same ability to use these same types of ventilating rigid bronchoscopes in pediatrics, numerous differences need to be recognized. The presence of a smaller airway diameter limits the size of endotracheal appliances (rigid bronchoscope or endotracheal tube) that can be introduced, affects the ability to utilize many instruments, and increases potential risk of complications from excessive airway pressures [12]. Endotracheal tube size is often estimated by age or weight in pediatrics (Table 38.1), but can also be done by selecting an outer diameter similar in size to the child’s fth nger [15].

Advanced Diagnostic Procedures

Endobronchial Ultrasound

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) was initially introduced to the adult pulmonology community as a way to increase diagnostic yield in lung cancer. It has since experienced widespread acceptance and popularity, with a recent PubMed search of over 4000 articles. However, there remains a paucity of literature related to utilization in pediatrics.

The convex probe endobronchial ultrasound (EBUS) puncturescope (Fig. 38.1) was introduced in early 2000 [16] and since has revolutionized the care of adult patients with mediastinal and hilar lymphadenopathy, especially regarding the care of patients with suspected lung cancer. These bronchoscopes are generally designed for examination of the more central structures, often medi-

astinal and hilar lymphadenopathy, but can also access centrally located lesions [17]. Currently, the main limitation for use of the EBUS puncturescope within the pediatric population remains the large scope diameter, with all possessing an outer diameter of greater than 6 mm. However, there is ongoing development of a smaller diameter EBUS scope that may lead to greater usability within the pediatric population [18, 19].

The adult literature suggests widespread adoption of Endobronchial Ultrasound - Transbronchial NeedleAspiration (EBUS-TBNA) and in most high-volume institutions that provide multidisciplinary care to patients with thoracic malignancies, EBUS-­TBNA has often replaced mediastinoscopy as an initial diagnostic test [20–22]. Attractive features to EBUS-guided procedures include the potential for decreased cost, complications, and hospital resource utilization.

The pediatric literature remains scant; however, over time, there have been more publications, and the data suggest the procedure remains feasible, even in small children and infants. Initial case reports described EBUS in children 6 [23] and 13 [24] years of age. Following this, a multicenter study identi ed 21 pediatric patients safely undergoing EBUS with ages ranging from 18 months to 18 years [25]. Additional larger cohorts have also demonstrated that both EBUS-­TBNA (bronchoscope) and endoscopic ultrasound guidedne-needle aspiration using the EBUS scope (EUS-B-FNA) (gastroscope) are safe with good diagnostic yield [26, 27]. Additionally, a larger systematic review of 173 patients suggested both major and minor complications were minimal at 0.3% and 3.5%, respectively [28].

Fig. 38.1  Convex probe endobronchial ultrasound (CP-EBUS) puncturescope. (a) Photograph of CP-EBUS puncturescope tip from within the trachea. The ultrasound probe is located at the distal tip of the scope, whereas the working channel is in the immediate near eld view. (b) Ultrasound image of a transbronchial needle aspiration

(TBNA) needle (red arrow) within a lymph node. The superior vena cava is also identi ed (green lightning bolt). (c) View of EBUS puncturescope during TBNA, with needle (blue arrow) coming through working channel and buried in 4R lymph node

Virtual Navigational Bronchoscopy

Navigational bronchoscopy is a rapidly expanding tool within the adult population. This technology remains feasible for use in pediatrics as it often has no speci c requirements or needs that would limit use to the adult population only. However, the use of these technologies does require the use of specially formatted computed tomography scans (Fig. 38.2). One small study using intraoperative electromagnetic navigational bronchoscopy in the pediatric population demonstrated high diagnostic yield (seven of eight biopsies changing disease management) [29]. Virtual bronchoscopy has also been utilized as a comparison to fexible bronchoscopy (FB) in the diagnosis of pediatric tracheobronchomalacia. It remains unclear if virtual bronchoscopy would replace fexible bronchoscopy; however, it appears that virtual bronchoscopy might be a viable option with a speci city of greater than 87% and 95% for tracheomalacia and bronchomalacia detection, respectively [30].

Cryobiopsy

Flexible bronchoscopic cryobiopsy is a recent innovation that has been used in the diagnosis of

interstitial lung disease and endobronchial tumors in the adult population. Cryobiopsy allows for larger biopsy sample collection when compared to conventional techniques, and without the crush artifact that comes with forceps biopsy [31, 32]. Much like other IP advances made in the adult population, cryobiopsy has slowly been introduced to pediatric populations. Due to recent improvements in size of available bronchoscopes and cryoprobes, cryobiopsy has now been used in the diagnosis of an endobronchial tumor [33] and interstitial lung disease in the pediatric population [34]. As this technology and technique continues to become more widespread in the IP community, we can only imagine similar advances will continue in the pediatric population.

Additionally, a common indication for bronchoscopy in children remains foreign body aspiration (Fig. 38.3). The cryoprobe can provide an additional tool in the armamentarium of foreign body retrieval tools. Some proposed bene ts of foreign body cryoprobe extraction techniques include removal of the original object and any broken off portions en masse, as well as fragmenting or slipping through a traditional forceps [35]. More recent studies have been performed with larger cohorts and with similar success (over 85% of FB in the rst pass, with over 90% in two passes) [36].