Low versus standard calorie and protein feeding in ventilated adults with shock: a randomised, controlled, multicentre, open-label, parallel-group trial (NUTRIREA-3).

BACKGROUND: The optimal calorie and protein intakes at the acute phase of severe critical illness remain unknown. We hypothesised that early calorie and protein restriction improved outcomes in these patients, compared with standard calorie and protein targets. METHODS: The pragmatic, randomised, controlled, multicentre, open-label, parallel-group NUTRIREA-3 trial was performed in 61 French intensive care units (ICUs). Adults (≥18 years) receiving invasive mechanical ventilation and vasopressor support for shock were randomly assigned to early nutrition (started within 24 h after intubation) with either low or standard calorie and protein targets (6 kcal/kg per day and 0·2-0·4 g/kg per day protein vs 25 kcal/kg per day and 1·0-1·3 g/kg per day protein) during the first 7 ICU days. The two primary endpoints were time to readiness for ICU discharge and day 90 all-cause mortality. Key secondary outcomes included secondary infections, gastrointestinal events, and liver dysfunction. The trial is registered on ClinicalTrials.gov, NCT03573739, and is completed. FINDINGS: Of 3044 patients randomly assigned between July 5, 2018, and 8 Dec 8, 2020, eight withdrew consent to participation. By day 90, 628 (41·3%) of 1521 patients in the low group and 648 (42·8%) of 1515 patients in the standard group had died (absolute difference -1·5%, 95% CI -5·0 to 2·0; p=0·41). Median time to readiness for ICU discharge was 8·0 days (IQR 5·0-14·0) in the low group and 9·0 days (5·0-17·0) in the standard group (hazard ratio [HR] 1·12, 95% CI 1·02 to 1·22; p=0·015). Proportions of patients with secondary infections did not differ between the groups (HR 0·85, 0·71 to 1·01; p=0·06). The low group had lower proportions of patients with vomiting (HR 0·77, 0·67 to 0·89; p<0·001), diarrhoea (0·83, 0·73 to 0·94; p=0·004), bowel ischaemia (0·50, 0·26 to 0·95; p=0·030), and liver dysfunction (0·92, 0·86-0·99; p=0·032). INTERPRETATION: Compared with standard calorie and protein targets, early calorie and protein restriction did not decrease mortality but was associated with faster recovery and fewer complications. FUNDING: French Ministry of Health.

Factors associated with acute mesenteric ischemia among critically ill ventilated patients with shock: a post hoc analysis of the NUTRIREA2 trial.

PURPOSE: Acute mesenteric ischemia (AMI) is a rare, but life-threatening condition occurring among critically ill patients. Several factors have been associated with AMI, but the causal link is debated, most studies being retrospective. Among these factors, enteral nutrition (EN) could be associated with AMI, in particular among patients with shock. We aimed to study the factors independently associated with AMI in a post hoc analysis of the NUTRIREA-2 trial including 2410 critically ill ventilated patients with shock, randomly assigned to receive EN or parenteral nutrition (PN). METHODS: Post hoc analysis of the NUTRIREA-2 trial was conducted. Ventilated adults with shock were randomly assigned to receive EN or PN. AMI was assessed by computed tomography, endoscopy, or laparotomy. Factors associated with AMI were studied by univariate and multivariate analysis. RESULTS: 2410 patients from 44 French intensive care units (ICUs) were included in the study: 1202 patients in the enteral group and 1208 patients in the parenteral group. The median age was 67 [58-76] years, with 67% men, a SAPS II score of 59 [46-74], and a medical cause for ICU admission in 92.7%. AMI was diagnosed among 24 (1%) patients, mainly by computed tomography (79%) or endoscopy (38%). The mechanism of AMI was non-occlusive mesenteric ischemia (n = 12), occlusive (n = 4), and indeterminate (n = 8). The median duration between inclusion in the trial and AMI diagnosis was 4 [1-11] days. Patients with AMI were older, had a higher SAPS II score at ICU admission, had higher plasma lactate, creatinine, and ASAT concentrations and lower hemoglobin concentration, had more frequently EN, dobutamine, and CVVHDF at inclusion, developed more frequently bacteremia during ICU stay, and had higher 28-day and 90-day mortality rates compared with patients without AMI. By multivariate analysis, AMI was independently associated with EN, dobutamine use, SAPS II score ≥ 62 and hemoglobin concentration ≤ 10.9 g/dL. CONCLUSION: Among critically ill ventilated patients with shock, EN, dobutamine use, SAPS II score ≥ 62 and hemoglobin ≤ 10.9 g/dL were independently associated with AMI. Among critically ill ventilated patients requiring vasopressors, EN should be delayed or introduced cautiously in case of low cardiac output requiring dobutamine and/or in case of multiple organ failure with high SAPS II score.

