?

Nasal blockage or congestion can contribute significantly to snoring, poor sleep, and sleep-disordered breathing. Nasal stuffiness or narrow or collapsing nostrils are common causes of nasal snoring. As nasal breathing becomes difficult due to congestion, the body urges you to start mouth breathing, which is not the best approach to getting air into your lungs. Mouth breathing generates more negative pressure (vibrating) behind the soft palate and uvula, which can result in snoring during sleep.

If there is prolonged or repetitive nasal congestion and snoring, obstructive sleep apnea (OSA) which could be a serious disorder involving spells of pauses in breathing caused due to a block, is a possibility. Disturbed sleep further leads to fatigue, decrease in productivity, increased risk of accidents, depression, or alteration in mood, and negatively affects the quality of life.

What Is the Treatment?

Treatment starts with identifying and treating the underlying cause of the obstruction. Anatomical causes are not relieved by medication or home remedies and need surgery.

Avoid known allergens that can trigger allergic rhinitis or sinusitis. Some measures that can be taken at home include steaming, avoiding sleep on your back, avoiding smoking, etc. Depending on the severity of symptoms your doctor may prescribe the use of topical nasal steroids or antihistamine spray, oral antihistamines or steroids, and antibiotics (if a bacterial infection is present). Surgical procedures include septoplasty (correction of a deviated septum), image-guided endoscopic sinus surgery (restores ventilation and drainage in the nasal cavity), turbinate reduction, and nasal valve surgery.

Conclusion

Nasal airway obstruction is the commonest complaint reported, caused due to various factors that limit the movement of air through the nasal passages and to the lungs. Anatomical variations causing obstruction require surgery. Chronic nasal obstruction could be related to snoring and a condition called obstructive sleep apnea. Various at-home measures and medications can offer relief.