Is refeeding syndrome relevant for critically ill patients?

Considerations for medical nutrition therapy management of the critically ill patient with hematological malignancies: A narrative review

Patients with hematological malignancies (HMs) are more frequently admitted now than in the past to the intensive care unit (ICU) due to more aggressive approaches in primary therapy of HMs and the need for critical care support. Pathophysiological alterations derived from HMs and the different hematological therapies, such as chemotherapy, negatively affect gastrointestinal (GI) function, metabolism, and nutrition status. Further, malnutrition strongly influences outcomes and tolerance of the different hematological therapies. In consequence, these critically ill patients frequently present with malnutrition and pathophysiological alterations that create challenges for the delivery of medical nutrition therapy (MNT) in the ICU. Frequent screening, gauging tolerance, and monitoring nutrition status are mandatory to provide individualized MNT and achieve nutrition objectives. The present review discusses how HM impact GI function and nutrition status, the importance of MNT in patients with HM, and specific considerations for guidance in providing adequate MNT to these patients when admitted to the ICU.

Prevalence, predictive factors, and outcomes of refeeding syndrome among medically critically ill patients: A retrospective cohort study

BACKGROUND

Refeeding syndrome (RFS) is a life-threatening metabolic derangement occurring when nutrition is reintroduced after prolonged starvation. Limited data exist regarding RFS prevalence, risk factors, and outcome, particularly in critically ill patients.

METHODS

A retrospective cohort study was conducted in a medical intensive care unit from June 2018 to August 2020. RFS diagnostic criteria from the National Institute for Health and Care Excellence (NICE) and the American Society for Parenteral and Enteral Nutrition (ASPEN) were used. The primary outcome was 30-day mortality.

RESULTS

Among 216 patients, RFS was diagnosed in 22.7% and 27.3% of patients per the NICE and ASPEN criteria, respectively. There was no significant difference in 30-day mortality between patients with and without RFS (22/59 [37.3%] vs 53/157 [33.8%]; P = 0.627). Independent predictors of RFS were malignancy (odds ratio [OR] = 2.09; 95% CI = 1.06-4.15; P = 0.035), septic shock (OR = 2.26; 95% CI = 1.17-4.39; P = 0.016), and high NICE RFS risk classification (OR = 2.52; 95% CI = 1.20-5.31; P = 0.015). Factors associated with reduced RFS risk were Sequential Organ Failure Assessment (SOFA) scores >12 (OR = 0.45; 95% CI = 0.23-0.88; P = 0.020) and high-dose vasopressor treatment (OR = 0.34; 95% CI = 0.14-0.79; P = 0.012).

CONCLUSION

RFS affected one-fourth of the critically ill patients but did not significantly impact 30-day mortality. Malignancy, septic shock, and high NICE RFS risk classification were positively associated with RFS, whereas high SOFA scores and extensive vasopressor use were linked to decreased risk.

Smartfeeding: A Dynamic Strategy to Increase Nutritional Efficiency in Critically Ill Patients-Positioning Document of the Metabolism and Nutrition Working Group and the Early Mobilization Working Group of the Catalan Society of Intensive and Critical Care Medicine (SOCMiC)

Adequate medical nutrition therapy for critically ill patients has an impact on their prognoses. However, it requires an individualized approach that takes into account the activity (phases of metabolic stress) and particularity of these patients. We propose a comprehensive strategy considering the patients' nutritional status and the set of modifiable circumstances in these patients, in order to optimize/support nutritional efficiency: (1) A detailed anamnesis and an adequate initial nutritional assessment must be performed in order to implement medical nutrition therapy that is in line with the needs and characteristics of each patient. Furthermore, risks associated with refeeding syndrome, nutritrauma or gastrointestinal dysfunction must be considered and prevented. (2) A safe transition between nutrition therapy routes and between health care units will greatly contribute to recovery. The main objective is to preserve lean mass in critically ill patients, considering metabolic factors, adequate protein intake and muscle stimulation. (3) Continuous monitoring is required for the successful implementation of any health strategy. We lack precise tools for calculating nutritional efficiency in critically ill patients, therefore thorough monitoring of the process is essential. (4) The medical nutrition approach in critically ill patients is multidisciplinary and requires the participation of the entire team involved. A comprehensive strategy such as this can make a significant difference in the functional recovery of critically ill patients, but leaders must be identified to promote training, evaluation, analysis and feedback as essential components of its implementation, and to coordinate this process with the recognition of hospital management.

