Labor analgesia and infant brain development

Association of epidural analgesia in labor with neurodevelopmental outcomes in premature infants born at <29 weeks of gestational age

OBJECTIVE

To explore associations between epidural administration to mothers in labor with neurodevelopmental outcomes at 3 years corrected age in preterm infants born <29 weeks gestational age.

STUDY DESIGN

Infants born <29 weeks gestational age between 2006 and 2012 were included. Our primary outcome was a composite of death or neurodevelopmental impairment at 3 years corrected age. Infants were divided into those whose mothers did or did not receive epidural analgesia in labor. Univariable and multivariable regression was used for analysis.

RESULTS

There were 548 infants in the no epidural analgesia group and 121 in the epidural analgesia group. The adjusted odds ratio (95%CI) of neurodevelopmental impairment or death in the epidural group was 1.25 (0.82-1.93). Propensity score-matched results were 1.32 (0.79-2.22).

CONCLUSION

Preterm infants born <29 weeks gestational age to mothers who received epidural analgesia during labor were not associated with poor neurodevelopmental outcomes at 3 years corrected age.

Endorphins, Sexuality, and Reproduction

Beta-endorphin is secreted from the hypothalamus and pituitary in both mother and newborn. The placenta produces numerous pituitary hormones from the third month of pregnancy, one of which is βE. It has been suggested that βE has a role in the appetitive and precopulatory phase of sexual behavior in animals. An increase in endorphin levels during sexual activity in humans may contribute to attachment and bonding between partners, but contradictory reports in the literature question the association between sexuality and βE levels. The level of βE also increases during pregnancy, rises in early labor, peaks in late labor, and drops in the postpartum period. This fluctuation provides natural analgesia, raises the pain threshold, decreases the sensation of pain, or suppresses pain, and decreases fear levels during labor and birth. Beta-endorphin also protects the fetus from hypoxia during labor and birth and potential neural damage by aiding blood flow to the brain under hypoxic conditions. It has been suggested that a variety of pharmacologic and nonpharmacologic complementary therapies, when used in pregnancy, labor, and birth, activate the opioid receptors in the CNS and alter the sensation of pain during labor and birth, affect the mother-child attachment and affect sexual function. These studies report contradictory results that will be discussed in this chapter.

Impact of maternal neuraxial labor analgesia exposure on offspring's neurodevelopment: A longitudinal prospective cohort study with propensity score matching

Background

Neuraxial analgesia is widely used to relieve labor pain; its effects on long-term neurodevelopment of offspring remain unclear. This study was designed to investigate the influence of maternal neuraxial labor analgesia on offspring mental development.

Methods

This was a predefined secondary analysis of a 2-year prospective longitudinal study. Nulliparous women with single-term cephalic pregnancy preparing for vaginal delivery self-selected neuraxial analgesia or not during labor. Mothers and their offspring were followed up 2 years later. children's mental development was assessed with the bayley scales of infant development. A multivariable logistic model was used to identify factors associated with below-average mental development (Mental Development Index <90).

Results

A Total of 508 pairs of mothers and children completed a 2-year follow-up. after propensity score matching, 387 pairs were included in the analysis. In both cohorts, the proportions with below-average mental development were slightly lower in children whose mothers received neuraxial labor analgesia, although not statistically significant [in the full cohort: 9.8 % (36/368) vs. 15.7% (22/140), P = 0.060; In the matched cohort: 8.3% (21/254) vs. 14.3% (19/133), P = 0.065]. A higher 2-year depression score (in the full cohort: Odds Ratio 1.15, 95% CI 1.08–1.22, P < 0.001; In the matched cohort: Odds Ratio 1.09, 95% CI 1.01–1.18, P = 0.037), but not neuraxial analgesia exposure, was associated with an increased risk of below-average mental development.

Conclusions

Maternal depression at 2 years was associated with the risk of below-average mental development, whereas maternal exposure to neuraxial labor analgesia was not.

Clinical Trial Registration

The study was registered with www.chictr.org.cn (ChiCTR-OCH-14004888) and ClinicalTrials.gov (NCT02823418).

