ESPEN Guidelines on Enteral Nutrition: Intensive care

Understanding the mechanisms of glutamine action in critically ill patients

Glutamine (Gln) is an important energy source and has been used as a supplementary energy substrate. Furthermore, Gln is an essential component for numerous metabolic functions, including acid-base homeostasis, gluconeogenesis, nitrogen transport and synthesis of proteins and nucleic acids. Therefore, glutamine plays a significant role in cell homeostasis and organ metabolism. This article aims to review the mechanisms of glutamine action during severe illnesses. In critically ill patients, the increase in mortality was associated with a decreased plasma Gln concentration. During catabolic stress, Gln consumption rate exceeds the supply, and both plasma and skeletal muscle pools of free Gln are severely reduced. The dose and route of Gln administration clearly influence its effectiveness: high-dose parenteral appears to be more beneficial than low-dose enteral administration. Experimental studies reported that Gln may protect cells, tissues, and whole organisms from stress and injury through the following mechanisms: attenuation of NF (nuclear factor)-kB activation, a balance between pro- and anti-inflammatory cytokines, reduction in neutrophil accumulation, improvement in intestinal integrity and immune cell function, and enhanced of heat shock protein expression. In conclusion, high-doses of parenteral Gln (>0.50 g/kg/day) demonstrate a greater potential to benefit in critically ill patients, although Gln pathophysiological mechanisms requires elucidation.

Rationale and use of n-3 fatty acids in artificial nutrition

Lipids traditionally used in artificial nutrition are based on n-6 fatty acid-rich vegetable oils like soyabean oil. This may not be optimal because it may present an excessive supply of linoleic acid. One alternative to the use of soyabean oil is its partial replacement by fish oil, which contains n-3 fatty acids. These fatty acids influence inflammatory and immune responses and so may be useful in particular situations where those responses are not optimal. Fish oil-containing lipid emulsions have been used in parenteral nutrition in adult patients post-surgery (mainly gastrointestinal). This has been associated with alterations in patterns of inflammatory mediators and in immune function and, in some studies, a reduction in length of intensive care unit (ICU) and hospital stay. Perioperative administration of fish oil may be superior to post-operative. Parenteral fish oil has been used in critically ill adults. Here the influence on inflammatory processes, immune function and clinical endpoints is not clear, since there are too few studies and those that are available report contradictory findings. Fish oil is included in combination with other nutrients in various enteral formulas. In post-surgical patients and in those with mild sepsis or trauma, there is clinical benefit from a formula including fish oil and arginine. A formula including fish oil, borage oil and antioxidants has demonstrated marked benefits on gas exchange, ventilation requirement, new organ failures, ICU stay and mortality in patients with acute respiratory distress syndrome, acute lung injury or severe sepsis.

Interactions between ω3 polyunsaturated fatty acids and arginine on nutritional and immunological aspects in severe inflammation

BACKGROUND & AIMS

Immune-enhancing diets (IEDs) contain a mixture of nutrients claimed to have immunological properties. Therefore, it seemed relevant to determine the effect of each of their components. The aim of this study was to examine the role of arginine (Arg) and ω3 polyunsaturated fatty acids (ω3 PUFAs) in the effect of an IED (Crucial(®)) in a validated rat model of inflammation induced by turpentine (TI).

METHODS

Forty-two rats were randomized into five groups: AL (ad libitum), TI-EN (TI+standard enteral nutrition (EN): Sondalis(®)HP), TI-EN-Arg (TI+standard EN+Arg in equimolar concentration to Arg in the IED), TI-M-IED (TI+modified IED containing the same ω6/ω3 ratio as in standard EN) and TI-IED (TI+Crucial(®)). Blood was sampled to determine CD25 receptor density on lymphocytes. TNF-α, IL-6 and NO (production and expression) were evaluated on isolated macrophages. Mesenteric lymph nodes, spleen and liver were cultured for analysis of enterobacterial translocation and dissemination.

RESULTS

CD25 density was decreased after TI and was corrected in the TI-EN-Arg, TI-M-IED and TI-IED groups (p<0.05). TI induced an alteration of macrophage mRNA expression of IL-6, TNF-α and iNOS, corrected in the TI-EN-Arg and TI-M-IED groups (p<0.05), but not by the IED. Enterobacterial translocation was observed in all treated groups, nevertheless the amount tended (p=0.054) to be lower in the TI-EN-Arg group.

CONCLUSIONS

Arg and ω3 PUFAs make a major contribution to IED effects, but our study shows interaction between them on macrophage reactivity. This indicates that the individual properties of each pharmaconutrient are not additive in IEDs.

Immunonutrition and critical illness: an update

Dietary supplementation with nutrients that have physiologic effects on immune function has been shown to be beneficial in subsets of patients with surgical and medical critical illness. However, several meta-analyses have suggested potential harm when immune nutrients are used inappropriately. This has led to concern among clinicians that in turn has curtailed the more widespread use of immunonutrition as a therapeutic modality. This article discusses the mechanisms by which immune nutrients can be used to modulate alterations in innate and acquired immunity associated with critical illness. In addition, recent evidence-based clinical practice guidelines for use of immunonutrition in adults is reviewed as a means to clarify some of the more controversial issues and provide a "roadmap" for the practitioner.