The science of micronutrients in clinical practice - Report on the ESPEN symposium

BACKGROUND & AIMS

The European Society for Clinical Nutrition and Metabolism published its first clinical guidelines for use of micronutrients (MNs) in 2022. A two-day web symposium was organized in November 2022 discussing how to apply the guidelines in clinical practice. The present paper reports the main findings of this symposium.

METHODS

Current evidence was discussed, the first day being devoted to clarifying the biology underlying the guidelines, especially regarding the definition of deficiency, the impact of inflammation, and the roles in antioxidant defences and immunity. The second day focused on clinical situations with high prevalence of MN depletion and deficiency.

RESULTS

The importance of the determination of MN status in patients at risk and diagnosis of deficiencies is still insufficiently perceived, considering the essential role of MNs in immune and antioxidant defences. Epidemiological data show that deficiencies of several MNs (iron, iodine, vitamin D) are a global problem that affects human health and well-being including immune responses such as to vaccination. Clinical conditions frequently associated with MN deficiencies were discussed including cancer, obesity with impact of bariatric surgery, diseases of the gastrointestinal tract, critical illness, and aging. In all these conditions, MN deficiency is associated with worsening of outcomes. The recurrent problem of shortage of MN products, but also lack of individual MN-products is a worldwide problem.

CONCLUSION

Despite important progress in epidemiology and clinical nutrition, numerous gaps in practice persist. MN depletion and deficiency are frequently insufficiently searched for in clinical conditions, leading to inadequate treatment. The symposium concluded that more research and continued education are required to improve patient outcome.

Impact of Nutritional Management on Survival of Critically Ill Malnourished Patients with Refeeding Hypophosphatemia

BACKGROUND

Early nutritional therapy may aggravate hypophosphatemia in critically ill patients.

AIM

To investigate the influence of the type nutritional therapy on the survival of critically-ill malnourished patients at refeeding hypophosphatemia risk.

METHODS

Retrospective cohort study including malnourished, critically-ill adults, admitted from June 2014-December 2017 in an intensive care unit (ICU) at a tertiary hospital. Refeeding hypophosphatemia risk was defined as low serum phosphorus levels (<2.5 mg/dL) seen at two timepoints: before the initiation and at day 4 of the nutritional therapy. Patients receiving enteral nutrition (EN) were compared with those receiving supplemental parenteral nutrition (SPN-EN plus parenteral nutrition). Primary outcome was 60 d survival. Secondary endpoint was the incidence of refeeding hypophosphatemia risk.

RESULTS

We included 468-321 patients (68.6%) received EN and 147 (31.4%) received SPN. The mortality rate was 36.3% (n = 170). Refeeding hypophosphatemia risk was found in 116 (24.8%) patients before and in 177 (37.8%) at day 4 of nutritional therapy. The 60 d mean survival probability was greater for patients receiving SPN both before (42.4 vs. 22.4%, p = 0.005) and at day 4 (37.4 vs. 25.8%, p = 0.014) vs. patients receiving EN at the same timepoints. Cox regression showed a hazard ratio of 3.3 and 2.4 for patients at refeeding hypophosphatemia risk before and at day 4 of EN, respectively, compared to the SPN group at the same timepoints.

CONCLUSION

Refeeding hypophosphatemia risk was frequent in malnourished ICU patients and the survival for patients receiving SPN seemed associated with better survival than EN only.

Development and validation of risk prediction model for refeeding syndrome in neurocritical patients

Background

The incidence of refeeding syndrome (RFS) in critically ill patients is high, which is detrimental to their prognoses. However, the current status and risk factors for the occurrence of RFS in neurocritical patients remain unclear. Elucidating these aspects may provide a theoretical basis for screening populations at high risk of RFS.

Methods

A total of 357 patients from January 2021 to May 2022 in a neurosurgery ICU of a tertiary hospital in China were included using convenience sampling. Patients were divided into RFS and non-RFS groups, based on the occurrence of refeeding-associated hypophosphatemia. Risk factors for RFS were determined using univariate and logistic regression analyses, and a risk prediction model for RFS in neurocritical patients was developed. The Hosmer-Lemeshow test was used to determine the goodness of fit of the model, and the receiver operator characteristic curve was used to examine its discriminant validity.