Impact of early low-calorie low-protein versus standard-calorie standard-protein feeding on outcomes of ventilated adults with shock: design and conduct of a randomised, controlled, multicentre, open-label, parallel-group trial (NUTRIREA-3).

INTRODUCTION: International guidelines include early nutritional support (≤48 hour after admission), 20-25 kcal/kg/day, and 1.2-2 g/kg/day protein at the acute phase of critical illness. Recent data challenge the appropriateness of providing standard amounts of calories and protein during acute critical illness. Restricting calorie and protein intakes seemed beneficial, suggesting a role for metabolic pathways such as autophagy, a potential key mechanism in safeguarding cellular integrity, notably in the muscle, during critical illness. However, the optimal calorie and protein supply at the acute phase of severe critical illness remains unknown. NUTRIREA-3 will be the first trial to compare standard calorie and protein feeding complying with guidelines to low-calorie low-protein feeding. We hypothesised that nutritional support with calorie and protein restriction during acute critical illness decreased day 90 mortality and/or dependency on intensive care unit (ICU) management in mechanically ventilated patients receiving vasoactive amine therapy for shock, compared with standard calorie and protein targets. METHODS AND ANALYSIS: NUTRIREA-3 is a randomised, controlled, multicentre, open-label trial comparing two parallel groups of patients receiving invasive mechanical ventilation and vasoactive amine therapy for shock and given early nutritional support according to one of two strategies: early calorie-protein restriction (6 kcal/kg/day-0.2-0.4 g/kg/day) or standard calorie-protein targets (25 kcal/kg/day, 1.0-1.3 g/kg/day) at the acute phase defined as the first 7 days in the ICU. We will include 3044 patients in 61 French ICUs. Two primary end-points will be evaluated: day 90 mortality and time to ICU discharge readiness. The trial will be considered positive if significant between-group differences are found for one or both alternative primary endpoints. Secondary outcomes include hospital-acquired infections and nutritional, clinical and functional outcomes. ETHICS AND DISSEMINATION: The NUTRIREA-3 study has been approved by the appropriate ethics committee. Patients are included after informed consent. Results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03573739.

Enteral versus parenteral early nutrition in ventilated adults with shock: a randomised, controlled, multicentre, open-label, parallel-group study (NUTRIREA-2).

