An overview of evidence from systematic reviews evaluating early enteral nutrition in critically ill patients: more convincing evidence is needed

Estimating the time point for nutritional failure in patients suffering from acute brain attacks in the intensive care unit

BACKGROUND

Severe brain attack patients demonstrate hypermetabolic state and gastrointestinal dysfunction, leading to faster onset of nutritional failure.

AIM

To estimate the time point where the development of nutritional failure is more probable among patients with acute brain attacks in the intensive care unit (ICU).

METHODS

Direct bedside observation for selected nutritional parameters was performed. When enteral nutrition was initiated, observation was performed at five points over 9 days.

FINDINGS

84 patients with 55% mortality risk and on mechanical ventilation were included. Over the observation period, gastric residual volume increased (144 ml vs 196 ml), body weight decreased (79.4 kg vs 74.3 kg), and serum albumin reduced (3.6 g/dl to 3.1 g/dl). Caloric attainment and malnutrition score deteriorated, and feeding-related complications increased. Nutritional failure was evidently prevalent between the third and fifth day of observation.

CONCLUSION

An earlier period of enteral nutrition entails higher probability of nutritional failure among severe brain attack patients in the ICU.

Nutritional screening based on objective indices at admission predicts in-hospital mortality in patients with COVID-19

BACKGROUND

Could nutritional status serve as prognostic factors for coronavirus disease 2019 (COVID-19)? The present study evaluated the clinical and nutritional characteristics of COVID-19 patients and explored the relationship between risk for malnutrition at admission and in-hospital mortality.

METHODS

A retrospective, observational study was conducted in two hospitals in Hubei, China. Confirmed cases of COVID-19 were typed as mild/moderate, severe, or critically ill. Clinical data and in-hospital death were collected. The risk for malnutrition was assessed using the geriatric nutritional risk index (GNRI), the prognostic nutritional index (PNI), and the Controlling Nutritional Status (CONUT) via objective parameters at admission.

RESULTS

Two hundred ninety-five patients were enrolled, including 66 severe patients and 41 critically ill patients. Twenty-five deaths were observed, making 8.47% in the whole population and 37.88% in the critically ill subgroup. Patients had significant differences in nutrition-related parameters and inflammatory biomarkers among three types of disease severity. Patients with lower GNRI and PNI, as well as higher CONUT scores, had a higher risk of in-hospital mortality. The receiver operating characteristic curves demonstrated the good prognostic implication of GNRI and CONUT score. The multivariate logistic regression showed that baseline nutritional status, assessed by GNRI, PNI, or CONUT score, was a prognostic indicator for in-hospital mortality.

CONCLUSIONS

Despite variant screening tools, poor nutritional status was associated with in-hospital death in patients infected with COVID-19. This study highlighted the importance of nutritional screening at admission and the new insight of nutritional monitoring or therapy.

Evaluation of Nutrition Risk and Its Association With Mortality Risk in Severely and Critically Ill COVID-19 Patients

BACKGROUND

The nutrition status of coronavirus disease 2019 patients is unknown. This study evaluates clinical and nutrition characteristics of severely and critically ill patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and investigates the relationship between nutrition risk and clinical outcomes.

METHODS

A retrospective, observational study was conducted at West Campus of Union Hospital in Wuhan. Patients confirmed with SARS-CoV-2 infection by a nucleic acid-positive test and identified as severely or critically ill were enrolled in this study. Clinical data and outcomes information were collected and nutrition risk was assessed using Nutritional Risk Screening 2002 (NRS).

RESULTS

In total, 413 patients were enrolled in this study, including 346 severely and 67 critically ill patients. Most patients, especially critically ill patients, had significant changes in nutrition-related parameters and inflammatory markers. As for nutrition risk, the critically ill patients had significantly higher proportion of high NRS scores (P < .001), which were correlated with inflammatory and nutrition-related markers. Among 342 patients with NRS score ≥3, only 84 (of 342, 25%) received nutrition support. Critically ill patients and those with higher NRS score had a higher risk of mortality and longer stay in hospital. In logistic regression models, 1-unit increase in NRS score was associated with the risk of mortality increasing by 1.23 times (adjusted odds ratio, 2.23; 95% CI, 1.10-4.51; P = .026).