Results

The incidence of RFS in neurocritical patients receiving enteral nutrition was 28.57%. Logistic regression analyses showed that history of alcoholism, fasting hours, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, Sequential Organ Failure Assessment (SOFA) scores, low serum albumin, and low baseline serum potassium were risk factors of RFS in neurocritical patients (p < 0.05). The Hosmer-Lemeshow test showed p = 0.616, and the area under the ROC curve was 0.791 (95% confidence interval: 0.745-0.832). The optimal critical value was 0.299, the sensitivity was 74.4%, the specificity was 77.7%, and the Youden index was 0.492.

Conclusion

The incidence of RFS in neurocritical patients was high, and the risk factors were diverse. The risk prediction model in this study had good predictive effects and clinical utility, which may provide a reference for assessing and screening for RFS risk in neurocritical patients.

When is parenteral nutrition indicated?

The indications and contraindications of parenteral nutrition (PN) are discussed in view of recent clinical findings. For decades, PN has been restricted to patients unable to tolerate enteral nutrition (EN) intake owing to the perceived risk of severe side-effects. The evolution of the PN substrate composition and delivery of nutrition via all-in-one bags has dramatically improved the application prospects of PN. Recent studies show similar complication rates of nutrition therapy administered through enteral and intravenous routes. Therefore, indications of PN have, based on evidence, extended beyond complete gastrointestinal (GI) failure to include conditions such as insufficient EN generating persistent negative energy balance and insufficient protein intakes, malabsorption, or specific needs that are impossible to cover with EN feeds.

Incidence of Refeeding Syndrome in Critically Ill Children With Nutritional Support

INTRODUCTION

Early enteral nutrition is recommended for critically ill children, potentially exposing those who are undernourished to the risk of refeeding syndrome. However, data on its incidence is lacking, and the heterogeneity of diagnostic criteria and frequent electrolyte disorders in this population make its diagnosis complex. In 2020, the American Society for Parenteral and Enteral Nutrition (ASPEN) developed consensus recommendations for identifying patients at risk and with refeeding syndrome. These state that undernourished children are considered at risk of refeeding syndrome; those who develop one significant electrolyte disorder (decrease ≥ 10% in phosphorus, potassium, and/or magnesium) within the first five days of nutritional support, combined with a significant increase in energy intake, are considered to have refeeding syndrome. The aim of this study was to determine the incidence of refeeding syndrome according to the ASPEN definition in critically ill children on nutritional support.

MATERIALS AND METHODS

A secondary analysis of two prospective cohorts conducted in a tertiary pediatric intensive care unit in France was undertaken, and additional data were retrospectively collected. Children included were those (0-18 years) admitted to the pediatric intensive care unit with a minimum of one phosphorus, potassium, and/or magnesium assay and who received exclusive or supplemental nutritional support. Undernourished children (body mass index z-score < -2 standard deviations) were considered at risk of refeeding syndrome. The ASPEN critiera were used to identify those with probable refeeding syndrome.

RESULTS

A total of 1,261 children were included in the study, with 199 children (15.8%) classified as undernourished, who were at risk of refeeding syndrome. Of these, 93 children were identified as having probable refeeding syndrome, giving an overall incidence of 7.4%. The incidence rate among at-risk children was 46.7%. Most patients (58.1%) were classified as having severe refeeding syndrome.

CONCLUSION

Refeeding syndrome remains difficult to diagnose in critically ill children, due to frequent confounding factors impacting electrolyte plasma levels. These findings suggest that refeeding syndrome incidence may be high in undernourished children, and that refeeding syndromes can be severe. Further prospective studies using the ASPEN definition and risk criteria are required.

A guide to enteral nutrition in intensive care units: 10 expert tips for the daily practice

The preferential use of the oral/enteral route in critically ill patients over gut rest is uniformly recommended and applied. This article provides practical guidance on enteral nutrition in compliance with recent American and European guidelines. Low-dose enteral nutrition can be safely started within 48 h after admission, even during treatment with small or moderate doses of vasopressor agents. A percutaneous access should be used when enteral nutrition is anticipated for ≥ 4 weeks. Energy delivery should not be calculated to match energy expenditure before day 4–7, and the use of energy-dense formulas can be restricted to cases of inability to tolerate full-volume isocaloric enteral nutrition or to patients who require fluid restriction. Low-dose protein (max 0.8 g/kg/day) can be provided during the early phase of critical illness, while a protein target of > 1.2 g/kg/day could be considered during the rehabilitation phase. The occurrence of refeeding syndrome should be assessed by daily measurement of plasma phosphate, and a phosphate drop of 30% should be managed by reduction of enteral feeding rate and high-dose thiamine. Vomiting and increased gastric residual volume may indicate gastric intolerance, while sudden abdominal pain, distension, gastrointestinal paralysis, or rising abdominal pressure may indicate lower gastrointestinal intolerance.

