Six percent hydroxyethyl starch 130/0.4 impacts differently on blood glucose than 4% gelatine in a swine model of mixed acidaemia.

Background: Tris-hydroxymethyl aminomethane can be used as a buffer in case of restricted ventilation, but hypoglycaemia is one adverse effect. The influence of a starch-based colloid [6% hydroxyethyl starch 130 kDa/0.4 (HES130)] vs. a gelatine-based colloid (4% polysuccinated gelatine) on blood glucose was investigated in a swine model of mixed acidaemia.

Methods: Continuous colloid infusion was done in anaesthetized pigs with exogenously induced mixed acidaemia, which was maintained for 3 h. Pigs (approximately 40 kg, n = 6 in each group) were randomized to HES130 or 4% gelatine infusion (4 ml kg h(-1)). Infusion of an acid solution and low tidal volume ventilation induced mixed acidaemia. Treatment of mixed acidaemia with tris-hydroxymethyl aminomethane buffer, which is known to induce hypoglycaemia, prolonged anaesthesia, and volume support challenged the control of blood glucose. Hypoglycaemia was treated by individually dosed infusion of 5% glucose in sterile water.

Results: Bolus infusion of HES130 led to a moderate peak in blood glucose in four pigs. Four pigs in the 4% gelatine group and three in the HES130 group needed glucose infusion to prevent a drop in blood glucose levels below the set threshold (4 mmol l(-1)). The total amount of the glucose infusion was significantly lower in the HES130 group compared with the 4% gelatine group (100 vs. 295 ml per pig, median, P < 0.05). Generally, the HES130 pigs required glucose at later time points during anaesthesia. The first HES130 pig needed 5% glucose 2 h later than the first 4% gelatine pig to prevent a drop of blood glucose below 4 mmol l(-1).

Conclusion: Volume support impacted specifically on blood glucose in this porcine model. Thus, an additional control of blood glucose seems recommendable whenever a change in the volume support occurs.