CONCLUSIONS

Most severely and critically ill patients infected with SARS-CoV-2 are at nutrition risk. The patients with higher nutrition risk have worse outcome and require nutrition therapy.

Database combinations to retrieve systematic reviews in overviews of reviews: a methodological study

Background

When conducting an Overviews of Reviews on health-related topics, it is unclear which combination of bibliographic databases authors should use for searching for SRs. Our goal was to determine which databases included the most systematic reviews and identify an optimal database combination for searching systematic reviews.

Methods

A set of 86 Overviews of Reviews with 1219 included systematic reviews was extracted from a previous study. Inclusion of the systematic reviews was assessed in MEDLINE, CINAHL, Embase, Epistemonikos, PsycINFO, and TRIP. The mean inclusion rate (% of included systematic reviews) and corresponding 95% confidence interval were calculated for each database individually, as well as for combinations of MEDLINE with each other database and reference checking.

Results

Inclusion of systematic reviews was higher in MEDLINE than in any other single database (mean inclusion rate 89.7%; 95% confidence interval [89.0–90.3%]). Combined with reference checking, this value increased to 93.7% [93.2–94.2%]. The best combination of two databases plus reference checking consisted of MEDLINE and Epistemonikos (99.2% [99.0–99.3%]). Stratification by Health Technology Assessment reports (97.7% [96.5–98.9%]) vs. Cochrane Overviews (100.0%) vs. non-Cochrane Overviews (99.3% [99.1–99.4%]) showed that inclusion was only slightly lower for Health Technology Assessment reports. However, MEDLINE, Epistemonikos, and reference checking remained the best combination. Among the 10/1219 systematic reviews not identified by this combination, five were published as websites rather than journals, two were included in CINAHL and Embase, and one was included in the database ERIC.

Conclusions

MEDLINE and Epistemonikos, complemented by reference checking of included studies, is the best database combination to identify systematic reviews on health-related topics.

Prognostic Performance of NUTRIC Score in Quantifying Malnutrition Risk in the Critically Ill in Congruence With the Bioelectrical Impedance Analysis

BACKGROUND

There is still no concrete guidance for assessing malnutrition risk in the critically ill. Nutrition Risk in the Critically Ill (NUTRIC) score is undertaken cautiously compared with other validated tools such as bioelectrical impedance analysis (BIA). This study aimed to assess the malnutrition risk in the critically ill using NUTRIC score and assess its congruency with the BIA.

METHODS

In this cross-section observational study, intensive care unit (ICU) patients from various etiologies were assessed using the earlier tools in addition to other prognostic markers (Acute Physiologic Assessment and Chronic Health Evaluation II [APACHE II] and Sequential Organ Failure Assessment [SOFA] scores), caloric attainment, and feeding complications.

RESULTS

Of a total 411 assessed patients, 313 (76.2%) were enterally fed, and 318 (77.4%) were mechanically ventilated. Mean age was 60.7 years, and the median of the assessment since admission was the 12th day. Of those enterally fed patients, 57.9% attained the caloric requirements. Both APACHE II and SOFA scores were compatible in ascertaining ICU mortality at a moderate level (17.88 and 7.17, respectively). The NUTRIC score and phase angle (PA) measured by BIA revealed no differences in the malnutrition risk between patients with and without enteral nutrition. However, regression indicated that the NUTRIC score has explained only 1.1% of the variance of PA after controlling other covariates (β = -0.222, P = .009, confidence interval = -0.31 to -0.05).

CONCLUSIONS

NUTRIC score has a limited prediction to the urgency of aggressive nutrition therapy within the early period of ICU admission.

