Levels Lidocaine in the Newborn after an Episiotomy given to the Mother

Lidocaine is administered to the mother as local anesthetic before performing a
surgically planned incision to the perineum (episiotomy) during delivery.
In Amphia Hospital two cases have been presented with a possibility of
intoxication with lidocaine, following medical signs. Levels could not exclude
an incorrect gift of lidocaine via the maternal perineum directly in the head
skin of the child, or a concentration caused by transmission via the maternal
blood when it was administered locally to the mother.
Transmission of lidocaine to the child via the umbilical cord is possible. To
define exactly when an intoxication will occur in newborns, it is necessary to
determine the lidocaine concentrations in a child after delivery when lidocaine
is locally administrated to the mother. It is also interesting to look at the
interval between administration of lidocaine and the time of delivery in
relation to the degree of transmission of lidocaine to the child. In the
current literature, no relation could be confirmed between the concentration
lidocaine in the newborn and the interval between administration and partus.
Beside this, it is important to know the pharmacokinetics of lidocaine in
newborns. By research the pharmacokinetics of lidocaine in newborns, we can
estimate the duration of exposure to lidocaine and the estimated level of
lidocaine belonging to a specific time.
We aim to investigate the transmission of lidocaine from mother to child during
delivery and study the pharmacokinetics of lidocaine in newborns.

With this study we want to determine the concentration lidocaine in newborn
after partus using an episiotomy in relation to the concentration in mother.
Our secondary objectives are to look at the relation between the degree of
transmission of lidocaine to the newborns and the drug-delivery interval, and
the pharmacokinetical behaviour of lidocaine in newborn after transmission of
lidocaine during the partus.

Prospective observational cohort study

Women are asked for participation in the study and at the time the child is
delivered, about 100 microliter blood of the mother is obtained to measure a
lidocaine level. This risk is absent, when blood can obtained from an
intravenous line.
When the umbilical cord is clamped, venous and arterial blood will be obtained
from the umbilical cord. No burden is associated with this intervention.
Minimal 100 microliter blood of the neonate is obtained at five predefined
times. The burden for these neonates is minimal, because they will, according
current practice, obtain blood at five predefined times for determine glucose
curves.
There are no benefits for the participants. The result of the study may
contribute to increase of acknowledgement about drugs administered to pregnant
women, the risk of transmission to the child and the behaviour of lidocaine in
the neonate.