30th July 2023

Refeeding Syndrome

Overview

Refeeding syndrome is a potentially fatal consequence of artificial nutritional replacement in malnourished patients, and refers to a collection of electrolyte disturbances due to the shifts in homeostasis that occur.

The characteristic electrolyte abnormalities are:

• Hypophosphataemia
• Hypokalaemia
• Hypomagnesaemia

It is also associated with deficiency of key micronutrients, such as thiamine.

Causes

Anyone who is malnourished can develop refeeding syndrome, but it is a particular risk factor for the elderly, people with eating disorders, cancer patients, alcoholics, and the chronically malnourished, with there being an association between the chronicity of the malnourishment and the risk of the disease.

Clinical features

These are generally the consequences of the associated electrolyte deficiencies.

They include muscle weakness, abdominal pain, constipation, and nausea/vomiting. More serious manifestations are of the CNS and cardiovascular system, such as ataxia, seizures, delirium, coma, and life-threatening cardiac arrhythmias. Torsades de pointes and subsequent ventricular fibrillation are a particular risk due to hypokalaemia.

Thiamine deficiency can cause Wernicke’s encephalopathy, and the irreversible Korsakoff’s syndrome, if untreated.

Management 

The risk of life-threatening arrhythmias means patients identified to have refeeding syndrome may require cardiac monitors. Any complications of refeeding syndrome should be appropriately managed.

Prevention is key – patients at risk of refeeding syndrome should be identified prior to nutritional replacement. Preventative measures include early thiamine supplementation, and a carefully monitored slow rate of artificial nutrition and fluid replacement, for which each hospital will have local guidelines. Regular electrolyte monitoring is required.

NICE recommends that refeeding is started at no more than 50% of energy requirements in “patients who have eaten little or nothing for more than 5 days” in order to reduce the risk of developing refeeding syndrome.