Review of the refeeding syndrome

Home Initiation of Parenteral Nutrition

Parenteral nutrition (PN) has been successfully initiated in the home since the early 1990s. The American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) Standards for Specialized Nutrition Support: Home Care Patients, Safe Practices for Parenteral Nutrition, and Guidelines for the Use of Parenteral and Enteral Nutrition in Adult and Pediatric Patients do not contain specific information on the initiation of home PN (HPN). Peer-reviewed, published guidelines are necessary to provide safe and appropriate initiation of HPN. Certain patients should not have PN initiated in the home, such as those with organ failure, uncontrolled diabetes, or uncorrectable electrolyte abnormalities. Excellent candidates for initiation of HPN include patients who have failed enteral feedings, have gastrointestinal (GI) diseases without excessive GI losses, or those with an oncology diagnosis and inability to tube feed. One concern of initiation of HPN is the potential for refeeding syndrome. Refeeding syndrome can be prevented when patients are properly evaluated and managed before initiation of PN. Refeeding syndrome can be avoided by rehydration with fluid and electrolytes before initiation of HPN to normalize blood chemistry when necessary and by starting with a moderate-volume, low-carbohydrate HPN solution compounded with optimal potassium, phosphorus, and magnesium content, and slowly advanced to goal. The "start low and go slow" motto of nutrition support should continue to be followed, but more specific guidelines are needed to assist nutrition support clinicians with safe and appropriate initiation of HPN.

ASPEN Safe Practices for Enteral Nutrition Therapy [Formula: see text]

Enteral nutrition (EN) is a valuable clinical intervention for patients of all ages in a variety of care settings. Along with its many outcome benefits come the potential for adverse effects. These safety issues are the result of clinical complications and of process-related errors. The latter can occur at any step from patient assessment, prescribing, and order review, to product selection, labeling, and administration. To maximize the benefits of EN while minimizing adverse events requires that a systematic approach of care be in place. This includes open communication, standardization, and incorporation of best practices into the EN process. This document provides recommendations based on the available evidence and expert consensus for safe practices, across each step of the process, for all those involved in caring for patients receiving EN.

Nasogastric Tube Feeding for Individuals With Anorexia Nervosa: An Integrative Review

BACKGROUND

The use of nasogastric (NG) feeding in individuals with anorexia nervosa (AN) is endorsed by national professional organizations; however, no guidelines currently exist.

OBJECTIVES

The objectives of this review were to identify and evaluate outcomes of NG feedings for individuals with AN and to develop recommendations for future research, policy, and practice.

DESIGN

An integrative review of the research literature was conducted.

RESULTS

Of the 19 studies reviewed, all indicated short-term weight gain following NG feeding. Four studies examined adherence; nearly 30% of subjects were nonadherent as evidenced by tube manipulation. Seven studies reported psychiatric outcomes, suggesting NG feeding reduces eating disorder behaviors but not overall symptomology.

CONCLUSIONS

NG feeding promotes short-term weight gain; however, long-term outcomes are poorly understood. Future research, using rigorous methods, is still needed to inform practice.

Neuromuscular signs associated with acute hypophosphatemia in a dog

The purpose of this report was to describe the successful recognition and management of neuromuscular dysfunction secondary to severe, acute hypophosphatemia in an adult dog with a 2 day history of vomiting, anorexia, and abdominal pain. Radiographs were suggestive of a foreign body obstruction, and surgery was recommended. Resection and anastomosis of the distal duodenum and proximal jejunum was performed. The dog recovered uneventfully, but approximately 36 hr postoperatively, he was found to have significant weakness and muscle tremors that were accompanied by hyperthermia. The only significant abnormality on a serum biochemical profile was a phosphorous level of 0.26 mmol/L. Within 6 hr of initiating phosphorous supplementation, the patient fully recovered and had no residual signs of neuromuscular dysfunction. Signs of neurologic dysfunction secondary to hypophosphatemia are commonly recognized in human patients. Reports of patients with severe muscle weakness, some of which necessitate ventilation due to weakening of muscles of respiration, are common throughout the literature. Less commonly, tremors are noted. This is the first known report of neuromuscular signs recognized and rapidly corrected in a dog. Although it is likely to be uncommon, hypophosphatemia should be recognized as a differential diagnosis in patients with tremors and/or muscle weakness.

