From the Guidelines
Refeeding syndrome is a severe and potentially life-threatening condition that occurs in malnourished patients when feeding is begun too aggressively after a period of inadequate nutrition.
Characteristics of Refeeding Syndrome
- Electrolyte imbalance: hypophosphatemia, hypokalaemia, hypomagnesemia, and hypocalcaemia are common electrolyte disturbances [ 1 ]
- Fluid retention: peripheral oedema, congestive heart failure, and respiratory failure can occur due to fluid imbalance [ 1 ]
- Cardiac arrhythmia: and other severe organ dysfunctions, such as delirium and encephalopathy, can be clinical symptoms of refeeding syndrome [ 1 ]
- Glucose homeostasis: disturbed glucose homeostasis and hyperlactatemia suggesting vitamin B1 deficiency are also characteristic of refeeding syndrome [ 1 ]
Risk Factors
- Malnutrition: patients with chronic alcoholism, severe chronic undernutrition, anorexia nervosa, or depleted patients with acute illness are at high risk [ 1 ]
- Low BMI: patients with a BMI <16 kg/m2 or unintentional weight loss >15% in 3-6 months are at risk [ 1 ]
- Little or no intake: patients with little or no intake for >10 days or low potassium, phosphate, and magnesium before feeding are also at risk [ 1 ]
Prevention and Treatment
- Hypocaloric diet: an initial phase of a hypocaloric diet is indicated for patients with a high risk of refeeding syndrome [ 1 ]
- Gradual increase in calories: nutritional therapy should be started with low caloric input and increased step by step over five to ten days, according to the individual's risk of refeeding syndrome and clinical features [ 1 ]
- Electrolyte monitoring and substitution: potassium, phosphate, and magnesium should be monitored and substituted, if necessary, by the oral, enteral, or parenteral route [ 1 ]
From the Research
Characteristics of Refeeding Syndrome
The characteristics of refeeding syndrome include:
- Hypophosphatemia, which is the hallmark feature of the syndrome 2, 3, 4, 5, 6
- Hypokalemia, which is a common biochemical abnormality 2, 3, 4
- Hypomagnesemia, which is also a common biochemical abnormality 2, 3, 4
- Thiamine deficiency, which can occur due to increased demand during refeeding 2
- Disorders of sodium and fluid balance, which can lead to complications such as cardiac arrhythmia and respiratory insufficiency 2, 4
- Metabolic abnormalities, such as hyperglycemia, although this is not consistently reported in all cases 3, 6
Clinical Presentation
The clinical presentation of refeeding syndrome can vary, but it often includes:
- Severe electrolyte disturbances, particularly hypophosphatemia, hypokalemia, and hypomagnesemia 3, 4
- Metabolic abnormalities, such as hypocalcemia and hyponatremia, although these are not consistently reported in all cases 6
- Clinical signs and symptoms, such as cardiac arrhythmia, systolic heart failure, respiratory insufficiency, and hematologic derangements 4
Diagnosis and Definition
There is no universally accepted definition of refeeding syndrome, which can make diagnosis and management challenging 2, 3, 6. The presence of hypophosphatemia alone does not necessarily mean that refeeding syndrome is present, as there are many other causes for this condition 3. A systematic review of reported cases and case series found that hypophosphatemia was a consistent finding, but other biochemical and clinical abnormalities were not consistently identified 6.