Inflammation and Epidural-Related Maternal Fever: Proposed Mechanisms

Effects of epidural analgesia on intrapartum maternal fever and maternal outcomes: an updated systematic review and meta-analysis

OBJECTIVE

Epidural-related maternal fever in women is a common clinical phenomenon that leads to adverse consequences for mothers and neonates. The meta-analysis aimed to quantify the risk for intrapartum maternal fever after epidural analgesia (EA) stratified according to parity. The secondary objective was to investigate the association between EA and maternal outcomes.

METHODS

An electronic literature search of the Medline/PubMed, Embase, Cochrane Library, Wanfang Data, and China National Knowledge Infrastructure databases was performed to identify studies reporting the occurrence of intrapartum fever in parturients. Studies were reviewed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and meta-analysis was performed using Review Manager version 5.3.

RESULTS

Seventeen randomized controlled trials (RCTs) (5959 parturients) were included. Odds ratios for maternal fever in the analysis were 4.17 (95% confidence interval (CI) 2.93-5.94) and 5.83 (95% CI 4.96-6.87), respectively. Results of subgroup analysis according to parity were consistent. EA significantly prolonged the length of the first stage of labor (MD 34.52 [95% CI 12.13-56.91]) and the second stage of labor (MD 9.10 [95% CI 4.51-13.68]). Parturients who received EA were more likely to undergo instrumental delivery (OR 2.03 [95% CI 1.44-2.86]) and oxytocin augmentation (OR 1.45 [95% CI 1.12-1.88]). There were no differences in cesarean delivery rates between the EA and non-EA groups.

CONCLUSIONS

Parturients who received EA exhibited a higher incidence of intrapartum fever. Credibility of the subgroup analyses was low because the mixed group did not effectively represent multiparas.

Cooling treatment on the reduction of category II fetal tracings

OBJECTIVES

Epidural-related maternal fever increases the incidence of Category II fetal tracings. To compare the effectiveness of low-flow oxygen inhalation and cooling treatment for parturients with Category II fetal tracings caused by epidural-related maternal fever.

METHODS

We investigated 200 pregnant women who accepted epidural analgesia during labor and had body temperature exceeding 38 °C during labor. Among the patients, 99 and 101 were randomly allocated to receive cooling treatment group (control group) and oxygen inhalation (oxygen group), respectively. The primary outcome was the incidence of Category II fetal heart rate tracings.

RESULTS

The incidence of Category II fetal heart rate tracings in the control group was significantly higher than that in the oxygen group. However, no significant differences were noted between the two groups in terms of the Apgar scores; amniotic fluid turbidity; or maternal outcomes, including cesarean section rate, forceps delivery rate, lateral resection rate, manual removal of placenta rate, the amount of intrapartum hemorrhage, and hemorrhage at postpartum 2 h. Oxygen inhalation therapy was more effective than cooling treatment in reducing the incidence of Category II tracings.

CONCLUSION

Low-flow and short-term oxygen inhalation for parturients with epidural-related maternal fever reduces the incidence of Category II fetal heart rate tracings, but had no significant influence on the mode of delivery or neonatal outcomes.

In Situ Array Microextraction and Metabolic Profiling of Small Extracellular Vesicles to Guide and Monitor Maternal Delivery

The advantages of small extracellular vesicles (sEV) in disease management have become increasingly prominent, with the main challenge lying in meeting the demands of large-scale extraction and high-throughput analysis, a crucial aspect in the realm of precision medicine. To overcome this challenge, an engineered on-plate aptamer array (16×24 spots) is developed for continuous scale-up microextraction of plasma sEV and their in situ metabolic analysis using mass spectrometry. With this integrated array strategy, metabolic profiles of sEV are acquired from the plasma of 274 antenatal or postpartum women, reducing analysis time by half (7.5 h) and sample volume by 95% (only 0.125 µL usage) compared to the traditional suspension method. Moreover, using machine learning algorithms on sEV metabolic profiles, a risk score system is constructed that accurately assesses the need for epidural analgesia during childbirth and the likelihood of post-administration fever. The system, based on admission samples, achieves an impressive 94% accuracy. Furthermore, post-administration fever can be identified from delivery samples, reaching an overall accuracy rate of 88%. This work offers real-time monitoring of the childbirth process that can provide timely guidance for maternal delivery, underscoring the significance of sEV detection in large-scale clinical samples for medicine innovation and advancement.

Epidural analgesia and neonatal short-term outcomes during routine childbirth: a 10-year retrospective analysis from the national birth registry of Austria

BACKGROUND

Epidural analgesia (EA) is well-accepted for pain relief during labor. Still, the impact on neonatal short-term outcome is under continuous debate. This study assessed the outcome of neonates in deliveries with and without EA in a nationwide cohort.

METHODS

We analyzed the National Birth Registry of Austria between 2008 and 2017 of primiparous women with vaginal birth of singleton pregnancies. Neonatal short-term morbidity was assessed by arterial cord pH and base excess (BE). Secondary outcomes were admission to a neonatological intensive care unit, APGAR scores, and perinatal mortality. Propensity score-adjusted regression models were used to investigate the association of EA with short-term neonatal outcome.

RESULTS

Of 247,536 included deliveries, 52 153 received EA (21%). Differences in pH (7.24 vs. 7.25; 97.5% CI -0.0066 to -0.0047) and BE (-5.89±3.2 vs. -6.15±3.2 mmol/L; 97.5% CI 0.32 to 0.40) with EA could be shown. APGAR score at five minutes <7 was more frequent with EA (OR 1.45; 95% CI: 1.29 to 1.63). Admission to a neonatological intensive care unit occurred more often with EA (4.7% vs. 3.4%) with an OR for EA of 1.2 (95% CI: 1.14 to 1.26). EA was not associated with perinatal mortality (OR 1.33; 95% CI: 0.79 to 2.25).

CONCLUSIONS

EA showed no clinically relevant association with neonatal short-term outcome. Higher rates of NICU admission and APGAR score after five minutes <7 were observed with EA. The overall use of EA in Austria is low, and an investigation of causes may be indicated.

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.

Role of mitochondrial DNA level in epidural-related maternal fever: a single-centre, observational, pilot study

INTRODUCTION

Epidural analgesia has been associated with intrapartum maternal fever development. Epidural-related maternal fever (ERMF) is believed to be based on a non-infectious inflammatory reaction. Circulating cell-free mitochondrial deoxyribonucleic acid (mtDNA) is one of the possible triggers of sterile inflammatory processes; however, a connection has not been investigated so far. Therefore, this study aimed to investigate cell-free mtDNA alterations in women in labour with ERMF in comparison with non-febrile women.

MATERIAL AND METHODS

A total of 60 women in labour were assessed for maternal temperature every 4 h and blood samples were obtained at the beginning and after delivery. Depending on the analgesia and the development of fever (axillary temperature ≥ 37.5 °C), the women were allocated either to the group of no epidural analgesia (n = 17), to epidural analgesia no fever (n = 34) or to ERMF (n = 9). Circulating cell-free mtDNA was analysed in the maternal plasma for the primary outcome whereas secondary outcomes include the evaluation of inflammatory cytokine release, as well as placental inflammatory signs.

RESULTS

Of the women with epidural analgesia, 20% (n = 9) developed ERMF and demonstrated a decrease of circulating mtDNA levels during labour (p = 0.04), but a trend towards higher free nuclear DNA. Furthermore, women with maternal pyrexia showed a 1.5 fold increased level of Interleukin-6 during labour. A correlation was found between premature rupture of membranes and ERMF.

CONCLUSIONS

The pilot trial revealed an evident obstetric anaesthesia phenomenon of maternal fever due to epidural analgesia in 20% of women in labour, demonstrating counterregulated free mtDNA and nDNA. Further work is urgently required to understand the connections between the ERMF occurrence and circulating cell-free mtDNA as a potential source of sterile inflammation.

