Predicting the insertion length for gastric tube placement in neonates

To compare error rates of three existing methods of predicting the gastric tube insertion length in a group of neonates <1 month corrected age: age-related, height-based (ARHB); direct distance nose-ear-xiphoid (NEX); and direct distance nose-ear-mid-umbilicus (NEMU).

Randomized controlled trial.

Five neonatal care units in a large midwestern city.

One hundred and seventy-three hospitalized neonates.

Neonates were randomly assigned to one of three groups: ARHB, NEX, or NEMU. For primary analysis, only tubes placed too high with the tube tip in the esophagus or at the gastroesophageal junction were considered to be misplaced. For secondary analysis, a stricter definition was used, and low placements (pylorus or duodenum) were also considered to be misplaced. All radiographs were blinded and read by a pediatric radiologist.

For the primary analysis, the differences in percentages of correctly placed tubes among the three methods was statistically significant (χ(2) =34.45; p<.0001), with NEMU and ARHB more accurate than NEX (NEMU χ(2) =18.59, p<.0001; ARHB χ(2) =21.34, p<.0001). Using the stricter definition for placement, ARHB was not significantly different from NEX (p=.0615). A new ARHB equation was developed specific for neonates <1 month corrected age.

Direct distance nose-ear-xiphoid should no longer be used as an nasogastric/orogastric (NG/OG) tube insertion-length predictor in neonates. Either NEMU for NG/OG tubes or the new ARHB equation for NG tubes should be used.