Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + INTRINSIC ABNORMALITIES OF THE AIRWAY Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ Intrinsic abnormalities of the airway that cause partial obstruction of the airway fall into this category. Examples include laryngomalacia, vocal cord paralysis, subglottic web, and hemangioma. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ Lesions result in partial obstruction of the airway and cause stridor and respiratory distress of varying severity. ++ Laryngomalacia is due to delayed development of the supraglottic pharynx. Congenital vocal cord paralysis can be congenital or acquired (birth trauma, patent ductus arteriosus ligation) and unilateral or bilateral. Subglottic web is a congenital short-segment obstruction that may be partial or complete. Hemangioma can occur below the glottis, engorge, and obstruct with agitation. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ This can vary from mild respiratory stridor to complete airway obstruction depending on pathology. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ The diagnosis is established by airway endoscopy with careful visual inspection. + V. MANAGEMENT Download Section PDF Listen +++ ++ Management is individualized. Some problems, such as laryngomalacia, will be outgrown and require only supportive care. Other lesions, such as subglottic webs and hemangiomas, may be amenable to endoscopic resection or laser therapy. + CHOANAL ATRESIA Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ Choanal atresia is a congenital blockage of the posterior nares caused by a persistence of a bony septum (90%) or a soft tissue membrane (10%). + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ True choanal atresia is complete and bilateral, and it is one cause of respiratory distress immediately after delivery. Neonates are obligate nose breathers and do not automatically breathe through the mouth. Unilateral defects may be well tolerated and often go unnoticed. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Respiratory distress resulting from partial or total upper airway obstruction is the mode of presentation. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ Diagnosis is based on the inability to pass a catheter into the nasopharynx via either side of the nose. + V. MANAGEMENT Download Section PDF Listen +++ ++ Making the baby cry will initiate mouth breathing and temporarily improves the respiratory status. Insertion of an oral airway maintains the ability to breathe until the atresia is surgically corrected. Definitive management requires resection of the soft tissue or bony septum in the nasopharynx. + PIERRE ROBIN SEQUENCE Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ This anomaly consists of mandibular hypoplasia (micrognathia) in association with cleft palate. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ Airway obstruction is produced by posterior displacement of the tongue associated with the small size of the mandible. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Severity of symptoms varies, but most infants manifest a high degree of partial upper airway obstruction + IV. MANAGEMENT Download Section PDF Listen +++ ++ Infants with mild involvement can be cared for in the prone position and fed through a special Breck nipple. Over the next few weeks to months, the mandible grows and the degree of airway obstruction subsides. More severe cases require nasopharyngeal tubes, mandibular distraction, or other procedures to hold the tongue in an anterior position. Tracheostomy is generally a last resort. + LARYNGOTRACHEAL ESOPHAGEAL CLEFT Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ A rare congenital anomaly in which there is an incomplete separation of the larynx (and sometimes the trachea) from the esophagus, resulting in a common channel of esophagus and airway. This communication may be short or may extend almost the entire length of the trachea. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ The persistent communication between the larynx (and occasionally a significant portion of the trachea) and the esophagus results in recurring symptoms of aspiration and respiratory distress with feeding. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Respiratory distress during feeding is the presenting symptom. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ Contrast swallow may suggest the anomaly, but endoscopy is essential to establish the diagnosis and delineate the extent of the defect. + V. MANAGEMENT Download Section PDF Listen +++ ++ Laryngotracheal esophageal cleft is treated by surgical correction, which is difficult and often unsuccessful. + VASCULAR RING Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ A vascular ring denotes a variety of anomalies of the aortic arch and its branches that create a “ring” of vessels around the trachea and esophagus. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ Partial obstruction of the trachea, the esophagus, or both may result from extrinsic compression by the encircling ring of vessels. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Dysphagia and/or stridor (respiratory insufficiency) are the modes of presentation. Airway compromise is rarely severe and usually presents as stridor. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ Diagnosis is by barium swallow, which identifies extrinsic compression of the esophagus in the region of the aortic arch. Computed tomography (CT) and magnetic resonance imaging (MRI) are useful to further define the anatomy. + V. MANAGEMENT Download Section PDF Listen +++ ++ Management consists of surgically dividing a portion of the constricting vascular ring. The surgical plan must be tailored to the specific type of anomaly. + TYPE E (OR H-TYPE) TRACHEOESOPHAGEAL FISTULA Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ This anomaly is an uncommon type of tracheoesophageal fistula (TEF), making up 5% of cases. Esophageal continuity is intact, but there is a fistulous communication between the posterior trachea and the anterior esophagus. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ When the fistula is small, “silent” aspiration with resulting pneumonitis occurs during feedings. If the fistula is unusually large, coughing and choking may accompany each feeding. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Symptoms, as noted previously, depend on the size of the fistula. This TEF subtype frequently escapes diagnosis in the newborn period. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ Barium swallow is the initial diagnostic study, but it sometimes fails to identify the fistula. The test's sensitivity can be increased with a “pull back” upper gastrointestinal (UGI) series. Here, a nasogastric tube placed in the distal esophagus is pulled out slowly while instilling water-soluble contrast. The most accurate procedure is bronchoscopy (often combined with esophagoscopy). This should allow discovery and perhaps cannulation of the fistula. + V. MANAGEMENT Download Section PDF Listen +++ ++ Surgical correction is required. The approach (via the neck or chest) is determined by location of the fistula. + CONGENITAL LOBAR EMPHYSEMA Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ Lobar emphysema denotes hyperexpansion of the air spaces in a segment or lobe of the lung. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ Inspired air is trapped in an enclosed space. As the entrapped air expands, the normal lung is increasingly compressed. Cystic problems are more common in the upper lobes. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Small cysts may cause few or no symptoms and are readily seen on radiograph. Giant cysts may cause significant respiratory distress, with mediastinal shift and compromise of the contralateral lung. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ Usually, the cysts are easily seen on plain chest radiographs. However, the radiologic findings may be confused with tension pneumothorax. Chest CT is often useful. + V. MANAGEMENT Download Section PDF Listen +++ ++ Therapeutic options include observation for small asymptomatic cysts, repositioning of the endotracheal tube to selectively ventilate the uninvolved lung for 6–12 hours, bronchoscopy for endobronchial lavage, and operative resection of the cyst with or without the lobe from which it arises. + CYSTIC ADENOMATOID MALFORMATION Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ The term cystic adenomatoid malformation (CAM) encompasses a spectrum of congenital pulmonary malformations involving varying degrees of cyst formation. They communicate with the normal tracheobronchial tree. There are 3 types (I, II, and III) depending on the size of the cysts within the malformation. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ Severity of symptoms is related to the amount of lung involved and particularly to the degree to which the normal ipsilateral and contralateral lung is compressed. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Signs of respiratory insufficiency such as tachypnea and cyanosis are modes of presentation. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ The characteristic pattern on chest radiograph is multiple discrete air bubbles, occasionally with air-fluid levels, involving a region of the lung. The radiographic appearance can mimic that of congenital diaphragmatic hernia (CDH). + V. MANAGEMENT Download Section PDF Listen +++ ++ Treatment is surgical resection of the involved lobe of lung, allowing reexpansion of compressed normal pulmonary tissue. If small and without symptoms, the surgical management can wait until the infant is several months of age. + PULMONARY SEQUESTRATION Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ Pulmonary sequestration is masses of abnormal tissue with aberrant blood supply arising from a systemic and not a pulmonary source. They may be intralobar or extralobar. Intralobar sequestrations have abnormal connections to the tracheobronchial tree. Extralobar sequestrations have separate pleura and no connections to the tracheobronchial tree. + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ Sequestrations are usually not recognized in the neonate. Intralobar sequestrations are found after frequent recurrent infections. Extralobar sequestrations are usually not associated with infections. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Lung mass found with or without frequent recurrent infections. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ Diagnosis is by chest radiograph and CT scan. + V. MANAGEMENT Download Section PDF Listen +++ ++ Surgical resection is warranted. Aberrant blood supply may originate from below the diaphragm. + CONGENITAL DIAPHRAGMATIC HERNIA Download Section PDF Listen +++ + I. DEFINITION Download Section PDF Listen +++ ++ A patent pleuroperitoneal canal through the foramen of Bochdalek is the most common defect in congenital diaphragmatic hernia (CDH) (95%). A central anterior defect of the diaphragm (Morgagni hernia) is less common and usually not associated with lung hypoplasia + II. PATHOPHYSIOLOGY Download Section PDF Listen +++ ++ Prenatal. Abnormal communication between the peritoneal and pleural cavities allows herniation of intestine into the pleural space as the developing gastrointestinal (GI) tract returns from its extracoelomic phase at 10–12 weeks' gestation. Depending on the degree of pulmonary compression by herniated intestine, there may be marked diminution of bronchial branching, limited multiplication of alveoli, and persistence of muscular hypertrophy in pulmonary arterioles. These lung abnormalities are most notable on the same side as the CDH (usually the left); they are also present to some degree in the contralateral lung. Postnatal. After delivery, the anatomic