TRIAL REGISTRATION

NCT0405223 on clinicaltrials.gov (registered on 25/07/2019).

Fever in childbirth: a mini-review of epidural-related maternal fever

Fever during childbirth, which is often observed in clinical settings, is characterized by a temperature of 38°C or higher, and can occur due to infectious and non-infectious causes. A significant proportion of non-infectious causes are associated with epidural-related maternal fever during vaginal delivery. Therapeutic interventions are required because fever has adverse effects on both mother and newborn. Effective treatment options for ERMF are lacking. As it is difficult to distinguish it from intrauterine infections such as chorioamnionitis, antibiotic administration remains the only viable option. We mentioned the importance of interleukin-1 receptor antagonist in the sterile inflammatory fever pathway and the hormonal influence on temperature regulation during childbirth, an important factor in elucidating the pathophysiology of ERMF. This review spotlighted the etiology and management of ERMF, underscoring recent advancements in our understanding of hypothalamic involvement in thermoregulation and its link to sterile inflammation. We propose to deepen the understanding of ERMF within the broader context of autonomic neuroscience, aiming to foster the development of targeted therapies.

Clinical chorioamnionitis at term: definition, pathogenesis, microbiology, diagnosis, and treatment

Clinical chorioamnionitis, the most common infection-related diagnosis in labor and delivery units, is an antecedent of puerperal infection and neonatal sepsis. The condition is suspected when intrapartum fever is associated with two other maternal and fetal signs of local or systemic inflammation (eg, maternal tachycardia, uterine tenderness, maternal leukocytosis, malodorous vaginal discharge or amniotic fluid, and fetal tachycardia). Clinical chorioamnionitis is a syndrome caused by intraamniotic infection, sterile intraamniotic inflammation (inflammation without bacteria), or systemic maternal inflammation induced by epidural analgesia. In cases of uncertainty, a definitive diagnosis can be made by analyzing amniotic fluid with methods to detect bacteria (Gram stain, culture, or microbial nucleic acid) and inflammation (white blood cell count, glucose concentration, interleukin-6, interleukin-8, matrix metalloproteinase-8). The most common microorganisms are Ureaplasma species, and polymicrobial infections occur in 70% of cases. The fetal attack rate is low, and the rate of positive neonatal blood cultures ranges between 0.2% and 4%. Intrapartum antibiotic administration is the standard treatment to reduce neonatal sepsis. Treatment with ampicillin and gentamicin have been recommended by professional societies, although other antibiotic regimens, eg, cephalosporins, have been used. Given the importance of Ureaplasma species as a cause of intraamniotic infection, consideration needs to be given to the administration of antimicrobial agents effective against these microorganisms such as azithromycin or clarithromycin. We have used the combination of ceftriaxone, clarithromycin, and metronidazole, which has been shown to eradicate intraamniotic infection with microbiologic studies. Routine testing of neonates born to affected mothers for genital mycoplasmas could improve the detection of neonatal sepsis. Clinical chorioamnionitis is associated with decreased uterine activity, failure to progress in labor, and postpartum hemorrhage; however, clinical chorioamnionitis by itself is not an indication for cesarean delivery. Oxytocin is often administered for labor augmentation, and it is prudent to have uterotonic agents at hand to manage postpartum hemorrhage. Infants born to mothers with clinical chorioamnionitis near term are at risk for early-onset neonatal sepsis and for long-term disability such as cerebral palsy. A frontier is the noninvasive assessment of amniotic fluid to diagnose intraamniotic inflammation with a transcervical amniotic fluid collector and a rapid bedside test for IL-8 for patients with ruptured membranes. This approach promises to improve diagnostic accuracy and to provide a basis for antimicrobial administration.

Serum Magnesium Level as a Biomarker to Predict the Risk of Labor Epidural Anesthesia Associated Fever

Objective

Excessive pain will have adverse effects on the mother and fetus. Labor epidural analgesia greatly reduces the pain, which is widely carried out abroad. Labor epidural anesthesia-associated fever (LEAF) is the biggest problem for labor epidural anesthesia. This study aimed to evaluate the clinical value of serum magnesium levels to predict the LEAF.

Methods

Overall 528 singleton term-pregnant women who underwent labor epidural anesthesia in Fujian Provincial Maternity and Children's Health Hospital, affiliated hospital of Fujian Medical University from January 2019 to June 2019, were analyzed retrospectively. The serum magnesium level was detected using venous blood samples. The relationship between the serum magnesium level and LEAF was interpreted, and the optimal cut-off values of the serum magnesium level to predict LEAF were calculated.

Results

Overall, 65 (12.30%) participants had LEAF. And a higher rate of the bulging membrane, gestational hypertension, neonatal intensive care unit (NICU) admission, and the different mode of delivery was significantly associated with LEAF. Also, the serum magnesium level demonstrated higher significantly in presence of LEAF than absence (P<0.05). What is more, it indicated that the area under the receiver operating characteristic curve (AUC) for the serum magnesium level was 0.825, and an optimal cut-off of the serum magnesium level was 0.855 mg/dl. Furthermore, it demonstrated that the serum magnesium level had the highest OR (OR= 7.49; 95% CI (4.58-14.35)) (P<0.001). The bulging membrane is an independent risk factor presence of LEAF (OR = 1.55; 95% CI (1.01-2.43)) (P=0.038).

Conclusion

This study demonstrated that the baseline of serum magnesium can provide a suitable biomarker to predict LEAF. It can help to provide a useful target for LEAF treatment and enhance surveillance before fever.

Laboratory markers to identify acute histological chorioamnionitis in febrile parturients undergoing epidural analgesia: a retrospective study

BACKGROUND

This study aimed to investigate the effect of the pathological staging of acute histological chorioamnionitis (HCA) on laboratory indicators and to conduct further studies to reassess the threshold values used by clinicians to identify acute HCA in febrile parturients undergoing epidural analgesia.

METHODS

A retrospective study of febrile mothers receiving epidural analgesia at Nanjing Maternal and Child Health Care Hospital from January 1, 2018 to December 31, 2018. The participants were grouped by the progression of acute HCA, and the laboratory parameters were compared between groups. The ability of C-reactive protein (CRP), neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and monocyte-leukocyte ratio (M%), alone or in combination, to identify acute HCA in febrile parturients undergoing epidural analgesia was assessed using logistic regression and ROC curves.

RESULTS

The area under the curve (AUC) of the best logistic regression model predicting HCA climbed to 0.706 (CRP + MLR). Maternal CRP, NLR, and MLR significantly and progressively increased with the progression of acute HCA (p < 0.0001). Based on the ROC curves, the following thresholds were selected to define increased laboratory indicators for identifying acute HCA: CRP ≥ 6.90 mg/L, NLR ≥ 11.93, and MLR ≥ 0.57. In addition, the AUC of the best logistic regression model predicting HCA ≥ stage 2 was 0.710, so these inflammatory markers were more precise in predicting HCA ≥ stage 2.

CONCLUSION

Increased CRP (≥ 6.90 mg/L), NLR (≥ 11.93), and MLR (≥ 0.57) may help clinicians to identify early potential acute HCA in febrile parturients receiving epidural analgesia and to monitor progression to optimize clinical treatment options.

TRIAL REGISTRATION

The study was registered in the Chinese Clinical Trial Registry on November 24, 2021 ( http://www.chictr.org.cn , ChiCTR2100053554).

Factors associated with epidural-related maternal fever in low-risk term women: a systematic review

BACKGROUND

The underlying mechanism of epidural-related maternal fever (ERMF) is not fully understood. This systematic review aimed to identify factors associated with ERMF in low-risk, full-term women using neuraxial analgesia.

