The role of laparoscopic appendectomy (LA) for perforated appendicitis is under investigation. According to the results of a previous retrospective study conducted in Far-Eastern Memorial Hospital comparing the clinical outcomes between perforated appendicitis patients treated by laparoscopic and open approach showed favored clinical outcomes for LA. Same as a few studies indicated that laparoscopic appendectomy is a safe and effective procedure for treating patients with perforated appendicitis in terms of hospital stay and wound complications. One the other hand, some authors still concern about the adverse effects of laparoscopy for ruptured appendicitis patients in terms of longer operation time and increased rates of postoperative abscess formation. We hypothesize that prolonged CO2 pneumoperitoneum will produce transient mesenteric ischemic and reperfusion injury when CO2 disinflation, and the free radicals and oxidative proteins provoked by reperfusion injury are responsible for the adverse reaction of LA. The objective of this prospective non-randomized controlled study is to examine the safety and efficacy of laparoscopic appendectomy and compare its outcome with that of the conventional approach for perforated appendicitis patients, with special emphasis on postoperative complication and oxidative stress resulted from pneumoperitoneum..