Academic Detailing of Meperidine at a Teaching Hospital

Meperidine (Demerol) is an opiate analgesic that is not considered first-line therapy for most pain management indications because of concerns about its safety and efficacy. Inpatient data from a 417-bed community teaching hospital revealed high use of meperidine in oral, IM, and IV forms. A multifaceted academic detailing approach was employed to change prescribing behavior and decrease meperidine use. This approach included conducting two concurrent Medication Use Evaluations; Grand Rounds presentations for pharmacy staff, nurses, and medical residents; solicitation of opinion leaders; pocket and table-top cards; newsletter articles; and provision of pharmaceutical care. Comparing the number of meperidine doses dispensed per adjusted patient day before and after the intervention, use was reduced by 0.0966 doses per patient (P < 0.05: 95% CI, 0.0955 to 0.0977). The number of patients receiving meperidine was reduced by 2.43% (P < 0.05: 95% CI, 1.97 to 2.88). This translates into a relative reduction of 29.5% in patients receiving meperidine and a relative reduction of 31% in meperidine doses dispensed per patient after academic detailing initiatives vs before. Eighty-five percent of standard orders were changed to improve therapy; these changes included converting meperidine to morphine or hydromorphone, decreasing cumulative acetaminophen daily dosages, using controlled-release and immediate-release opioids for pain management when oral therapy was tolerated, and combining modalities with different mechanisms of action for synergy and to decrease potential adverse effects from larger dosages of single entities. Academic detailing of meperidine resulted in short-term changes in prescribing patterns and decreased meperidine use at this institution. Long-term implications for pain management have not yet been assessed.

The importance of ‘awareness’ for understanding fetal pain

Our understanding of when the fetus can experience pain has been largely shaped by neuroanatomy. However, completion of the cortical nociceptive connections just after mid-gestation is only one part of the story. In addition to critically reviewing evidence for whether the fetus is ever awake or aware, and thus able to truly experience pain, we examine the role of endogenous neuro-inhibitors, such as adenosine and pregnanolone, produced within the feto-placental unit that contribute to fetal sleep states, and thus mediate suppression of fetal awareness. The uncritical view that the nature of presumed fetal pain perception can be assessed by reference to the prematurely born infant is challenged. Rigorously controlled studies of invasive procedures and analgesia in the fetus are required to clarify the impact of fetal nociception on postnatal pain sensitivity and neural development, and the potential benefits or harm of using analgesia in this unique setting.

Postoperative pain management in obstetric anesthesia–new challenges and solutions

The current understanding of pain processing mechanisms, the different pharmacologic drugs, and other nonpharmacologic means that can be used to manage postobstetric operation pain are reviewed.

Does epidural analgesia during labour affect the neonate?

Focus has changed from the immediate postpartum condition to the more long-term outcome of the neonate with respect to the use of epidural analgesia in labour. Anaesthesiologists have been slow to respond to the demand for this information. Newer analgesic agents and techniques may offer some advantage to the neonate; however, extensive study is still needed.

Perinatal bupivacaine and infant behavior in rhesus monkeys

To assess the effect of perinatal epidural bupivacaine analgesia on infant behavioral development, bupivacaine (1.2 mg/kg) was administered to term-pregnant rhesus monkeys (treated, n = 11, procedural controls, n = 8) and infant behavior was evaluated for 1 year using a test battery including infant neurobehavioral tests, observation of spontaneous behavior, and structured cognitive testing. No adverse effects of bupivacaine were detected for neonatal neurobehavior, early cognitive abilities, or performance of cognitive tasks by older infants. Bupivacaine infants directed more, shorter fixations at visual stimuli during visual novelty preference testing. Observation of behavior maturation patterns showed that the increase in manipulatory activity that normally occurs at 2 months of age was delayed in bupivacaine infants, and the increase in motor disturbance behaviors that normally occurs at 10 months of age was prolonged. These results are interpreted in terms of life-history and brain maturation landmarks that appear at these ages. The data suggest that epidural bupivacaine does not cause neonatal abnormalities or specific cognitive deficits but can alter the normal course of behavioral development.