Bedside adherence to clinical practice guidelines for enteral nutrition in critically ill patients receiving mechanical ventilation: a prospective, multi-centre, observational study

Introduction

The primary aim was to measure the amount of nutrients required, prescribed and actually administered in critically ill patients. Secondary aims were to assess adherence to clinical practice guidelines, and investigate factors leading to non-adherence.

Methods

Observational, multicenter, prospective study, including 203 patients in a total of 19 intensive care units in France. The prescribed calorie supply was compared with the theoretical minimal required calorie intake (25 Kcal/Kg/day) and with the supply actually delivered to the patient to calculate the ratio of calories prescribed/required and the ratio of calories delivered/prescribed. Clinical factors suspected to influence enteral nutrition were analyzed by univariate and multivariate analysis.

Results

The median ratio of prescribed/required calories per day was 43 [37-54] at day 1 and increased until day 7. From day 4 until the end of the study, the median ratio was > 80%. The median ratio of delivered/prescribed per day was > 80% for all 7 days from the start of enteral nutrition. Among the variables tested (hospital type, use of a local nutrition protocol, sedation, vasoactive drugs, number of interruptions of enteral nutrition and measurement of gastric residual volume), only measurement of residual volume was significant by univariate analysis. This was confirmed by multivariate analysis, where gastric residual volume measurement was the only variable independently associated with the ratio of delivered/prescribed calories (OR = 1.38; 95%CI, 1.12-2.10, p = .024).

Conclusions

The translation of clinical research and recommendations for enteral nutrition into routine bedside practice in critically ill patients receiving mechanical ventilation was satisfactory, but could probably be improved with a multidisciplinary approach.

Selenium and glutamine supplements: where are we heading? A critical care perspective

PURPOSE OF REVIEW

There is considerable interest in glutamine and selenium in critical care as both offer the potential to enhance host defences, through different but complimentary mechanisms and may reduce subsequent infections and mortality. The SIGNET trial (randomized controlled factorial trial) is the largest, critical care study of both supplements. The data have been presented publicly, but the data are not published or available for review and will therefore not be discussed fully in this update. In the present review I will explore the recently available (past 1-2 years) published literature.

RECENT FINDINGS

The current literature demonstrates that there are currently insufficient data to enable confident recommendations on the optimal route, timing, duration and dosage of each of these nutritional supplements. The pending results of SIGNET, the largest critical care trial of parenteral nutrition supplemented by glutamine and or selenium promises to clarify some of the current ambiguities and inform future practice.

SUMMARY

To be able to confidently establish or refute the hypothesis that either glutamine or selenium alone or in combination improves outcome in critical care requires a well designed prospective randomized controlled trial. To design such a trial we require the optimal dose and duration of the nutritional supplement (balancing efficacy and toxicity, ease of administration and cost) and then conduct an adequately powered trial. Such a trial is still lacking for these two agents. There are some supportive data for selenium but the case is less strong for parenteral glutamine and weakest for enteral glutamine.

Nutrition and clinical outcome in intensive care patients

PURPOSE OF REVIEW

In the setting of ICU, the characteristics of patients have changed during the last decade. Patients are older, frequently overweight or obese, present with more chronic diseases and undernutrition. These conditions are characterized by reduced muscle mass and vulnerable homeostasis. This review sustains the hypothesis that an early and optimal nutritional support, combining enteral and parenteral nutrition, could improve the clinical outcome of ICU patients.

RECENT FINDINGS

The combination of stress and undernutrition observed in the ICUs is associated with negative energy balance, which leads to lean body mass loss. Catabolism of lean body mass has been repeatedly associated with a worsening of the clinical outcome, increased length of hospital stay, recovery and healthcare costs. Early enteral nutrition is the recommended feeding route in ICU patients, but it is often unable to fully cover the nutritional needs. Parenteral nutrition is recommended if enteral nutrition is not feasible.

SUMMARY

It is hypothesized that supplemental parenteral nutrition, together with insufficient enteral nutrition, could optimize the nutritional therapy by preventing the onset of early energy deficiency, and thus, could allow to reduce the side-effects of undernutrition and promote better chances of recovery after the ICU stay.

Considering energy deficit in the intensive care unit

PURPOSE OF REVIEW

A discrepancy has emerged between experts' recommendations on how to feed ICU patients according to their requirements using parenteral nutrition, if enteral nutrition is not reaching the target. This review describes the differences in the recent guidelines issued by the American Society of Parenteral and Enteral Nutrition (ASPEN) and the European Society of Clinical Nutrition and Metabolism (ESPEN) regarding these aspects.