Parenteral Nutrition Basics for the Clinician Caring for the Adult Patient

Parenteral nutrition (PN) is a life-sustaining therapy providing nutrients to individuals with impaired intestinal tract function and enteral access challenges. It is one of the most complex prescriptions written routinely in the hospital and home care settings. This article is to aid the nutrition support clinician in the safe provision of PN, including selecting appropriate patients for PN, vascular access, development of a PN admixture, appropriate therapy monitoring, recognition of preparation options, and awareness of preparation and stability concerns.

Malnutrition in the ICU patient population

Malnutrition has been identified as a cause for disease as well as a condition resulting from inflammation associated with acute or chronic disease. Malnutrition is common in acute-care settings, occurring in 30% to 50% of hospitalized patients. Inflammation has been associated with malnutrition and malnutrition has been associated with compromised immune status, infection, and increased intensive care unit (ICU) and hospital length of stay. The ICU nurse is in the best position to advocate for appropriate nutritional therapies and facilitate the safe delivery of nutrition.

Enteral Nutrition for Adults in the Hospital Setting

In patients unable to tolerate oral intake, multiple options of nutrient delivery are available to the clinician. Administration of enteral nutrition (EN) has long been considered the standard of care for nutrition support among patients unable to meet energy and protein requirements orally. Healthcare practitioners must make careful decisions related to ordering, administering, and monitoring EN therapy. In the hospital setting, the registered dietitian is a key resource in enteral formula selection and method of administration, monitoring for and troubleshooting EN-related complications, and transitioning to oral feeding. The hospital setting also presents many unique challenges in providing optimal nutrition to the enterally fed patient.

Pathophysiology, treatment, and prevention of fluid and electrolyte abnormalities during refeeding syndrome

Refeeding syndrome may occur after the reintroduction of carbohydrates in chronically malnourished or acutely hypermetabolic patients as a result of a rapid shift to glucose utilization as an energy source. Electrolyte abnormalities of phosphorus, potassium, and magnesium occur, leading to complications of various organ systems, and may result in death. Patients should be screened for risk factors of malnutrition to prevent refeeding syndrome. For those at risk, nutrition should be initiated and slowly advanced toward the patient's goal over several days. Electrolyte disturbances should be aggressively corrected.

Potassium toxicity at low serum potassium levels with refeeding syndrome

Refeeding syndrome is a life-threatening condition occurring in severely malnourished patients after initiating feeding. Severe hypophosphatemia with reduced adenosine triphosphate production has been implicated, but little data are available regarding electrolyte abnormalities. In this case, we report electrocardiographic changes consistent with hyperkalemia during potassium replacement after a serum level increase from 1.9 to 2.9 mEq/L. This was reversed by lowering serum potassium back to 2.0 mEq/L. In conclusion, the patient with prolonged malnutrition became adapted to low potassium levels and developed potassium toxicity with replacement.

Phosphorus and calcium: a review for the adult nutrition support clinician

Phosphorus (P) and calcium (Ca) serve vital roles in the human body and are essential components of nutrition support therapy. Regulation of P and regulation of Ca in the body are closely interrelated, and P and Ca homeostasis can be affected by several factors, including disease states, clinical condition, severity of illness, and medications. Nutrition support clinicians must understand these factors to prevent and treat P and Ca disorders in patients receiving nutrition support therapy. This review provides an overview of P and Ca for the adult nutrition support clinician, with some emphasis on the hospitalized inpatient.

Hypophosphatemia is a common complication in severely disabled individuals with neurological disorders and is caused by infection, refeeding and Fanconi syndrome

AIM

To describe the characteristics of hypophosphatemia in severely disabled individuals with neurological disorders and to identify its causative factors.

METHOD

We retrospectively reviewed clinical data from 82 individuals with motor skills classified as sitting, rollover or bedridden. Age, gender and body mass index were compared in individuals with (n=19) and without (n=63) a history of hypophosphatemia (serum phosphate levels <2.0 mg/dl). The clinical course of each patient with hypophosphatemia was reviewed and the cause identified. Laboratory data during hypophosphatemia was compared with that after recovery.

