Send which fields we want returned in the API response

Is there a way to send which fields we want returned through the tickets API? 

The situation we are finding ourselves in is we make an API to get ticket info and it returns all of the custom fields. This in and of itself isn't horrible (also isn' the best) but if we want to do anything with the response, such as looking up a specific field ID to get its value we need to iterate through all fields to get it. This can take time and in the world of automation time is never on your side. Our though is that if we can specify which id's we want returned this would be a non-issue. If thats not possible then is there a recommended search method, I should be looking into to be more efficient when iterating through the custom_fields array?