Epidural analgesia for labor pain and its relationship to fever

Dexmedetomidine improves mitophagy and pyroptosis through the ALKBH5/FUNDC1 axis during epidural-related maternal fever

PURPOSE

Epidural analgesia has emerged as a commonly used method for relieving labor pain. However, epidural-related maternal fever (ERMF) is characterized by a high occurrence rate and can have detrimental consequences for the well-being of both the mother and the fetus. This study aimed to investigate the functional role and underlying mechanism of dexmedetomidine (DEX) in ERMF.

MATERIALS AND METHODS

Ropivacaine (ROP)-induced human umbilical vein endothelial cells (HUVECs) were treated with DEX and/or transfected with ALKBH5 or FUNDC1 overexpression plasmid. qPCR and Western blot were adopted for mitophagy and pyroptosis marker protein detection. Autophagosomes were observed through electron microscopy, Caspase-1/PI double-positive cells were determined using flow cytometry. Inflammation-related factors were quantified using ELISA. The N6-methyladenosine (m6A) modification of FUNDC1 mRNA was examined using methylated RNA immunoprecipitation (MeRIP) and the binding between ALKBH5 and FUNDC1 mRNA was confirmed by RNA immunoprecipitation (RIP).

RESULTS

In ROP-induced HUVECs, there was a significant upregulation in ALKBH5 and FUNDC1, resulting in a notable increase in inflammation, pyroptosis, and mitophagy. The administration of DEX demonstrated the ability to alleviate ROP-induced pyroptosis and promote protective mitophagy. Interestingly, DEX treatment significantly reduced the interaction between ALKBH5 and FUNDC1 mRNA, while simultaneously increasing the m6A level of FUNDC1 mRNA in ROP-treated cells. Moreover, the overexpression of FUNDC1 partially reversed the effects of ALKBH5 overexpression on mitophagy and pyroptosis in HUVECs.

CONCLUSIONS

DEX can promote mitophagy and inhibit pyroptosis through the ALKBH5/FUNDC1 axis in ERMF, indicating its potential as a therapeutic strategy for clinical ERMF treatment.

Maternal intrapartum fever during epidural labour analgesia: Incidence and influencing factors

BACKGROUND

The management and nursing care of women's temperature during delivery is an important part of clinical obstetrics. We aimed to evaluate maternal intrapartum fever during epidural labour analgesia to provide evidence for the management and care of women in labour.

METHODS

This study was conducted and reported according to the STROBE statement. Women in labour undergoing epidural labour analgesia in our hospital from 1 January 2021 to 31 August 2022 were retrospectively selected. The characteristics of women in labour with and without intrapartum fever were compared. Pearson correlation and logistic regression analysis were used to analyse the influencing factors of postpartum fever.

RESULTS

A total of 196 women in labour were included, the incidence of maternal intrapartum fever in women in labour undergoing epidural analgesia was 27.5%. Pearson correlation analyses showed that BMI, oxytocin use, labour duration, number of vaginal examinations, time from rupture of the foetal membranes to the end of labour and duration of epidural analgesia were all correlated with the occurrence of intrapartum fever (all P < 0.05). Logistic regression analyses indicated that body mass index ≥28 kg/m2 (OR = 1.825), oxytocin use (OR = 2.082), labour duration ≥9.2 h (OR = 2.613), number of vaginal examinations ≥8 (OR = 2.044-3.115), the time from rupture of the foetal membranes to the end of labour ≥250 min (OR = 2.766) and duration of epidural analgesia ≥300 min (OR = 3.106) were risk factors for intrapartum fever in women in labour undergoing epidural analgesia (all P < 0.05).

CONCLUSIONS

Maternal intrapartum fever in women in labour undergoing epidural analgesia is common and influenced by many factors. Nurses should take early preventive care measures according to these factors during epidural analgesia in labour.

Perinatal outcomes and risk factors for epidural analgesia-associated intrapartum maternal fever: a retrospective study

BACKGROUND

Epidural analgesia (EA) increases the risks of maternal fever during labor, which is associated with adverse maternal and neonatal outcomes, while the risk factors for epidural-associated fever and strategies for minimizing these effects remain limited.

METHODS

A total of 325 pregnant women were retrospectively analyzed who had attended our hospital for a vaginal in-hospital delivery, including 208 who voluntarily accepted EA and 117 who did not receive EA. During labor, 208 EA women were allocated to a fever group (n = 42, a tympanic temperature ≥37.5 °C during labor), and a no fever group (n = 166). The outcome measures included main maternal and neonatal outcomes, labor times, duration of EA and the total EA dosage administered.

RESULTS

42 out of 208 women given EA exhibited fever temperatures during labor, which were higher than in women who did not receive EA (20.19% vs. 0.85%). Maternal fever had an increased risks for conversion to surgery (adjusted odds ratio (AOR), 4.05; 95% CI, 1.44-11.39) and neonatal infections (5.13; 1.98-13.29) compared to the no fever group. While maternal fever did not increase the risks for assisted vaginal delivery, fetal distress or admission to the neonatal intensive care unit (NICU), it was predominantly associated with primiparity and lesser times of gravity. Frequent cervical examinations, the duration of first stage and total labor, and the duration of EA and its total dosage were positively correlated with the incidence of fever. Furthermore, after stratifying risk factors into subgroups, we found that more frequent cervical examinations (≥7 times) and longer duration of first stage (≥442.5 min), total labor time (≥490 min), EA (≥610.0 min) increased the risk for epidural-associated fever after adjustment for potential confounding factors.