RESULTS

The age, gender and body mass index did not differ significantly between the individuals with and without hypophosphatemia. Nineteen patients experienced 25 episodes of hypophosphatemia. The causes included febrile illnesses (n=17), refeeding syndrome (n=4) and Fanconi syndrome (n=3), but was unidentifiable in one episode. Significant elevations in C-reactive protein levels and reductions in sodium levels were observed during hypophosphatemia episodes.

INTERPRETATION

Hypophosphatemia is a common complication in severely disabled individuals with frequent bacterial infections, refeeding following malnutrition and valproate administration for epilepsy treatment. Because severe hypophosphatemia is life threatening, serum phosphate levels should be closely monitored in this population.

Refeeding syndrome in Southeastern Taiwan: Our experience with 11 cases

AIM: To present our experience with refeeding syndrome in southeastern Taiwan.

METHODS: We conducted a retrospective study during a 2-year period at the Mackay Memorial Hospital, Taitung Branch. We enrolled patients with very little or no nutrition intake for more than 10 d, a high risk group of refeeding syndrome, including those suffering from alcohol abuse, cancerous cachexia, chronic malnutrition, and prolonged starvation.

RESULTS: A total of 11 patients (7 males, 4 females) with nasogastric feeding were included as having refeeding syndrome. Most of them had the symptoms of diarrhea, lethargy, and leg edema. The initial nutritional supplement was found to be relatively high in calories (1355.1 ± 296.2 kcal/d), high in protein (47.3 ± 10.4 gm/d), low in vitamin B1 (2.0 ± 0.5 mg/d), low in potassium (1260.4 ± 297.7 mg/d), and low in phosphorus (660.1 ± 151.8 mg/d). Furthermore, hypophosphatemia (2.4 ± 0.9 mg/dL) was noted during follow-up. Based on the suggestions of a dietician and a gastroenterologist, the clinical disorders of diarrhea, malaise and leg edema were significantly improved. The level of phosphate was also increased (3.3 ± 0.6 mg/dL).

CONCLUSION: Refeeding syndrome is an overlooked and risky disorder that has some potentially fatal complications. Nasogastric feeding in nursing homes is an important risk factor for patients and deserves greater attention based on the initial results of this study.

Refeeding syndrome: screening, incidence, and treatment during parenteral nutrition

The possible deleterious effects of feeding after a period of prolonged starvation have been known for over 60 years. The resultant biochemical disturbance, symptoms, and signs have been termed the refeeding syndrome (RS). The key to the pathophysiology is the stimulation of insulin release resulting in anabolic activity. Depleted electrolyte and micronutrient stores are overwhelmed and cellular function disrupted. A concise definition of RS is not agreed and hampers interpretation of clinical data. Hypophosphatemia and appearance of tissue edema/pathological fluid shifts are the most often agreed diagnostic criteria. The characteristics of particular patient groups at risk have been recognized for some time, and there are guidelines from the National Institute for Clinical Excellence in the UK to aid recognition of individuals at high risk along with protocols for initiating nutrition. Using loose diagnostic criteria, RS appears to occur in 4% of cases of parenteral nutrition (PN) when case records were reviewed by experts in a large study into PN care in the UK. Disappointingly, prescribers recognized only 50% of at risk cases. Early data from a similar study in New Zealand appear to show a similar pattern. Prospective series looking at patients receiving nutrition support in institutions with Nutrition Support Teams have found an incidence of 1-5%. RS is still underrecognized. Patients receiving PN should be counted as being in a high-risk category and feeding protocols to avoid RS applied. Low rates of RS then occur and death from this cause be avoided.

Evaluation of a nutrition rehabilitation protocol in hospitalized adolescents with restrictive eating disorders

PURPOSE

Nutritional rehabilitation is an essential part of inpatient treatment for adolescents with restrictive eating disorders (ED). The purpose of this study was to examine weight gain, prevalence of refeeding syndrome, and nutritional composition of the diet in hospitalized adolescents with anorexia nervosa (AN) and eating disorder not otherwise specified (EDNOS), restrictive type, on a structured nutrition rehabilitation protocol (NRP).

