Congenital Nasal Pyriform Aperture Stenosis (CNPAS):
Description
● Overview:
• CNPAS, a very rare cause of nasal obstruction in infants, is caused by bony overgrowth of the maxillary nasal processes.
• Because babies must breathe via their nostrils, clinical signs include apnoea, respiratory discomfort, recurrent cyanosis, and feeding difficulties.
• A term baby's CT scan must have a pyriform aperture width of less than 8 mm.
• Management: conservative (oxygen, saline infusions, McGovern nipple) versus surgical (dilatation, stenting, or sublabial route with bone drilling) if there is severe pain or insufficient nutrition.
● Discussion:
➣ Differential diagnosis: choanal atresia (including CHARGE), nasal cysts, septal hematoma, encephalocele, glioma, teratoma, nasal hypoplasia, craniofacial anomalies.
➣ CNPAS associations:
• Solitary maxillary central incisor (SMCI).
• Holoprosencephaly, pituitary deficiencies, chromosomal syndromes (Trisomy 13, 18).
➣ Investigations:
•CT scan = gold standard.
•Rule out pituitary/brain/chromosomal anomalies with MRI, endocrinology, genetic evaluation.
➣ Prognosis: Good if treated early. Risk of recurrence reduced by stenting.
● Case Report:
➣ Patient: Full-term female, first child of consanguineous parents.
➣ Perinatal history: Emergency C-section for fetal distress, low APGAR (2 at 1 min, 5 at 5 min), gestational diabetic mother.
➣ Initial course: Intubated, ventilated ×2 weeks. Failed extubation with desaturation, cyanosis, apnea, and feeding difficulty.
➣ Exam findings:
• Dysmorphic features: low-set ears, micrognathia, high-arched palate, weak cry.
• Spatula test: reduced mist bilaterally.
• Inability to pass nasogastric tube.
• No choanal atresia, cranial nerves normal, no systemic abnormalities.
➣ Investigations:
•CT: constricted anterior nasal inlet + bony overgrowth of maxillary nasal process → indicative of CNPAS.
• Hormonal test, chest X-ray, ECG, echocardiogram, brain CT: normal.
Protocol
● Treatment:
• Mild cases: conservative (oral airway, saline, decongestants).
• Severe cases: surgery (early intervention if cyanosis, apnea, feeding difficulty).
• Techniques: gradual dilation + stenting (effective in neonates due to soft bone) OR sublabial bone drilling with stents for 7–14 days.
● Problems in CNPAS
➣ Because they are obligate nasal breathers, newborns frequently exhibit respiratory distress, which manifests as apneic episodes and cyclic cyanosis.
➣ The inability to breathe comfortably while feeding is a major cause of feeding problems, which can result in poor weight gain and other issues.
➣ A weak cry, tiny chin, high arched mouth, and low set ears are examples of dysmorphic facial traits that may be associated with this condition.
➣ When a nasogastric tube cannot pass through the nostrils or when spatula testing shows less mist formation, obstruction may be suspected.
➣ Hypoxia, central hypotonia, extended hospitalisation, and secondary complications like aspiration or infections can all be consequences of delayed recognition.
● Management Strategies:
➣ Initial Stabilisation: To avoid hypoxia and other problems, immediate care to breathing and airway, including oxygen support and, if required, intubation and ventilation.
➣ Conservative measures include using a McGovern nipple or oral airway to get around the obstruction and using saline or decongestant nasal drops to try to lessen mucosal swelling. ➣Radiological Confirmation: CT scans with pyriform aperture width less than 8 mm for term infants and imaging to rule out related abnormalities confirm the diagnosis.
➣ Surgery: In situations that do not respond to conservative measures or that present with severe symptoms, surgery entails: • Anesthesia-induced nasal airway dilatation, frequently using boogies or endotracheal tubes as stents.
• The bony overgrowth in the pyriform aperture may occasionally be drilled out.
• After dilatation, stenting is utilised to preserve nasal patency and stop stenosis from returning.
➣ Postoperative care includes keeping an eye on airway patency, maintaining stents, and making sure feeding is feasible (at first via nasogastric tube or bottle).
Long-term Follow-up: Constant monitoring for related abnormalities (pituitary, craniofacial, or central nervous system defects), as well as recurrence, growth, and development.
● Nursing Interventions:
➣ Vigilant Respiratory Monitoring: Constant observation of respiratory rate and oxygen saturation to quickly identify episodes of apnoea or desaturation.
➣ Feeding Support: To avoid aspiration and guarantee nutrition, feeding should be supported using the proper methods (such as an orogastric tube or bottle feeding) until the airway is sufficiently open.
➣ Pre- and Post-operative Care:
• Getting the baby and family ready for surgery or diagnostic tests.
• Keeping an eye on nasal patency and stent placement, and monitoring for respiratory distress after surgery.
• Maintaining clearance through routine nasal care and suctioning as necessary.
➣ Support and Education: Teaching carers how to eat, recognise respiratory distress, and take care of nasal stents at home if needed.
➣ Multidisciplinary Coordination: Making sure that the teams from otolaryngology, paediatrics, endocrinology, and radiology coordinate for comprehensive care.
Notes
For more details visit https://pmc.ncbi.nlm.nih.gov/articles/PMC3282325/