RECENT FINDINGS

ASPEN/Society of Critical Care medicine (SCCM) experts hesitate to recommend the administration of parenteral nutrition to nonmalnourished ICU patients receiving some but not an adequate amount of enteral feeding during the first 7-10 days after admission. ESPEN guidelines recommend to compensate the deficit by adding parenteral nutrition after 24-48 h. These recommendations are mainly based on observational studies showing a strong correlation between negative energy balance and morbidity-mortality.

SUMMARY

The energy deficit accumulated by underfed ICU patients during the first days of stay may play an important role in ICU and hospital outcomes for long-staying ICU patients. To reach calorie requirements by artificial nutritional support without harming the patient is still a subject of debate. Future studies, some already on their way will clarify this discussion.

Early postoperative oral intake accelerates upper gastrointestinal anastomotic healing in the rat model

BACKGROUND

In our previous study, we reported that early postoperative oral feeding accelerated upper gastrointestinal anastomotic healing in rats. To investigate its underlying mechanism, we performed in vivo and in vitro experiments.

MATERIALS AND METHODS

Rats that received proximal jejunal anastomosis were divided into four groups: the enteral nutrition (EN) group were fed via gastrostomy, the total parental nutrition (TPN alone) group were fed via a venous catheter, the TPN + saline group received an additional administration of normal saline solution via gastrostomy, and the TPN + water group received an additional administration of distilled water via gastrostomy. The anastomotic bursting pressure (ABP) and the hydroxyproline content of the anastomotic tissue were measured 5 d postoperatively. In an in vitro setting, the rat gastrointestinal fibroblasts were subjected to uniaxial stretching for 60 min, and the expression of type I and type III collagen mRNA was evaluated.

RESULTS

The ABP and hydroxyproline content in the EN group, the TPN + saline group, and the TPN + water group were significantly higher than those in the TPN alone group (ABP; 214.6 ± 42, 199.4 ± 36, and 187.3 ± 29 versus 149.5 ± 49 mmHg; P < 0.01, hydroxyproline; 63.5 ± 10, 67.8 ± 13, and 64.1 ± 14 versus 50.5 ± 12 μmol/g dry tissue; P < 0.01). The mRNA levels of type I and type III collagen were increased by stretch stimulation.

CONCLUSIONS

These results suggest that mechanical loading plays a key role in anastomotic healing. Further investigations are necessary to confirm this suggestion.

Specific nutritional problems in acute kidney injury, treated with non-dialysis and dialytic modalities

Patients who develop AKI, especially in the intensive care unit (ICU), are at risk of protein-energy malnutrition, which is a major negative prognostic factor in this clinical condition. Despite the lack of evidence from controlled trials of its effect on outcome, nutritional support by the enteral (preferentially) and/or parenteral route appears clinically indicated in most cases of ICU-acquired AKI, independently of the actual nutritional status of the patient, in order to prevent deterioration in the nutritional state with all its known complications. Extrapolating from data in other conditions, it seems intrinsically unlikely that starvation of a catabolic patient is more beneficial than appropriate nutritional support by an expert team with the skills to avoid the potential complications of the enteral and parenteral nutrition methodologies. By the same token, it is ethically impossible to conduct a trial in which the control group undergoes prolonged starvation. The primary goals of nutritional support in AKI, which represents a well-known inflammatory and pro-oxidative condition, are the same as those for other critically ill patients with normal renal function, i.e. to ensure the delivery of adequate nutrition, to prevent protein-energy wasting with its attendant metabolic complications, to promote wound healing and tissue repair, to support immune system function, to accelerate recovery and to reduce mortality. Patients with AKI on RRT should receive a basic intake of at least 1.5 g/kg/day of protein with an additional 0.2 g/kg/day to compensate for amino acid/protein loss during RRT, especially when daily treatments and/or high efficiecy modalities are used. Energy intake should consist of no more than 30 kcal non-protein calories or 1.3 × BEE (Basal Energy Expenditure) calculated by the Harris-Benedict equation, with ∼30-35% from lipid, as lipid emulsions. For nutritional support, the enteral route is preferred, although it often needs to be supplemented through the parenteral route in order to meet nutritional requirements.

Nutritional assessment and support in acute kidney injury

PURPOSE OF REVIEW

Acute kidney injury (AKI) in the ICU is associated with an increased risk of protein-energy wasting (PEW), a major negative prognostic factor. This review illustrates recently published data and guidelines concerning nutritional problems in AKI, pointing out complexities and peculiarities of the syndrome.

RECENT FINDINGS

The main goals of nutritional support in AKI on renal replacement therapy (RRT) are to ensure the provision of adequate amounts of nutrients, to prevent PEW, to promote tissue reparation, to support the immune system, and possibly to reduce mortality. The enteral route should be preferred, even though parenteral nutrition is often required to target nutritional needs. Special attention should be paid both to the impact of RRT on macronutrient and micronutrient losses, and to the risk of complications. In fact, due to both the acute loss of the kidneys' homeostatic function, and the frequent need of RRT, patients with AKI are especially prone to hypoglycemia and hyperglycemia, hypertriglyceridemia, fluid balance alterations, electrolyte and acid-base derangements.