METHODS

PubMed, Embase, Web of Science, CENTRAL, and Wanfang Data were searched from inception to September 10, 2022 with no language restriction. Studies reported descriptive data regarding the factors associated with ERMF. A random effects model meta-analysis was used to pool the raw data of univariate analyses for each identified factor. Sensitivity and subgroup analyses were performed to explore possible sources of heterogeneity.

RESULTS

Eighteen observational studies involving 33 427 women were included, with 18 factors eligible for meta-analyses. Higher body mass index, baseline temperature, admission maternal interleukin-6 levels and white blood cell counts, nulliparity, increasing gestational age, longer duration of labor and rupture of membranes, increasing number of vaginal examinations, oxytocin use, higher birth weight, lower cervical dilation at initiation of analgesia, and longer analgesia duration were associated with increased risk of ERMF, while intermittent compared with continuous epidural dosing was associated with a decreased risk of ERMF (odds ratio 0.25, 95% CI 0.16 to 0.48, P < 0.001). However, heterogeneity among studies was high and the quality of evidence was low for these meta-analyses, except for intermittent epidural dosing.

CONCLUSIONS

Many factors are associated with ERMF but may not be independent or causal. Further study is needed to clarify the interactions of these factors in ERMF development and whether modification of these factors might influence risk of ERMF.

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.

Construction of a nomogram model for predicting infectious intrapartum fever

OBJECTIVES

To investigate influencing factors of intrapartum fever during vaginal delivery and to construct a prediction model for infectious intrapartum fever.

METHODS

A total of 444 patients with intrapartum fever admitted in Ningbo Women and Children's Hospital from January 2020 to December 2021 were enrolled. The clinical data and laboratory findings were compared between patients with infectious intrapartum fever and non-infectious intrapartum fever, and the factors associated with intrapartum fever were analyzed with a multivariate logistic regression model. A prediction nomogram model was constructed based on the factors of intrapartum fever and its predictive efficiency was evaluated by correction curve and receiver operator characteristic curve.

RESULTS

In the 444 cases, 182 (41.0%) had definite intrauterine infection and 262 (59.0%) had no infectious intrapartum fever. Univariate analysis showed that the length of hospital stay before induced labor, the time of induced abortion, misoprostol administration, autoimmune diseases, white blood cell count (WBC) and hypersensitive C-reactive protein (hs-CRP) levels were significantly different between the two groups (all P<0.05). Multivariate analysis showed that misoprostol administration and autoimmune diseases were protective factors (OR=0.31 and 0.36, both P<0.05) for infectious intrapartum fever, while high WBC and hs-CRP were risk factors (OR=1.20 and 1.09, both P<0.05). The area under the curve of nomogram model for predicting infectious intrapartum fever was 0.823, and the calibration curve validation showed that the predicted and measured values were in general agreement.

CONCLUSIONS

Multiple factors cause intrapartum fever. The nomogram model constructed in this study has good predictive accuracy for infectious intrapartum fever.

Risk factors for acute colonic pseudo-obstruction after caesarean section: A retrospective case-control study

BACKGROUND

Pregnancy and caesarean section are known to predispose to the development of acute colonic pseudo-obstruction (ACPO), a rare form of functional ileus of the distal large bowel. Pathogenesis of ACPO is likely influenced by pregnancy and childbirth and subsequent changes to hormonal, autonomic and metabolic physiology. Identifying pregnancy risk factors will assist with early identification, as the insidious onset postpartum often leads to delayed diagnosis and bowel ischaemia, perforation and sepsis.

AIMS

To establish pregnancy risk factors associated with the development of ACPO after caesarean section.

MATERIALS AND METHODS

A retrospective case-control study included 19 121 women undergoing caesarean between 1 January 2008 and 31 December 2016 at a tertiary referral hospital. Twenty-three cases of computerised tomography (CT)-diagnosed ACPO post-caesarean were identified from hospital medical records and imaging databases. Controls were matched for gestational and maternal age within one week of delivery with a ratio of 1:3.

RESULTS

The incidence of ACPO was one in 800 caesarean sections. ACPO was significantly more likely to occur in women who had been administered opioid analgesia in labour (odds ratio (OR) 4.67, P = 0.04), and a trend for increased estimated blood loss (OR 1.01, P = 0.01). There was no increased risk associated with emergency or elective caesarean classification, previous abdominal surgery, type of anaesthesia, duration of labour, oxytocin augmentation, intrapartum fever, hypertensive disorders, diabetes in pregnancy, antepartum haemorrhage, multiple gestation, fetal presentation or birthweight.

CONCLUSIONS

Risk factors for developing ACPO post-caesarean include opioid analgesia in labour and a trend for increased blood loss.

Association between epidural-related maternal fever and short-and long-term prognosis of parturients: A prospective observational study

We aimed to explore the association between epidural-related maternal fever (ERMF) and prognosis of parturients. 159 parturients who underwent vaginal delivery under labor epidural analgesia (LEA) received noninvasive continuous core body temperature monitoring. 122 of them completed the 42-day postpartum follow-up. Parturients with body temperature ≥38°C during labor were categorized as the Fever group, while the others were categorized as the No-Fever group. Compared to No-Fever group, Fever group had a greater proportion of primiparas, greater gestational age of parturients, and longer third stage of labor. The cesarean section and forceps delivery rates, and the amount of intrapartum hemorrhage in Fever group were significantly higher. There were no significant between-group differences with respect to puerperal infection, and amniotic fluid turbidity degree, neither significant between-group difference at 42-days postpartum. We found that ERMF was associated with some short-term outcomes. However, it showed no relation with long-term prognosis of the parturients at 42-days postpartum.

Maternal Fever Associated With Continuous Spinal Versus Epidural Labor Analgesia: A Single-Center Retrospective Study

BACKGROUND

Neuraxial labor analgesia is associated with elevations in maternal temperature; the mechanism responsible is unknown. Proposed mechanisms have included infection, altered thermoregulation, and inflammation, potentially triggered by local anesthetics. Studies of the association between neuraxial labor analgesia and maternal fever have focused on epidural analgesia, and there have been no comparisons of the rate of maternal fever between continuous spinal and epidural labor analgesia.

METHODS

We performed a retrospective study to compare the rate of maternal fever between patients who received continuous spinal versus epidural labor analgesia between June 2012 and March 2020. Each patient who received continuous spinal analgesia was matched to 2 patients who received epidural analgesia and had the same nulliparous status. The primary outcome of our study was the incidence of intrapartum maternal fever, which we defined as any temperature ≥38 °C before delivery and compared between the continuous spinal and epidural groups using Fisher exact test.

RESULTS

We identified 81 patients who received continuous spinal analgesia and 162 matched controls who received epidural analgesia. Demographic and obstetric characteristics of the patients were similar between groups. While the duration of analgesia did not significantly differ, there was markedly increased bupivacaine consumption in women with epidural analgesia. Eight of 81 (9.9%; 95% confidence interval [CI], 5.1-18.3) women with continuous spinal analgesia developed an intrapartum fever compared to 18 of 162 (11.1%; 95% CI, 7.1-16.9) of women with epidural analgesia ( P = .83; Fisher exact test).

CONCLUSIONS

There was no significant difference in the rate of maternal fever between women with continuous spinal compared to epidural labor analgesia. While the route of administration and dose of bupivacaine differs between epidural and spinal labor analgesia, they are titrated to produce similar levels of neuraxial blockade. Our results are consistent with a model in which epidural related maternal fever is due to altered thermoregulation from a central neuraxial block and argue against a direct effect of bupivacaine or fentanyl, although we cannot rule out a concentration-independent effect of bupivacaine or fentanyl or an inflammatory effect of the catheter itself. These retrospective results highlight the importance of prospective and mechanistic study of neuraxial analgesia-related maternal fever.

