There are few studies comparing different concentrations of intravenous dextrose. In a randomised controlled trial (RCT) of pre-hospital treatment of adults unable to take oral carbohydrate, two concentrations of IV dextrose (10% and 50%) given in 5 g aliquots were compared.
There was no significant difference in time to return to Glasgow Coma Score (GCS) [11] but the group receiving 50% dextrose received a larger total dose and had higher post treatment blood glucose levels [7].
Two studies comparing IV dextrose with glucagon [12,13] by intramuscular and intravenous injection are often quoted in recommendations for the treatment of hypoglycaemia. However the dose of dextrose (50 ml of 50%) was higher than is commonly used now. The return to normal consciousness was slower for glucagon (IM more so than IV) than dextrose.
Glucagon tended to produce a steady rise in plasma glucose from low to the normal range, whereas IV dextrose produced high levels at 5 min which settled to normal by 30 min.
Learning Bite
In severe or prolonged hypoglycaemia cerebral oedema can develop. Dexamethasone, mannitol or controlled ventilation may be required after CT scanning.