ABSTRACT
The objectives were to evaluate the time course for atenolol pharmacokinetics in lactating women postpartum and to quantify atenolol plasma concentrations in the women's 3- to 4-month-old nursing infants. Data were collected during 1 dosing interval from lactating women treated with atenolol for therapeutic reasons, at 2 to 4 weeks (n = 32), 3 to 4 months (n = 22), and 6 to 8 months (n = 17) postpartum. A single blood sample was collected from 15 nursing infants (3-4 months of age) of the mothers participating in the study. At 2 to 4 weeks, 3 to 4 months, and 6 to 8 months postpartum, atenolol infant doses, relative to the mother's weight-adjusted dose, were 14.6% ± 7.6%, 8.3% ± 5.2% and 5.9% ± 2.9%, respectively. Over this time, maternal atenolol pharmacokinetics did not change to a clinically significant extent. Atenolol concentrations were below assay quantification limits (<10 ng/mL) in the plasma of all 3- to 4-month-old nursing infants studied. These findings support the careful use of atenolol during breastfeeding, because in the vast majority of healthy, term infants, atenolol concentrations will be too low to be clinically relevant. Premature infants and those with kidney disease require further study. Infant exposure depends on maternal dose and decreases during the first 6 to 8 months postpartum.
Subject(s)
Antihypertensive Agents/pharmacokinetics , Atenolol/pharmacokinetics , Milk, Human/chemistry , Adult , Antihypertensive Agents/administration & dosage , Atenolol/administration & dosage , Dose-Response Relationship, Drug , Female , Follow-Up Studies , Humans , Infant , Lactation , Male , Postpartum Period , Pregnancy , Time FactorsABSTRACT
OBJECTIVE: Zinc protoporphyrin/heme ratio (ZnPP/H) has been well established as an indicator of functional iron deficiency in subjects 6 months of age to adult. The primary objective of this study was to establish normative values for ZnPP/H in NICU patients and secondarily to explore the utility of this test as an indicator of iron deficiency in neonates. Study design ZnPP/H and complete blood counts were obtained weekly on consecutive NICU patients. Gestational age, growth variables, iron supplementation, erythropoietin treatment, and blood transfusions were documented. Results are reported as mean +/- SD. A value of P <.05 was considered significant. RESULTS: ZnPP/H ratios (n = 639) were evaluated from 143 infants. During the first week of life, ZnPP/H was inversely correlated with gestational age (n = 78, P <.001, r = -0.72). Maternal diabetes, growth retardation, and exposure to chorioamnionitis were independent risk factors for high ZnPP/H. Both iron supplementation and blood transfusion decreased ZnPP/H (P <.001). Erythropoietin treatment was associated with an increase in reticulocyte count and ZnPP/H (P <.001). CONCLUSIONS: ZnPP/H is inversely correlated with gestational age, and the range in all newborn infants is higher than in adults. ZnPP/H is elevated in certain infant subpopulations, which suggests that they may require additional iron supplementation.
Subject(s)
Heme/analysis , Iron Deficiencies , Protoporphyrins/blood , Biomarkers/blood , Blood Cell Count , Erythrocyte Transfusion , Erythropoietin/therapeutic use , Ferrous Compounds/therapeutic use , Gestational Age , Humans , Infant, Newborn , Intensive Care Units, Neonatal , Recombinant Proteins , Reference Values , Risk FactorsABSTRACT
A 3-day-old infant unexpectedly developed cardiopulmonary arrest at home. A resuscitation process was initiated and the infant was transported to a nearby community hospital where a highly respected senior pediatrician assumed responsibility for the prolonged resuscitation. Following cessation of aggressive support measures, the infant resumed gasping/respiratory efforts. The pediatrician admitted to occluding the infant's nose and mouth just before death. Several of the important medical issues and ethical distinctions are discussed.
