title: The pharmacokinetics of caudal ropivacaine 0.2% in children. A study of infants aged less than 1 year and toddlers aged 1-5 years undergoing inguinal hernia repair.
abstract: This study evaluates the pharmacokinetics of ropivacaine in children after caudal epidural injection. Twenty male children undergoing inguinal hernia repair were enrolled after ethics committee approval and informed parental consent, and were grouped according to age (10 'infants' aged less than 1 year and 10 'toddlers' aged 1-5 years). After induction of general anaesthesia, caudal epidural injection using ropivacaine 0.2% 1 ml.kg-1 was performed. Plasma concentrations of ropivacaine in the first 2 h after injection were determined by reversed-phase high-pressure liquid chromatography. Caudal blockade with ropivacaine 2 mg.ml-1 resulted in mean (SD) peak plasma concentrations of 0.73 [0.27] microg.ml-1 in infants and 0.49 [0.21] microg.ml-1 in toddlers (p < 0.01). Maximum plasma concentrations occurred after a median [range] period of 60 [15-90] min and 52.5 [30-120] min in infants and toddlers, respectively. Two infants (weighing 3.8 and 5.0 kg) showed the highest individual maximum plasma concentrations: 1.31 and 1.11 microg.ml-1. No clinical signs of local anaesthetic toxicity were observed. The results of the present investigation suggest that, from a pharmacokinetic point of view, caudal blockade using ropivacaine 0. 2% 1 ml.kg-1 can be regarded as a safe technique in children, i.e. in infants as well as in toddlers.
authors.affiliation: Department of Anaesthesiology and Critical Care Medicine, Hospital of the Christian-Albrechts-University, Schwanenweg 21, D-24105 Kiel, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Wulf
authors.forename: C
authors.initials: C
authors.lastname: Peters
authors.forename: H
authors.initials: H
authors.lastname: Behnke
mesh_terms: D000577:Amides / Q000097:blood / Q000493:pharmacokinetics*; D000763:Anesthesia, Caudal / Q000009:adverse effects*; D000779:Anesthetics, Local / Q000097:blood / Q000493:pharmacokinetics*; D002675:Child, Preschool; D006552:Hernia, Inguinal / Q000378:metabolism / Q000601:surgery; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011446:Prospective Studies; D000077212:Ropivacaine; D016896:Treatment Outcome
chemical_list: D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine