Nasal obstruction is a serious clinical scenario in the newborn infant with a large differential diagnosis. This article reviews the etiologies of nasal obstruction to aid the pediatrician in prompt evaluation, diagnosis, and treatment.
Key points
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Nasal obstruction in newborns can range in severity from a mild irritant to a life-threatening situation with potentially devastating consequences including respiratory distress and failure to thrive.
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The differential diagnosis for nasal obstruction of the newborn is vast, requiring a thorough history, physical examination, nasal endoscopy, and imaging for accurate diagnosis and treatment.
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The most common etiology of nasal obstruction is simple inflammation of the nasal mucosa, which may be managed conservatively.
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Several etiologies of nasal obstruction may warrant further evaluation and genetic workup to diagnose associated conditions.
Introduction
Newborn infants are obligate nasal breathers for the first several months of life, with more than 50% of infants desaturating if nasally obstructed. Anatomically, their entire tongue length is in contact with the hard and soft palate, and the epiglottis is superior to the soft palate, causing difficulty with oral breathing. This allows for concomitant respiration with oral intake while the infant is learning to mouth breathe in the first 4 to 6 weeks after birth. Therefore, nasal obstruction may lead to serious consequences in the neonate, including respiratory distress or failure to thrive. Thus, nasal obstruction is an important clinical entity to recognize, effectively diagnose, and treat.
Introduction
Newborn infants are obligate nasal breathers for the first several months of life, with more than 50% of infants desaturating if nasally obstructed. Anatomically, their entire tongue length is in contact with the hard and soft palate, and the epiglottis is superior to the soft palate, causing difficulty with oral breathing. This allows for concomitant respiration with oral intake while the infant is learning to mouth breathe in the first 4 to 6 weeks after birth. Therefore, nasal obstruction may lead to serious consequences in the neonate, including respiratory distress or failure to thrive. Thus, nasal obstruction is an important clinical entity to recognize, effectively diagnose, and treat.
Evaluation
History
Appropriate evaluation of nasal obstruction in newborns requires a thorough neonatal history. Signs and symptoms consistent with nasal obstruction may be described by the parents, family, or care providers ( Box 1 ). Maternal history is equally important, as maternal medical conditions, drug ingestion, and sexually transmitted diseases can be etiologies of nasal obstruction in the newborn. Familial genetic disorders, and/or prenatally diagnosed conditions should also be noted. Birth history including prematurity, length of labor, presentation, and trauma during delivery (eg, use of forceps) can implicate a potential iatrogenic cause of nasal obstruction.
Stuffy nose
Rhinorrhea
Mucus
Stertor
Snoring/snorting
External deformity
Nasal flaring
Chest Retractions
Cyanosis (± cyclical nature)
Feeding difficulties
Hyponasal cry
Failure to thrive
Dyspnea/apnea
Aerophagia with abdominal distention
Difficulty sleeping
Epiphora
Additionally, timing and onset of symptoms can provide clues as to the etiology of nasal obstruction. While bilateral nasal obstruction often presents in the neonatal period, unilateral nasal obstruction may not present until much later in life, with chronic nasal drainage, skin irritation, and congestion. Intermittent respiratory distress at birth may be associated with a ball-valving obstruction or intermittent nasal congestion associated with the physiologic nasal cycle. Thus, Apgar scores and need for resuscitation and/or intubation at birth may help delineate the severity and anatomic extent of the obstruction.
Physical Examination
The first task when assessing the newborn with nasal obstruction is to determine the degree of respiratory difficulty and establish a safe airway. Tachypnea, nasal flaring, substernal and costal retractions, and irritability suggest respiratory distress. Lethargy and cyanosis are more concerning and suggest respiratory fatigue, impending failure, and need for an immediate intervention.
If an adequate airway exists, the physical examination begins with external inspection for a gross deformity, asymmetry, or pit. Then, nasal patency should then be assessed. Anterior rhinoscopy with an otoscope may also help visualize anterior stenosis, masses, or obstructive mucus. Application of a decongestant may enhance the examination and enable the provider to compare the congested and decongested extent of obstruction to distinguish between anatomic obstruction and mucosal edema. Alternative methods of assessing patency include placing a mirror or spoon under the nare and visualizing condensation, administering nasal saline and observing bubbles, or closing 1 nare and the mouth and auscultating for air movement. Another option includes gently passing a small (5 or 6 French) catheter through the nose into the nasopharynx to confirm an open communication. Obstruction at the anterior inlet may suggest pyriform aperture stenosis, while obstruction posteriorly (approximately 32 mm) may suggest choanal atresia. Visualizing or palpating the tube through the mouth confirms that the tube is not coiled in the nose to prevent misdiagnosis. In infants with craniofacial abnormalities or visible nasal masses, care must be taken when attempting to pass a nasal catheter, as these may be associated with skull base defects and risk intracranial passage of the catheter. Additional studies to assess nasal patency include the use of a tympanometer placed at the nare to confirm or exclude a closed cavity.
Nasal Endoscopy
Nasal endoscopy is typically the next step to determine the location or causality of the obstruction. A flexible endoscopic nasal examination is a simple and minimally invasive diagnostic procedure that can be performed in the office or at bedside with no sedation by trained specialists. The examination poses essentially no risk and causes minimal distress to the patient and family. In the rare instance that an adequate endoscopic nasal examination cannot be completed at the bedside, further evaluation in the operating room may be warranted. If a nasal mass is identified on endoscopy, it should be assumed to have intracranial extent until proven otherwise. Therefore, no biopsy of a mass should be performed until appropriate imaging has been undertaken.