SUMMARY

This review highlights the most recent concepts and recommendations for nutritional support in AKI, stressing the need for a close integration between adequate nutrition and RRT in this clinical condition, with the aim of carefully tailoring both therapies on patients' changing needs. Recent findings about the renoprotective role of some nutrients (glutamine, omega-3 fatty acids) are also discussed.

Inflammation, vitamin deficiencies and organ failure in critically ill patients

It is unknown whether biochemical vitamin deficiencies in critical illness are associated with severity of illness, organ dysfunction, inflammation or mortality. This nested cohort study recruited 98 patients admitted as emergencies to the intensive care unit, who had a stay of greater than 48 hours. Patient data were prospectively collected. Within the first 48 hours of admission, concentrations of C-reactive protein, vitamins A, E, B1, B12 and folate were measured on arterial blood. These measures were then repeated at least once during the later (> 48 hours) period of their stay. Seventy patients (71%) had completed vitamin studies eligible for inclusion in the analysis. Ten patients died (14.3%) during their hospital stay and mortality was associated with age, admission source and severity of illness scores. Vitamin B12 concentration was weakly associated with C-reactive protein concentrations on admission to the intensive care unit (r on days one and two = 0.4 [P = 0.002], 0.36 [P = 0.04], respectively) and with the Sequential Organ Failure Assessment score between days two and four (Spearman's r = 0.361 [P = 0.04], 0.42 [P = 0.02] and 0.48 [P = 0.02], respectively). Vitamin A concentration was weakly associated with the C-reactive protein concentrations on days one and five (Spearman's r = -0.5 [P = 0.001], -0.4 [P = 0.03], respectively). Change in deficiency status of any of the vitamins over time in the first week of intensive care admission did not appear to influence mortality. We conclude that while weak correlations were identified between vitamins A and B12 and C-reactive protein and Sequential Organ Failure Assessment scores, the importance of these associations and their relationship to hospital mortality remain to be determined.

A randomised controlled comparison of early post-pyloric versus early gastric feeding to meet nutritional targets in ventilated intensive care patients

Introduction

To compare outcomes from early post-pyloric to gastric feeding in ventilated, critically ill patients in a medical intensive care unit (ICU).

Methods

Prospective randomized study. Ventilated patients were randomly assigned to receive enteral feed via a nasogastric or a post-pyloric tube. Post-pyloric tubes were inserted by the bedside nurse and placement was confirmed radiographically.

Results

A total of 104 patients were enrolled, 54 in the gastric group and 50 in the post-pyloric group. Bedside post-pyloric tube insertion was successful in 80% of patients. Patients who failed post-pyloric insertion were fed via the nasogastric route, but were analysed on an intent-to treat basis. A per protocol analysis was also performed. Baseline characteristics were similar for all except Acute Physiology and Chronic Health Evaluation II (APACHE II) score, which was higher in the post-pyloric group. There was no difference in length of stay or ventilator days. The gastric group was quicker to initiate feed 4.3 hours (2.9 - 6.5 hours) as compared to post-pyloric group 6.6 hours (4.5 - 13.0 hours) (P = 0.0002). The time to reach target feeds from admission was also faster in gastric group: 8.7 hours (7.6 - 13.0 hours) compared to 12.3 hours (8.9 - 17.5 hours). The average daily energy and protein deficit were lower in gastric group 73 Kcal (2 - 288 Kcal) and 3.5 g (0 - 15 g) compared to 167 Kcal (70 - 411 Kcal) and 6.5 g (2.8 - 17.3 g) respectively but was only statistically significant for the average energy deficit (P = 0.035). This difference disappeared in the per protocol analysis. Complication rates were similar.

Conclusions

Early post-pyloric feeding offers no advantage over early gastric feeding in terms of overall nutrition received and complications

Trial Registration

Clinical Trial: anzctr.org.au:ACTRN12606000367549

The impact of enteral feeding protocols on nutritional support in critically ill children

BACKGROUND

Studies have shown that feeding protocols may assist in achieving optimal nutritional care in critically ill children. The present study aimed to assess the impact of enteral feeding protocols on nutritional support practices through a continuous auditing process over a defined period.

MATERIALS AND METHODS

A prospective audit on nutritional practice was initiated in 1994-1995 on all ventilated patients who were admitted for more than a complete 24-h period in the paediatric intensive care unit. The audit was repeated 1997-1998, 2001 and 2005. The collection of data on outcomes included the time taken to initiate nutritional support, the proportion of patients fed via the enteral versus parenteral route, and the proportion of children reaching 50% and 70% of the estimated average requirement (EAR) by day 3. Feeding algorithms and protocols were introduced after each audit with a view to improving practices.

