Total intravenous anesthesia with propofol is associated with a lower rate of postoperative delirium in comparison with sevoflurane anesthesia in elderly patients.

STUDY OBJECTIVE: Postoperative delirium (POD) is a common complication of anesthesia. The incidence of POD in elderly patients ranges from 37% to 53%, and POD increases the morbidity and mortality of elderly patients. However, the effects of anesthetics on POD are not well known. The present study aimed to compare the incidence of POD resulting from propofol and sevoflurane anesthesia. DESIGN: Double-blind prospective study. SETTING: Operating room and postoperative recovery area. PATIENTS: Thirty patients in the sevoflurane anesthesia group and 29 in the propofol anesthesia group. MEASUREMENTS: Statistical analyses were performed using Microsoft Excel 2010 for Windows 7 (Microsoft Corporation, Redmond, Wash). Statistical analysis was performed using Fisher exact test and Student t test. MAIN RESULTS: The incidence of POD in the propofol anesthesia (6.9%) was significantly less than that observed in the sevoflurane anesthesia (26.7%; 038). CONCLUSION: In comparison with sevoflurane anesthesia, propofol anesthesia is associated with a lower incidence of POD in elderly patients.

Effects of amitriptyline, a tricyclic antidepressant, on smooth muscle reactivity in isolated rat trachea.

PURPOSE: This study was designed to investigate the action of amitriptyline, a tricyclic antidepressant, on airway smooth muscle reactivity and its underlying mechanisms. METHODS: In isolated rat trachea, isometric force was recorded to examine the effects of amitriptyline on the contractile response to acetylcholine (ACh), electrical field stimulation (EFS), calyculin A (a myosin light chain phosphatase inhibitor), and sphingosylphosphorylcholine (SPC; a Rhokinase activator). In addition, inositol monophosphate (IP1) accumulation was measured to examine its effects on inositol 1, 4, 5-trisphosphate (IP(3)) production during stimulation with ACh. RESULTS: Amitriptyline inhibited the contractile responses to ACh, EFS, calyculin A, and SPC, with the concentrations of amitriptyline (mean +/- SD) required to exert 50% inhibition (IC(50)) being 4.3 +/- 1.3 microM, 3.2 +/- 1.6 microM, 256.4 +/- 106.4 microM, and 98.2 +/- 21.8 microM, respectively. In addition, amitriptyline (10 microM) eliminated the ACh (10 microM)-induced IP(1) accumulation. CONCLUSION: The results suggest that amitriptyline does not influence tracheal smooth muscle reactivity at clinical concentrations (<1 microM), but attenuates the reactivity at supraclinical concentrations (> or =1 microM). The attenuated response to ACh brought about by amitriptyline is presumably due, at least in part, to the inhibition of phosphatidylinositol (PI) metabolism. The ability of amitriptyline to inhibit the calyculin Ainduced contraction suggests that amitriptyline also inhibits the Ca(2+)-calmodulin-myosin light chain pathway independently of the inhibition of PI metabolism. Finally, the difference between the IC(50) values for SPC-induced contraction and those for calyculin A-induced contraction suggests that amitriptyline may also inhibit the Rho-kinase pathway.