[Guidelines for nutrition support in critically ill patient]

Feeding interruptions for extubation and other procedures

PURPOSE OF REVIEW

The objective of this review is to examine the available evidence concerning feeding interruptions before extubation and other medical procedures in ICUs. We will analyze the physiological mechanisms involved, the potential risks associated with feeding interruptions, as well as the results of recent clinical studies. Additionally, we will explore current practices and recommendations from major professional societies, as well as recent innovations aimed at minimizing feeding interruptions.

RECENT FINDINGS

Fasting before extubation is a common yet heterogeneous practice, varying across ICUs. Although dysphagia is a frequent complication after extubation, its prevalence decreases over time. However, physiologically, fasting before extubation appears ineffective in reducing gastric content or preventing aspiration. The Ambroisie study demonstrated that continuing enteral nutrition up to extubation is not inferior to a 6 h fasting strategy in terms of extubation failure at 7 days. The management of perioperative nutrition in intubated patients is debated. A retrospective study found no significant difference in postoperative respiratory events between patients fasting for at least 6 h and those fasting less or not at all but further prospective randomized studies are needed for definitive conclusions. For abdominal and digestive surgeries, fasting remains necessary to simplify procedures and reduce contamination risks. For invasive ICU procedures, such as catheter placement, the continuation of enteral nutrition appears reasonable. However, for percutaneous tracheotomy, limited evidence suggests no clear benefit from fasting, though the risk of large-volume aspiration during the procedure raises concerns. The approach to nutrition in this context requires further investigation.

SUMMARY

Fasting before extubation in ICUs is a common practice inherited from anesthesia, aiming to reduce the risk of aspiration. The Ambroisie study demonstrates that continuing enteral nutrition until extubation is not inferior to a 6 h fasting strategy regarding extubation failure at 7 days.

Postoperative nutrition in the setting of enhanced recovery programmes

Patients undergoing major surgery for gastrointestinal cancer are at high risk of developing or worsening malnutrition and sarcopenia. In malnourished patients, preoperative nutritional support may not be sufficient and so postoperative support is advised. This narrative review addresses several aspects of postoperative nutritional care in the setting of enhanced recovery programmes. Early oral feeding, therapeutic diet, oral nutritional supplements, immunonutrition, and probiotics are discussed. When postoperative intake is insufficient, nutritional support favouring the enteral route is recommended. Whether this approach should use a nasojejunal tube or jejunostomy is still a matter of debate. In the setting of enhanced recovery programmes with early discharge, nutritional follow-up and care should be continued beyond the short time in hospital. In enhanced recovery programmes, the main specific aspects of nutrition are patient education, early oral intake, and post-discharge care. The other aspects do not differ from conventional care.

Quality appraisal of clinical nutrition practice guidelines for critically ill adult patients: a systematic review using the Advancing Guideline Development, Reporting and Evaluation in Health Care instrument II (AGREE-II) and AGREE-Recommendation Excellence (AGREE-REX)

Nutritional therapy should follow evidence-based practice, thus several societies regarding nutrition and critical care have developed specific Clinical Practice Guidelines (CPG). However, to be regarded as trustworthy, the quality of the CPG for critically ill patients and its recommendations need to be high. This systematic review aimed to appraise the methodology and recommendations of nutrition CPG for critically ill patients. We performed a systematic review (protocol number CRD42020184199) with literature search conducted on PubMed, Embase, Cochrane Library and other four specific databases of guidelines up to October 2021. Two reviewers, independently, assessed titles and abstracts and potentially eligible full-text reports to determine eligibility and subsequently four reviewers appraised the guidelines quality using the Advancing Guideline Development, Reporting and Evaluation in Health Care instrument II (AGREE-II) and AGREE-Recommendation Excellence (AGREE-REX). Ten CPG for nutrition in critically ill patients were identified. Only Academy of Nutrition and Dietetics and European Society of Intensive Care Medicine had a total acceptable quality and were recommended for daily practice according AGREE-II. None of the CPG recommendations had an overall quality score above 70 %, thus being classified as moderate quality according AGREE-REX. The methodological evaluation of the critically ill adult patient CPG revealed significant discrepancies and showed a need for improvement in its development and/or reporting. In addition, recommendations about nutrition care process presented a moderate quality.