The effects of combined spinal-epidural analgesia and epidural anesthesia on maternal intrapartum temperature: a randomized controlled trial

Background

Labor epidural analgesia has been suggested to be associated with intrapartum fever. We designed this study to investigate the effects of epidural analgesia and combined spinal-epidural analgesia on maternal intrapartum temperature.

Methods

Four hundred healthy nullipara patients were randomly assigned to receive either epidural analgesia (EA group) or combined spinal-epidural analgesia (CSEA group). Maternal temperature was measured hourly after analgesia administration. The primary outcome was the incidence of maternal fever, and the secondary outcomes were the duration of analgesia, analgesia to full cervical dilation and analgesia to delivery. Neonatal outcomes and other basic labor events were also recorded.

Results

Maternal temperature gradually increased with time in both analgesia groups during labor. However, the CSEA group had a lower incidence of maternal fever, and a lower mean maternal temperature at 5 h, 6 h, and 9 h after analgesia. In addtion, the CSEA group also had a shorter time of analgesia duration, analgesia to full cervical dilation, analgesia to delivery, and less dose of epidural local anesthetic than the EA group.

Conclusion

Our findings suggest that combined spinal-epidural analgesia is associated with a lower risk of intrapartum fever than epidural analgesia.

Trial registration

ChiCTR1900026606. Registered on 16/10/2019.

Association of epidural analgesia during labor with neurodevelopment of children during the first three years: the Japan Environment and Children's Study

BACKGROUND

Epidural analgesia relives pain during labor. However, the long-term effects on neurodevelopment in children remain unclear. We explored associations between exposure to epidural analgesia during labor and childhood neurodevelopment during the first 3 years of life, in the Japan Environment and Children's Study (JECS), a large-scale birth cohort study.

METHODS

Pregnant women were recruited between January 2011 and March 2014, and 100,304 live births of singleton children born at full-term by vaginal delivery, and without congenital diseases were analyzed. Data on mothers and children were collected using a self-administered questionnaires and medical record transcripts. The children's neurodevelopment was repeatedly assessed for five domains (communication, gross motor, fine motor, problem solving, and personal-social), using the Ages and Stages Questionnaires, Third Edition, at six time points from age 6 to 36 months. After adjusting for potential confounders, the associations between exposure to epidural analgesia during labor and children's neurodevelopment at each time point were assessed.

RESULTS

Of the 42,172 children with valid data at all six time points, 938 (2.4%) were born to mothers who received epidural analgesia during labor. Maternal exposure to epidural analgesia was associated with neurodevelopmental delays during the first 3 years after birth. Delay risks in gross and fine motor domains were the greatest at 18 months (adjusted odds ratio (aOR) [95% confidence interval (CI)]: 1.40 [1.06, 1.84] and 1.54 [1.17, 2.03], respectively), subsequently decreasing. Delay risks in communication and problem-solving domains were significantly high at 6 and 24 months, and remained significant at 36 months (aOR [95% CI]: 1.40 [1.04, 1.90] and 1.28 [1.01, 1.61], respectively). Exposure to epidural analgesia was also associated with the incidence of problem solving and personal-social delays from 18 to 24 months old. Neurodevelopmental delay risks, except for communication, were dominant in children born to mothers aged ≥30 years at delivery.

CONCLUSIONS

This study showed that maternal exposure to epidural analgesia during labor was associated with neurodevelopmental delays in children during the first 3 years after birth.

Combined spinal-epidural analgesia and epidural analgesia induced maternal fever with a similar timing during labor-A randomized controlled clinical trial

Background

Both epidural and combined spinal-epidural (EA and CSEA) analgesia can induce intrapartum maternal fever. CSEA has a more rapid onset and wider nerve block than EA. Therefore, CSEA might have a different profile of intrapartum maternal fever, including higher temperatures or earlier occurrence. This randomized clinical trial was to determine whether CSEA could cause maternal fever earlier than EA.

Methods

A randomized, double-blind, controlled clinical trial was performed on 233 nulliparous full-term pregnant women during vaginal delivery. The pregnant women were randomly allocated into the EA group (n = 113) and the CSEA group (n = 120). The fever latent period, from analgesia start to fever occurrence, was the primary endpoint in this study. The temperature was measured every 30 min using an eardrum thermometer during labor analgesia. The fever was defined as an eardrum temperature of ≥38 °C.

Results

No difference was found in the maternal fever rate between the EA and the CSEA groups (10/113 vs. 7/120, P = 0.356). There was no significant difference in the fever latent period between the two groups (4.75 ± 0.86 h vs. 3.79 ± 2.2 h, p = 0.305). The temperatures at all points had no differences between EA and CSEA.

Conclusion

CSEA had a similar latent fever period as EA. A further study is warranted to confirm the similar characteristic between CSEA and EA in the development of intrapartum maternal fever.

Clinical trial registration

www.chictr.org.cn, identifier ChiCTR2000038793.

Interventions for the prevention or treatment of epidural-related maternal fever: a systematic review and meta-analysis

Background

Epidural-related maternal fever in women in labour has consequences for the mother and neonate. There has been no systematic review of preventive strategies.

Methods

RCTs evaluating methods of preventing or treating epidural-related maternal fever in women in active labour were eligible. We searched MEDLINE, EMBASE, CINAHL, Web of Science, CENTRAL, and grey literature sources were searched from inception to April 2021. Two review authors independently undertook study selection. Data extraction and quality assessment was performed by a single author and checked by a second. The Cochrane Risk of Bias 2 tool was used. Meta-analyses for the primary outcome, incidence of intrapartum fever, were performed using the DerSimonian and Laird random effects model to produce summary risk ratios (RRs) with 95% confidence intervals (95% CIs).

Results

Forty-two records, representing 34 studies, were included. Methods of reduced dose epidural reduced the incidence of intrapartum fever, but this was not statistically significant when six trials at high risk of bias were removed (seven trials; 857 participants; RR=0.83; 95% CI, 0.41–1.67). Alternative methods of analgesia and high-dose prophylactic systemic steroids reduced the risk of intrapartum fever compared with epidural analgesia. Prophylactic paracetamol was not effective.

Conclusions

There is no clear evidence to support the use of any individual preventative or therapeutic intervention for epidural-related maternal fever. Further research should focus on understanding the mechanism of fever development to enable RCTs of potential interventions to reduce the incidence of intrapartum fever development and the subsequent disease burden felt by the neonate.

Clinical trial registration

CRD42021246929.

Delivery, maternal and neonatal outcomes in nulliparous women with gestational diabetes undergoing epidural labour analgesia: a propensity score-matched analysis

OBJECTIVE

This study aimed to retrospectively analyse the influence of epidural labour analgesia (ELA) on delivery and maternal and neonatal outcomes in nulliparous women with gestational diabetes mellitus (GDM) using propensity score-matched analysis.

DESIGN

Retrospective cohort analysis.

SETTING

Primary care practices in a teaching hospital from March 2018 to October 2021.

PARTICIPANTS

A total of 816 delivery records of nulliparous women with GDM were collected and retrospectively analysed.

INTERVENTIONS

ELA and non-ELA (NELA) cohorts were assessed.

MAIN OUTCOME MEASURE

The primary outcome assessed was delivery type (spontaneous, assisted vaginal or caesarean). The secondary outcomes assessed included labour duration and maternal and neonatal outcomes.

