How are you measuring your blood sugars?
I ask because I notice my CGM reports a false spike during my hot showers.
However, this is true spike on the graph - my levels appear to go up and then fall again without any insulin. It is not what I have seen described as a spike but is only one half - it is not a pla5eau where levels rise and stay there.
In short, my sensors report a spike but it does not happen, it is the sensor reacting to the heat rather than my body so there has been no need to make any changes.