The effects of preoperative anxiety on intravenous sedation.

Anxiety is known to cause feelings of uneasiness, tension, and nervousness, and previous studies have noted that anxiety and its effects may have an effect on out-patient sedation for patients undergoing surgical procedures. In this study, we assess the effects of anxiety on 25 outpatients undergoing intravenous sedation for third molar extraction. Before the procedure, subjects completed the State-Trait Anxiety Inventory, and intraoperative patient movement was assessed using a subjective scale. We found that patients with a high level of preoperative anxiety had a greater degree of average intraoperative movement (P = .037) and also required a greater amount of propofol to maintain a clinically acceptable level of sedation (P = .0273) when compared with patients with less preoperative anxiety. Increased state anxiety and trait anxiety serve as predictors for an increased total dose requirement of propofol to maintain an acceptable level of sedation (r2 = 0.285, P = .0060, and r2 = 0.233, P = .0146, respectively). An increased level of trait anxiety was also a predictor of an increased degree of average intraoperative movement (r2 = 0.342, P = .0022). Patients who exhibit a high level of preoperative anxiety require a greater total dose of propofol to achieve and maintain a clinically acceptable level of sedation and are more prone to unwanted movement while under sedation.