Background: We aimed to determine the incidence of enteral feed intolerance and factors associated with intolerance and to assess the influence of intolerance on nutrition and clinical outcomes.

Methods: We conducted a retrospective analysis of data from an international observational cohort study of nutrition practices among 167 intensive care units (ICUs). Data were collected on nutrition adequacy, ventilator-free days (VFDs), ICU stay, and 60-day mortality. Intolerance was defined as interruption of enteral nutrition (EN) due to gastrointestinal (GI) reasons (large gastric residuals, abdominal distension, emesis, diarrhea, or subjective discomfort). Logistic regression was used to determine risk factors for intolerance and their clinical significance. A sensitivity analysis restricted to sites specifying a gastric residual volume ≥200 mL to identify intolerance was also conducted.

Results: Data from 1,888 ICU patients were included. The incidence of intolerance was 30.5% and occurred after a median 3 days from EN initiation. Patients remained intolerant for a mean (±SD) duration of 1.9 ± 1.3 days . Intolerance was associated with worse nutrition adequacy vs the tolerant (56% vs 64%, P < .0001), fewer VFDs (2.5 vs 11.2, P < .0001), increased ICU stay (14.4 vs 11.3 days, P < .0001), and increased mortality (30.8% vs 26.2, P = .04). The sensitivity analysis demonstrated that intolerance remained associated with negative outcomes. Although mortality was greater among the intolerant patients, this was not statistically significant.

Conclusions: Intolerance occurs frequently during EN in critically ill patients and is associated with poorer nutrition and clinical outcomes.