Dynamic metabolic changes measured by indirect calorimetry during the early phase of septic shock: a prospective observational pilot study

BACKGROUND AND AIMS

Energy metabolism (energy deficit, substrate consumption) in the early phase of septic shock is not clearly understood. The objective of this study was to describe its evolution using indirect calorimetry.

METHODS

Prospective observational pilot study including ventilated adult patients with septic shock admitted in a surgical intensive care unit (ICU). Metabolic data were collected using the COSMED Q-NRG + ® calorimeter: carbon dioxide production (VCO2), oxygen consumption (VO2), resting energy expenditure (REE), respiratory quotient (RQ) and the rate of substrate utilization (proteins, lipids, and carbohydrates). The main criterion was the evolution of the energy deficit (dE) from D1 to D6.

RESULTS

In total, 34 patients were included and 15 patients (age: 57.6 ± 12.8 years; Simplified Acute Physiology Score II: 52 ± 11) were eligible for final analysis. Time for initiation of nutritional support was 2.5 ± 1.5 days. The dE improved during the study period (slope = 2.9 [1.8; 4.2]; p < 0.001). The REE remained stable during the first week with no significant variation (slope = -0.16 [-1.49; 0.79]; p = 0.78). The RQ remained stable overall (slope = 0.01 [0.00; 0.03]; p = 0.10). The substrates utilization significantly changed at D3 in favor of protein consumption (slope = 6.50 [4.44; 8.85]; p < 0.001) with an overall significant decrease in the consumption of non-protein substrates.

CONCLUSION

Energy deficit improved while REE and RQ remained relatively stable during the first week of ICU stay. The significance of the variations of substrates consumption was unclear. These preliminary results should be further explored with larger studies.

Individualised versus conventional glucose control in critically-ill patients: the CONTROLING study-a randomized clinical trial

Purpose

Hyperglycaemia is an adaptive response to stress commonly observed in critical illness. Its management remains debated in the intensive care unit (ICU). Individualising hyperglycaemia management, by targeting the patient’s pre-admission usual glycaemia, could improve outcome.

Methods

In a multicentre, randomized, double-blind, parallel-group study, critically-ill adults were considered for inclusion. Patients underwent until ICU discharge either individualised glucose control by targeting the pre-admission usual glycaemia using the glycated haemoglobin A1c level at ICU admission (IC group), or conventional glucose control by maintaining glycaemia below 180 mg/dL (CC group). A non-commercial web application of a dynamic sliding-scale insulin protocol gave to nurses all instructions for glucose control in both groups. The primary outcome was death within 90 days.

Results

Owing to a low likelihood of benefit and evidence of the possibility of harm related to hypoglycaemia, the study was stopped early. 2075 patients were randomized; 1917 received the intervention, 942 in the IC group and 975 in the CC group. Although both groups showed significant differences in terms of glycaemic control, survival probability at 90-day was not significantly different (IC group: 67.2%, 95% CI [64.2%; 70.3%]; CC group: 69.6%, 95% CI [66.7%; 72.5%]). Severe hypoglycaemia (below 40 mg/dL) occurred in 3.9% of patients in the IC group and in 2.5% of patients in the CC group (p = 0.09). A post hoc analysis showed for non-diabetic patients a higher risk of 90-day mortality in the IC group compared to the CC group (HR 1.3, 95% CI [1.05; 1.59], p = 0.018).

Conclusion

Targeting an ICU patient’s pre-admission usual glycaemia using a dynamic sliding-scale insulin protocol did not demonstrate a survival benefit compared to maintaining glycaemia below 180 mg/dL.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-021-06526-8.

Impact of early nutrition route in patients receiving extracorporeal membrane oxygenation: A retrospective cohort study

BACKGROUND

Early nutrition management in patients receiving extracorporeal membrane oxygenation (ECMO) remains controversial. Despite its potentially beneficial effect, enteral nutrition (EN) could be associated with gastrointestinal (GI) complications. Total daily energy requirements remain difficult to achieve with ECMO support. Analysis of nutrition practices could improve nutrition management of this particular population.