CONCLUSIONS

EA increased the risk of intrapartum epidural-associated fever, which was correlated with adverse perinatal outcomes. Nulliparity, less times of gravidity, ≥7 cervical examinations, increased volume of the EA dosage, prolonged duration of EA and total labor time were risk factors for epidural-associated fever. The findings provide clinicians with insights and strategies to prevent epidural-associated fever more safely and effectively.

Epidural-Related Fever and Maternal and Neonatal Morbidity: A Systematic Review and Meta-Analysis

BACKGROUND

While epidural analgesia (EA) is associated with maternal fever during labor, the impact on the risk for maternal and/or neonatal sepsis is unknown.

OBJECTIVES

The aim of this systematic review was to investigate the effect of epidural-related intrapartum fever on maternal and neonatal outcomes.

METHODS

OVID MEDLINE, OVID Embase, the Cochrane Library, Cochrane Controlled Register of Trials, and clinical trial registries were searched for randomized controlled trials (RCT) and observational cohort studies from inception to November 2018. A total of 761 studies were identified with 100 eligible for full-text review. Only articles investigating the relationship between EA and maternal fever during labor were eligible for inclusion. Study quality was assessed using the Cochrane's Risk of Bias tool and National Institute of Health Quality Assessment Tool. Two meta-analyses - one each for the RCT and observational cohort groups - were performed using the random-effects model of Mantel-Haenszel to produce summary risk ratios (RR) with 95% CI.

RESULTS

Twelve RCTs and 16 observational cohort studies involving 579,157 parturients were included. RRs for maternal fever for the RCT and cohort analyses were 3.54 (95% CI 2.61-4.81) and 5.60 (95% CI 4.50-6.97), respectively. Meta-analyses of RR for maternal infection in both groups were infeasible given few occurrences. Meta-analysis of data from observational studies showed an increased risk for maternal antibiotic treatment in the epidural group (RR 2.60; 95% CI 1.31-5.17). For both analyses, neonates born to women with an epidural were not evaluated more often for suspected sepsis. Neither analysis reported an increased rate of neonatal bacteremia or neonatal antibiotic treatment after EA, although data precluded conclusiveness.

CONCLUSION

EA increases the risk of intrapartum fever and maternal antibiotic treatment. However, a definite conclusion on whether EA increases the risk for a proven maternal and/or neonatal bacteremia cannot be drawn due to the low quality of data. Further research on whether epidural-related intrapartum fever is of infectious origin or not is therefore needed.

Histologic chorioamnionitis as a consideration in the management of newborns of febrile mothers

INTRODUCTION

Chorioamnionitis (CA) presents a risk for neonatal sepsis, but its diagnosis remains a challenge. Maternal fever is often used as a clinical predictor of infection, but may be affected by other factors. There is no consensus among neonatologists regarding the length of treatment of babies born to febrile mothers with negative blood culture, but whose placentas are positive for the presence of histologic CA (HCA).

OBJECTIVES

A prospective observational cohort study was conducted on term infants to determine the association of HCA with C-reactive protein (CRP) and elevated immature/total neutrophil (I/T) ratio and other perinatal factors.

METHODS

I/T ratio, CRP, blood culture and placental pathology were performed on 100 infants born to mothers with temperature ≥ 100.4 °F. Placental pathology performed on 100 control infants born to afebrile mothers.

RESULTS

There was a significant association between HCA and maternal fever (MF). The presence of elevated CRP was associated with HCA. There was no significant association between HCA and anesthesia, mode of delivery, nor elevated I/T ratio.

CONCLUSIONS

Maternal fever is associated with HCA. The HCA in conjunction with an elevated CRP can guide the duration of antimicrobial therapy in infants born to febrile mothers.

Temperature management in the delivery room

After being in a relatively stable thermoneutral uterus for the whole of pregnancy, the newborn baby enters a cooling environment and might suffer significant heat loss and hypothermia in the first minutes of life. Alternatively, the fetus might face significant hyperthermia during and immediately after delivery if the mother is febrile. Hypothermia, particularly in preterm babies, is associated with increased morbidity and mortality. Hyperthermic babies have a worse short-term outcome, and hyperthermia can be particularly detrimental in association with intrapartum asphyxia and infection. Prevention and treatment of these variations in temperature are still developing and the efficacy of some strategies remains unclear. Nevertheless, one goal in the delivery room is to maintain the newborn baby's temperature within the physiologically optimum range.

Prevention of birth asphyxia: responding appropriately to cardiotocograph (CTG) traces

Birth asphyxia is a broad term that refers to intrapartum asphyxia sufficient to cause neurological damage in some newborns and, rarely, intrapartum or neonatal death. Cerebral palsy and long-term neurological complications such as learning difficulties and motor impairments may be due to causes other than birth asphyxia. Several intrapartum events may cause asphyxia (i.e. hypoxia and metabolic acidosis) leading to the likelihood of neurological injury. The cardiotocograph (CTG) is a screening tool that is used to assess fetal well-being during labour and to identify the possibility of asphyxia. Abnormality of the CTG, sometimes severe enough to be described as a pathological trace, is commonly termed 'fetal distress', although many fetuses with such traces may not have hypoxia and metabolic acidosis. In current practice, the events are appropriately termed 'pathological CTG trace' or 'acidotic pH' rather than 'fetal distress'. Accurate interpretation of CTG is essential, and it is important to recognize a fetus that shows a pathological CTG in labour that may imply possible hypoxia and birth asphyxia. Considering the wider clinical picture in interpreting the CTG, and taking timely and appropriate action based on the findings, may help prevent birth asphyxia.