• A Casati, G Fanelli, E Casaletti, V Cedrati, F Veglia, and G Torri.
• Department of Anesthesiology, University of Milan, Italy. casati.andrea@hsr.it
• Anesth. Analg. 1999 Apr 1; 88 (4): 917-20.

UnlabelledTo determine the target plasma concentration of propofol required to place either a laryngeal mask airway (LMA) or a cuffed oropharyngeal airway (COPA), we started a continuous target-controlled infusion of propofol in 60 ASA physical status I or II unpremedicated patients scheduled for minor orthopedic surgery with peripheral nerve block. The target plasma concentration of propofol was initially set at 2 microg/mL. When the effect-site calculated concentration of propofol was equal to the plasma concentration according to the computer simulation, the target plasma concentration was increased by 0.5-microg/mL steps until successful placement of either the LMA (n = 30) or the COPA (n = 30). The mean target plasma concentration of propofol required to place a LMA was 4.3 +/- 0.8 microg/mL compared with 3.2 +/- 0.6 microg/mL to place a COPA (P < 0.001). To successfully place the airways in 95% of patients, the target plasma concentration of propofol had to be increased up to 4 microg/mL for the COPA and 6 microg/mL for the LMA. We conclude that placing a LMA in healthy, unpremedicated patients requires target plasma concentrations of propofol higher than those required for placing a COPA.ImplicationsWe evaluated the use of target-controlled infusion of propofol to place extratracheal airways in this prospective, randomized study and demonstrated that the target plasma concentration of propofol required to successfully place a laryngeal mask in >95% of healthy, unpremedicated patients is 6 microg/mL, compared with 4 microg/mL to place a cuffed oropharyngeal airway.

17 keywords...

hide…