RESULTS

Over the study period, time taken to initiate nutrition support was reduced from 15 h (1994-1995), 8 h (1997-1998), 5.5 h (2001) to 4.5 h (2005). The proportion of patients on parenteral feeds was reduced from 11% (1994-1995) to 4% (2005). An increase was also documented in the percentage of patients receiving a daily energy provision of 50% and 70% of the EAR by day 3 after the initiation of nutritional support (6% in 1994-1995 to 21% in 2005 for 70% of EAR).

CONCLUSION

The present study demonstrates that feeding protocols improve nutritional practices in a paediatric intensive care unit. However, protocol introduction needs to be monitored regularly through audit.

Impact of not measuring residual gastric volume in mechanically ventilated patients receiving early enteral feeding: a prospective before-after study

BACKGROUND

Monitoring of residual gastric volume (RGV) to prevent aspiration is standard practice in mechanically ventilated patients receiving early enteral nutrition (EN). No data are available to support a correlation between RGV and adverse event rates. We evaluated whether not measuring RGV affected EN delivery, vomiting, or risk of nosocomial pneumonia.

METHODS

Two hundred and five eligible patients with nasogastric feeding within 48 hours after intubation were included in a 7-day prospective before-after study. Continuous 24-hour nutrition was started at 25 mL/h then increased by 25 mL/h every 6 hours, to 85 mL/h. In both groups, intolerance was treated with erythromycin (250 mg IV/6 h) and a delivery rate decrease to the previously well-tolerated rate. RGV monitoring was used during the first study period (n = 102), but not during the subsequent intervention period (n = 103). Intolerance was defined as RGV >250 mL/6 h or vomiting in the standard-practice group and as vomiting in the intervention group.

RESULTS

Groups were similar for baseline characteristics. Median daily volume of enteral feeding was higher in the intervention group (1489; interquartile range [IQR], 1349-1647) than in the controls (1381; IQR, 1151-1591; P = .002). Intolerance occurred in 47 (46.1%) controls and 27 (26.2%) intervention patients (P = .004). The vomiting rate did not differ between controls and intervention group patients (24.5% vs 26.2%, respectively; P = .34), and neither was a difference found for ventilator-associated pneumonia (19.6% vs 18.4%; P = .86).

CONCLUSION

Early EN without RGV monitoring in mechanically ventilated patients improves the delivery of enteral feeding and may not increase vomiting or ventilator-associated pneumonia.

Pediatric parenteral nutrition: putting the microscope on macronutrients and micronutrients

Parenteral nutrition can be a life-saving therapy, but its benefits need to be balanced with a unique set of risks and complications. Methods of practice vary because there is a dearth of research in the area of pediatric parenteral nutrition. This article reviews the available literature on parenteral nutrition in children and provides suggestions on prevention and management of parenteral nutrition-associated liver disease. Some of the issues discussed in this article include glucose infusion rates, cycling of parenteral nutrition, copper and manganese toxicity, and the provision of glutamine, selenium, and carnitine.

Toward protein-energy goal-oriented therapy?

Protein calorie malnutrition is a concern in critically ill patients. Prospective studies to define the ideal calorie/protein intake to administer not only to meet requirements but also to change outcome are lacking. Strack van Schijndel and colleagues have observed an improvement in survival when patients reach the calorie target according to indirect calorimetry and a protein intake of greater than 1.2 g/kg per day. Their prospective observational study sheds new light on this field.

Clinical application of subjective global assessment in Chinese patients with gastrointestinal cancer

AIM

To investigate the role of subjective global assessment (SGA) in nutritional assessment and outcome prediction of Chinese patients with gastrointestinal cancer.

METHODS

A total of 751 patients diagnosed with gastrointestinal cancer between August 2004 and August 2006 were enrolled in this study. Within 72 h after admission, SGA, anthropometric parameters, and laboratory tests were used to assess the nutritional status of each patient. The outcome variables including hospital stay, complications, and in-hospital medical expenditure were also obtained.

RESULTS

Based on the results of SGA, 389 (51.8%), 332 (44.2%), and 30 (4.0%) patients were classified into well nourished group (SGA-A), mildly to moderately malnourished group (SGA-B), and severely malnourished group (SGA-C), respectively. The prevalence of malnutrition classified by SGA, triceps skinfold thickness (TSF), mid-upper arm muscle circumference (MAMC), albumin (ALB), prealbumin (PA), and body mass index (BMI) was 48.2%, 39.4%, 37.7%, 31.3%, 21.7%, and 9.6%, respectively. In addition, ANOVA tests revealed significant differences in body mass index (BMI), TSF, PA, and ALB of patients in different SGA groups. The more severely malnourished the patient was, the lower the levels of BMI, TSF, PA, and ALB were (P < 0.05). Chi2 tests showed a significant difference in SGA classification between patients receiving different types of treatment (surgery vs chemotherapy/radiotherapy). As the nutritional status classified by SGA deteriorated, the patients stayed longer in hospital and their medical expenditures increased significantly. Furthermore, multiple regression analysis showed that SGA and serum ALB could help predict the medical expenditures and hospital stay of patients undergoing surgery. The occurrence of complications increased in parallel with the increasing grade of SGA, and was the highest in the SGA-C group (23.3%) and the lowest in the SGA-A group (16.8%).