METHODS

An evidence-based NRP was implemented on the inpatient eating disorders unit at the Hospital for Sick Children in June 2011. Adolescents 12-18 years of age with AN or EDNOS, an ideal body weight (IBW) of 70% or greater, no clinical or metabolic signs of refeeding syndrome, and on their first admission were assigned to the NRP. A retrospective chart review between June 2011 and June 2012 was completed. A repeated measures analysis was used to determine the mean rate of weight gain. Mean cumulative % change in body mass index (BMI) was plotted against days to assess daily weight trajectory.

RESULTS

Twenty-nine patients, mean age of 14.7 (SD ± 1.5) years, were included in the study. A total of 3.5% developed hypophosphatemia on day 1. Mean weight gain was .24 kg/day (p < .0001) and 1.7 kg/week. An increase in mean cumulative % change in BMI was observed from days 2-14. Actual caloric intake was 98%-113% of the prescribed intake. Macronutrient distribution was within acceptable limits based on dietary reference intakes.

CONCLUSIONS

The NRP is considered effective, efficient, and safe. Further research is needed to explore the effectiveness and safety of NRPs in other populations.

Survey of current enteral nutrition practices in treatment of amyotrophic lateral sclerosis

BACKGROUND AND AIMS

Enteral nutrition (EN) is commonly prescribed for dysphagia and weight loss in amyotrophic lateral sclerosis (ALS), but there are currently no ALS-specific EN guidelines. We aimed to survey current practices prescribing EN to ALS patients.

METHODS

An online survey was distributed using list servers administered by the Academy of Nutrition and Dietetics (AND), Muscular Dystrophy Association (MDA), and ALS Association (ALSA).

RESULTS

A total of 148 dietitians, nurses, and physicians participated in the survey, of whom 50% were dietitians and 68% were associated with an ALS clinic. Only 47% of respondents reported their patients to be fully compliant with EN recommendations. Side effects (fullness, diarrhea, constipation, and bloating) were the most important reason for patient noncompliance, followed by dependence on caregivers. By contrast, only 3% of providers rated depression/hopelessness as the most important reason for noncompliance. Half of those surveyed reported that more than 25% of patients continued to lose weight after starting EN.

CONCLUSIONS

Our survey results show a high frequency of gastrointestinal side effects and weight loss in ALS patients receiving EN. These findings may be limited by sampling error and non-response bias. Prospective studies are needed to help establish EN guidelines for ALS.

Short bowel syndrome presenting with re-feeding syndrome in a Han Chinese patient: a case report

Introduction

Re-feeding syndrome is common in patients with long-term starvation. To the best of our knowledge this case is the first to report a patient with short bowel syndrome developing re-feeding syndrome 12 years after the bowel resection.

Case presentation

A 33-year-old Chinese Han man underwent small bowel resection leaving only 40 cm of bowel, without an ileocecal valve, 12 years previously. At that time he was weaned from total parenteral nutrition and had a normal diet. He later developed features of severe malnutrition, and when parenteral nutrition was given, he developed re-feeding syndrome.

Conclusion

Although re-feeding syndrome is a common complication in patients with any kind of nutritional support, and known to us for many years, high risk patients still need more attention and monitoring. Re-feeding syndrome in this case was not only a macronutrients deficiency but also a micronutrient deficient, and prompt supplement therapy and organ function support proved to be successful.

Qual é a importância clínica e nutricional da síndrome de realimentação?

