[1] Harvard Med Sch, Brigham & Womens Hosp, Dept Anesthesiol Perioperat & Pain Med, Boston, MA USA
[2] Univ Calif San Diego, Dept Anesthesiol, Div Reg Anesthesia, San Diego, CA 92103 USA
[3] Univ Calif San Diego, Dept Anesthesiol, Div Perioperat Informat, San Diego, CA 92103 USA
[4] Univ Calif San Diego, Dept Biomed Informat, San Diego, CA 92103 USA
[5] Univ Calif San Diego, Dept Anesthesiol, Dept Biomed Informat, 200 West Arbor Dr Suite 770, San Diego, CA 92103 USA