If you know you want to do anesthesiology that's great and research in the field can always help. Keep in mind though that a lot of people don't know what field they want to go into when they are M1/M2's, thus research in general is probably still a plus (and would be beneficial when applying to any field of medicine).
In short, I don't think that your research project holds you to a specific specialty... it will help your application regardless. However, if you know you want anesthesia... it gives you a bit of a leg up on the process. I would say that even though good amount of people have research, it's definitely not always in the field of anesthesiology (mine wasn't... I didn't know I was going to do anesthesiology until my M3 year rotation).