Effect-site Target-Controlled Infusion of Propofol and Alfentanil for Laryngeal Mask Airway (LMA) Insertion in Ambulatory Breast Surgery without Neuromuscular Blockade. |
Jeong Ki Lee, Moo Song Lee, Sung Lyang Chung, Gyu Jeong Noh |
1Departments of Anesthesiology and Pain Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea. nohgh@amc.seoul.kr 2Departments of Preventive Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea. |
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Abstract |
BACKGROUND We performed this study to evaluate the appropriate effect-site concentrations of propofol and alfentanil for LMA insertion in ambulatory breast surgery without neuromuscular blockade. METHODS Seventy-three ASA physical status 1 patients were enrolled. The administration of propofol and alfentanil was titrated versus bispectral index (BIS < 60), systolic blood pressure (SBP > or = 80 mmHg) and heart rate (HR > or = 50/min), respectively. The condition of LMA insertion was assessed as grade 1 (excellent), 2 (acceptable), and 3 (poor) according to gag, cough, movement, and laryngospasm.
We recorded SBP, HR and BIS before and after LMA insertion, the effect-site concentrations of propofol and alfentanil at the time of LMA insertion, and the LMA removal time at recovery. RESULTS The condition of LMA insertion at first attempt was grade 1 in 71.6% of patients, grade 2 in 20.3%, and grade 3 in 8.1%. After the first attempt at LMA insertion, movement occurred in 25.7% and the BIS increased above 60 in 31.5%.
The range of the effect-site concentrations of propofol and alfentanil at the first attempt were 2.0 6.0 (3.7 +/- 0.7)microgram/ml and 30.0 150.0 (71.6 +/- 24.4) ng/ml, which reflected a large inter-individual variability. The incidences of hypertension, tachycardia, hypotension, and bradycardia were 6.8%, 1.4%, 11.0% and 5.5%, respectively.
The mean LMA removal time was 4.7 min. CONCLUSIONS LMA was inserted successfully in 91.7% at first attempt and removed promptly at recovery. Movement and increase of BIS above 60 occurred frequently after the first attempt of LMA insertion with the effect-site target-controlled infusion of propofol and alfentanil without neuromuscular blockade. |
Key Words:
alfentanil; effect-site; laryngeal mask airway; neuromuscular blockade; propofol |
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