Each working day at least 40,000 Americans undergoing surgery require general anesthesia: an anesthesiologist renders them oblivious. Fifty years ago when the author Dr. Zeitlin began giving anesthesia in the United Kingdom one patient in 1500 died as a direct consequence of the anesthetic. That number was sadly true all over the world. In 2011 mortality and morbidity from anesthesia is too rare to count accurately. Nevertheless the increasing average age of patients coming to surgery and the inventiveness of surgeons require the same or greater vigilance and sophistication that has led to...