CONCLUSION

SGA is a reliable assessment tool and helps to predict the hospital stay and medical expenditures of Chinese surgical gastrointestinal cancer patients.

Early enteral nutrition, provided within 24 h of injury or intensive care unit admission, significantly reduces mortality in critically ill patients: a meta-analysis of randomised controlled trials

PURPOSE

To determine whether the provision of early standard enteral nutrition (EN) confers treatment benefits to critically ill patients.

METHODS

Medline and EMBASE were searched. Hand citation review of retrieved guidelines and systematic reviews were undertaken, and academic and industry experts were contacted. Methodologically sound randomised controlled trials (RCTs) conducted in critically ill patient populations that compared the delivery of standard EN, provided within 24 h of intensive care unit (ICU) admission or injury, to standard care were included. The primary analysis was conducted on clinically meaningful patient-oriented outcomes. Secondary analyses considered vomiting/regurgitation, pneumonia, bacteraemia, sepsis and multiple organ dysfunction syndrome. Meta-analyses were conducted using the odds ratio (OR) metric and a fixed effects model. The impact of heterogeneity was assessed using the I (2) metric.

RESULTS

Six RCTs with 234 participants were analysed. The provision of early EN was associated with a significant reduction in mortality [OR = 0.34, 95% confidence interval (CI) 0.14-0.85] and pneumonia (OR = 0.31, 95% CI 0.12-0.78). There were no other significant differences in outcomes. A sensitivity analysis and a simulation exercise confirmed the presence of a mortality reduction.

CONCLUSION

Although the detection of a statistically significant reduction in mortality is promising, overall trial quality was low, trial size was small, and the findings may be restricted to the patient groups enrolled into included trials. The results of this meta-analysis should be confirmed by the conduct of a large multi-centre trial enrolling diverse critically ill patient groups.

Parenteral nutrition in the critically ill patient

A 67-year-old woman with type 2 diabetes mellitus undergoes extensive resection of the small bowel and right colon with a jejunostomy and colostomy because of mesenteric ischemia. In the surgical intensive care unit, severe systemic inflammatory response syndrome with possible sepsis develops. The patient is treated with volume resuscitation, vasopressor support, mechanical ventilation, broad-spectrum antibiotics, and intravenous insulin infusion. Low-dose tube feedings are initiated postoperatively through a nasogastric tube. However, these feedings are discontinued after the development of escalating vasopressor requirements, worsening abdominal distention, and increased gastric residual volume, along with an episode of emesis. The hospital nutritional-support service is consulted for feeding recommendations. A discussion with the patient's family reveals that during the previous 6 months, she lost approximately 15% of her usual body weight and decreased her food intake because of abdominal pain associated with eating. Her preoperative body weight was 51 kg (112 lb), or 90% of her ideal body weight. The physical examination reveals mild wasting of skeletal muscle and fat. Blood tests show hypomagnesemia, hypophosphatemia, and normal hepatic and renal function. Central venous parenteral nutrition is recommended.

Grasping the nutritional situation: a grounded theory study of patients' experiences in intensive care

AIM AND OBJECTIVES

The aim of this study was to provide a theoretical understanding of nutritional experiences for patients with enteral nutrition (EN) during their stay in the intensive care unit (ICU).

BACKGROUND

It is well known that EN can result in underfeeding for patients in ICUs. How the patients experience their nutritional care during their stay in the ICU remains somewhat unclear.

DESIGN AND METHODS

In this study, a grounded theory approach was chosen to conduct and analyse 14 interviews with patients and 21 observations of nutritional care during the patients' stay in an ICU.

FINDINGS

The core category 'grasping nutrition during the recovery process' was reflected in, and related to, the categories 'facing nutritional changes', 'making sense of the nutritional situation' and 'being involved with nutritional care'. While grasping the nutrition, the patients were emotionally shifting between worry, fear and failure, and relief and hope. Turning points were having the appetite back, getting rid of the feeding tube and regaining a functioning gut.

CONCLUSIONS

The patients' views of nutritional care during their stay in the ICU may contribute to understanding of how patients make sense of their nutritional changes and how they are involved in their nutritional care. This study shows that grasping the nutrition can be a way to regain some control in a situation where the patients are highly dependent on professional care. Further research is needed to develop this substantive theory in other intensive care settings to support patients' nutritional journey in intensive care.

RELEVANCE TO CLINICAL PRACTICE

Nurses can promote patients' abilities to grasp their nutritional situation during their recovery process. There is a need to focus not only on the patients' physical needs but also on their emotional and social needs.

Late-onset ventilator-associated pneumonia in nontrauma intensive care unit patients

BACKGROUND

Most studies designed to determine the factors associated with the acquisition of late-onset ventilator-associated pneumonia (VAP) were performed in critically ill trauma patients. The impact of enteral nutrition (EN) on the risk of acquiring VAP has been discussed. In this study, we assessed factors associated with late-onset VAP in nontrauma patients and determined whether nutrition provided early was associated with development of late-onset VAP in this population.

