Background & aims: Critically ill patients requiring prolonged intensive care (ICU) treatment are at high risk of malnutrition, which latter contributes to worsening outcome. Having observed that despite the presence of a nutrition protocol and dieticians, the patients with persistent critical illness (PCI) had been underfed during their ICU stay and particularly during the first 10 days, the aim was to analyse the impact of the organisational changes that were proposed to prevent the observed malnutrition. Methods: Before (Period A) and after (Period B) study enrolling critically ill patients consecutively admitted, requiring >10 days of ICU treatment. The intervention consisted in increasing the early morning interactions between dieticians, nurses, and physicians, while modifying the computer visualisation of the dietician proposals. The primary endpoint was a reduction in the cumulative energy balance in period B. The ICU stay was divided in early ICU stay (first 10 days) and late ICU stay (day 11 to day 30). Other variables: protein, glucose, and prealbumin. Results: Altogether, 205 patients (150 and 55 in period A and B respectively) were enrolled in the PCI program. Patient characteristics were similar over both periods except for lower SAPSII score in period B. There was no difference in nutritional pattern in the first 10 days between periods. The cumulate energy balance was less negative from day 11e30 in period B than in A (À884 vs À1566 kcal; p ¼ 0.033). There was a one-day reduction in the median duration of fasting in period B (p < 0.0001). Overall compliance with nutrition protocol improved in period B with an earlier first indirect calorimetry (p ¼ 0.003) and prealbumin measurement (p < 0.001), the latter increasing significantly more during ICU stay. Conclusion: Organizational changes that allowed an early identification of patients at nutritional risk, an increased targeted dieticians intervention and a better inter-disciplinary work was associated with a reduction in undue fasting, and significantly improved energy balances.