anomaly may contribute to the following pathologic conditions: Pulmonary parenchymal insufficiency. Infants with CDH have an abnormally small functional lung mass. Some have so few conducting air passages and developed alveoli—a condition known as pulmonary parenchymal insufficiency—that survival is unlikely. Pulmonary hypertension. Infants with CDH are predisposed to persistent pulmonary hypertension of the newborn (PPHN), also known as persistent fetal circulation. In this condition, blood is shunted away from the lungs through the foramen ovale and patent ductus arteriosus (PDA). Shunting promotes acidosis and hypoxia, both of which are potent stimuli to additional pulmonary vasoconstriction. Thus, a vicious cycle of clinical deterioration is established. + III. CLINICAL PRESENTATION Download Section PDF Listen +++ ++ Most infants with CDH exhibit significant respiratory distress within the first few hours of life. + IV. DIAGNOSIS Download Section PDF Listen +++ ++ Prenatal diagnosis can reliably be made by ultrasonography. Delivery should occur in a neonatal center with full resuscitation capability, including extracorporeal life support/extracorporeal membrane oxygenation (ECLS/ECMO). Afflicted infants tend to have scaphoid abdomens because a paucity of the GI tract is located in the abdomen. Auscultation reveals diminished breath sounds on the affected side. Diagnosis is established by a chest radiograph that reveals a bowel gas pattern in one hemithorax, with shift of mediastinal structures to the other side, and compromise of the contralateral lung + V. MANAGEMENT Download Section PDF Listen +++ ++ Indwelling arterial catheter. Blood gas levels should be monitored by an arterial catheter. Supportive care. Intubation with positive-pressure ventilation should be initiated immediately. CDH lungs can be surfactant deficient, and replacement therapy may be helpful. Several different strategies for appropriate respiratory and metabolic support have been described. These include permissive hypercapnia with conventional ventilation, oscillator ventilation, and/or the addition of inhaled nitric oxide. All these therapies are aimed at providing maximal pulmonary vasodilatation with minimal secondary lung injury due to barotrauma. Nasogastric tube. A nasogastric tube should be placed to lessen gaseous distention of the stomach and intestine. Care must be taken to make sure the tube remains functional and does not clog. Surgical correction. This is done by reduction of intrathoracic intestine and closure of the diaphragmatic defect. Surgical intervention is an essential element of treatment, but it is not the key to survival. Most authorities favor a delayed approach, allowing the newborn to stabilize its hyperreactive pulmonary vascular bed and to improve pulmonary compliance. If indicated, ECMO/ECLS can be instituted, and repair of the hernia defect performed immediately after stabilization on ECMO/ECLS, when the infant is ready to wean from ECMO/ECLS, or after successful ECMO/ECLS decannulation. Extracorporeal life support/extracorporeal membrane oxygenation (ECLS/ECMO). Used in the treatment of neonates with severe respiratory failure. Exposure of venous blood to the ECMO/ECLS circuit allows correction of Po2 and Pco2 abnormalities as the lungs recover from the trauma associated with positive-pressure ventilation (see Chapter 18). + VI. PROGNOSIS Download Section PDF Listen +++ ++ Mortality rates for infants with CDH are still in the range of 50%. This high rate has prompted a search for other modes of treatment in addition to the expensive, labor-intensive modality ECLS. ++ Fetal surgery. This has been performed successfully on a case study basis, with the idea that in utero intervention will lessen the risk for development of pulmonary hypoplasia, which may be incompatible with life after delivery. However, trials of fetal tracheal occlusion and complete fetal correction have been abandoned due to high mortality. Medications. Another major area of research is the attempt to develop a pharmacologic agent to decrease pulmonary vascular resistance selectively. To date, early promising data on inhaled nitric oxide have been tempered with the realization that it does not reverse pulmonary hypertension. Sildenafil (0.5–1 mg/kg every 6 hours) is reported to lower pulmonary hypertension in neonates with PPHN. + SELECTED REFERENCES Download Section PDF Listen +++ + +Dimmitt RA, Moss RL, Rhine WD, Benitz WE, Henry MC, Vanmeurs KP. Venoarterial versus venovenous extracorporeal membrane oxygenation in congenital diaphragmatic hernia: the extracorporeal life support organization registry, 1990–1999. J Pediatr Surg. 2001;36:1199.CrossRef [PubMed: 11479856] + +Greenholz SK. Congenital diaphragmatic hernia: an overview. Semin Pediatr Surg. 1996;5:216. [PubMed: 8936650] + +Grosfeld JL, O'Neill JA, Coran AG, Fonkalsrud E, eds. Pediatric Surgery. 6th ed. St. Louis, MO: Mosby-Year Book; 2006.+ +Harting MT, Lally KP. Surgical management of neonates with congenital diaphragmatic hernia. Semin Pediatr Surg. 2007;16(2):109–114.CrossRef [PubMed: 17462563] + +Logan JW, Rice HE, Goldberg RN, Cotten CM. Congenital diaphragmatic hernia: a systematic review and summary of best-evidence practice strategies. J Perinatol. 2007;27(9): 535–549.CrossRef [PubMed: 17637787] + +Nuchtern JG, Harberg FJ. Congenital lung cysts. Semin Pediatr Surg. 1994;3:233. [PubMed: 7850363] + +O'Neill JA, Grosfeld J, Fonkalsrud E, Coran AG, Caldamone AA, eds. Principles of Pediatric Surgery. 2nd ed. St. Louis, MO: Mosby; 2004.+ +Skinner SC, Hirschl RB, Bartlett RH. Extracorporeal life support. Semin Pediatr Surg. 2006;15(4):242–250.CrossRef [PubMed: 17055954] + +Wung JT, Sahni R, Moffitt ST, Lipsitz E, Stolar CJ. Congenital diaphragmatic hernia: survival treated with very delayed surgery, spontaneous respiration and no chest tube. J Pediatr Surg. 1995;30:406.CrossRef [PubMed: 7760230]