RESULTS

A total of 137 propensity score-matched pairs of ELA and NELA patients were analysed. ELA was associated with a decreased rate of caesarean section (18.3% vs 46.0% in the ELA vs NELA cohort, respectively; p<0.05) and an increased occurrence of assisted vaginal delivery (35.8% vs 12.4% in the ELA vs NELA cohort, respectively; p<0.05). The duration of the first and total stages of labour was prolonged, the occurrence of postpartum fever increased, and the duration of hospital stay was shortened in those receiving ELA (all p<0.05). Additionally, neonatal birth weight, plasma glucose levels and neonatal macrosomia occurrence increased, while neonatal intensive care unit admissions and neonatal hypoglycaemia decreased in the ELA versus the NELA group (all p<0.05). With respect to other maternal and neonatal outcomes, both cohorts were similar.

CONCLUSIONS

The use of ELA decreases the rate of caesarean section and improves maternal and neonatal outcomes in nulliparous women with GDM.

TRIAL REGISTRATION NUMBER

ChiCTR-2000033091.

Risk factors of maternal intrapartum fever and the effect of fever duration on neonatal morbidity in different temperature

AIM

To investigate the clinical risk factors of intrapartum fever and explore the relationship between fever duration and neonatal morbidity of different fever peak.

METHODS

A case-control study was conducted, and 714 pregnant women were divided into fever and nonfever group. Multivariable logistic regression model was estimated to evaluate the risk factors for maternal intrapartum fever. Receiver operating characteristic curve was adopted to explore the relationship between fever duration and fetal distress of different fever peak to find the cut-off point, then the neonatal outcomes of women with fever ≥38°C in two groups of different fever duration were compared.

RESULTS

Epidural analgesia (odds ratio [OR]: 6.89, p < 0.001), longer time of membrane rupture (OR: 1.06, p < 0.001) and longer time of first stage of labor (OR: 1.04, p = 0.03) were considered as independent risk factors for maternal fever. For women with temperature <38°C, fever duration was not associated with fetal distress, whereas the women with temperature ≥38°C, fever duration longer than 93.5 min was a good predictor of fetal distress (Area under curve (AUC) = 0.82, p < 0.05). Further analysis showed that infants of women with fever peak ≥38°C and fever duration longer than 90 min had a higher rate of 1 min Apgar score <7 (15.5% vs. 2.2%, p = 0.03), assisted ventilation (29.6% vs. 11.1%, p = 0.02), and admission to neonatal ward (87.3% vs. 60.0%, p = 0.001).

CONCLUSIONS

Epidural analgesia, longer time of membrane rupture, and longer time of first stage of labor were considered as independent risk factors for maternal intrapartum fever. For women with fever ≥38°C, controlling fever time less than 90 min might be helpful to reduce neonatal morbidity.

Effects of labour analgesia with different concentrations of ropivacaine on maternal body temperature and inflammatory factor: A randomized controlled study

PURPOSE

To investigate the effect of different concentrations of ropivacaine on maternal temperature and inflammatory factors during epidural analgesia.

METHOD

One hundred and forty healthy term nulliparas were randomly assigned to receive epidural analgesia with either 0.1% ropivacaine (group H) or 0.068% ropivacaine (group L). Epidural sufentanil 0.3 μg/ml was added in both groups. Maternal tympanic temperature was measured at initiation of epidural analgesia (baseline temperature) and each hour thereafter. Maternal blood samples were taken at the time of epidural placement and 4 hours after analgesia to detect IL-6 and IL-1β serum concentrations. Visual analog scale pain scores, labour events and neonatal outcomes were recorded.

RESULTS

Epidural analgesia using 0.1% or 0.068% ropivacaine both achieved satisfactory pain relief. Increases in maternal body temperature and in IL-6 levels were observed in both groups, but there was no significant difference between the two groups. The incidence of maternal fever was similar between the two groups.

CONCLUSION

Maternal body temperature and serum inflammatory factors are similarly affected by 0.1% or 0.068% ropivacaine used during epidural analgesia use for labour pain relief.

Combined spinal-epidural anesthesia with acupoint injection for labor anesthesia reduces IL-1β/IL-10 ratio in maternal peripheral blood, umbilical cord blood and improves the labor outcomes: A prospective randomized controlled trial

BACKGROUND

This study aimed to investigate the effects of combined spinal-epidural anesthesia (CSEA) with acupoint injection (AI) on the maternal-fetal expression of interleukin-1β (IL-1β), interleukin-10 (IL-10), analgesia effect, and labor outcomes.

METHODS

A total of 360 healthy primiparas were randomized into the CSEA+AI group, the CSEA group, the AI group, and the control group (n = 90, each group) according to the labor analgesia methods.

RESULTS

Compared to the CSEA group, the CSEA+AI group had significantly lower visual analog scale (VAS) scores, adverse events, dose of ropivacaine/sufentanil, and shorter labor durations. The IL-1β/IL-10 ratio in maternal peripheral blood and umbilical cord blood was reduced in the CSEA+AI group compared with the CSEA group.

CONCLUSION

The combination of CSEA and AI can reduce the ratio of IL-1β/ IL-10 in maternal peripheral blood and umbilical cord blood, which can effectively relieve labor pain.

Interleukin-1 receptor antagonist, mode of analgesia and risk of Caesarean delivery after onset of labour: a Mendelian randomisation analysis

BACKGROUND

Lower circulating levels of the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1ra) are associated with intrapartum inflammation and epidural analgesia-related maternal fever, both of which increase the rate of obstetric interventions. We hypothesised that genetic variants determining IL-1ra levels would be associated with Caesarean delivery rates after the onset of labour.

METHODS

We performed Mendelian randomisation analyses in parous women ≥16 yr old who received either non-neuraxial or neuraxial analgesia for their first two labours (UK Biobank). We used an established genetic score (calculated as 0-4, determined by the presence/absence of rs6743376 and rs1542176 alleles), in which the complete absence of both alleles causes the lowest IL-1ra levels. The primary outcome was Caesarean delivery after the onset of labour (odds ratio [OR]: 95% confidence intervals).

RESULTS

There were 7731 women (mean [standard deviation] age at first birth: 25 [5] yr) who had complete genetic scores and delivery data. For women who received non-neuraxial analgesia, Caesarean delivery rates were different across allele scores (χ²=12.4; P=0.015): 104/596 (17.4%) women with zero allele score underwent Caesarean delivery, compared with 654/5015 (13.0%) with allele score ≥1 (OR 1.41; 1.12-1.77). For women who had neuraxial analgesia, Caesarean delivery was not different across allele scores, ranging from 18.1% to 20.8% (χ²=0.29; P=0.99). Caesarean delivery was independent of type of analgesia for 818/7731 (10.6%) women with zero allele scores (OR 0.93; 0.63-1.39), but was higher in women receiving neuraxial analgesia with allele scores ≥1 (OR 1.55; 1.35-1.79; P<0.001).

CONCLUSIONS

Mendelian randomisation analysis suggests that higher IL-1ra levels are associated with reduced Caesarean delivery rate. Neuraxial analgesia appears to disrupt this link.

CLINICAL TRIAL REGISTRATION

UK Biobank study 62745.

Study on perinatal-related factors of maternity and newborn in parturients with intrapartum fever in part of Eastern China: A cross-sectional study

Background

Maternal intrapartum fever has a serious impact on mother and child. However, the corresponding study seems to be in short.

Methods

The role of inflammatory cells in patients who were diagnosed with intrapartum fever lived in part of Eastern China was evaluated. The obstetrics outcomes, complete blood cell count (CBC) and thereby converted neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio, monocyte to lymphocyte ratio (MLR), and vaginal secretion were compared in different groups.

Results

Prepartum values of white blood cell (WBC), red blood cell (RBC), and hemoglobin (Hb) were all a little higher in the febrile group than in the afebrile group, and postpartum WBC in the afebrile group was still higher while postpartum RBC and Hb were inferior to non‐fever maternity. Postpartum NLR and MLR were all higher in the fever group but not preferred overtly difference before delivery. Additionally, the comparison of WBC, RBC, Hb, platelets, neutrophils, and monocytes in prepartum and postpartum all showed significant differences.