METHODS

A monocentric retrospective study of patients requiring ECMO in a cardiac surgery intensive care unit (ICU) between 2010 and 2014 with follow-up ≥6 days. Nutrition support was monitored daily until ECMO weaning. We compared patients exposed (EN group, n = 49) and unexposed (No EN group (NEN), n = 63) with EN, as well as the energy and protein intakes within 4 days after initiation of ECMO. Vital status and nosocomial infections were followed up until ICU discharge. Primary outcome was the incidence of GI intolerance and risk-factor identification. Secondary outcomes included impact of nutrition inadequacy and clinical outcome.

RESULTS

A total 112 patients were analyzed, representing 969 nutrition days. Median ratio of energy and protein prescribed/required daily was 81% (58-113) and 56% (36-86), respectively. GI intolerance was experienced by 53% (26 of 49) of patients in the EN group and was only associated with ECMO duration (odds ratio, 1.14: 95% CI, 1.00-1.31; P = .05). Low-energy and protein days were not associated with clinical outcomes such as nosocomial infections.

CONCLUSION

EN is associated with almost 50% GI intolerance without clinical benefit for patients receiving ECMO. Adequacy in energy and protein amounts did not affect clinical outcome.

Refeeding syndrome after radical cystoprostatectomy: A case report

Described as a potentially lethal condition that occurs in undernourished patients, refeeding syndrome (RFD) is a severe electrolyte disturbance that includes low intracellular serum concentrations of phosphor, magnesium and potassium in patients undergoing inappropriate oral or parenteral renutrition. We report a case of RFD in a 50-year-old male patient that occurs 22 days after a radical cystoprostatectomy. The patient was anorexic after the surgery, the body mass index decreased to 12,36 kg/m². The concentrations of albumin, magnesium, phosphor, and calcium were low. The Patient was admitted into the intensive care unit for severe cachexia and poor general condition 24 after introduction of parenteral nutrition (1500 Kcal/day). The evolution was lethal with multiple organ failure.

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The refeeding syndrome (SRI) is a complication occurring in malnourished patients during the reintroduction of enteral or parenteral energy intake.

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The clinical presentation can lead to a multiple organ failure.

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Earlier detection of patients at high risk of developing RFD is the main prevention.

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Prevention by substituting electrolytes and vitamins before initiating adequate support refeeding is crucial.

Are Nutritional Guidelines Followed in the Pediatric Intensive Care Unit?

Background: French (2014) and American (2017) pediatric guidelines recommend starting enteral nutrition (EN) early in pediatric intensive care. The aims of this study were to compare the applicability of the guidelines in the pediatric intensive care unit (PICU) and to identify risk factors of non-application of the guidelines. Methods: This retrospective, single-center study was conducted in a medical-surgical PICU between 2014 and 2016. All patients from 1 month to 18 years old with a length of stay >48 h and an exclusive EN at least 1 day during the PICU stay were included. The outcome variable was application of the 2014 and 2017 guidelines, defined by energy intakes ≥90% of the recommended intake at least 1 day as defined by both guidelines. The risk factors of non-application were studied comparing "optimal EN" vs. "non-optimal EN" groups for both guidelines. Results: In total, 416 children were included (mortality rate, 8%). Malnutrition occurred in 36% of cases. The mean energy intake was 34 ± 30.3 kcal kg^-1 day^-1. The 2014 and 2017 guidelines were applied in 183 (44%) and 296 (71%) patients, respectively (p < 0.05). Following the 2017 guidelines, enteral energy intakes were considered as "satisfactory enteral intake" for 335 patients (81%). Hemodynamic failure was a risk factor of the non-application of both guidelines. Conclusion: In our PICU, the received energy intake approached the level of intake recommended by the American 2017 guidelines, which used the predictive Schofield equations and seem more useful and applicable than the higher recommendations of the 2014 guidelines. Multicenter studies to validate the pediatric guidelines seem necessary.

