A cost utility analysis of the clinical algorithm for nasogastric tube placement confirmation in adult hospital patients

Aim: The aim of this study was to evaluate the effectiveness of pH paper testing of aspirate and chest x-ray for determining nasogastric tube (NGT) placement in terms of cost and patient outcome.

Background: Nasogastric tubes are frequently used in clinical practice, however during insertion the practitioner is blinded as to the precise final location. Despite robust checking procedures, recognized patient morbidity and mortality associated with this procedure have resulted in national safety alerts prompting the revision of all NGT care clinical guidelines.

Design: Cost utility analysis using economic modelling.

Methods: A decision tree was built and populated with effectiveness data gathered from a systematic search of the extant literature. Specificity, pooled sensitivity and event probabilities were calculated using statistical software. Patient outcome was measured in terms of quality of life. Health state utilities were gathered from a sample (n = 23) of adult surgical patients using a recognized instrument. Cost data were gathered using published sources. The study adopted a third party payer perspective in a Scottish context and was completed in June 2013.

Results: The results confirm that the current UK algorithm advocated by the National Patient Safety Agency appears to offer the most cost effective approach to NGT confirmation in terms of cost and patient outcome. Sensitivity analyses indicate that these findings may be significantly altered by tube aspiration success and the rates of chest x-ray interpretation errors.

Conclusion: The results confirm current UK recommendations and have wider policy implications for those areas, whereby chest x-ray is recommended as the first and only acceptable confirmation approach.