INTRODUÇÃO: A síndrome de realimentação caracteriza-se por alterações neurológicas, sintomas respiratórios, arritmias e falência cardíacas, poucos dias após a realimentação. Ocorre em consequência do suporte nutricional (oral, enteral ou parenteral) em pacientes severamente desnutridos. OBJETIVO: Avaliar de suas causas e a aplicação das medidas dietéticas profiláticas apropriadas visando a prevenção e diminuição da morbimortalidade desta condição. MÉTODOS: Foi realizado levantamento bibliográfico na SciELO, LILACS, Medline/Pubmed, Biblioteca Cochrane e sites governamentais nos idiomas português, inglês e espanhol. Os levantamentos foram sobre os últimos 15 anos, selecionando os descritores: síndrome de realimentação, desnutrição, hipofosfatemia, hipocalemia, hipomagnesemia. CONCLUSÃO: O acompanhamento de parâmetros metabólicos e de níveis de eletrólitos antes do início do suporte nutricional e periodicamente durante a alimentação deve ser baseado em protocolos, no estado da doença subjacente e na duração da terapia. Equipe multidisciplinar de terapia nutricional pode orientar e educar outros profissionais de saúde na prevenção, diagnóstico e tratamento dessa síndrome.

A prospective examination of weight gain in hospitalized adolescents with anorexia nervosa on a recommended refeeding protocol

PURPOSE

Current refeeding recommendations for adolescents hospitalized with anorexia nervosa (AN) are conservative, starting with low calories and advancing slowly to avoid refeeding syndrome. The purpose of this study was to examine weight change and clinical outcomes in hospitalized adolescents with AN on a recommended refeeding protocol.

METHODS

Adolescents aged 13.1-20.5 years were followed during hospitalization for AN. Weight, vital signs, electrolytes, and 24-hour fluid balance were measured daily. Percent median body mass index (%MBMI) was calculated as 50th percentile BMI for age and gender. Calories were prescribed on admission and were increased every other day.

RESULTS

Thirty-five subjects with a mean (SD) age of 16.2 (1.9) years participated over 16.7 (6.4) days. Calories increased from 1,205 (289) to 2,668 (387). No subjects had refeeding syndrome; 20% had low serum phosphorus. Percent MBMI increased from 80.1 (11.5) to 84.5 (9.6); overall gain was 2.10 (1.98) kg. However, 83% of subjects initially lost weight. Mean %MBMI did not increase significantly until day 8. Higher calories prescribed at baseline were significantly associated with faster weight gain (p = .003) and shorter hospital stay (p = .030) in multivariate regression models adjusted for %MBMI and lowest heart rate on admission.

CONCLUSIONS

Hospitalized adolescents with AN demonstrated initial weight loss and slow weight gain on a recommended refeeding protocol. Higher calorie diets instituted at admission predicted faster weight gain and shorter hospital stay. These findings support the development of more aggressive feeding strategies in adolescents hospitalized with AN. Further research is needed to identify caloric and supplementation regimens to maximize weight gain safely while avoiding refeeding syndrome.

Refeeding syndrome in a cat with hepatic lipidosis

Refeeding syndrome is characterized by severe hypophosphatemia occurring in patients given enteral or parenteral nutrition after severe weight loss. There are few veterinary reports that describe this syndrome but it is well documented in human medicine. This report describes a case of a domestic shorthair cat diagnosed with hepatic lipidosis following a 4-week history of decreased appetite and weight loss and in whom refeeding syndrome was documented after initiation of enteral nutrition. Clinical findings, blood work abnormalities and disease progression in this patient are described from the time of diagnosis through to recovery. A review of the current literature pertinent to this clinical syndrome is included.

[Drug treatment in surgical patients with electrolyte imbalances]

OBJECTIVE

To qualitatively and quantitatively determine electrolyte imbalances (potassium, phosphorus, magnesium and calcium) in patients admitted for general and gastrointestinal surgery, the degree of these imbalances in percentage detected by medical staff, and the acceptance of the recommendations made by the Hospital Pharmacy Department.

METHOD

Seven-month prospective study. Any alteration detected was recorded on a data collection form (personal data, hospital ward, type of alteration, detection by medical staff, type of pharmaceutical intervention, form of notification, acceptance of the intervention, date of imbalance correction, patient receiving parenteral nutrition).

RESULTS

100 imbalances were detected in 66 patients (231 analytical tests revised). A total of 78 interventions were carried out. Most changes were due to hypokalaemia and hypomagnesaemia, hypophosphataemia being the most frequent abnormality in patients receiving parenteral nutrition.The acceptance of pharmaceutical intervention was higher if the information was oral (100% vs. 35% written). Twice the number of analytical tests were performed after interventions (RR: 2.1, 95% CI: 1.11 to 3.94, P=.006). When pharmaceutical intervention was accepted there was a greater number of imbalance resolutions in comparison with those cases which did not accept (RR: 1.5, 95% CI: 1.01 to 2.24, P=.04).