BACKGROUND: Whether the route of early feeding affects outcomes of patients with severe critical illnesses is controversial. We hypothesised that outcomes were better with early first-line enteral nutrition than with early first-line parenteral nutrition. METHODS: In this randomised, controlled, multicentre, open-label, parallel-group study (NUTRIREA-2 trial) done at 44 French intensive-care units (ICUs), adults (18 years or older) receiving invasive mechanical ventilation and vasopressor support for shock were randomly assigned (1:1) to either parenteral nutrition or enteral nutrition, both targeting normocaloric goals (20-25 kcal/kg per day), within 24 h after intubation. Randomisation was stratified by centre using permutation blocks of variable sizes. Given that route of nutrition cannot be masked, blinding of the physicians and nurses was not feasible. Patients receiving parenteral nutrition could be switched to enteral nutrition after at least 72 h in the event of shock resolution (no vasopressor support for 24 consecutive hours and arterial lactate <2 mmol/L). The primary endpoint was mortality on day 28 after randomisation in the intention-to-treat-population. This study is registered with ClinicalTrials.gov, number NCT01802099. FINDINGS: After the second interim analysis, the independent Data Safety and Monitoring Board deemed that completing patient enrolment was unlikely to significantly change the results of the trial and recommended stopping patient recruitment. Between March 22, 2013, and June 30, 2015, 2410 patients were enrolled and randomly assigned; 1202 to the enteral group and 1208 to the parenteral group. By day 28, 443 (37%) of 1202 patients in the enteral group and 422 (35%) of 1208 patients in the parenteral group had died (absolute difference estimate 2·0%; [95% CI -1·9 to 5·8]; p=0·33). Cumulative incidence of patients with ICU-acquired infections did not differ between the enteral group (173 [14%]) and the parenteral group (194 [16%]; hazard ratio [HR] 0·89 [95% CI 0·72-1·09]; p=0·25). Compared with the parenteral group, the enteral group had higher cumulative incidences of patients with vomiting (406 [34%] vs 246 [20%]; HR 1·89 [1·62-2·20]; p<0·0001), diarrhoea (432 [36%] vs 393 [33%]; 1·20 [1·05-1·37]; p=0·009), bowel ischaemia (19 [2%] vs five [<1%]; 3·84 [1·43-10·3]; p=0·007), and acute colonic pseudo-obstruction (11 [1%] vs three [<1%]; 3·7 [1·03-13·2; p=0·04). INTERPRETATION: In critically ill adults with shock, early isocaloric enteral nutrition did not reduce mortality or the risk of secondary infections but was associated with a greater risk of digestive complications compared with early isocaloric parenteral nutrition. FUNDING: La Roche-sur-Yon Departmental Hospital and French Ministry of Health.

Impact of early enteral versus parenteral nutrition on mortality in patients requiring mechanical ventilation and catecholamines: study protocol for a randomized controlled trial (NUTRIREA-2).

BACKGROUND: Nutritional support is crucial to the management of patients receiving invasive mechanical ventilation (IMV) and the most commonly prescribed treatment in intensive care units (ICUs). International guidelines consistently indicate that enteral nutrition (EN) should be preferred over parenteral nutrition (PN) whenever possible and started as early as possible. However, no adequately designed study has evaluated whether a specific nutritional modality is associated with decreased mortality. The primary goal of this trial is to assess the hypothesis that early first-line EN, as compared to early first-line PN, decreases day 28 all-cause mortality in patients receiving IMV and vasoactive drugs for shock. METHODS/DESIGN: The NUTRIREA-2 study is a multicenter, open-label, parallel-group, randomized controlled trial comparing early PN versus early EN in critically ill patients requiring IMV for an expected duration of at least 48 hours, combined with vasoactive drugs, for shock. Patients will be allocated at random to first-line PN for at least 72 hours or to first-line EN. In both groups, nutritional support will be started within 24 hours after IMV initiation. Calorie targets will be 20 to 25 kcal/kg/day during the first week, then 25 to 30 kcal/kg/day thereafter. Patients receiving PN may be switched to EN after at least 72 hours in the event of shock resolution (no vasoactive drugs for 24 consecutive hours and arterial lactic acid level below 2 mmol/L). On day 7, all patients receiving PN and having no contraindications to EN will be switched to EN. In both groups, supplemental PN may be added to EN after day 7 in patients with persistent intolerance to EN and inadequate calorie intake. We plan to recruit 2,854 patients at 44 participating ICUs. DISCUSSION: The NUTRIREA-2 study is the first large randomized controlled trial designed to assess the hypothesis that early EN improves survival compared to early PN in ICU patients. Enrollment started on 22 March 2013 and is expected to end in November 2015. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01802099 (registered 27 February 2013).