Gastrointestinal Tract Dysfunction With Critical Illness: Clinical Assessment and Management

The gut is the site of digestion and absorption as well as serving as an endocrine and immune organ. All of these functions may be affected by critical illness. This review will discuss secondary effects of critical illness on the gut in terms of gastrointestinal function that is clinically observable and discuss consequences of gut dysfunction with critical illness to patient outcome. Because there is little evidence-based medicine in the veterinary field, much of our understanding of gut dysfunction with critical illness comes from animal models or from the human medical field. We can extrapolate some of these conclusions and recommendations to companion animals, particularly in dogs, who have similar gastrointestinal physiology to people. Additionally, the evidence regarding gut dysfunction in veterinary patients will be explored. By recognizing signs of dysfunction early and taking preventative measures, we may be able to increase success with treatment of critical illnesses.

The science and art of pediatric critical care nutrition

PURPOSE OF REVIEW

Nutritional status and nutrient delivery during critical illness impact clinical outcomes. We have reviewed recent studies that may guide best practices regarding nutrition therapy in critically ill children.

RECENT FINDINGS

Malnutrition is prevalent in the pediatric ICU population, and is associated with worse outcomes. Nutrition support teams, dedicated dietitians, and educational programs facilitate surveillance for existing malnutrition and nutrition risk, but specific tools for the pediatric ICU population are lacking. Estimation of macronutrient requirements is often inaccurate; novel strategies to accurately determine energy expenditure are being explored. Indirect calorimetry remains the reference method for measuring energy expenditure. Enteral nutrition is the preferred route for nutrition in patients with a functioning gut. Early enteral nutrition and delivery of adequate macronutrients, particularly protein, have been associated with improved clinical outcomes. Delivery of enteral nutrition is often interrupted because of fasting around procedures and perceived intolerance. Objective measures for detection and management of intolerance to nutrient intake are required. In low-risk patients who are able to tolerate enteral nutrition, supplemental parenteral nutrition may be delayed during the first week of critical illness.

SUMMARY

Systematic research and consensus-based practices are expected to promote optimal nutritional practices in critically ill children with the potential to improve clinical outcomes.

The role of nutritional support in the physical and functional recovery of critically ill patients: a narrative review

The lack of benefit from randomised controlled trials has resulted in significant controversy regarding the role of nutrition during critical illness in terms of long-term recovery and outcome. Although methodological caveats with a failure to adequately appreciate biological mechanisms may explain these disappointing results, it must be acknowledged that nutritional support during early critical illness, when considered alone, may have limited long-term functional impact.This narrative review focuses specifically on recent clinical trials and evaluates the impact of nutrition during critical illness on long-term physical and functional recovery.Specific focus on the trial design and methodological limitations has been considered in detail. Limitations include delivery of caloric and protein targets, patient heterogeneity, short duration of intervention, inappropriate clinical outcomes and a disregard for baseline nutritional status and nutritional intake in the post-ICU period.With survivorship at the forefront of critical care research, it is imperative that nutrition studies carefully consider biological mechanisms and trial design because these factors can strongly influence outcomes, in particular long-term physical and functional outcome. Failure to do so may lead to inconclusive clinical trials and consequent rejection of the potentially beneficial effects of nutrition interventions during critical illness.

Effect of Calories Delivered on Clinical Outcomes in Critically Ill Patients: Systemic Review and Meta-analysis

Introduction:

International guidelines are promoting early enteral nutrition (EN) as a means of feeding critically ill adult patients to improve clinical outcomes. The question of how much calorie intake is enough to improve the outcomes still remained inconclusive. Therefore, we carried out a meta-analysis to evaluate the effect of low calorie (LC) versus high calorie (HC) delivery on critically ill patients' outcomes.

Methods:

We included randomized clinical trials (RCTs) that compared LC EN with or without supplemental parenteral nutrition with HC delivery in this meta-analysis irrespective of the site of nutritional delivery in the gastrointestinal tract. We searched PubMed, EMBASE, and Cochrane central register of controlled trials electronic databases to identify RCTs that compared the effects of initially different calorie intake in critical illness. The primary outcome was overall mortality.

