This study aims at understanding the rationale behind performing prefeed gastric aspirations in preterm infants, how nurses and physicians interpret the gastric aspiration and variations between them, and illuminating potential barriers for omitting routine prefeed aspiration. Nurses and physicians from all Danish neonatal intensive care units completed a questionnaire. Of 682 participants, the majority (94%) indicated that they routinely performed prefeed aspiration, primarily to check the feeding tube placement (nurses: 88%, physicians: 46%). Nurses feared necrotizing enterocolitis when observing a large gastric residual (GR) volume (31%) and green-stained GR (63%). Fewer nurses relative to physicians had "no worries" related to large volumes (15% vs 34%) or green-stained GR (14% vs 24%, both P <.01). More nurses than physicians intended to pause enteral feeding when observing green-stained GR (31% vs 16%, P <.01) and more nurses were concerned of completely omitting routine gastric aspirations (90% vs 46%, P <.05). The rationale behind the clinical use of GR volume and color as markers of necrotizing enterocolitis and feeding intolerance differs markedly between nurses and physicians in Denmark. If routine prefeed gastric aspiration should be omitted, special focus on information about early signs of necrotizing enterocolitis and methods to check tube placement is needed.