Conclusion

The parturition could bring about the value change of CBC and intrapartum fever might aggravate or alleviate this change. Besides, the intrapartum fever might not be caused mainly by infection and the difference between bacteria and fungus could reflect in the CBC.

Evaluation of Epidural Analgesia Use During Labor and Infection in Full-term Neonates Delivered Vaginally

IMPORTANCE

Quantification of potential consequences associated with the use of epidural analgesia during labor could help to improve the safety and quality of labor and delivery care for parturient women.

OBJECTIVE

To evaluate the association between epidural analgesia use during labor and neonatal infection in a large cohort of parturient women.

DESIGN, SETTING, AND PARTICIPANTS

This propensity score-matched cohort study was conducted at a university-affiliated hospital in Shanghai, China. Women at full-term pregnancy undergoing vaginal delivery between January 2013 and October 2018 were included in the study. Parturient women who were parous, experiencing premature delivery (gestational age <37 weeks), were pregnant with more than 1 fetus, or had experienced a stillbirth were excluded. Data were analyzed from October 2019 to June 2020.

EXPOSURES

The use of epidural analgesia during labor.

MAIN OUTCOMES AND MEASURES

The primary outcome was the incidence of neonatal infection, including neonatal sepsis, neonatal uncharacterized infection, neonatal pneumonia, and neonatal necrotizing enterocolitis reported in the medical record. Secondary outcomes included the incidence of maternal intrapartum fever and histologic chorioamnionitis.

RESULTS

Among 37 786 parturient women included (mean [SD] age, 29.5 [3.0] years), 19 968 (52.8%) received epidural analgesia during labor. In the propensity score-matched cohort (including 15 401 parturient women in each group), use of epidural analgesia was associated with a higher incidence of neonatal infection (absolute risk difference, 2.6%, 95% CI, 2.2%-3.0%; relative risk [RR], 2.43; 95% CI, 2.11-2.78), including higher incidence of sepsis (absolute risk difference, 0.1%, 95% CI, 0.1%-0.2%; RR, 3.50; 95% CI, 1.73-7.07) and uncharacterized infection (absolute risk difference, 2.2%, 95% CI, 1.9% to 2.6%; RR, 2.69; 95% CI, 2.30-3.15), compared with no epidural analgesia use. Use of epidural analgesia was also associated with greater incidence of maternal intrapartum fever (RR, 4.12; 95% CI, 3.78-4.50) and histologic chorioamnionitis (RR, 4.08; 95% CI, 3.59-4.64) compared with no epidural analgesia use.

CONCLUSIONS AND RELEVANCE

This cohort study found that use of epidural analgesia in full-term nulliparous women undergoing vaginal delivery was associated with an increased risk of neonatal infection, pending further investigation. These findings support efforts to further improve safety and quality of labor and delivery care for parturient women.

Is peripartum maternal fever alone a reliable predictor of neonatal sepsis? A single-centre, retrospective cohort study

AIM

To determine the incidence rate of early-onset neonatal sepsis (EONS) among term neonates (gestation greater than 37 weeks) admitted to the neonatal intensive care unit for suspected sepsis and the association of EONS with maternal fever (temperature greater than 38°C).

METHODS

A single-centre retrospective cohort study of all term neonates (gestation >37 weeks) admitted to and treated in the neonatal unit at the Townsville University Hospital between March 2015 and March 2020. Neonatal sepsis was confirmed with positive neonatal blood culture. Data on neonatal birth/stay and maternal pregnancy were collected from the electronic medical records and neonatal database.

RESULTS

Data from 737 neonates who were admitted for treatment of EONS were analysed. Sixty % (426) reported maternal intrapartum fever, with 1.1% (5) of neonates developing blood culture-proven sepsis. Forty % did not report intrapartum fever (311), with 3% (9) of neonates developing sepsis. As such, the sensitivity and specificity of maternal fever are 1.14% and 97%, respectively. The positive predictive value was 35.7%, and the negative predictive value was 40.1%. Fourteen neonates developed EONS, and all of them were symptomatic. Seventy-eight % (334/426) of the women in the febrile group received epidural analgesia compared to 5% (16/311) in the afebrile group. Of the 95 neonates born to women with chorioamnionitis, one (1.0%) of the neonates born to women with chorioamnionitis developed sepsis.

CONCLUSIONS

Intrapartum maternal fever is an unreliable predictor for EONS and leads to unnecessary antibiotic treatment. Symptoms in the neonate are a more reliable indicator of an ill neonate with blood culture-proven sepsis.

Association between epidural analgesia and indications for intrapartum caesarean delivery in group 1 of the 10-group classification system at a tertiary maternity hospital, Shanghai, China: a retrospective cohort study

Background

In this study, we aimed to determine whether epidural analgesia affects the indications for intrapartum caesarean delivery, such as foetal distress, dystocia, or maternal request, in nulliparous term women with spontaneous labour (Group 1 in the 10-Group Classification System).

Methods

We conducted a retrospective cohort study and collected data from the electronic medical records of deliveries performed in our institution between 1 January 2017 and 30 June 2017. Women conforming to the criterion of Group 1 according to the 10-Group Classification System were enrolled. We compared labour outcomes between women with and without epidural analgesia and analysed the association between epidural analgesia and indications for caesarean by using multivariate logistic regression analysis.

Results

A total of 3212 women met the inclusion criteria, and 2876 were enrolled in the final analyses. Women who received epidural analgesia had a significantly lower intrapartum caesarean delivery rate (16.0% vs. 26.7%, P < 0.001), higher rates of amniotomy (53.4% vs. 42.3%, P < 0.001) and oxytocin augmentation (79.5% vs. 67.0%, P < 0.001), and a higher incidence of intrapartum fever (≥38 °C) (23.3% vs. 8.5%, P < 0.001) than those who did not receive epidural analgesia. There were no significant differences between the groups for most indications, except a lower probability of maternal request for caesarean delivery (3.9% vs. 10.5%, P < 0.001) observed in women who received epidural analgesia than in those who did not. Epidural analgesia was revealed to be associated with a decreased risk of maternal request for caesarean delivery (adjusted odds ratio [aOR], 0.30; 95% confidence interval [CI], 0.22–0.42; P < 0.001); however, oxytocin augmentation was related to an increased risk of maternal request (aOR, 2.34; 95%CI, 1.47–3.75; P < 0.001). Regarding the reasons for the maternal request for caesarean delivery, significantly fewer women complained of pain (0.5% vs. 4.6%, P < 0.001) or had no labour progress (1.3% vs. 3.6%, P < 0.001) among those who received analgesia.

Conclusions

Among the women in Group 1, epidural analgesia was associated with a lower intrapartum caesarean delivery rate, which may be explained by a reduction in the risk of maternal request for an intrapartum caesarean delivery.

Nomogram for perinatal prediction of intrapartum fever: a retrospective case-control study

Objective

To explore the risk factors for intrapartum fever and to develop a nomogram to predict the incidence of intrapartum fever.

Methods

The general demographic characteristics and perinatal factors of 696 parturients who underwent vaginal birth at the Affiliated Hospital of Xuzhou Medical University from May 2019 to April 2020 were retrospectively analysed. Data was collected from May 2019 to October 2019 on 487 pregnant women who formed a training cohort. A multivariate logistic regression model was used to identify the independent risk factors associated with intrapartum fever during vaginal birth, and a nomogram was developed to predict the occurrence. To verify the nomogram, data was collected from January 2020 to April in 2020 from 209 pregnant women who formed a validation cohort.