CONCLUSIONS

This study shows that electrolyte imbalances are common in surgical patients and the level of detection and monitoring by medical staff is low. Therefore, the pharmacist could help in improving this aspect.

Different variations of tissue B-group vitamin concentrations in short- and long-term starved rats

Prolonged starvation changes energy metabolism; therefore, the metabolic response to starvation is divided into three phases according to changes in glucose, lipid and protein utilisation. B-group vitamins are involved in energy metabolism via metabolism of carbohydrates, fatty acids and amino acids. To determine how changes in energy metabolism alter B-group vitamin concentrations during starvation, we measured the concentration of eight kinds of B-group vitamins daily in rat blood, urine and in nine tissues including cerebrum, heart, lung, stomach, kidney, liver, spleen, testis and skeletal muscle during 8 d of starvation. Vitamin B1, vitamin B6, pantothenic acid, folate and biotin concentrations in the blood reduced after 6 or 8 d of starvation, and other vitamins did not change. Urinary excretion was decreased during starvation for all B-group vitamins except pantothenic acid and biotin. Less variation in B-group vitamin concentrations was found in the cerebrum and spleen. Concentrations of vitamin B1, vitamin B6, nicotinamide and pantothenic acid increased in the liver. The skeletal muscle and stomach showed reduced concentrations of five vitamins including vitamin B1, vitamin B2, vitamin B6, pantothenic acid and folate. Concentrations of two or three vitamins decreased in the kidney, testis and heart, and these changes showed different patterns in each tissue and for each vitamin. The concentration of pantothenic acid rapidly decreased in the heart, stomach, kidney and testis, whereas concentrations of nicotinamide were stable in all tissues except the liver. Different variations in B-group vitamin concentrations in the tissues of starved rats were found. The present findings will lead to a suitable supplementation of vitamins for the prevention of the re-feeding syndrome.

Cachexia, malnutrition, the refeeding syndrome, and lessons from Goldilocks

Cachexia has plagued clinicians for centuries. Although all cachexia is related to malnutrition, cachexia associated with malignant diseases differs from starvation cachexia in that it is more recalcitrant to nutritional therapy. All cachexia responds to judicious nutritional support; however, cancer cachexia worsens autonomously as the disease advances and cannot be arrested or reversed by any known form of nutrition, hormonal, or pharmacologic therapy. Cachexia must be treated cautiously to avoid overfeeding syndrome, which may result in serious or dangerous complications or death.

Refeeding syndrome: a literature review

Refeeding syndrome (RFS) describes the biochemical changes, clinical manifestations, and complications that can occur as a consequence of feeding a malnourished catabolic individual. RFS has been recognised in the literature for over fifty years and can result in serious harm and death. Crude estimates of incidence, morbidity, and mortality are available for specific populations. RFS can occur in any individual but more commonly occurs in at-risk populations. Increased awareness amongst healthcare professionals is likely to reduce morbidity and mortality. This review examines the physiology of RFS and describes the clinical manifestations. A management strategy is described. The importance of a multidisciplinary approach is emphasized.

Practical approach to paediatric enteral nutrition: a comment by the ESPGHAN committee on nutrition

Enteral nutrition support (ENS) involves both the delivery of nutrients via feeding tubes and the provision of specialised oral nutritional supplements. ENS is indicated in a patient with at least a partially functioning digestive tract when oral intake is inadequate or intake of normal food is inappropriate to meet the patients' needs. The aim of this comment by the Committee on Nutrition of the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition is to provide a clinical practice guide to ENS, based on the available evidence and the clinical expertise of the authors. Statements and recommendations are presented, and future research needs highlighted, with a particular emphasis placed on a practical approach to ENS.Among the wide array of enteral formulations, standard polymeric feeds based on cow's-milk protein with fibre and age adapted for energy and nutrient content are suitable for most paediatric patients. Whenever possible, intragastric is preferred to postpyloric delivery of nutrients, and intermittent feeding is preferred to continuous feeding because it is more physiological. An anticipated duration of enteral nutrition (EN) exceeding 4 to 6 weeks is an indication for gastrostomy or enterostomy. Among the various gastrostomy techniques available, percutaneous endoscopic gastrostomy is currently the first option. In general, both patients and caregivers express satisfaction with this procedure, although it is associated with a number of well-recognised complications. We strongly recommend the development and application of procedural protocols that include scrupulous attention to hygiene, as well as regular monitoring by a multidisciplinary nutrition support team to minimise the risk of EN-associated complications.

