A randomized controlled pilot study to evaluate the effect of an enteral formulation designed to improve gastrointestinal tolerance in the critically ill patient—the SPIRIT trial

BACKGROUND Diarrhea is frequent in patients in intensive care units (ICU) and is associated with discomfort and complications and may increase the length of stay and nursing workload. METHODS This was a prospective, double-blind, randomized, controlled single-center pilot study to assess the incidence and frequency of diarrhea and the respective effects of a modified enteral diet (intervention: Peptamen® AF, rich in proteins, medium chain triglycerides and fish oil) compared to a standard diet (control: Isosource® Energy) in 90 randomized adult patients (intervention, n = 46; control, n = 44) with an ICU stay ≥5 days and tube feeding ≥3 days. Tube feeding was initiated within 72 h of ICU admission and continued up to 10 days. The caloric goal was adjusted to needs by indirect calorimetry. Gastrointestinal function, nutritional intake, and nursing workload were recorded. Follow-up was until 28 days after randomization. RESULTS Median age was 63.3 (interquartile range (IQR) 51.0-73.2) years and Simplified Acute Physiology Score (SAPS) II was 61.0 (IQR 47.8-74). Time to reach caloric goal (intervention: 2.2 (0.8-3.7) days (median, IQR); control: 2.0 (1.3-2.7) days; p = 0.16), length of time on study nutrition (intervention: 5.0 (3.6-6.4) days; control: 7.0 (5.3-8.7) days; p = 0.26), and calorie intake (intervention: 18.0 (12.5-20.9) kcal/kg/day; control 19.7 (17.3-23.1) kcal/kg/day; p = 0.08) did not differ between groups, with a higher protein intake for Peptamen® group (1.13 (0.78-1.31) g/kg/day vs 0.80 (0.70-0.94); p < 0.001). No difference in diarrhea incidence (intervention group: 29 (64%); control group: 31 (70%); p = 0.652), use of fecal collectors (23 (51%) vs. 24 (55%); p = 0.83), or diarrhea-free days (161 (64%) vs 196 (68%); p = 0.65) was found. Nursing workload and cost for diarrhea care were not different between the groups. In a post-hoc analysis, adjusted for treatment group, age, sex, and SAPS II score, diarrhea was associated with length of mechanical ventilation (9.5 (6.0-13.1) vs. 3.9 (3.2-4.6) days; p = 0.006) and length of ICU stay (11.0 (8.9-13.1) vs. 5.0 (3.8-6.2) days; p = 0.001). CONCLUSIONS In this pilot study, we found a high incidence of diarrhea, which was not attenuated by Peptamen® AF. Patients with diarrhea stayed longer in the ICU. TRIAL REGISTRATION ClinicalTrials.gov identifier, NCT01581957 . Registered on 18 April 2012.