71 - 75 SBAs for the Final FRCA
Question 71
You are the ITU registrar on call, and are asked to review a young man with severe anorexia on the ward. Originally admitted for poor oral intake and urine output, he has been receiving NG feeding for three days.
He has become profoundly confused and agitated in the last few hours and the ward are asking for your help in managing him.
What is probably going on?
- Urinary tract infection
- Intracerebral haemorrhage
- Hypophosphataemia
- Hyponatraemia
- Hypokalaemia
Answer
- Hypophosphataemia
Classic refeeding syndrome.
Starved of electrolytes, the body (and brain in particular) recruits intracellular deposits of phosphate into the blood.
When a surge of NG feed enters the arena, the cells all rejoice by sending all of the phosphate back into the cells where it belongs, so that protein synthesis can start up again.
This causes a sudden drop in intravascular phosphate concentration, and all the hallmark symptoms of hypophosphataemia.
The main problems are:
- abdominal pain
- reflux
- arrhythmias
- heart failure
- confusion
- coma
To avoid this, ensure adequate phosphate supplementation prior to and during restarting feeding.
Refeeding syndrome is technically any electrolyte disturbance occuring within four days of restarting feed in a malnourished patient, but phosphate is usually the culprit.