A comparative study of myocardial function and morphology during fasting/refeeding and food restriction in rats

BACKGROUND

This study compared the influence of fasting/refeeding cycles and food restriction on rat myocardial performance and morphology.

METHODS

Sixty-day-old male Wistar rats were submitted to food ad libitum (C), 50% food restriction (R50), and fasting/refeeding cycles (RF) for 12 weeks. Myocardial function was evaluated under baseline conditions and after progressive increase in calcium and isoproterenol. Myocardium ultrastructure was examined in the papillary muscle.

RESULTS

Fasting/refeeding cycles maintained rat body weight and left ventricle weight between control and food-restricted rats. Under baseline conditions, the time to peak tension (TPT) was more prolonged in R50 than in RF and C rats. Furthermore, the maximum tension decline rate (-dT/dt) increased less in R50 than in RF with calcium elevation. While the R50 group showed focal changes in many muscle fibers, such as the disorganization or loss of myofilaments, polymorphic mitochondria with disrupted cristae, and irregular appearance or infolding of the plasma membrane, the RF rats displayed few alterations such as loss or disorganization of myofibrils.

CONCLUSION

Food restriction promotes myocardial dysfunction, not observed in RF rats, and higher morphological damage than with fasting/refeeding. The increase in TPT may be attributed possibly to the disorganization and loss of myofibrils; however, the mechanisms responsible for the alteration in -dT/dt in R50 needs to be further clarified.

Refeeding syndrome

Refeeding syndrome (RFS) is the result of aggressive enteral or parenteral feeding in a malnourished patient, with hypophosphatemia being the hallmark of this phenomenon. Other metabolic abnormalities, such as hypokalemia and hypomagnesemia, may also occur, along with sodium and fluid retention. The metabolic changes that occur in RFS can be severe enough to cause cardiorespiratory failure and death. This article reviews the pathophysiology, the clinical manifestations, and the management of RFS. The key to prevention is identifying patients at risk and being aware of the potential complications involved in rapidly reintroducing feeds to a malnourished patient.

ESPEN Guidelines on Parenteral Nutrition: pancreas

Assessment of the severity of acute pancreatitis (AP), together with the patient's nutritional status is crucial in the decision making process that determines the need for artificial nutrition. Both should be done on admission and at frequent intervals thereafter. The indication for nutritional support in AP is actual or anticipated inadequate oral intake for 5-7 days. This period may be shorter in those with pre-existing malnutrition. Substrate metabolism in severe AP is similar to that in severe sepsis or trauma. Parenteral amino acids, glucose and lipid infusion do not affect pancreatic secretion and function. If lipids are administered, serum triglycerides must be monitored regularly. The use of intravenous lipids as part of parenteral nutrition (PN) is safe and feasible when hypertriglyceridemia is avoided. PN is indicated only in those patients who are unable to tolerate targeted requirements by the enteral route. As rates of EN tolerance increase then volumes of PN should be decreased. When PN is administered, particular attention should be given to avoid overfeeding. When PN is indicated, a parenteral glutamine supplementation should be considered. In chronic pancreatitis PN may, on rare occasions, be indicated in patients with gastric outlet obstruction secondary to duodenal stenosis or those with complex fistulation, and in occasional malnourished patients prior to surgery.

