104 Stertor and Stridor
Stertor is noisy breathing caused by turbulence due to partial obstruction of the upper respiratory tract (URT) above the larynx.
Stridor is noisy breathing caused by turbulence due to partial obstruction of the URT at the laryngeal or tracheal level.
Stertor and stridor may co-exist. Obstruction below the trachea, for example, due to a foreign body or consolidation from infection, will typically cause an expiratory wheeze. This can sometimes be confused with stridor in the clinical setting.
Stertor may present at any age and may be caused by single or multiple levels of obstruction to the airway above the larynx.
104.2.1 Congenital (present at birth) Stertor
Neonates are obligate nasal breathers and complete nasal obstruction will cause a respiratory arrest. Partial nasal obstruction at birth may progress to total nasal blockage with development, depending on the cause and its extent.
Choanal stenosis or atresia.
External nasal deformity due to a craniofacial abnormality or nasal trauma.
Deviated nasal septum from birth trauma or congenital nasal mass.
Congenital nasal mass such as the following:
1. Dermoid, nasoalveolar, dentigerous and mucous cysts deforming or projecting into the nasal airway.
2. Masses arising from the anterior skull base such as a meningocele, encephalocele, meningoencephalocele or glioma.
Craniofacial abnormality, especially Apert’s and Crouzon’s syndromes. Congenital cystic or solid mass such as a dermoid or haemangioma.
Oral cavity and oropharynx
Micrognathia to a craniofacial abnormality, especially Treacher Collins and Pierre Robin syndromes. In these, a small mandible and hypotonia allows the normal-sized tongue to fill the mouth and, by falling backward (glossoptosis), obstruct the oropharynx.
True macroglossia, either from congenital masses such as a haemangioma or lymphangioma or as part of a syndrome such as Beckwith–Wiedemann syndrome, obstructs both the oral cavity and oropharynx.
Relative macroglossia due to a small mouth without micrognathia, but normal tongue, most frequently in children with Down’s syndrome.
Lingual thyroid and thyroglossal cyst.
Congenital neurological conditions causing hypotonia.
Congenital neck masses, such as a cystic hygroma, causing extrinsic compression of the upper airway.
104.2.2 Acquired Stertor
Trauma causing external nasal and septal deviation, septal haematoma or a secondary septal abscess.
Rhinitis, rhinosinusitis and nasal polyps.
Iatrogenic, from nasal stenosis or intra-nasal adhesions following nasal surgery including septorhinoplasty.
Acquired nasal masses, which may be benign such as meningocele or malignant such as an olfactory neuroblastoma, lymphoma or sinus carcinoma.
Systemic diseases causing nasal obstruction, such as Wegener’s granulomatosis or sarcoidosis.
Nasopharyngeal carcinoma or lymphoma.
Iatrogenic such as nasopharyngeal stenosis from palatal surgery.
Acute tonsillitis, especially to infectious mononucleosis.
Parapharyngeal and retropharyngeal abscess.