[Adsorption of local anesthetic into disposable infusion balloon].
BACKGROUND
The aim of this study was to investigate the adsorption of local anesthetics lidocaine and ropivacaine, into disposable infusion balloons made from various kinds of plastics.


METHODS
The concentration of local anesthetic that flows out of a balloon was measured.


RESULTS
The concentration of both lidocaine and ropivacaine in clinical formula decreased only 4.5 percent regardless of infusion balloons. However, the concentration of lidocaine pH 7.4 decreased by 10 percent in the Syrinjector made from polypropylene and polyvinyl chloride, and that of 18-20 percent in other infusion balloons (Surefuser, Baxtor Infuser, DIB Catheter made from isoprene rubber and polyvinyl chloride, isoprene rubber and polyvinyl chloride, silicon and polyvinyl chloride, respectively).


CONCLUSIONS
The adsorption of local anesthetic into infusion balloons has little effect in clinical situation. Whereas, in case of lidocaine pH 7.4, the adsorption depends on the specific type of plastics.
Department of Anesthesiology, Osaka University Medical School, Suita 565 0871.
Kazuyoshi
K
Ueta
Takahiro
T
Suzuki
Ichiro
I
Uchida
Takashi
T
Mashimo
D000327:Adsorption; D000577:Amides / Q000494:pharmacology; D000779:Anesthetics, Local / Q000493:pharmacokinetics*; D002404:Catheterization / Q000295:instrumentation*; D004209:Disposable Equipment; D006801:Humans; D008012:Lidocaine / Q000493:pharmacokinetics; D010969:Plastics; D000077212:Ropivacaine
D000577:Amides; D000779:Anesthetics, Local; D010969:Plastics; D000077212:Ropivacaine; D008012:Lidocaine