84children patients, ASA 1 or 2, at the age from 1.5 months to 15 years, elective surgeries were general anesthetized by using propofol or Sevoflurane + Propofol for induction and classic - Laryngeal Mask Airway for airway management; using muscular relaxants depends on the surgical requirements. Results: From 06/2009 to 04 / 2010, we studied 84 children patients, ASA 1 or 2, weight from 4.8 to 63 kgs (average weight 17.8 + 9 kgs), 79% male and 21% female.