Upper Esophageal pH Monitoring of Children With the Bravo pH Capsule

INTRODUCTION Reflux of gastric contents is a common, welldocumented occurrence among adults. Since the early 1980s, gastroesophageal reflux disease (GERD) has been increasingly recognized as a clinical entity among children. Several investigators have noted that approximately half of all newborns have reflux. In the study of Nelson et al., peak incidence of reflux occurred at approximately 4 months of age; approximately 67% of these infants exhibited signs of reflux disease. Prevalence decreased to approximately 5% at 1 year of age. Left untreated, gastroesophageal reflux most commonly results in vomiting (spitting up), abdominal or chest pain, heartburn, arousal from sleep, and regurgitation. Studies have found that up to 75% of patients with symptoms of upper or lower respiratory tract disorders such as asthma, croup, bronchitis, pneumonia, sinusitis, laryngomalacia, and subglottic stenosis have reflux disease. Gastroesophageal reflux may also be associated with more serious complications such as apparent lifethreatening events, isolated bradycardia with irregular respiratory efforts, apnea, hypotension, reduced cerebral blood flow, and sudden infant death syndrome (SIDS). Although reflux is a common occurrence among young children, making a confirmatory diagnosis is difficult in the clinical setting. Pediatric patients are not always cooperative with a 24-hour pH study. Questions about the validity of such studies exist, and the interpretation of the findings can be difficult. TECHNIQUE Children suspected of having gastroesophageal reflux affecting the upper airway have a pH probe or “capsule” put into place in the operating room while undergoing other procedures (predominantly, direct laryngoscopy with bronchoscopy) If there are no plans for surgery, the traditional pH probe is placed through the nose by our colleague. The Bravo capsule technique is used to enhance the diagnosis of reflux, ot to completely change how we diagnose reflux. The delivery system and capsule are manufactured by Medtronic (reference no. 9012B1001, Shoreview, MN). The delivery system is 100 cm long, and the size of the capsule is 26 ! 6.0 ! 6.3 mm (Fig. 1). For an otolaryngologist trained in upper airway management, this technique has been uncomplicated. After securing intubation with an appropriately sized endotracheal tube, the Parsons laryngoscope is reinserted, lifting the larynx forward. This identifies the cricopharyngeal opening to the esophagus. The capsule is placed in the proper position, and the suction device is attached. A small amount of mucosa is gathered and pinned by the delivery device. The capsule is released from the delivery system and remains in place. When detaching the capsule from the delivery system, it is important to turn off the suction machine and also disconnect the suction device from the delivery vehicle to remove any residual suction from the system. This allows a much easier release of the capsule onto the esophageal mucosa without injury. This also aids in the prevention of capsule-related complications. Esophagoscopy has been routinely used to confirm appropriate placement in the upper esophagus, but it is not necessary. Although it would be ideal to have pH measurements from the posterior pharynx to diagnose extraesophageal reflux, this capsule should rest just below the closed cricopharyngeal muscle in the upper esophagus. The cricopharyngeal muscle is composed of striated muscle and is tonically contracted to protect the airway from refluxed esophageal contents (Figs. 2 and 3). While the capsule is in place, the child wears a receiver device, which is approximately the size of a pager. The receiver need not be worn but should remain within 3 feet of the child to ensure proper recording of the data. The child can go home and is allowed to eat normally. No changes in dietary habits are necessary with the capsule. Some procedures require children to be on From the Department of Otolaryngology (M.B., S.B.) and the Departments of Pediatrics (M.B.) and Surgery (J.P.), University of Missouri–Columbia, Columbia, Missouri, U.S.A. Editor’s Note: This Manuscript was accepted for publication November 3, 2003. Send Correspondence to Marcella Bothwell, MD, Department of Otolaryngology and Department of Pediatrics, University Hospital and Clinics, One Hospital Drive, DC027.00, Columbia, MO 65212, U.S.A. Email: bothwellm@health.missouri.edu