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In managing upper-airway problems in neonates, infants and children, it is important to understand the differences between the anatomy and physiology of their respiratory system and that of adults. It is obvious that the neonate’s airway is considerably smaller than that of an adult. The average diameter of the subglottis in a full-term baby is around 3.5 mm, that of an adolescent around 7 mm and in an adult around 10–14 mm. The impact of a reduction in the diameter of the airway upon its cross-sectional area (Fig. 21.1) is increased by the direct relationship of this area to the square of the radius (cross-sectional area = πr). The clinical implication of this is further magnified by the inverse relation of resistance of flow to the radius4 in a tubular structure, as defined by Poiseuille’s law, originally describing laminar flow of a fluid in a cylindrical tube (resistance αl×∂/πr, where l is the length of the tube, r is the radius and ∂ is the density of the gas). Figure 21.2 illustrates the dramatic differences in the impact of 1 mm of mucosal oedema in an adult, a child of 6–8 years of age and a neonate. An adult will barely notice the change, a child will have significant difficulty, and for a neonate, it may have a fatal outcome.

The exact incidence of congenital abnormalities of the airway is uncertain, but a figure has been quoted for congenital laryngeal anomalies of between 1:10,000 and 1:50,000 births (Van den Broek and Brinkman 1979). Furthermore, some of these children will have more than one anomaly in the airway (Shugar and Healey 1980).

Laryngitis is an inflammatory process affecting the larynx. Acute infective laryngitis is the most frequent form of laryngitis seen in clinical practice in the primary care setting. In children it is usually associated with an upper respiratory tract infection. The vast majority of cases are of viral aetiology, the usual causative agents being rhinovirus, adenovirus, parainfluenza virus or respiratory syncytial virus. Rarely nowadays, since the introduction of widespread vaccination, laryngitis may also occur during the course of measles and infection. Most cases are relatively benign and self-limiting, resolving spontaneously with only supportive treatment necessary. Occasionally, a child is referred with persistent hoarseness after a typical sounding episode of laryngitis, and then flexible laryngoscopy is required to exclude any other pathology. In the absence of such pathology, the usual finding is of some persistent oedema of the laryngeal mucosa, particularly of the vocal cords. This will generally settle over time.

Within the anatomic confines of the larynx, a variety of pathologies may compromise air flow, causing airway obstruction. This chapter describes two such anomalies – laryngeal webs and subglottic hemangiomas. This chapter includes a description of these disorders followed by a synopsis of diagnostic guidelines and current management strategies.

The older term “subglottic stenosis” has largely been replaced by laryngotracheal stenosis (LTS) to highlight the glottic component of the stenosis, which is particularly important when considering resection.

The vast majority of paediatric tracheal stenosis is congenital and relates to the presence of complete tracheal rings, so that the entire circumference of the airway is cartilaginous (Fig. 26.1).

Tracheomalacia is a condition that is characterised by weakness of the cartilages supporting the trachea. It is usually suspected when endoscopy shows tracheal collapse with greater than 50% tracheal obstruction during expiration (Benjamin 1984). Two anomalies account for these findings: weakness of the tracheal wall resulting from reduction of the ratio between the cartilaginous rings and posterior transverse muscle, and hypotonia of the posterior transverse muscle, resulting in forward ballooning, especially during expiration. Tracheomalacia can be classified as primary and secondary. In secondary tracheomalacia, lesions are usually limited to one segment, whereas primary tracheomalacia (tracheal dyskinesia) extends for the entire length of the airway (see Table 27.1).

In this chapter, the following are discussed: the changing indications for tracheotomy, the changing nature of the population of children with a tracheotomy, alternatives to a tracheotomy, the surgical technique and its complications, home care of a child with a tracheostomy, and how to decannulate a child.

Recurrent respiratory papillomatosis (RRP) is a disease of viral origin that occurs in both pediatric and adult populations. Its symptoms, primarily hoarseness and manifestations of airway obstruction, are due to human papilloma virus (HPV) infection of the laryngotracheal airway and the development of exophytic growths that alter airflow. RRP is the most common benign laryngeal tumor to occur in children and the second most frequent cause (after vocal cord nodules) of chronic hoarseness (Wiatrak et al. 2004). RRP has no known cure, and it can cause significant morbidity.

The upper aerodigestive tract, which consists of the nose, mouth, pharynx, larynx and oesophagus, allows for the passage of air and food. These structures form one of the most complex neuromuscular systems of the body, providing the structural and dynamic components for swallowing, respiration and speech.