Nutrition During Critical Care: An Audit on Actual Energy and Protein Intakes

INTRODUCTION

Oral nutrition is delivered frequently in intensive care units (ICUs) but rarely studied. The primary objective of this study was to quantify nutrition intakes in patients exclusively orally fed (OF) and in those receiving medical nutrition solutions or both.

METHODS

Adults who stayed in a mixed ICU for ≥3 days were studied. Nutrition deficits were calculated as the difference between estimated energy or protein targets (determined by weight-based formulas) and actual intakes (recorded on a daily basis by nurses). Total volumes of enteral or parenteral nutrition solutions, propofol, and glucose infused over 24 hours were collected and energy and protein amounts were calculated. In OF patients, food intake at each meal (breakfast, lunch, and dinner) was estimated using the "one-quarter portion" method.

RESULTS

Among the 289 included patients aged 67 (57-75.5) years, 253 were fed and received, on average, 14.3 (7.8-19) kcal/kg/d and 0.53 (0.27-0.8) g/kg/d protein. In OF patients (n = 126), intakes were 9.7 (5.8-19) kcal/kg/d and 0.35 (0.17-0.57) g/kg/d protein. In the subset of OF patients with ICU stay ≥ 7 days (n = 37), respectively, 51% and 94% never received ≥80% of their energy and protein targets.

CONCLUSION

Nutrition intakes were lower by oral feeding compared with other exclusive or combined medical nutrition. Compared with the prescribed amounts, the deficit was larger for proteins than for energy.

Preoperative nutrition forseverely malnourished patients in digestive surgery: A retrospective study

INTRODUCTION

Malnutrition increases postoperative morbidity and mortality. The objective of this study was to evaluate preoperative refeeding in malnourished patients at risk of refeeding syndrome (RS).

METHODOLOGY

A retrospective study, conducted between June 2016 and January 2017, reported to the CNIL, compared two groups of malnourished patients: a group of refeeding patients (RP) and a group of non-refeeding patients (NRP). The inclusion criteria were weight loss of more than 10% or albuminemia less than 35g/L and RS risk factor. The primary endpoint was postoperative morbidity. The secondary endpoints were weight change and serum albumin over 6 months.

RESULTS

Seventy-three patients (30 RP and 43 NRP) were included. At the time of initial management, median weight loss was 18% [1-71], while albuminemia was 26g/L [13-40] in the RP group and 32.5g/L [32-48] in the NRP group (P=0.01). The overall postoperative morbidity rate was 88% (83% RP versus 90% NRP, P=0.47), and there was no significant difference between the 2 groups. The rate of anastomotic complications was 4% for RP versus 26% for NRP (P=0.03) after exclusion of liver surgery. Medium-term weight loss tended to be greater in RP (P=0.7). Nutritional support was continued until the third postoperative month in 13% of RPs vs. no NRPs (P=0.0002).

CONCLUSION

After preoperative renutrition, we did not observe a decrease in morbidity but rather a decrease in the rate of anastomotic complications in favor of the RP group. This study underscores the middle-term importance of nutritional management in view of preserving the benefits of preoperative renutrition.

Citrulline and muscle protein homeostasis in three different models of hypercatabolism

