Isotonic nasogastric tube feedings: do they cause diarrhea?

NG tube feedings in hospitalized patients, whether in a ward or ICU, are considered a common etiology of diarrhea. To evaluate the accuracy of this assumption, 13 hospitalized postoperative patients with head and neck cancer, 11 ICU patients, and five healthy volunteers were given isotonic, low-residue, lactose-free tube feedings starting at 30 kcal/kg.day. There was no prior history of diarrhea in any patient studied. There was a significant difference in both albumin levels and diarrhea incidence in the three groups (analysis of variance, p less than .05). Diarrhea occurred in four of 11 ICU patients while receiving feedings, but not in the healthy volunteers or non-ICU patients. The four patients with diarrhea had an average albumin level of 2.8 g/dl, while the other ICU patients had an average albumin of 2.6 g/dl. We conclude that isotonic NG tube feedings do not cause diarrhea in healthy volunteers or postoperative head and neck cancer patients. However, in some mechanically ventilated ICU patients, this regimen may cause diarrhea even though no risk factors can be clearly identified.