The most likely cause for increased blood sugar levels after surgery seems to be due partly to increased rest and more calorie intake.However there should not be any problem in controlling it.
Make sure to take note of your calorie intake and reduce it partly and if you find that sugar levels are still not controlled,then add another anti diabetic medicine to your current regime.
This can be a sulfonylurea
like long acting DIAMICRON
.However addition of any anti diabetic has to be done by your treating doctor and not by yourself.