title: Placental transfer of lidocaine hydrochloride after prolonged continuous maternal intravenous administration.
abstract: We treated a patient with arrhythmia during pregnancy with prolonged intravenous administration of lidocaine hydrochloride. This was a case of twin-to-twin transfusion syndrome and the arrhythmia was caused by ritodrine therapy. In total, 14.1 g lidocaine (50 mg.hr-1 for 282 hr) were used. Since there are no descriptions of human placental transfer of lidocaine after such a prolonged continuous intravenous administration, we measured lidocaine concentrations in maternal and fetal serum, and in the amniotic fluid (AF) at delivery. Fetal serum lidocaine concentrations (donor: 0.83 microgram.ml-1; recipient: 0.82 microgram.ml-1) were lower than in the maternal serum (1.6 micrograms.ml-1), while the AF lidocaine concentrations (donor: 1.05 micrograms.ml-1; recipient: 1.04 micrograms.ml-1) were higher than those of the fetal sera. The fetal/maternal concentration ratios of lidocaine were 0.52 for the donor and 0.51 for the recipient, which were similar to those described previously after administration of lidocaine in labour.
authors.affiliation: Department of Obstetrics and Gynecology, Yamagata University School of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Banzai
authors.forename: S
authors.initials: S
authors.lastname: Sato
authors.forename: N
authors.initials: N
authors.lastname: Tezuka
authors.forename: H
authors.initials: H
authors.lastname: Komiya
authors.forename: T
authors.initials: T
authors.lastname: Chimura
authors.forename: M
authors.initials: M
authors.lastname: Hiroi
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000737:chemistry; D001145:Arrhythmias, Cardiac / Q000097:blood / Q000139:chemically induced / Q000188:drug therapy; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D005330:Fetofetal Transfusion / Q000175:diagnosis; D006801:Humans; D007262:Infusions, Intravenous; D008012:Lidocaine / Q000008:administration & dosage / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*; D008431:Maternal-Fetal Exchange; D007752:Obstetric Labor, Premature / Q000517:prevention & control; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000097:blood / Q000139:chemically induced / Q000188:drug therapy; D011272:Pregnancy, Multiple; D012312:Ritodrine / Q000009:adverse effects; D014427:Twins
chemical_list: D008012:Lidocaine; D012312:Ritodrine