METHODS

We performed a prospective observational cohort study in a 21-bed polyvalent intensive care unit in a university hospital.

RESULTS

Three hundred sixty-one intubated adult patients with a duration of mechanical ventilation (MV) of 6 days or more were admitted over a 28-mo period. Late-onset VAP was confirmed in 76 patients (21%) by the presence of at least one microorganism at a concentration >or=10(4) colony-forming units/mL on the bronchoalveolar lavage. Gram-negative bacilli represented 75% and Staphylococcus aureus 21% of recovered organisms. Factors independently associated with late-onset VAP by multivariate analysis included a high simplified acute physiology score II score (odds ratio: 1.021; 95% confidence interval [CI]: 1.005-1.038; P = 0.01), development of acute respiratory distress syndrome during the first 5 days of MV (odds ratio: 1.98; 95% CI: 1.05-3.67; P = 0.04), and size of the endotracheal tube >or=7.5 (odds ratio: 2.06; 95% CI: 1.88-3.90; P = 0.03). EN started within 48 h of MV onset was not associated with a higher risk for late-onset VAP.

CONCLUSION

In our nontrauma patient population, early EN was not associated with development of late-onset VAP. In this population, severity of the disease during the first 5 days of MV seemed to be associated with late-onset VAP. In addition, our results suggest that the risk of late-onset VAP is higher in patients with a tube size >or=7.5 than in patients with a tube size <7.5.

Before-after study of a standardized ICU protocol for early enteral feeding in patients turned in the prone position

BACKGROUNDS & AIMS

To evaluate an intervention for improving the delivery of early enteral nutrition (EN) in patients receiving mechanical ventilation with prone positioning (PP).

METHODS

Eligible patients receiving EN and mechanical ventilation in PP were included within 48h after intubation in a before-after study. Patients were semi-recumbent when supine. Intolerance to EN was defined as residual gastric volume greater than 250ml/6h or vomiting. In the before group (n=34), the EN rate was increased by 500ml every 24h up to 2000ml/24h; patients were flat when prone and received erythromycin (250mgIV/6h) to treat intolerance. In the intervention group (n=38), the EN rate was increased by 25ml/h every 6h to 85ml/h, 25 degrees head elevation was used in PP, and prophylactic erythromycin was started at the first turn.

RESULTS

Compared to the before group, larger feeding volumes were delivered in the intervention group (median volume per day with PP, 774ml [IQR 513-925] vs. 1170ml [IQR 736-1417]; P<0.001) without increases in residual gastric volume, vomiting, or ventilator-associated pneumonia.

CONCLUSION

An intervention including PP with 25 degrees elevation, an increased acceleration to target rate of EN, and erythromycin improved EN delivery.

[Burn trauma--Part 2. Anesthesiological, surgical and intensive care management]

After initial stabilization of burn victims at the scene and in the trauma room, a tight cooperation and communication between anesthesiologists, plastic surgeons and intensive care specialists is needed for further therapy. Interdisciplinary communication about preoperative planning, timing of necrectomy and intensive care therapy is vital regarding functional and aesthetic outcome and survival rate. During burn surgery attention has to be paid to excessive blood loss and the danger of hypothermia. The main problems of intensive care therapy involve the evaluation of volume status, high demands for analgesia and sedation, high incidence of septic multiorgan failure and therapy and prophylaxis of the effects of hypermetabolism.

Parenteral and enteral nutrition in the management of neurosurgical patients in the intensive care unit

The iatrogenic malnutrition of neurosurgical patients in intensive care units (ICU) is an underestimated problem. It may cause a decrease in plasma albumin and oncotic pressure, leading to an increase in the amount of water entering the brain and increased intracranial pressure (ICP). This study was conducted to test the hypothesis that combined high-protein parenteral and enteral nutrition is beneficial for neurosurgical patients in ICU. A total of 202 neurosurgical patients in ICU (mean age+/-standard deviation, 56 years+/-16 years; male:female=1.2:1) were studied. Two consecutive 1-year time periods were compared, during which two different nutritional regimens were followed. In the first time period (Y1) patients were given a low-protein/high-fat formulation parenterally, followed by a standard enteral regimen. In the second time period (Y2) a protein-rich, combined parenteral and enteral diet was prospectively administered. The Glasgow Outcome Score was measured at 3-6 months after discharge. The following clinical parameters were recorded during the first 2 weeks after admission: ICP; albumin; cholinesterase (CHE); daily hours of ICP > 20 mmHg and cerebral perfusion pressure<70 mmHg; and Acute Physiology and Chronic Health Evaluation II (APACHE II) score. It was found that overall albumin (32.4 g/L+/-4.1g/L vs. 27.5 g/L+/-3.6g/L) and CHE was higher during Y2, although the total energy supply, glucose and fat intake was lower. Higher GOS scores were seen when patients had lower APACHE II scores and received the Y2 nutritional regimen. During Y2, the total hours of ICP > 20 mmHg were fewer. With the Y2 nutrition, maintenance of adequate cerebral perfusion required less catecholamine medication and colloidal fluid replacement. Therefore, adequate nutrition is an important parameter in the management of neurosurgical patients in ICU.

