Use of an Electromagnetic Device Compared With Chest X-ray to Confirm Nasogastric Feeding Tube Position in Critical Care

Background: Insertion of nasogastric feeding tubes (NGTs) is common in critical care. However, misplacement is frequent and can carry a significant morbidity. Current methods to confirm position of NGTs are not reliable in this setting. We retrospectively compared the position of NGTs using an electromagnetically guided nasogastric tube (e-NGT) with that demonstrated by chest x-ray (CXR), the proportion of lung placements avoided, and the time taken to establish enteral feeding.

Methods: This was a retrospective, observational study undertaken in a tertiary referral, adult intensive care unit between February 2006 and November 2013. Patients were included if they had a radiologically confirmed NGT. All CXRs were independently reviewed by an intensivist to determine position, and a subset of patients had their e-NGT image independently reviewed for quality control. Statistical analysis was in the form of sensitivity and specificity and descriptive where indicated.

Results: In total, 121 NGT placements in 113 patients were analyzed. We found a sensitivity of 98% (95% confidence interval [CI], 93.9%-99.7%) and a specificity of 100% (95% CI, 48.0%-100.0%) when using the e-NGT compared with CXR. In the subset of 51 independently reviewed e-NGT images, 9 lung placements were avoided. The mean (SD) time from e-NGT placement to CXR was 185 (264.4) minutes and to feeding was 404 (77.8) minutes.

Conclusion: When placed by a dedicated team, e-NGT allowed immediate detection of tube misplacement. As such, if used as the sole method for determining NGT position, e-NGTs minimize feeding delay and the need for multiple CXRs with subsequent cost savings.