Imaging
There are multiple imaging modalities available for assessing nasal obstruction and the upper airway of newborns. Historically, plain radiographs with radiopaque contrast in the nasal cavity have been used to assess for obstruction. With the advent of more sophisticated imaging technology, plain films are rarely employed because of poor sensitivity and specificity. Computed tomography CT scans allow the best bony definition, and are typically the test of choice to assess choanal atresia and pyriform aperture stenosis. Suctioning of the nose before CT scanning is helpful to clear secretions that may be confused with a soft tissue or membranous obstruction. Magnetic resonance imaging (MRI) is a better choice to evaluate nasal masses to delineate intracranial involvement and extent. MRI also avoids radiation exposure in infants and may be preferentially selected over CT for this reason.
Differential diagnosis
The differential diagnosis for nasal obstruction in newborns is vast ( Box 2 ). A thorough evaluation includes careful consideration of each potential etiology, and acknowledgment that more than 1 etiology may coexist.
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Congenital Etiologies
There are countless congenital malformations secondary to aberrant embryogenesis of both the internal and external nose potentially causing nasal obstruction. These include but are not limited to: midfacial hypoplasia, craniosynostosis, arhinia (complete absence of the nose), nasal hypoplasia (congenitally absent nasal bones), complete or partial nasal duplication, single centrally placed nostril, supernumerary teeth in the nose, Thornwaldt cyst, nasopharyngeal stenosis (incomplete separation of the soft palate and posterior pharyngeal wall), and others. Of these numerous congenital causalities, the most common and clinically significant will be discussed.
Choanal atresia
Normally, the nasal cavity is connected to the remainder of the airway via the nasopharynx. Choanal atresia is the failure of the nasal cavity to connect to the naso- and oropharynx. Theoretically, this results from alterations in embryogenesis with persistence of the buccopharyngeal membrane or failure of the oronasal membrane to rupture, although no theory has been proven. It occurs in approximately 1 of 5000 to 8000 live births and is twice as common in girls. Unilateral choanal atresia is more common than bilateral involvement, accounting for 65% to 75% of cases. Comparatively, bilateral choanal atresia has more serious clinical implications and is associated with other congenital abnormalities in 50% of patients. Although most readily associated with CHARGE syndrome ( Box 3 ), it is also seen with polydactyly, Crouzon syndrome, craniosynostosis, microencephaly, meningocele, facial asymmetry, cleft palate, hypertelorism, and nasal and auricular deformities.
C: Colobomas
H: Heart abnormalities
A: Choanal atresia
R: Growth or mental retardation
G: Genitourinary anomalies
E: Ear abnormalities
Nasal endoscopy demonstrates a blind sac with a lack of communication from the nasal cavity to the nasopharynx ( Fig. 1 ). CT is the radiographic imaging method of choice and reveals narrowing of the posterior nasal cavity, medialization of the lateral nasal wall, and thickening of the vomer; it may be classified as bony, membranous, or mixed ( Fig. 2 ). Because of its association with multiple other anomalies, a genetic evaluation and thorough workup of possible associated conditions should be completed.
Treatment for choanal atresia requires surgical intervention. The timing of intervention is largely dependent on bilateral verses unilateral involvement. Newborns with bilateral choanal atresia typically present with respiratory distress at birth and may require intubation to establish an airway. In bilateral cases, surgical correction is typically performed in the first week of life and has been described via transnasal puncture, transpalatal and endoscopic transnasal approaches plus or minus postoperative stenting, mitomycin C application, and laser use. In unilateral cases, treatment is typically delayed until just before school attendance to allow growth and development of the midface, while stopping embarrassing nasal drainage and resultant skin irritation, and relieving nasal obstruction before interaction with peers.
Congenital nasal pyriform aperture stenosis
Congenital nasal pyriform aperture stenosis (CNPAS) is an uncommon etiology of nasal obstruction resulting from bony overgrowth of the nasal process of the maxilla. The pyriform aperture is a pear-shaped bony inlet comprising the most anterior and narrowest bony portion of the nasal airway; therefore, any overgrowth causes a decrease in cross-sectional area with resultant exponential increase in airway resistance and associated obstruction. Anterior rhinoscopy reveals a narrowed anterior nasal passage with bony thickening medially, typically affecting bilateral nares ( Fig. 3 ). Nasal endoscopy may not be able to be performed secondary to the small anterior passage. CT is typically the imaging method of choice and confirms the diagnosis if the pyriform aperture measures less than 11 mm at the level of the inferior meatus ( Fig. 4 ).
CNPAS may occur as an isolated anomaly or in association with absence of the anterior pituitary, diabetes insipidus, submucous cleft palate, and hypoplastic maxillary sinuses. Oral examination may reveal an absent upper labial frenulum and a prominent central mega incisor ( Fig. 5 ). It may manifest as part of the holoprosencephaly sequence (HPE), characterized by failure of the prosencephalon (forebrain) to divide into bilateral cerebral hemispheres. Suspicion of HPE warrants chromosomal analysis, genetic consultation, and possibly an endocrinology workup and electrolyte evaluation. Further imaging of the brain may be required with MRI.