Comparison of a new unguided self-advancing jejunal tube with the endoscopic guided technique: a prospective, randomized study

OBJECTIVE

To compare the success rate of correct jejunal placement of a new self-advancing jejunal tube with the gold standard, the endoscopic guided technique, in a comparative intensive care unit (ICU) patient population.

DESIGN

Prospective, randomized study.

SETTING

Two medical ICUs at a university hospital.

PATIENTS

Forty-two mechanically ventilated patients with persisting intolerance of intragastric enteral nutrition despite prokinetic therapy.

METHODS

Patients were randomly assigned to receive an unguided self-advancing jejunal feeding tube (Tiger Tube) or an endoscopic guided jejunal tube (Freka Trelumina). Primary outcome measure was the success rate of correct jejunal placement after 24 h.

RESULTS

Correct jejunal tube placement was reached in all 21 patients using the endoscopic guided technique whereas the unguided self-advancing jejunal tube could be placed successfully in 14 out of 21 patients (100% versus 67%; P = 0.0086). In the remaining seven patients, successful endoscopic jejunal tube placement was performed subsequently. Duration of tube placement was longer in the unguided self-advancing tube group (20 +/- 12 min versus 597 +/- 260 min; P < 0.0001). Secondary outcome parameters (complication rate, number of attempts, days in correct position with accurate functional capability, days with high gastric residual volume, length of ICU stay, ICU mortality) were not statistically different between the two groups. No potentially relevant parameter predicting the failure of correct jejunal placement of the self-advancing tube could be identified.

CONCLUSIONS

Success rate of correct jejunal placement of the new unguided self-advancing tube was significantly lower than the success rate of the endoscopic guided technique.

ESPEN Guidelines on Parenteral Nutrition: intensive care

Nutritional support in the intensive care setting represents a challenge but it is fortunate that its delivery and monitoring can be followed closely. Enteral feeding guidelines have shown the evidence in favor of early delivery and the efficacy of use of the gastrointestinal tract. Parenteral nutrition (PN) represents an alternative or additional approach when other routes are not succeeding (not necessarily having failed completely) or when it is not possible or would be unsafe to use other routes. The main goal of PN is to deliver a nutrient mixture closely related to requirements safely and to avoid complications. This nutritional approach has been a subject of debate over the past decades. PN carries the considerable risk of overfeeding which can be as deleterious as underfeeding. Therefore the authors will present not only the evidence available regarding the indications for PN, its implementation, the energy required, its possible complementary use with enteral nutrition, but also the relative importance of the macro- and micronutrients in the formula proposed for the critically ill patient. Data on long-term survival (expressed as 6 month survival) will also be considered a relevant outcome measure. Since there is a wide range of interpretations regarding the content of PN and great diversity in its practice, our guidance will necessarily reflect these different views. The papers available are very heterogeneous in quality and methodology (amount of calories, nutrients, proportion of nutrients, patients, etc.) and the different meta-analyses have not always taken this into account. Use of exclusive PN or complementary PN can lead to confusion, calorie targets are rarely achieved, and different nutrients continue to be used in different proportions. The present guidelines are the result of the analysis of the available literature, and acknowledging these limitations, our recommendations are intentionally largely expressed as expert opinions.

Oxidative stress due to anesthesia and surgical trauma: importance of early enteral nutrition

Anesthesia and surgical trauma are considered major oxidative and nitrosative stress effectors resulting in the development of SIRS. In this study we evaluated the usefulness of early enteral nutrition after surgical trauma. Sixty male Wistar rats were subjected to midline laparotomy and feeding-gastrostomy. Twenty of these rats served as controls after recovering from the operation stress. The remaining rats received, through gastrostomy, enteral nutrition or placebo-feeding for 24 h. Oxidative stress markers and CC chemokine production were evaluated in rat serum and liver tissue. The operation itself was found to increase nitric oxide (NO) and malondialdehyde (MDA) and to decrease superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), as well as liver tissue energy charge (EC) in relation to controls. The rats receiving enteral feeding exhibited statistically significantly lower levels of NO and MDA, and higher levels of SOD, GSH-Px, and liver EC, in relation to placebo feeding rats. The operation significantly increased the chemokines monocyte chemoattractant protein (MCP)-1 and regulated upon activation, normal T-cell expressed, and secreted (RANTES) in rat serum, while enteral nutrition caused a further significant increase in chemokine levels in serum. mRNA chemokine expression in liver was increased in a similar pattern. These findings indicate that early enteral feeding might play an important role after surgery ameliorating oxidative stress, affecting positively the hepatic EC and regulating, via chemokine production, cell trafficking, and healing process.