Results:

This meta-analysis included 17 RCTs with a total of 3,593 participants. The result of analysis showed that there was no significant difference between the LC group and HC group in overall mortality (risk ratio [RR], 0.98; 95% confidence interval [CI], 0.87–1.10; P = 0.74; I² = 6%; P = 0.38), or new-onset pneumonia (RR, 0.92; 95% CI, 0.73–1.16, P = 0.46; I² = 38%, P = 0. 11).

Conclusion:

The current meta-analysis showed that there was no significant difference in mortality of critically ill patients initially between the two groups.

WITHDRAWN: Early enteral nutrition versus late enteral nutrition for burns patients: A systematic review and meta-analysis

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Gastric residual volume management in critically ill mechanically ventilated patients: A literature review

Measured gastric residual volume (GRV) is most commonly used as a marker to guide enteral feeding rate and prevention of pulmonary aspiration in gastric-fed, mechanically ventilated intensive care unit patients. However, there is little consensus on the practice standard, and controversies exist regarding its implications.

A total of 17 papers were reviewed to evaluate the factors affecting the accuracy of GRV measurement, GRV measurement practices, and its correlations with clinically important complications. Multiple factors affect the accuracy of GRV measurement. GRV threshold and assessment frequency remain undefined. No direct correlation between measured GRV and incidences of pulmonary aspiration or pneumonia was found. However, higher incidences of pulmonary aspiration were observed in cases of higher GRV.

Not measuring GRV could result in patient harm. Reducing GRV prior to position change and procedures associated with high risk for regurgitation could prevent aspiration incidences.

Jordanian intensive care nurses' perspectives on evidence-based practice in nutritional care

This study aimed to explore Jordanian nurses' perspectives on the implementation of evidence-based practice and team-working related to nutritional care in the critically ill. Poor adherence to evidence-based practice and poor collaboration may contribute to nutritional failure. Fourteen critical care nurses from three healthcare sectors in Jordan were selected purposively and interviewed using semi-structured interviews. The information obtained was subjected to a thematic analysis. Four themes emerged from the study: 'undertaking nutritional responsibilities', 'approaching evidence-based practice', 'multidisciplinary team working' and 'consequences of enteral nutrition care deficits'. Although evidence-based practice was emphasised by nurses, lack of evidence-based resources, and ineffective aspiration reduction measures were found to impede adherence to evidence-based practice. Multidisciplinary team working was introduced as means to improve practice. However, ineffective nursing involvement and poor interaction were obstacles to effective sharing.

Metabolic and nutritional support of critically ill patients: consensus and controversies

The results of recent large-scale clinical trials have led us to review our understanding of the metabolic response to stress and the most appropriate means of managing nutrition in critically ill patients. This review presents an update in this field, identifying and discussing a number of areas for which consensus has been reached and others where controversy remains and presenting areas for future research. We discuss optimal calorie and protein intake, the incidence and management of re-feeding syndrome, the role of gastric residual volume monitoring, the place of supplemental parenteral nutrition when enteral feeding is deemed insufficient, the role of indirect calorimetry, and potential indications for several pharmaconutrients.

Why critically ill patients are protein deprived

Critical illness dramatically increases muscle proteolysis and more than doubles the dietary protein requirement. Yet surprisingly, most critically ill patients receive less than half the recommended amount of protein during their stay in a modern intensive care unit. What could explain the wide gap between the recommendations in clinical care guidelines and actual clinical practice? We suggest that an important aspect of the problem is the failure of guidelines to explain the pathophysiology of protein-energy malnutrition and the ways critical illness modifies protein metabolism. The difficulty created by the lack of a framework for reasoning about appropriate protein provision in critical illness is compounded by the many ambiguous and often contradictory ways the word malnutrition is used in the critical care literature. Failing to elucidate these matters, the recommendations for protein provision in the guidelines are incoherent, unconvincing, and easy to ignore.

Endoscopic clip-assisted feeding tube placement reduces repeat endoscopy rate: results from a randomized controlled trial

OBJECTIVES

To determine whether endoscopic clip-assisted nasoenteral feeding tube placement is more effective than standard feeding tube placement with transnasal endoscopy.

