Ticarcillin serum and tissue concentrations in gynecology and obstetrics

Ticarcillin tissue concentrations were determined in 77 patients following an infusion of 5 g over 30 min. The tissues studied in gynecology were endometrium, tube, ovary and myometrium. The relative tissue levels ranged from 17% to 30% of the corresponding serum concentrations when ticarcillin was administered once, and from 22% to 32% when the drug was infused repeatedly. In no case did these tissue levels exceed the serum concentrations. The mean relative tissue levels in early pregnancy (decidua, placenta, embryo) were 10% of the corresponding serum concentrations. Levels in late pregnancy were determined in the placenta, amniotic fluid and in serum from the umbilical cord artery and vein immediately after delivery. Maximal placenta concentrations of 30 mg/kg were determined; these declined exponentionally with half-lives of 2.8 and 1.3 h, respectively, following single and repeated dosings. Amniotic fluid levels increased from 10 mg/l immediately after the first infusion to 60 mg/l after the seventh infusion. Individual umbilical cord levels in the artery and vein were significantly different, indicating that the fetus has properties of a deep compartment. The total amount of ticarcillin excreted daily in the mother's milk was strictly correlated to its volume and ranged from 2-2.5 mg/l.