Parenteral Provision of Micronutrients to Pediatric Patients: An International Expert Consensus Paper

INTRODUCTION

Micronutrients (vitamins and trace elements) are essential to all nutrition. For children and neonates who are dependent upon nutrition support therapies for growth and development, the prescribed regimen must supply all essential components. This paper aims to facilitate interpretation of existing clinical guidelines into practical approaches for the provision of micronutrients in pediatric parenteral nutrition.

METHODS

An international, interdisciplinary expert panel was convened to review recent evidence-based guidelines and published literature to develop consensus-based recommendations on practical micronutrient provision in pediatric parenteral nutrition.

RESULTS

The guidelines and evidence have been interpreted as answers to 10 commonly asked questions around the practical principles for provision and monitoring of micronutrients in pediatric patients.

CONCLUSION

Micronutrients are an essential part of all parenteral nutrition and should be included in the pediatric nutrition therapy care plan.

Hypophosphatemia and risk of refeeding syndrome in critically ill patients before and after nutritional therapy

OBJECTIVE

To investigate the prevalence of hypophosphatemia as a marker of refeeding syndrome (RFS) before and after the start of nutritional therapy (NT) in critically ill patients.

METHODS

Retrospective cohort study including 917 adult patients admitted at the intensive care unit (ICU) of a tertiary hospital in Cuiabá-MT/Brasil. We assessed the frequency of hypophosphatemia (phosphorus <2.5mg/dl) as a risk marker for RFS. Serum phosphorus levels were measured and compared at admission (P1) and after the start of NT (P2).

RESULTS

We observed a significant increase (36.3%) of hypophosphatemia and, consequently, a greater risk of RFS from P1 to P2 (25.6 vs 34.9%; p<0.001). After the start of NT, malnourished patients had a greater fall of serum phosphorus. Patients receiving NT had an approximately 1.5 times greater risk of developing RFS (OR= 1.44 95%CI 1.10-1,89; p= 0.01) when compared to those who received an oral diet. Parenteral nutrition was more associated with hypophosphatemia than either enteral nutrition (p=0,001) or parenteral nutrition supplemented with enteral nutrition (p=0,002).

CONCLUSION

The frequency of critically ill patients with hypophosphatemia and at risk for RFS on admission is high and this risk increases after the start of NT, especially in malnourished patients and those receiving parenteral nutrition.

Mortality associated with new risk classification of developing refeeding syndrome in critically ill patients: A cohort study

BACKGROUND & AIMS

Although refeeding syndrome (RFS) has been recognized as a potentially fatal metabolic complication, the definition of RFS has remained unclear. Recently, European researchers suggested an evidence-based and consensus-supported algorithm that consisted of a new RFS risk classification and treatment strategies for medical inpatients. The classification was based on the National Institute for Health and Clinical Excellence (NICE) criteria for patients at risk of developing RFS. In this study, we aimed to investigate the frequency of each applied new risk group and the association between the new classification and mortality in critically ill patients.

METHODS

This cohort study was conducted at a Japanese metropolitan tertiary-care university hospital from December 2016 to December 2018. We included critically ill adult patients who were admitted to the intensive care unit (ICU) via the emergency department and who stayed in the ICU for 24 h or longer. We applied the new risk classification based on the NICE RFS risk factors on ICU admission. The main exposure was risk classification of RFS: no risk, low risk, high risk, or very high risk. The primary outcome was in-hospital mortality censored at day 30 after ICU admission. We performed a multivariable analysis using Cox proportional hazard regression.

RESULTS

We analyzed 542 patients who met the eligibility criteria. The prevalence of the four RFS risk classification groups was 25.8% for no risk, 25.7% for low risk, 46.5% for high risk, and 2.0% for very high risk. The 30-day mortality was 5.0%, 7.2%, 16.3%, and 27.3%, respectively (log-rank trend test: p < 0.001). In the multivariable Cox regression, adjusted hazard ratios with no risk group as a reference were 1.28 (95% CI 0.48-3.38) for low risk, 2.81 (95% CI 1.24-6.35) for high risk, and 3.17 (95% CI 0.78-12.91) for very high risk.

CONCLUSIONS

Approximately half the critically ill patients were categorized as high or very high risk based on the new risk classification. Furthermore, as the risk categories progressed, the 30-day in-hospital mortality increased. Early recognition of patients at risk of developing RFS may improve patient outcomes through timely and optimal nutritional treatment.

