Refeeding Syndrome

Abstract

Background: Refeeding syndrome (RFS) can occur in malnourished patients when normal, enteral, or parenteral feeding is resumed. The syndrome often goes unrecognized and may, in the most severe cases, result in death. The diagnosis of RFS can be crucially facilitated by the use of clinical decision support systems (CDSS).

Methods: The literature in PubMed was searched for current treatment recommendations, randomized intervention studies, and publications on RFS and CDSS. We also took account of insights gained from the development and implementation of our own CDSS for the diagnosis of RFS.

Results: The identification of high-risk patients and the recognition of manifest RFS is clinically challenging due to the syndrome's unspecific symptoms and physicians' lack of awareness of the risk of this condition. The literature shows that compared to patients without RFS, malnourished patients with RFS have significantly greater 6-month mortality (odds ratio 1.54, 95% confidence interval: [1.04; 2.28]) and an elevated risk of admission to intensive care (odds ratio 2.71 [1.01; 7.27]). In a prospective testing program, use of our own CDSS led to correct diagnosis in two thirds of cases.

Conclusion: RFS is difficult to detect and represents a high risk to the patients affected. Appropriate CDSS can identify such patients and ensure proper professional care.

Figure 1

Pathophysiology of refeeding syndroms (RFS), modified from Nguyen et al (40). In catabolism, energy production takes place via glycogenolysis and gluconeogenesis. Liver glycogen is generally used up after 12–24 h. Thereafter, primarily ketones from fatty acid oxidation serve as substrates of gluconeogenesis. Intracellular reserves of phosphate, potassium, and magnesium are used to maintain electrolyte homeostasis and become depleted in the absence of food intake. Serum electrolyte concentrations within the reference range mask a growing intracellular deficit. Upon reintroduction of feeding, insulin is secreted, thereby stimulating sodium–potassium ATPase and enabling the intracellular influx of glucose and phosphate. Thus, carbohydrates are once again available as substrates for glycolysis. Carbohydrate metabolism requires magnesium and thiamine (vitamin B1) as essential cofactors. The half-life of physiological vitamin B1 storage is 7–10 days and is quickly exhausted in the case of low food intake. The onset of glycolysis triggers a rapidly increasing requirement for vitamin B1 and electrolytes. Acute deficiency causes RFS complications. *¹ Balanced diet, e.g., 50% calories from carbohydrates, 30% fats, 20% protein; ^*2 intracellularly used for pyruvate entry into the cycle kcal: kilocalories; CHO, carbohydrates.

Figure 2

Recommendations on refeeding in patients at risk of refeeding syndrome and treatment recommendations in manifest refeeding syndrome according to the consensus recommendations (2) of the American Society for Parenteral and Enteral Nutrition P, potassium; Mg, magnesium; PO4, phosphate

eFigure 1

Flow diagram showing the data analysis of retrospective data from January 2019 to June 2021 (left) and the prospective test phase (right) of the clinical decision support system (CDSS) using inclusion and exclusion criteria and the subsequent automated evaluation of decreases in the level of electrolytes (phosphate, potassium, magnesium) in refeeding syndrome. TP, true positive