METHODS

Between August 2009 and February 2011, 143 patients referred for endoscopic nasoenteral feeding tube placement were randomized between clip-assisted and standard nasoenteral tube placement. Endoscopies were performed in the endoscopy unit and intensive care unit in a tertiary referral center in the Netherlands. For the clip-assisted procedure, the feeding tube was introduced with a suture fixed to the tip, picked up in the stomach with an endoclip and attached (as distal as possible) to the duodenal wall. In the standard group, a guide wire was placed in the duodenum using a transnasal endoscope, followed by blind insertion of a feeding tube over the guide wire. Primary end point was a repeat endoscopy for incorrect tube placement or spontaneous retrograde tube migration. Secondary end points were incorrect tube placement, spontaneous migration of feeding tube, directs medical costs, and procedure-related (serious) adverse event (SAE).

RESULTS

Of the 143 patients included, 71 were randomly assigned to clip-assisted tube placement, and 72 to standard tube placement. Four (5.6%) repeat endoscopies were performed in the clip-assisted group vs. 19 (26.4%) in the standard group (relative risk reduction (RRR) 0.79; 95% confidence interval (CI) 0.40-0.92). The number needed to clip to avoid one repeat endoscopy was 4.8 (95% CI 3.1-11.3). Repeat endoscopies were mostly performed for incorrectly placed tubes, 3 (4.2%) in the clip-assisted group vs. 16 (22.2%, RRR 0.81; 95% CI 0.38-0.94) in the standard group. Spontaneous retrograde tube migration occurred in one (1.4%) clip-assisted placement and three (4.2%) standard tubes. Median costs were higher for clip-assisted tube placement (€519 vs. €423, P<0.01). Four (5.6%) SAEs occurred after clip-assisted feeding tube placement vs. one (1.4%) after standard feeding tube placement (P=0.21).

CONCLUSIONS

Clip-assisted endoscopic nasoenteral feeding tube placement results in fewer repeat endoscopies than standard endoscopic nasoenteral tube placement, due to a higher success rate of initial placement. When tubes are adequately placed, retrograde tube migration rarely occurs.

Motility disorders of the upper gastrointestinal tract in the intensive care unit: pathophysiology and contemporary management

Upper gastrointestinal (GI) dysmotility, an entity commonly found in the intensive care unit setting, can lead to insufficient nutrient intake while increasing the risk of infection and mortality. Further, overcoming the altered motility with early enteral feeding is associated with a reduced incidence of infectious complications in intensive care unit patients. Upper GI dysmotility in critical care patients is a common occurrence, and there are many causes for this problem, which affects a very heterogenous population with a multitude of underlying medical abnormalities. Therefore, it is of utmost importance to identify this widespread problem and subsequently institute a proper therapy as rapidly as possible. Prokinetic pharmacotherapies are currently the mainstay for the management of disordered upper GI motility. Future therapies, aimed at the underlying pathophysiology of this complex problem, are under investigation. These aim is to reduce the side effects of the currently available options, while improving on nutrition delivery in the critically ill. This review discusses the pathophysiology, clinical manifestations, diagnosis, and treatment of upper GI motility disturbances in the critically ill.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): indications, timing and routes of nutrient delivery]

This article discusses basic features of nutritional support in critically-ill patients: general indications, the route of administration and the optimal timing for the introduction of feeding. Although these features form the bedrock of nutritional support, most of the questions related to these issues are lacking answers based on the highest grade of evidence. Moreover, prospective randomized trials that might elucidate some o f these questions would probably be incompatible with good clinical practice. Nevertheless, nutritional support in critically-ill patients unable to voluntarily meet their own nutritional requirements is currently an unquestionable part of their treatment and care and is essential to the successful management of their illness.

Association between illness severity and timing of initial enteral feeding in critically ill patients: a retrospective observational study

Background

Early enteral nutrition is recommended in cases of critical illness. It is unclear whether this recommendation is of most benefit to extremely ill patients. We aim to determine the association between illness severity and commencement of enteral feeding.