Results

The incidence of intrapartum fever in the training cohort was found in 72 of the 487 parturients (14.8%), and the incidence of intrapartum fever in the validation cohort was 31 of the 209 parturients (14.8%). Multivariate logistic regression analysis showed that the following factors were significantly related to intrapartum fever: primiparas (odds ratio [OR] 2.43; 95% confidence interval [CI] 1.15–5.15), epidural labour analgesia (OR 2.89; 95% CI 1.23–6.82), premature rupture of membranes (OR 2.37; 95% CI 1.13–4.95), second stage of labour ≥ 120 min (OR 4.36; 95% CI 1.42–13.41), amniotic fluid pollution degree III (OR 10.39; 95% CI 3.30–32.73), and foetal weight ≥ 4000 g (OR 7.49; 95% CI 2.12–26.54). Based on clinical experience and previous studies, the duration of epidural labour analgesia also appeared to be a meaningful factor for intrapartum fever; therefore, these seven variables were used to develop a nomogram to predict intrapartum fever in parturients. The nomogram achieved a good area under the ROC curve of 0.86 and 0.81 in the training and in the validation cohorts, respectively. Additionally, the nomogram had a well-fitted calibration curve, which also showed excellent diagnostic performance.

Conclusion

We constructed a model to predict the occurrence of fever during childbirth and developed an accessible nomogram to help doctors assess the risk of fever during childbirth. Such assessment may be helpful in implementing reasonable treatment measures.

Trial registration

Clinical Trial Registration: (www.chictr.org.cnChiCTR2000035593)

Epidural Dexmedetomidine for Prevention of Intrapartum Fever During Labor Analgesia: A Randomized Controlled Trial

INTRODUCTION

Intrapartum fever occurs frequently during labor. The purpose of this study was to investigate the effects of epidural dexmedetomidine on maternal temperature, pain score and adverse effects during labor analgesia.

METHODS

A total of 600 full-term primiparous parturients were randomly divided into two groups. The dexmedetomidine group (Group Dex, n = 300) received 0.1% ropivacaine with 0.5 µg/mL dexmedetomidine for epidural analgesia during labor, while the control group (Group C, n = 300) received 0.1% ropivacaine alone. The maternal temperature, visual analogue scale (VAS) and Ramsay sedation score (RSS) were recorded, and the systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were monitored. Side effects, if any, were also recorded.

RESULTS

The incidence of intrapartum fever was lower in Group Dex than in Group C (4.1% vs. 8.7%, χ2 = 5.07, P = 0.024). VAS values from the time of 3 cm cervical dilatation to 10 cm cervical dilatation were also lower in Group Dex than in Group C (1.0 ± 0.9 vs. 1.3 ± 0.7, t = 3.62, P < 0.001; 2.8 ± 0.8 vs. 3.3 ± 0.8, t = 8.09, P < 0.001; 3.1 ± 0.9 vs. 3.3 ± 0.8, t = 3.88, P < 0.001; 3.6 ± 0.8 vs. 4.1 ± 1.0, t = 5.86, P < 0.001, respectively). HR from the time of 3 cm cervical dilatation to 10 cm cervical dilatation was lower during labor in Group Dex than in Group C (80.0 ± 4.3 vs. 83.1 ± 5.4 beats/min, t = 7.58, P < 0.001; 81.1 ± 4.0 vs. 83.7 ± 5.5 beats/min, t = 6.48, P < 0.001; 78.9 ± 5.4 vs. 81.5 ± 6.3 beats/min, t = 5.41, P < 0.001; 83.1 ± 5.3 vs. 84.8 ± 5.6 beats/min, t = 3.75, P < 0.001, respectively), while SBP and DBP were similar between the two groups. The incidence of adverse events during labor was also similar between the two groups.

CONCLUSION

The present study showed that dexmedetomidine could reduce the incidence of intrapartum fever and relieve pain during labor without increasing adverse events.

TRIAL REGISTRATION

ChiCTR-OPC-16008548.

Potential impact of epidural labor analgesia on the outcomes of neonates and children

This review summarizes recent evidences regarding the potential influences of epidural labor analgesia (ELA) on the outcomes of neonates and children. Terms and relevant words including “ELA,” “ELA and neonatal outcomes,” “ELA and children's development,” and “ELA and children's neurocognitive development” were used to search articles published in PubMed database up to October 2019. Original articles and reviews regarding potential influences of ELA on neonates and children were identified. Relevant references of the selected articles were also screened. The anesthetics used during ELA can be absorbed, enter the fetus, and produce neonatal depression; however, these effects are less severe than those during systematic opioid analgesia. The impact of anesthetic exposure during ELA on children's neurodevelopment has not been fully studied, but would be mild if any. ELA increases the risk of intrapartum maternal fever; the latter may be harmful to neonatal outcomes. The use of ELA may increase birth injury by increasing instrumental delivery, although long-term adverse events are rare. On the other hand, ELA may reduce maternal depression and, thus, produce favorable effects on neurocognitive development in childhood; but evidences are still lacking in this aspect. ELA may produce both favorable and unfavorable effects on neonates and children. These effects should be discussed with parturient women before making decisions. The potential harmful effects should be carefully managed. The overall impacts of ELA on neonatal and children's outcomes need to be studied further.

Clinical chorioamnionitis at term X: microbiology, clinical signs, placental pathology, and neonatal bacteremia - implications for clinical care

OBJECTIVES

Clinical chorioamnionitis at term is considered the most common infection-related diagnosis in labor and delivery units worldwide. The syndrome affects 5-12% of all term pregnancies and is a leading cause of maternal morbidity and mortality as well as neonatal death and sepsis. The objectives of this study were to determine the (1) amniotic fluid microbiology using cultivation and molecular microbiologic techniques; (2) diagnostic accuracy of the clinical criteria used to identify patients with intra-amniotic infection; (3) relationship between acute inflammatory lesions of the placenta (maternal and fetal inflammatory responses) and amniotic fluid microbiology and inflammatory markers; and (4) frequency of neonatal bacteremia.

METHODS

This retrospective cross-sectional study included 43 women with the diagnosis of clinical chorioamnionitis at term. The presence of microorganisms in the amniotic cavity was determined through the analysis of amniotic fluid samples by cultivation for aerobes, anaerobes, and genital mycoplasmas. A broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry was also used to detect bacteria, select viruses, and fungi. Intra-amniotic inflammation was defined as an elevated amniotic fluid interleukin-6 (IL-6) concentration ≥2.6 ng/mL.

RESULTS

(1) Intra-amniotic infection (defined as the combination of microorganisms detected in amniotic fluid and an elevated IL-6 concentration) was present in 63% (27/43) of cases; (2) the most common microorganisms found in the amniotic fluid samples were Ureaplasma species, followed by Gardnerella vaginalis; (3) sterile intra-amniotic inflammation (elevated IL-6 in amniotic fluid but without detectable microorganisms) was present in 5% (2/43) of cases; (4) 26% of patients with the diagnosis of clinical chorioamnionitis had no evidence of intra-amniotic infection or intra-amniotic inflammation; (5) intra-amniotic infection was more common when the membranes were ruptured than when they were intact (78% [21/27] vs. 38% [6/16]; p=0.01); (6) the traditional criteria for the diagnosis of clinical chorioamnionitis had poor diagnostic performance in identifying proven intra-amniotic infection (overall accuracy, 40-58%); (7) neonatal bacteremia was diagnosed in 4.9% (2/41) of cases; and (8) a fetal inflammatory response defined as the presence of severe acute funisitis was observed in 33% (9/27) of cases.

