Respiratory System Anatomy and Lung Development

The vocal cords.

Gas exchange.

At 5–7 weeks of gestation.

Lung buds arise from the foregut and branch into the primary bronchi.

At 7–17 weeks of gestation.

The terminal bronchiole.

Gas-exchanging structures have not yet formed.

At 17–26 weeks of gestation.

Respiratory bronchioles develop and vascularization increases.

At 26–36 weeks of gestation.

Surfactant.

Around 36 weeks of gestation.

They continue to develop and increase the lungs' gas-exchange capacity into childhood.

A congenital obstruction of one or both posterior nasal passages.

Choanal atresia.

Failure of the oronasal membrane to rupture.

CHARGE and VACTERL syndromes.

Coloboma, heart defects, choanal atresia, growth and developmental retardation, genital or urinary abnormalities, and ear abnormalities.

Vertebral, anal, cardiac, tracheoesophageal, renal, and limb abnormalities.

It may be asymptomatic or associated with recurrent respiratory infections.

Cyanosis at rest that improves with crying.

Air can enter through the open mouth.

Difficulty breathing, sucking, and swallowing during feeding.

A nasal catheter cannot be passed through the nasal passage.

CT of the nasal passages.

Stabilize the airway with an oral airway or intubation.

Transnasal repair after stabilization.

Dermoid and epidermoid lesions.

Thyroid, cricoid, and epiglottic cartilages.

Arytenoid, corniculate, and cuneiform cartilages.

Failure of laryngeal recanalization, leaving no airway passage.

Immediate airway management.

Incomplete recanalization of the laryngotracheal tube.

At the anterior glottis between the vocal cords.

Subglottic stenosis.

By direct laryngoscopy.

0–35% obstruction.

36–50% obstruction.

51–75% obstruction.

76–100% obstruction.

Laser or surgical incision and dilation.

Laryngeal reconstruction.

Failure of formation of the tracheoesophageal septum.

Recurrent aspiration, pneumonia, and respiratory infections.

An interarytenoid cleft.

A partial cricoid cleft.

A complete cricoid cleft extending into the cervical trachea.

A laryngotracheal cleft extending into the thoracic trachea.

Operative laryngoscopy and bronchoscopy.

Conservative management.

Open surgical repair.

Laryngomalacia.

Inspiratory stridor.

During the first two weeks of life.

It collapses inward and narrows the airway.

An omega shape.

Flexible laryngoscopy.

When the patient has feeding difficulties or suspected aspiration.

It often resolves spontaneously during the first two years of life.

Supraglottoplasty.

Impaired movement of one or both vocal folds.

Flexible laryngoscopy.

Both vocal folds may fail to open adequately.

Reinnervation, with specialist referral.

Six to twelve months.

Prolonged or repeated intubation.

A cyst arising from the laryngeal saccule that may contain fluid or air.

Endoscopic aspiration and marsupialization.

An abnormally enlarged, air-filled laryngeal saccule.

Endoscopic excision.

Open surgery, sometimes after tracheostomy.

A benign vascular growth that can narrow the subglottic airway.

Within the first 2–6 months of life.

Biphasic stridor.

PHACE syndrome.

Posterior fossa, hemangioma, arterial, cardiac, and eye abnormalities.

Propranolol.

Bradycardia, hypotension, and bronchospasm.

Congenital narrowing of the subglottic larynx.

Biphasic or inspiratory stridor.

The steeple sign.

The Cotton–Myer grading system.

Up to 50% obstruction.

51–70% obstruction.

71–99% obstruction.

No detectable airway lumen.

Dilation or endoscopic laser surgery.

Anterior cricoid split or laryngeal reconstruction.

Complete tracheal rings.

The distal trachea.

Respiratory distress that may not improve with intubation or tracheostomy.

Resection or tracheal reconstruction.

Incomplete separation of the primitive foregut into trachea and esophagus.

Type C: esophageal atresia with a distal fistula.

Frothing, choking, cyanosis, and an inability to pass a feeding tube into the stomach.