Supplementation of enteral nutrition (EN) by specific amino acids (AAs) has been proposed to prevent muscle protein loss in intensive care unit (ICU) patients. Citrulline (Cit), which has been shown to stimulate muscle protein synthesis in other situations, may be of interest in this setting. Our aim was to assess the effect of Cit in three catabolic models relevant to critical illness: endotoxemia (LPS), traumatic brain injury (TBI), and TBI with infectious complications (TBI-Ec), which are characterized by different alterations in protein homeostasis. Fifty-eight male Sprague-Dawley rats (200-220 g) were randomized to receive a standard diet ad libitum (CON, n = 9) or to undergo catabolic injuries on day 0 (D0, n = 49), and EN (Sondalis HP energy® 290 kcal/kg/d) from day 1 (D1) combined with Cit (2 g/kg/d) or isonitrogenous non-essential AAs (NEAAs) until day 3 (D3). Endotoxemia was induced by IP injection of LPS from E. coli (3 mg/kg), TBI by hydraulic percussion, and infectious complications (TBI-Ec) by administration of luminescent E. coli on D1. Nitrogen balance (ΔN) and 3-methylhistidine (3-MHis) were measured daily. Muscle protein synthesis (MPS, measured by the SUnSET method) and mTORC1 activation (S6K-1 and 4E-BP1 phosphorylation) were measured on D3 2 h after the arrest of enteral nutrition in soleus, extensor digitorum longus (EDL), gastrocnemius and tibialis muscles. ΔN was lower (p < 0.001) in all three models of injury compared with basal and CON from D1 to D3, and more negative in the LPS-CIT (p < 0.05) than in the LPS group. The 3-MHis/creatinine ratio was significantly increased on D1 in all groups compared with CON, and on D2 only in the LPS and TBI groups (p < 0.0001, LPS and TBI vs. CON). MPS was similar in all groups in soleus and tibialis but significantly higher in EDL in LPS-CIT [LPS-CIT: 4.5 ± 1.7 (mean ± SD) vs. CON: 2.3 ± 1.2; and vs. LPS-NEAA: 3.1 ± 2.3] and in gastrocnemius (LPS-CIT vs. CON; p = 0.05). S6K-1 phosphorylation in the EDL was also higher in LPS-CIT vs. CON (LPS-CIT: 0.94 ± 0.51 CON: 0.42 ± 0.28), but not in gastrocnemius. IL-6 plasma level was significantly higher in all the catabolic groups vs. CON (p < 0.005) with no difference between treatments (Cit or NEAAs). In conclusion, the TBI model showed only a rise in muscle proteolysis, whereas the LPS model displayed a rise in both protein synthesis and proteolysis. Secondly, our results show that the Cit effect varies according to the type of injury and to the muscle under study. The stimulation of MPS rate and the mTOR pathway in LPS-treated rats contrasts with degraded ΔN, suggesting that the Cit effect on protein metabolism in critically ill rats is limited at the whole-body level.

Comment je prends en charge la nutrition d’un patient en état de choc

La réponse métabolique à l’agression correspond à un ensemble de réactions à la base de l’adaptation de l’organisme aux nouvelles conditions. Ces modifications concernent des aspects métaboliques spécifiques comme le maintien de la masse protéique et/ou l’état des réserves énergétiques. L’une des principales difficultés de l’optimisation du support métabolique consiste à distinguer les changements métaboliques bénéfiques de ceux qui sont délétères pour l’organisme. Dans ce contexte, les objectifs thérapeutiques peuvent se limiter à une approche nutritionnelle s’attachant à limiter le déficit énergétique et les pertes protéiques et musculaires. Ils peuvent être plus ambitieux en essayant d’adapter les apports aux différents besoins d’un point de vue quantitatif comme qualitatif. La limitation du déficit énergétique semble être un objectif raisonnable à atteindre selon les données de la littérature. Enfin, essayer d’interférer avec la réponse métabolique à l’agression (immunomodulation, manipulations pharmacologiques des voies métaboliques, etc.) représente le degré d’intervention métabolique le plus élaboré et, si quelques données ont pu être encourageantes, il n’est pas possible d’affirmer que cet objectif soit complètement réaliste, voire même bénéfique. Les apports nutritionnels doivent être intégrés à la stratégie thérapeutique globale de prise en charge. La réponse optimale du support nutritionnel a pour but « de donner les moyens métaboliques » de la guérison.

Plasma free carnitine in severe trauma: Influence of the association with traumatic brain injury

BACKGROUND

Metabolic response to severe trauma requires early nutritional resuscitation. Carnitine is essential for lipolysis, the energy source during this hypercatabolic phase. However l-carnitine is not present in nutritional replacement solutions. Furthermore, free carnitine depletion, defined as carnitine plasma level under 36μmol/L, was not adequately reported in adult patients with severe trauma. The aim of this study was to assess plasma free carnitine levels and factors of variation in severe trauma.

