Feasibility of volatile detection for naso-gastric tube placement

Yorkshire & HumberGeneric Health Relevance, Injuries and Accidents
Start Date: 1 Jan 2015 End Date: 9 May 2016

Project description

Naso-gastric (NG) tubes (a tube passed through a patient's nostril into their food pipe and then stomach, secured to the patient's cheek with tape) are widely used in the NHS for adult and child patients to provide enteral feeds or medicines for patients who cannot swallow or tolerate feeds by mouth, or patients requiring intensive care/surgery. There are patient safety concerns if a NG tube becomes misplaced into the patient's lung during insertion or moves out of the patient's stomach at a later stage, which can result in serious consequences for the patient or even death if feeding occurs through a misplaced NG tube. The current procedure for testing correct placement of an NG tube relies upon getting gastric aspirate up an NG tube for testing with pH paper, but only 65% success rates are reported for getting aspirate. Then X-rays are used to verify NG tube position; X-rays are costly and inconvenient for patients, and also subject to misinterpretation. Something better is needed. This research aims to test a proof of concept for checking the correct position of an NG tube, by testing volatile organic chemicals and concentration of gases from breath and gastric aspirate samples, creating 'smell fingerprints'. The researchers need to obtain gastric aspirate and breath samples from 50 to 60 patients undergoing a routine hospital gastroscopy procedure.

Expected outcomes

Analysis of these biological samples using chemical sensor technology may enable the team to apply this concept to the development of a new portable bedside device that healthcare staff and carers could use to test correct placement of an NG tube. The research will also include a focus group meeting with healthcare staff to aid our understanding of the features/characteristics required for a new NG tube testing device. 

Dr Angela Grange