Preoperative anxiety and intraoperative anesthetic requirements

The purpose of this study was to determine whether larger doses of anesthet ics are required in the anxious patient to establish and maintain a clinica lly sufficient hypnotic component of the anesthetic state. Fifty-seven wome n undergoing bilateral laparoscopic tubal ligation with a propofol-based an esthetic regimen were enrolled in this cross-sectional study. Trait (baseli ne) and state (situational) anxiety were assessed in all patients immediate ly before surgery, and the propofol doses required for the induction and ma intenance of anesthesia were recorded. A bispectral index monitor was used to assure that the hypnotic component of the anesthetic state was the same in all patients. We found that patients with high trait anxiety required mo re propofol for both the induction (2.1 +/- 0.4 vs 1.8 +/- 0.3 mg/kg; P = 0 .01) and maintenance of anesthesia (170 +/- 70 vs 110 +/- 20 mu g.kg(-1).mi n(-1); P = 0.02), compared with patients with low trait anxiety. State anxi ety, however, was not found to affect the propofol doses required for the i nduction or maintenance of anesthesia. Multiple regression models confirmed that Trait anxiety is an independent predictor for intraoperative propofol requirements (P = 0.02). We conclude that increased baseline (i.e., trait) anxiety is associated with increased intraoperative anesthetic requirement s. Thus, we suggest that the initial dose of anesthetic administered by an anesthesiologist should be modified based on the anxiety level exhibited by the patient. Implications: The goal of this study was to assess the relati onship between preoperative anxiety and intraoperative anesthetic requireme nts. We found that high baseline anxiety predicts increased intraoperative anesthetic requirements. We suggest that anesthesiologists should modify th e initial induction dose based on the anxiety level exhibited by the patien t.