I had 54 yrs old male ASA I, post cholecystectomy with H/O fever, R abdominal pain since 4 days,admitted for ERCP under GA, pt induced with fantasy100mcg, proposal 60mg, attach rim 40 mg, Intubation and anesthesia maintained with O2, NO, ISO,after 10 min during procedure pt had desaturated, hand ventilated with 100%O2, ET tube position confirmed, pt picked up saturation so procedure restarted, again pt dropped his EtCO2 , saturation n went in PEA,IMMEDIATELY cardiac resuscitation started but even after immediate measures could not able to revive the pt. If anybody having any experience in such cases, please share and any suggestions are welcomed.