TSH lab work ordered..consent 305.1?

I am having surgery and I am not supposed to have smoked for 6 months but I admit I have here and there and smoked the hookah..so I got a paper today saying I need to get some lab work done. It has TSH checked and underneath is says Consent: Tobacco Disorder 305.1 what does that mean? What exactly am I being tested for? Are they testing me for nicotine or what?