Pethidine Level in Jordanian Women and their Newborns during Labor after a Single Intravenous Dose - Abstract
Background: Since 1940, pethidine became the most widely used opioid for labor analgesia. However, pethidine administration may cause fetal distress especially if delivery occurred in a short time after administration and due to genetic variations between populations. Therefore,the aim of this study was to develop a validated and sensitive method for determination of pethidine in plasmafollowed by determination of plasma pethidine level in Jordanian women at different times duringand after labor and in the neonatal cord just after delivery.
Methods: Liquid Chromatography tandem mass spectrometry was developed to measure pethidine levels in plasma. Fifteen pregnant females agreed to enroll in the study and each signed an informed consent. All pregnant females received a single intravenous dose of 50 mg pethidine followed by withdrawing of blood samples at certain time points for the measurement of pethidine levels. In addition, umbilicalcord was collected for the same purpose.
Results: Due to fetal distress, three out of fifteen subjects (20%) dropped out of the study following pethidine administration and went through Caesarian section. Two of the three withdrawn cases had high maternal pethidine plasma levels. A negative correlation was found between pethidine bioavailability in the newborn and the dose-delivery duration (p<0.01). In addition, there was a negative correlation between maternal’s pethidine concentration and Apgar score (p<0.05).
Conclusion: The present study showed that single intravenous dose during labor cannot be considered safe in Jordanian population without an extensive study with larger sample size regarding pethidine route of administration and its metabolism.