108 - Noninferiority Study Assessing Accuracy of pH Testing for Nasogastric and Orogastric Tube Placement vs Radiography

Publication Number: 3103.108

Purnahamsi Desai, New York University Grossman School of Medicine, New York, NY, United States; Samantha Alessi, NewYork-Presbyterian Komansky Children’s Hospital, New York, NY, United States; Lydia Carson, Hassenfeld Children's Hospital at NYU Langone, Madison, NJ, United States; melissa O'Meara, Hassenfeld Children's Hospital at NYU Langone, YONKERS, NY, United States; Hannah Street, Mount Sinai Hospital, Brooklyn, NY, United States; Sourabh Verma, Hassenfeld Children's Hospital at NYU Langone, New York, NY, United States

Background: Though enteral feeding tubes are commonly utilized in neonatal intensive care units (NICUs), there are risks associated with malpositioning, including feeding intolerance, aspiration, tracheal or pulmonary perforation, pneumothorax, pneumonitis, pneumonia, or death. Historically gastric tube placement has been seen as a benign procedure with no confirmation of placement beyond auscultation of air in the stomach and no standard recommendation for verification of placement.

In 2018 NOVEL project recommended consensus guidelines endorsed by ASPEN1. Abdominal radiography is the current gold standard in the United States, however this is costly as well as the concern for repetitive radiation exposure in neonates. Utilizing gastric aspirate samples following tube placement with pH testing using a cutoff of ≤5 has been shown to be effective, with limited studies demonstrating efficacy in neonates3. There have been no studies evaluating direct comparison of pH testing with radiography.

Objective: The primary study objective was to show that pH testing to confirm placement of gastric tubes is non-inferior to radiography.

Design/Methods: We conducted an IRB approved single-center retrospective cohort study inclusive of all infants admitted to the New York University Langone Health (NYULH) NICU between October 1, 2023 and March 31, 2024 where gastric tube placement was indicated. Exclusion criteria were infants with an esophageal anomaly, post-pyloric feeding tubes, or suction tubes placed for gastric decompression. Gastric tube placement was verified by Nose-Earlobe-Midway xiphoid and Umbilicus (NEMU) method and both pH testing of gastric aspirates and radiography as part of standard care. Appropriate tube placement verified by pH testing was defined as a pH result ≤5. Results of both verification methods as well as relevant patient demographic information were collected from EPIC electronic health record.

Results: Of 202 gastric tube placements confirmed by NEMU that were evaluated, 194 had pH≤5 and confirmed appropriate placement on radiography. 2 had pH ≤5 with malposition noted on radiography, and 6 had pH≥5 with appropriate placement in stomach. There were no subjects that had pH≥5 with confirmed malposition of tube. This yielded a pH testing sensitivity of 97% and a positive predictive value of 99%.

Conclusion(s): The combination of NEMU and testing of pH for confirmation of gastric tube placement is an accurate, cost effective, and safe alternative to radiography and preferred to the historic method of auscultation.