I've been out of school for 9 months now and have done several hundred EGD cases (in school and after). I was curious as to the techniques that people find beneficial to prevent coughing, etc on the scope. I have been giving 500 mcg alfentanil to younger patients and 250 mcg to older, along with propofol and a bolus of lidocaine right before the start. It seems to work great on average sized people and people who don't smoke. However, my smokers and overweight patients seem to start coughing, and hence, the rapid desaturation that all of them tend to possess. Obviously, my doses are probably too small per kg of weight, but it led me to wonder if there are better techniques that people would like to share. Any advice?