Fig. 1.  Flow diagram: 51 patients were assessed for eligibility and 11 patients were excluded during preoperative reevaluation because latent arterial hypertension, untreated diabetes mellitus, and drug abuse (hypnotics) were suspected. Two patients initially scheduled for abdominal hysterectomy finally received laparoscopic surgery. Forty patients were allocated into one of two equally sized groups (xenon [verum ], air [placebo ]). One patient of the xenon group was lost to postoperative follow-up because of secondary bleeding, and one patient of the placebo group was postoperatively excluded because she accidentally received lorazepam.60