Recognizing and preventing refeeding syndrome

Refeeding syndrome is an uncommon but potentially fatal phenomenon that can occur in patients receiving parenteral, enteral, or oral feedings after a period of sustained malnutrition or starvation. This syndrome is characterized by hypophosphatemia, hypokalemia, and hypomagnesemia. The purpose of this article was to bring an acute awareness of refeeding syndrome to the critical care nurse. The recognition, pathogenesis, clinical manifestations, potential life threatening complications, and treatment are presented.

Coma

Coma is a state of unarousable unconsciousness due to dysfunction of the brain's ascending reticular activating system (ARAS), which is responsible for arousal and the maintenance of wakefulness. Anatomically and physiologically the ARAS has a redundancy of pathways and neurotransmitters; this may explain why coma is usually transient (seldom lasting more than 3 weeks). Emergence from coma is succeeded by outcomes ranging from the vegetative state to complete recovery, depending on the severity of damage to the cerebral cortex, the thalamus, and their integrated function. The clinical and laboratory assessments of the comatose patient are reviewed here, along with an analysis of how various conditions (structural brain lesions, metabolic and toxic disorders, trauma, infections, seizures, hypothermia, and hyperthermia) produce coma. Management issues include the determination of the cause and reversibility (prognosis) of neurological impairment, support of the patient, definitive treatment when possible, and the ethical considerations for those situations where marked disability is predicted with certainty.

Acute hypophosphataemia and hypokalaemia in a patient starting antiretroviral therapy in Zambia-a new context for refeeding syndrome?

High mortality rates have been reported in the first 90 days of antiretroviral therapy in Zambia and other low-income countries. We report a case of acute hypophosphataemia and hypokalaemia in the first week of antiretroviral therapy in a patient with extreme AIDS wasting. Given its occurrence in an extremely wasted patient, it may be physiologically similar to refeeding syndrome but other causes could be relevant as well. Acute hypophosphataemia may contribute to early antiretroviral therapy associated mortality in low-income countries.

Refeeding syndrome, an undiagnosed and forgotten potentially fatal condition

Refeeding syndrome (RFS) has been well described but is also a frequently forgotten and undiagnosed complication in clinical practice, which, if untreated, may lead to death. Patients who are more prone to developing RFS are those with at least one of the following conditions: BMI <16 kg/m(2), a recent unintentional weight loss >15%, very little nutritional intake for >10 days, and/or low plasma concentrations of potassium, phosphate or magnesium before feeding; and those with at least two of the following conditions: BMI <18.5 kg/m(2), a recent weight loss >10%, very little nutritional intake for >5 day, and/or a history of alcohol abuse or drug use, including insulin, chemotherapy or diuretics. We report here a patient who, after undergoing intestinal resection (short gut syndrome), presented diarrhoea, weight loss and protein-energy malnutrition. After nutritional assessment, the nutritional support team decided to feed the patient by the parenteral route. After 16 h of parenteral nutrition, the patient developed supraventricular tachycardia, hypomagnesaemia and hypocalcaemia, and RFS was diagnosed and managed. After intestinal adaptation, the patient is currently able to maintain his nutritional status with nutrition therapy by the oral route.

Challenges of nutrition intervention for malnourished dialysis patients

Malnutrition, or protein energy wasting (PEW), is prevalent in patients with chronic kidney disease stage 5 dialysis (CKD-5). One criterion of PEW strongly associated with morbidity and mortality in CKD-5 dialysis patients is the serum albumin level. Serum albumin levels have not improved over the past 10 years. Typical intervention strategies need to be reevaluated. Intradialytic parenteral nutrition (IDPN) is a form of parenteral nutrition delivered during dialysis that is a convenient and assured route of nutrition alimentation for high-nutrition-risk PEW patients who cannot improve nutrition status by oral and enteral routes. Recent qualification criteria for IDPN changes in Medicare part D have made this therapy an available option for many more of these high-nutrition-risk PEW patients. Nutrition support knowledge in clinicians is essential to administer IDPN effectively and to optimize clinical response. An improved understanding of the milieu of uremia and PEW of CKD-5, as well as the study of nutrition interventions inclusive of IDPN, will allow for effective strategies toward improved outcomes in the future.

How to recognize and respond to refeeding syndrome

If your patient is malnourished, you need to assess her carefully before she restarts nutrition by any route to avoid potentially lethal consequences.