Hello,
The insulin works '' better '' because your veins getting wider. I think you must do alittle more than trusting your pump and sensor. For instance if I eat 80 grammes of carbohydrate with tropical temperature i will ask my pump to suggest the recommended dose of insulin and only use half of what is recommends.
What also works is reducing your basal dose with a certain percentage. Usually i will reduce it with 50% when i am in a tropical country.
Or '' tell '' the pump to regulate it to higher value because with a lower value in Vietnam it will not take a lot of '' exercise '' to make it go down to much.
IF i am right your body will need extra water to be able to make the insulin work properly.
Greetings, Eduard