A Validation Study of the Dx-pH Probe in Children for the Detection of Extra-oesophageal Reflux

"The Dx-pH Measurement system (Dx-pH; Respiratory Technology Corp., San Diego, CA) is a sensitive and minimally invasive transnasal device for detection of aerosolized extra-oesophageal acid reflux in the posterior oropharynx.~The sterile single use Dx-pH catheter will be passed trans-nasally into the same nostril as the same nostril as the other catheter. The internal pH value of the oesophagus is then continuously measured and recorded onto a small ambulatory device. The 2 catheters are connected to the ambulatory recording devices and recording commences. The duration of the investigation is 24 hours."

A saliva sample of 0.5-1 ml will then be taken for pepsin assay (Peptest). The saliva sample will be drawn into a micro-centrifuge tube (0.5ml) and centrifuged. 80 microlitres is taken from the supernatant layer, vortex mixed, then applied to the assay test strip. The result is obtained after 15 minutes. The saliva sample will then be securely disposed.

A validated 7 domain GORD symptom questionnaire (GSQ-YC) to quantify the GORD related symptoms their child suffers with is to be completed prior to any intervention.