Title: Location-Indicating Naso-gastric Tube (NGT)
Funder: Department of Health (England)

Abstract: Background Nasogastric tubes (NGT) are the preferred means of feeding critically ill patients of all ages including babies and also are widely used in gastric decompression prior to emergency surgery to reduce aspiration risk. Verification of correct placement can be extremely difficult and must be undertaken after insertion and before each feed. Misplacement is common especially in children (reported in up 21% of patients1). Misplacement in the oesophagus may cause intolerance of feeds and NGT erroneously placed in the respiratory tract can cause serious complications and death. 210 incidents due to misplaced NGT were reported between 2005 and 2008 2 1. Ellett et al (2005) Gastric Tube Placement in Young Children, Clin. Nurs Res., 14, 238-252 2. NPSA (2008) Incidents related to NGT, www.npsa.nhs.uk Aims To fulfil an unmet clinical need by developing an effective, sensitive and reliable NGT which self-indicates its position thus ensuring greater safety with concomitant reduced distress both to patients and carers. The new Hull NGT (HNGT) can provide an indication of position when required whilst in place which will minimise the risks and complications associated with current methods of verifying NGT placement. These currently depend upon pH testing of stomach aspirate (recommended by the NPSA). Because it will be safer, easier and quicker to use than currently available techniques, the HNGT will also be cost effective. Overall the developed, affordable, HNGT will benefit the great numbers of patients who require nasogastric nutrition and gastric decompression in this and other countries. Plan of Investigation Hand-made prototypes have demonstrated the feasibility of a chemical based self-indication system. The HNGT utilises amperometric pH detection combined with a redox reagent to provide improved certainty of detection of NGT location over conventional pH measurement. The chemistry will be refined until suitable for commercial manufacture; certainty of safety in human use will be an ever-present consideration. Tube substrates will be identified and tested alone and also integrated and optimised with the chemical system. Testing will include an ex vivo analysis of resected gastric mucosa obtained from patients undergoing gastrectomy for malignancy and other diseases. The projected end-point is a pre-production medical device, pilot-trialled, CE marked and ready for commercialisation. Potential Impact Adoption of the HNGT will reduce levels of patient discomfort caused by repeated attempts at correct placement, as well as potential distress and harm associated with misplacement of tubes.Health professionals and carers using the HNGT will feel greatly increased confidence that nasogastric tubes are correctly placed prior to initiation of therapy enabling increased involvement of lay carers in the procedure.For the NHS and other health care providers, the impact of the HNGT will be that the costs of dealing with the complications, mortality and morbidity associated with misplaced NG and other tubes will be avoided and more NG feeding can take place in the community. Improved levels of patient care, cost savings and litigation avoidance will together provide an important beneficial impact.


Research activity codes: 6.3 MEDICAL DEVICES;5.3 MEDICAL DEVICES
Health categories: GENERIC HEALTH RELEVANCE