Evaluation of levobupivacaine passage to breast milk following epidural anesthesia for cesarean delivery

Abstract

Both levobupivacaine and bupivacaine pass into breast milk following epidural administration. The concentration of both drugs was approximately three times lower in breast milk than in maternal plasma.

Should maternal anesthesia delay breastfeeding? A systematic review of the literature

“… 7 Several factors affect the excretion of medications into milk: maternal plasma concentration, protein binding, drug ionization, lipid and water solubility, drug molecular weight, and presence of active metabolites. 7 , 8 , 9 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 The susceptibility of the neonate to the drug depends on the maternal dose and duration of therapy, frequency of feeding, volume of milk consumed, bioavailability, the half-life of the drug in the infant, and maturity of the baby. Accordingly, premature babies are more susceptible to the adverse effects caused by medications.…”

Determination of milk/plasma ratio and milk and plasma pharmacokinetics of amoxicillin after intramuscular administration in lactating cows

“…The passage of amoxicillin into milk was found to be good compared with other penicillins because the M/P ratios of penicillins such as benzylpenicillin, ampicillin, and cloxacillin were between 0.13 and 0.30 (Adams, ). The best calculation of M/P ratio was based on the AUC for milk and plasma (Bolat et al., ; Fleishaker, ; Korth‐Bradley et al., ; Larsen, Ito, & Koren, ). However, the M/P ratio of drugs could be calculated on the basis of milk and plasma concentration at sampling times.…”

Exploring the transversus abdominis plane block in cesarean sections and the subsequent toxicity risk to neonates via breast milk

“…report that after epidural administration, both levobupivacaine and bupivacaine pass from the serum into breast milk similarly, with levobupivacaine found in a milk-to-plasma ratio of 0.34 ± 0.13 and bupivacaine with a milk-to-plasma ratio of 0.37 ± 0.14. [11] Another similar study reports that the milk-to-serum ratio is 0.34 ± 0.24 based on areas under the curve calculation for bupivacaine following epidural anesthesia. [12]…”

“…With a typical TAP block (as noted above, 20 mL of 0.25% bupivacaine bilaterally in a TAP block postoperation) in a relatively small woman (55 kg; this would encompass the vast majority of mothers), the resulting plasma concentration would equilibrate at a concentration of 2.02 μg/mL. [9] Assuming even low-birth-weight infant (1500 g), a breast milk to plasma concentration ratio of 0.37 (as noted above),[11] and a relatively small volume of distribution (2.56 L/kg),[141516] the neonate's plasma concentration after consumption of 60 mL of milk immediately after delivery would only reach 0.012 μg/mL. With two subsequent feedings, each 2 h apart, the concentration would reach a maximum of 0.018 μg/mL and then decline with subsequent feedings because of the decline in the mother's plasma concentration [Figure 1].…”