The Subdiaphragmatic Angle Of The Gastric Tube In Neonates - A Potential Predictor For Perforations?

Background: Traumatic subdiaphramatic perforation of esophagus or stomach in neonates represents a rare clinical complication following the insertion of a gastric tube and is associated with high morbidity and mortality. The aim of the present study was to evaluate whether the angle of the gastric tube depicted on a plain radiograph may serve as a diagnostic tool to predict subdiaphragmatic traumatic (or iatrogenic) perforation.

Patients and methods: Thoraco-abdominal radiographs of 128 preterm and term neonates without perforation and 15 neonates with perforation of the esophagogastric junction or the stomach were retrospectively analysed.

Results: The angle of the gastric tube increases with postnatal age (p=0.0380). In the control group, the angle of the gastric tube varied between 13° and 48° (median: 31°), whereas the values ranged from -31° to 42° (median: 11°) in neonates with subdiaphragmatic perforation. Perforation should thus be suspected in cases with an angle of<20° (sensitivity: 93.3%; specificity: 91.4%). Moreover, an unusual localization of the tip beyond the gastric bubble is highly indicative of perforation.

Discussion: The present study emphasizes the importance of verifying the correct course of an inserted gastric tube.

Conclusions: In daily clinical practice, an angle of<20° should be followed by thorough physical examination, abdominal ultrasound and if applicable contrast medium examinations to exclude perforation.