Effect of early versus conventional epidural analgesia during labor on cytokine production

Epidural-related maternal fever: incidence, pathophysiology, outcomes, and management

Epidural-related maternal fever affects 15% to 25% of patients who receive a labor epidural. Two meta-analyses demonstrated that epidural-related maternal fever is a clinical phenomenon, which is unlikely to be caused by selection bias. All commonly used neuraxial techniques, local anesthetics with or without opioids, and maintenance regimens are associated with epidural-related maternal fever, however, the impact of each component is unknown. Two major theories surrounding epidural-related maternal fever development have been proposed. First, labor epidural analgesia may lead to the development of hyperthermia through a sterile (noninfectious) inflammatory process. This process may involve reduced activation of caspase-1 (a protease involved in cell apoptosis and activation of proinflammatory pathways) secondary to bupivacaine, which impairs the release of the antipyrogenic cytokine, interleukin-1-receptor antagonist, from circulating leucocytes. Detailed mechanistic processes of epidural-related maternal fever remain to be determined. Second, thermoregulatory mechanisms secondary to neuraxial blockade have been proposed, which may also contribute to epidural-related maternal fever development. Currently, there is no prophylactic strategy that can safely prevent epidural-related maternal fever from occurring nor can it easily be distinguished clinically from other causes of intrapartum fever, such as chorioamnionitis. Because intrapartum fever (of any etiology) is associated with adverse outcomes for both the mother and baby, it is important that all parturients who develop intrapartum fever are investigated and treated appropriately, irrespective of labor epidural utilization. Institution of treatment with appropriate antimicrobial therapy is recommended if an infectious cause of fever is suspected. There is currently insufficient evidence to warrant a change in recommendations regarding provision of labor epidural analgesia and the benefits of good quality labor analgesia must continue to be reiterated to expectant mothers.

Inflammation and Epidural-Related Maternal Fever: Proposed Mechanisms

Intrapartum fever is associated with excessive maternal interventions as well as higher neonatal morbidity. Epidural-related maternal fever (ERMF) contributes to the development of intrapartum fever. The mechanism(s) for ERMF has remained elusive. Here, we consider how inflammatory mechanisms may be modulated by local anesthetic agents and their relevance to ERMF. We also critically reappraise the clinical data with regard to emerging concepts that explain how anesthetic drug-induced metabolic dysfunction, with or without activation of the inflammasome, might trigger the release of nonpathogenic, inflammatory molecules (danger-associated molecular patterns) likely to underlie ERMF.

Sense of coherence and women׳s birthing outcomes: A longitudinal survey

BACKGROUND

in Western countries, caesarean section rates are increasing at an alarming rate. This trend has implications for women׳s health and calls into question the use of pathogenesis to frame maternity services. The theory of salutogenesis offers an alternative as it focuses on health rather than illness. Sense of coherence (SOC), the cornerstone of salutogenesis, is a predictive indicator of health. This study aimed to explore associations between pregnant women׳s SOC, their birthing outcomes and factors associated with SOC changes.

METHODS

a longitudinal survey was conducted where women completed a questionnaire in the antenatal and postnatal period. Questionnaire one provided information on SOC scores, Edinburgh Postnatal Depression Scale (EPDS) scores, Support Behaviour Inventory (SBI) scores, pregnancy choices and demographics. Questionnaire two provided information on SOC scores, EPDS scores and birthing outcomes.

FINDINGS

1074 women completed questionnaire one and 753 women completed questionnaire two. Compared to women with low antenatal SOC, women with high antenatal SOC were less likely to experience caesarean section (OR 0.437 95% CI 0.209-0.915) and more likely to experience assisted vaginal birth (AVB) (OR 3.108 95% CI 1.557-6.203). Higher birth satisfaction, higher antenatal EPDS scores and lower antenatal SOC were associated with an increase in SOC. Epidural, AVB and decreased birth satisfaction were associated with a decrease in SOC.

CONCLUSION

high sense of coherence in pregnant women is associated with half the likelihood of caesarean section compared to women with low sense of coherence. Women׳s sense of coherence is raised and lowered by degree of satisfaction with their births and lowered by some labour interventions.