METHOD

Our observational study concerned 38 trauma patients including 18 with traumatic brain injury (TBI). On the third day after trauma, plasma free carnitine concentration was determined (by enzymatic method) while patients received artificial nutrition.

RESULTS

Low plasmatic free carnitine concentration was evidenced in 95% of the patients with a median value of 18μmol/L (11-47). Univariate analysis showed that mean arterial pressure, serum urea, CKD-EPI and patients with TBI were significantly associated with plasma free carnitine concentration less than 18μmol/L. Lower plasma free carnitine concentration was observed in the group of patients with TBI with 17.72μmol/L (11-36) versus 21.5μmol/L (11-47) for others patients (p=0.031). Logistic regression analysis showed that severe trauma with TBI and CKD-EPI above 94mL/min/1.73m2 appeared to be independent predictor of lower free carnitine plasmatic concentration (Goodness of fit=0.87 and AUC=0.89).

CONCLUSION

Our observations support hypotheses that plasma free carnitine concentration is lowered in severe injured patients especially for TBI patients and patients with estimated GFR above 94mL/min/1.73m².

[Wasting in chronic kidney disease: Refeeding techniques and artificial nutrition practices]

Protein energy wasting (PEW) is an independent factor associated with morbi-mortality in chronic kidney disease. Wasting is particularly common in chronic diseases of organs such as kidney disease with a major impact at the stage of dialysis. It covers 20 to 70% of patients diagnosed with chronic kidney disease according to the degree of evolution of the disease and the diagnostic method used patients. Mechanisms of PEW are based mainly on anorexia and metabolic abnormalities caused by kidney disease. Nutritional treatment differs depending on the stage of the kidney disease acute or chronic treated whether or not by dialysis. Nutritional monitoring should be regular, individualized and collaborative to detect a risk of PEW or treat installed PEW. Refeeding techniques should allow all the nutritional needs. Their indications depend on the clinic, biochemical assessment and nutrient intake.

Nutrition in critically ill adults: A systematic quality assessment of clinical practice guidelines

BACKGROUND & AIMS

Nutritional support in the acutely ill is a complex topic. Clinical practice guidelines (CPGs) have been developed to assist healthcare professionals working in this field. However, the quality of these clinical guidelines has not yet been systematically assessed. The objective of our study was to identify and assess the quality of CPGs on nutrition in critically ill adult patients.

METHODS

We performed a systematic search to identify CPGs on nutrition in critically ill adult patients. Three independent appraisers assessed six domains (scope and purpose, stakeholder involvement, rigour of development, clarity of presentation, applicability and editorial independence) of the eligible CPGs using the Appraisal of Guidelines, Research, and Evaluation II (AGREE II) instrument.

RESULTS

Nine CPGs were selected. Overall agreement among appraisers was very good (ICC: 0.853; 95% CI: 0.820-0.881). The mean scores for each AGREE domain were the following: "scope and purpose" 76.2% ± 13.7%; "stakeholder involvement" 42.8% ± 16.5%; "rigour of development" 57.9% ± 18.1%; "clarity of presentation" 76.9% ± 13.7%; "applicability" 30.1% ± 22.8%; and 42.1% ± 23.9% for "editorial independence". Four CPGs were deemed "Recommended"; three "Recommended with modifications"; and two "Not recommended". We did not observe improvement over time in the overall quality of the CPGs.

CONCLUSIONS

The overall quality of CPGs on nutrition in critically ill adults is suboptimal, with only four CPGs being recommended for clinical use. Our results highlight the need to revise and improve CPG development processes in this field.

Is early starvation beneficial for the critically ill patient?

PURPOSE OF REVIEW

Anorexia is a preserved evolutionally response that may be beneficial during acute illness. Yet current clinical practice guidelines recommend early and targeted enteral nutritional support. However, the optimal timing of the initiation of enteral nutrition and the caloric and protein requirements of critically ill patients is controversial.