Methods

One hundred and eight critically ill patients were grouped as “less severe” and “more severe” for this cross-sectional, retrospective observational study. The cut off value was based on Acute Physiology and Chronic Health Evaluation II score 20. Patients who received enteral feeding within 48 h of medical intensive care unit (ICU) admission were considered early feeding cases otherwise they were assessed as late feeding cases. Feeding complications (gastric retention/vomiting/diarrhea/gastrointestinal bleeding), length of ICU stay, length of hospital stay, ventilator-associated pneumonia, hospital mortality, nutritional intake, serum albumin, serum prealbumin, nitrogen balance (NB), and 24-h urinary urea nitrogen data were collected over 21 days.

Results

There were no differences in measured outcomes between early and late feedings for less severely ill patients. Among more severely ill patients, however, the early feeding group showed improved serum albumin (p = 0.036) and prealbumin (p = 0.014) but worsened NB (p = 0.01), more feeding complications (p = 0.005), and prolonged ICU stays (p = 0.005) compared to their late feeding counterparts.

Conclusions

There is a significant association between severity of illness and timing of enteral feeding initiation. In more severe illness, early feeding was associated with improved nutritional outcomes, while late feeding was associated with reduced feeding complications and length of ICU stay. However, the feeding complications of more severely ill early feeders can be handled without significantly affecting nutritional intake and there is no eventual difference in length of hospital stay or mortality between groups. Consequently, early feeding shows to be a more beneficial nutritional intervention option than late feeding in patients with more severe illness.

Alternatives to prokinetics to move the pylorus and colon

PURPOSE OF REVIEW

Gastrointestinal motility disorders (GMDs) are common in the ICU. When encountering these problems, one typically thinks of prokinetics. This review summarizes current evidence of treatments.

RECENT FINDINGS

Prokinetics are not the first-line therapy for GMDs. In fact, the clinical implications of using prokinetic agents are rather controversial. Current evidence on alternative treatment modalities such as fluid and electrolyte management, laxatives, opioid antagonists, purgative enemas, acupuncture, physical therapies and probiotics is growing.

SUMMARY

Current state of the art to treat GMDs is primarily focused at the elimination of underlying trigger factors. Fluid and electrolyte management as well as laxatives and peripherally acting μ-opioid receptor antagonists are the recommended first-line therapies that can be complemented with prokinetics. Acupuncture as well as physical modalities, such as massage or warming of the abdomen, is promising with few side-effects and should be considered as well.

Early enteral nutrition reduces mortality in trauma patients requiring intensive care: a meta-analysis of randomised controlled trials

INTRODUCTION

To determine whether the provision of early standard enteral nutrition (EN) confers treatment benefits to adult trauma patients who require intensive care.

MATERIALS AND METHODS

MEDLINE and EMBASE were searched. Hand citation review of retrieved guidelines and systematic reviews was undertaken and academic and industry experts were contacted. Methodologically sound randomised controlled trials (RCTs) conducted in adult trauma patients requiring intensive care that compared the delivery of standard EN, provided within 24 h of injury, to standard care were included.The primary analysis was conducted on clinically meaningful patient-oriented outcomes, which included mortality, functional status and quality of life. Secondary analyses considered vomiting/regurgitation, pneumonia, bacteraemia, sepsis and multiple organ dysfunction syndrome. Meta-analysis was conducted using an analytical method known to minimise bias in the presence of sparse events. The impact of heterogeneity was assessed using the I2 metric.

RESULTS

Three RCTs with 126 participants were found to be free from major flaws and were included in the primary analysis. The provision of early EN was associated with a significant reduction in mortality(OR = 0.20, 95% confidence interval 0.04–0.91, I2 = 0). No other outcomes could be pooled. A sensitivity analysis and a confirmatory analysis conducted using a different analytical method 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 and trial size was small. The results of this meta-analysis should be confirmed by the conduct of a large multi-center trial.