Table 1: Clinical manifestations of electrolyte abnormalities associated with refeeding syndrome [1, 59].

Clinical Manifestation

Phosphate ( )Hypophosphataemia (normal range 0.8–1.45 mmol/l) presents as
Cardiovascular: heart failure, arrhythmia, hypotension, cardiomyopathy shock, death
Renal: acute tubular necrosis, metabolic acidosis
Skeleton: rhabdomyolysis, weakness, myalgia, diaphragm weakness
Neurology: delirium, coma, seizures, tetany
Endocrine: hyperglycemia, insulin resistance, osteomalacia
Haematology: haemolysis, thrombocytopenia, leukocyte dysfunction

Potassium ( )Hypokalemia (normal range 3.5–5.1 mmol/l) presents as
Cardiovascular: hypotension, ventricular arrhythmias, cardiac arrest, bradycardia or tachycardia
Respiratory: hypoventilation, respiratory distress, respiratory failure
Skeleton: weakness, fatigue, muscle twitching
Gastrointestinal: diarrhoea, nausea, vomiting, anorexia, paralytic ileus, constipation
Metabolic: metabolic alkalosis

Magnesium ( )Hypomagnesaemia (normal range 0.77–1.33 mmol/l) presents as
Cardiovascular: paroxysmal atrial or ventricular arrhythmias, repolarisation alternans
Respiratory: hypoventilation, respiratory distress, respiratory failure
Neuromuscular: weakness, fatigue, muscle cramps (Trousseau and Chvostek) weakness, ataxia, vertigo, paresthesia, hallucinations, depression, convulsions
Gastrointestinal: abdominal pain, diarrhoea, vomiting, loss of appetite, and constipation
Other: anaemia, hypocalcemia
NB: many cases of hypomagnesaemia do not manifest clinically till very late

Sodium ( )Hyponatremia (normal range 136–145 mmol/l) ensues during RFS due to hyperglycaemia and presents as:
Cardiovascular: heart failure and arrhythmia
Respiratory: respiratory failure, pulmonary oedema.
Renal: renal failure
Skeleton: muscle cramps, fatigue, fluid retention and swelling (oedema)

VitaminsDeficiency of thiamine (especially in alcoholism) presents as
Neurology: Wernicke-Korsakoff syndrome, Karsakoff’s psychosis,
Cardiovascular: congestive heart failure and lactic acidosis, beriberi, disease
Skeleton: muscle weakness