Peroperative: Type of procedure, tube size/laryngeal mask, type of tongue blade, highest/lowest SpO2, highest/lowest ET CO2, highest/lowest pulse, length of surgery, total operating room time, operator, medication. Reason must be given if converting from laryngeal mask to tube; lack of visibility for operator, laryngeal mask not possible to place, unacceptable leakage before placing tongue blade, occlusion after placement of tongue blade.