RECENT FINDINGS

Starvation promotes autophagy and this may play a key role in promoting host defenses and the immune response to intracellular pathogens. Because of the perceived benefits of early enteral nutrition and the lack of clinical equipoise, randomized controlled trials comparing short-term starvation to targeted normocaloric enteral nutrition have until recently not been performed. The results of the recently reported PYTHON trial (Pancreatitis, Very Early Compared with Selective Delayed Start of Enteral Feeding) dispel the notion that short-term starvation is harmful. Furthermore, six recent randomized controlled trials that compared trophic and permissive underfeeding to normocaloric goals, failed to demonstrate any outcome benefit from the more aggressive approach. In addition, recent evidence suggests that intermittent enteral nutation may be preferable to continuous tube feeding.

SUMMARY

Limiting nutrient intake during the first 48-72 h of acute illness may be beneficial; in those patients who are unable to resume an oral diet after this time period intermittent enteral nutrition targeting 20-25 cal/kg/day is recommended.

A J-shaped relationship between caloric intake and survival in critically ill patients

Background

There is much controversy around the optimal caloric intake in intensive care unit (ICU) patients, based on the diverging results of prospective studies. Therefore, we assessed the presence of an association between caloric intake and outcome in a large cohort included in the Glucontrol study.

Methods

Patients (n = 1004) were divided into four quartiles (q1–q4) according to the daily caloric intake (n = 251/quartile). ICU, hospital and 28-day mortality and the length of stay (LOS) in ICU and in the hospital were compared between each quartile, before and after adjustment in case of differences in baseline characteristics.

Results

Caloric intake averaged 0.5 ± 0.6 (q1), 3.0 ± 0.7 (q2), 13.4 ± 5.1 (q3) and 32.4 ± 8.5 (q4) kcal/kg/day (p < 0.001 between quartiles). Comparisons among quartiles revealed that ICU, hospital and 28-day mortality were lower in q2 than in the other quartiles. ICU and hospital LOS were lower in q1 and q2. After adjustment for age, type of admission and severity scores, hospital mortality was lower in q2 than in the other quartiles, and LOS was lower in q1and q2 than in q3–q4.

Conclusions

In this large and heterogeneous cohort of ICU short stayers, a J-shaped relationship between the amount of calories provided and outcome was found. These hypothesis generating findings are consistent with the concept of improved clinical outcome by early energy restriction.

Trial registration#: ClinicalTrials.gov# NCT00107601, EUDRA-CT Number: 200400391440

Modulation of Dietary Lipid Composition During Acute Respiratory Distress Syndrome: Systematic Review and Meta-Analysis

BACKGROUND

Pharmaconutrition including omega-3 and competitive analogs of omega-6 fatty acids has been used to modulate the inflammatory response during acute respiratory distress syndrome (ARDS). The clinical benefit of this approach when assessed in prospective randomized clinical trials has been inconsistent. We tried to assess the reasons for the conflicting results, including the possible influence of the composition of the control solution.

METHODS

We collected data from studies listed in PubMed, Ovid, the Cochrane Database of Systematic Reviews, Embase, the U.S. National Institute of Health database, and the ARDSnet database up to March 2013. We included all trials that evaluated effects of enteral pharmaconutrition vs a control solution on mortality, ventilator-free days, length of stay (LOS) in the intensive care unit (ICU), and ICU-free days. A sensitivity analysis was carried out to study the influence of the lipid content of the control solution.

RESULTS

We found 7 eligible studies (802 patients; 405 randomized to pharmaconutrition). The aggregated results showed no overall effect on mortality (risk ratio [RR] = 0.83 [0.55-1.25], P = .37), but there was a mortality benefit when only studies in which pharmaconutrition was compared to a lipid-rich control solution were considered (RR = 0.57 [0.41-0.78], P < .001). ICU LOS was shorter in patients randomized to pharmaconutrition (RR = 0.5 [0.85-0.16]).

CONCLUSION

Use of enteral pharmaconutrition in patients with ARDS was associated with decreased mortality only when the comparator solution contained a greater amount of lipid than is currently recommended. Hence, there is insufficient evidence to support the use of enteral pharmaconutrition in ARDS.