Nevertheless, in the seven years since the ASA introduced its guidelines, the approach has made remarkably little headway in the nation's hospitals, clinics and surgery centers. In most settings, NPO after midnight remains more or less the medical law of the land.
"Do not eat or drink after midnight the day before your surgery," say the online pre-surgery instructions for the Cheshire Medical Center, a hospital in Keene, N.H. "If you eat or drink anything after midnight, your surgery will be cancelled."
Recent research provides stronger evidence. A 2002 study by [Jeanette Crenshaw] and Winslow found that among 151 elective surgery patients at Presbyterian Hospital of Dallas, the average fasting time for clear liquids was 12 hours, about six times longer than the ASA recommends. The average time for going without food was 14 hours.