Monitoring and parenteral administration of micronutrients, phosphate and magnesium in critically ill patients: The VITA-TRACE survey

BACKGROUND & AIMS

Despite the presumed importance of preventing and treating micronutrient and mineral deficiencies, it is still not clear how to optimize measurement and administration in critically ill patients. In order to design future comparative trials aimed at optimizing micronutrient and mineral management, an important first step is to gain insight in the current practice of micronutrient, phosphate and magnesium monitoring and administration.

METHODS

Within the metabolism-endocrinology-nutrition (MEN) section of the European Society of Intensive Care Medicine (ESICM), the micronutrient working group designed a survey addressing current practice in parenteral micronutrient and mineral administration and monitoring. Invitations were sent by the ESICM research department to all ESICM members and past members.

RESULTS

Three hundred thirty-four respondents completed the survey, predominantly consisting of physicians (321 [96.1%]) and participants working in Europe (262 [78.4%]). Eighty-one (24.3%) respondents reported to monitor micronutrient deficiencies through clinical signs and/or laboratory abnormalities, and 148 (44.3%) reportedly measure blood micronutrient concentrations on a routine basis. Two hundred ninety-two (87.4%) participants provided specific data on parenteral micronutrient supplementation, of whom 150 (51.4%) reported early administration of combined multivitamin and trace element preparations at least in selected patients. Among specific parenteral micronutrient preparations, thiamine (146 [50.0%]) was reported to be the most frequently administered micronutrient, followed by vitamin B complex (104 [35.6%]) and folic acid (86 [29.5%]). One hundred twenty (35.9%) and 113 (33.8%) participants reported to perform daily measurements of phosphate and magnesium, respectively, whereas 173 (59.2%) and 185 (63.4%) reported to routinely supplement these minerals parenterally.

CONCLUSION

The survey revealed a wide variation in current practices of micronutrient, phosphate and magnesium measurement and parenteral administration, suggesting a risk of insufficient prevention, diagnosis and treatment of deficiencies. These results provide the context for future comparative studies, and identify areas for knowledge translation and recommendations.

Refeeding syndrome in hematological cancer patients - current approach

Introduction: According to estimates based on the GLOBOCAN database of the International Agency for Research on Cancer, in 2018 alone, 18 100 000 cancers were globally diagnosed. Importantly, the majority of cancer patients experience unintended weight loss that leads to many adverse clinical consequences, including malnutrition and cancer cachexia. At the same time, each nutritional intervention must be carried out individually, as it can lead to critical complications, resulting in a threat to the health and life of the cachectic patient. An example of this type of risk is refeeding syndrome.Areas covered: Three factors seem to be crucial in this case: early identification of patients at risk of malnutrition, the introduction of an individualized diet regimen and constant monitoring of nutritional intervention. It seems equally important to spread awareness about the possibility of refeeding syndrome and knowledge about its patomechanisms and consequences among medical staff. This should lead to minimizing the risk of refeeding syndrome.Expert opinion: It should be noted that current guidelines on the pathogenesis, risk factors and methods of prevention and treatment of refeeding syndrome require further modifications, that would harmonize the management regimen in both prevention and therapy of refeeding syndrome.

Risk of refeeding syndrome. Case report

Introduction: Refeeding syndrome is an acute metabolic disorder that occurs during nutritional repletion. Although it has been known for years, the early detection of risk factors for its onset and the implementation of measures to prevent it are not common in nutritional care.Case presentation: 48-year-old male patient, in critical care for 6 days, with suspected Wernicke-Korsakoff encephalopathy and high risk of refeeding syndrome according to criteria of the National Institute of Health and Clinical Excellence. The subject received enteral nutrition with 14 kcal/kg for the first 3 days, with subsequent increases aiming to achieve a nutritional goal of 25 kcal/kg on day 5.  He also received daily supplementation of thiamine 600mg, folic acid 5mg and pyridoxine 50mg. Blood phosphorus decreased from 3 mg/dL to 2 mg/dL the day after initiating the nutritional plan and normalized by day 3.Discussion: The patient did not present severe hypophosphatemia or clinical manifestations of refeeding syndrome. Hypophosphatemia was resolved by maintaining a stable caloric restriction during the first days. Some professionals consider this restriction as very conservative, and others think that it may lead to achieve significant improvements in mortality reduction.Conclusions: The strategy for assessing the risk of refeeding syndrome, nutritional management and implemented follow-up were successful in preventing the patient from developing a refeeding syndrome.