CONCLUSIONS

Clinical chorioamnionitis at term, a syndrome that can result from intra-amniotic infection, was diagnosed in approximately 63% of cases and sterile intra-amniotic inflammation in 5% of cases. However, a substantial number of patients had no evidence of intra-amniotic infection or intra-amniotic inflammation. Evidence of the fetal inflammatory response syndrome was frequently present, but microorganisms were detected in only 4.9% of cases based on cultures of aerobic and anaerobic bacteria in neonatal blood.

Risk Factors and Safety Analyses for Intrapartum Fever in Pregnant Women Receiving Epidural Analgesia During Labor

Background

We aimed to explore the factors leading to epidural-related maternal fever and the influence of intrapartum fever on neonates.

Material/Methods

A retrospective analysis was performed on data from pregnant women who received epidural analgesia during labor. The primary aim was to determine the influence of epidural labor analgesia on the incidence of intrapartum fever in pregnant women. The secondary aim was to determine the influence of intrapartum fever on neonates.

Results

Logistic regression analysis showed that premature rupture of membranes (OR=2.008, 95% CI: 1.551–2.600), vaginal examination performed more than 6 times (OR=1.681, 95% CI: 1.286–2.197), long duration of labor (OR=1.090, 95% CI: 1.063–1.118), and long time from rupture of membranes to delivery (OR=1.048, 95% CI: 1.010–1.087) were all risk factors for intrapartum fever in pregnant women with epidural labor analgesia. Regarding the secondary research outcome, the incidence of intrapartum fever was significantly associated with the number of neonates with Apgar score of 10 delivered from pregnant women with epidural labor analgesia (P<0.05). There was no statistically significant difference in the transfer rate of newborns to the Neonatal Intensive Care Unit (NICU) (P>0.05).

Conclusions

Premature rupture of membranes, vaginal examination performed more than 6 times, long duration of labor, and long time from rupture of membranes to delivery are all factors raising the risk of fever during epidural labor analgesia. Although intrapartum fever in the mothers had a significant influence on the number of neonates with Apgar score of 10, it did not affect the outcome of neonates in terms of NICU transfer rate.

Time- and dose-dependent correlations between patient-controlled epidural analgesia and intrapartum maternal fever

Background

To investigate the relationship between intrapartum maternal fever and the duration and dosage of patient-controlled epidural analgesia (PCEA).

Methods

This observational study included 159 pregnant women who voluntarily accepted PCEA. During labor, patients with body temperature ≥ 38 °C were classified into the Fever group, (n = 42), and those with body temperature < 38 °C were classified into the No-fever group (n = 117). The outcome measures included the duration of PCEA, number of PCEA, and total PCEA amount. Body temperature and parturient variables, including interpartum fever status and the duration of any fever were monitored.

Results

The total PCEA duration and total PCEA amount in the Fever group were significantly higher than the corresponding values in the No-fever group (both, p < 0.05). The duration of fever was weakly correlated with the duration of PCEA (R² = 0.08) and the total PCEA amount (R² = 0.05) (both, p < 0.05). The total and effective PCEA were higher in the Fever group than in the No-fever group (both, p < 0.05). The total PCEA duration and total PCEA amount were positively correlated with the incidence of fever (both, p < 0.05). The diagnostic cutoff value for fever was 383 min, with a sensitivity of 78.6% and specificity of 57.3%. The mean temperature-time curves showed that parturients who developed fever had a steeper rise in temperature.

Conclusions

This study showed that there were weak time- and dose-dependent correlations between PCEA and maternal fever during delivery. A total PCEA duration exceeding 6.3 h was associated with an increase in the duration of maternal intrapartum fever.

The relationship between epidural analgesia and intrapartum maternal fever and the consequences for maternal and neonatal outcomes: a prospective observational study

AIM

To use continuous real-time monitoring of maternal core body temperature during labor and investigate the association between epidural analgesia, intrapartum maternal fever, and maternal and neonatal outcomes.

METHODS

Among 201 pregnant women attending our institution for a vaginal in-hospital delivery, 159 women received epidural analgesia and 42 women did not receive epidural analgesia. Women's core body temperature was continuously monitored for the duration of labor using a smartphone/iPad-connected wireless thermometer positioned in an axilla. The primary outcome was a change in maternal core body temperature during labor. Among women receiving epidural analgesia, maternal and neonatal outcomes were compared in women who developed an intrapartum fever and those who had no intrapartum temperature elevation.

RESULTS

Of the women receiving epidural analgesia, 26.4% (n = 42/159) developed intrapartum fever ≥38 °C compared to 7.1% (n = 3/42) of women not receiving epidural analgesia. Among those receiving epidural analgesia, women who developed intrapartum fever had a significantly longer first stage of labor and a higher incidence of cesarean section, assisted vaginal delivery, intrapartum hemorrhage, and turbid amniotic fluid compared to women with no intrapartum temperature elevation. Neonates of women who developed intrapartum fever had lower 1- and 5-min Apgar scores compared to neonates of women with no intrapartum temperature elevation; however, the difference was not significant.

CONCLUSION

This study used a precise and accurate method to monitor core body temperature among women receiving epidural analgesia. Results showed that the use of epidural analgesia during labor was associated with intrapartum maternal fever in all stages of labor. Fever after epidural analgesia was associated with adverse maternal outcomes, independent of neonatal complications.

Concerned topics of epidural labor analgesia: labor elongation and maternal pyrexia: a systematic review

Objective:

Labor is a complex process and labor pain presents challenges for analgesia. Epidural analgesia (EA) has a well-known analgesic effect and is commonly used during labor. This review summarized frequently encountered and controversial problems surrounding EA during labor, including the labor process and maternal intrapartum fever, to build knowledge in this area.

Data sources:

We searched for relevant articles published up to 2019 in PubMed using a range of search terms (eg, “labor pain,” “epidural,” “analgesia,” “labor process,” “maternal pyrexia,” “intrapartum fever”).

Study selection:

The search returned 835 articles, including randomized control trials, retrospective cohort studies, observational studies, and reviews. The articles were screened by title, abstract, and then full-text, with a sample independently screened by two authors. Thirty-eight articles were included in our final analysis; 20 articles concerned the labor process and 18 reported on maternal pyrexia during EA.

Results:

Four classic prospective studies including 14,326 participants compared early and delayed initiation of EA by the incidence of cesarean delivery. Early initiation following an analgesia request was preferred. However, it was controversial whether continuous use of EA in the second stage of labor induced adverse maternal and neonatal outcomes due to changes in analgesic and epidural infusion regimens. There was a high incidence of maternal pyrexia in women receiving EA and women with placental inflammation or histologic chorioamnionitis compared with those receiving systemic opioids.

Conclusions:

Early EA (cervical dilation ≥1 cm) does not increase the risk for cesarean section. Continuous epidural application of low doses of analgesics and programmed intermittent epidural bolus do not prolong second-stage labor duration or impact maternal and neonatal outcomes. The association between EA and maternal pyrexia remains controversial, but pyrexia is more common with EA than without. A non-infectious inflammatory process is an accepted mechanism of epidural-related maternal fever.

Association Between Epidural Analgesia During Labor and Risk of Autism Spectrum Disorders in Offspring

IMPORTANCE

Although the safety of labor epidural analgesia (LEA) for neonates has been well documented, the long-term health effects of LEA on offspring remain to be investigated.

OBJECTIVE

To assess the association between maternal LEA exposure and risk of autism spectrum disorders (ASDs) in offspring.

DESIGN, SETTING, AND PARTICIPANTS

Data for this retrospective longitudinal birth cohort study were derived from electronic medical records from a population-based clinical birth cohort. A total of 147 895 singleton children delivered vaginally between January 1, 2008, and December 31, 2015, in a single integrated health care system were included. Children were followed up from the age of 1 year until the first date of the following occurrences: clinical diagnosis of ASD, last date of health plan enrollment, death, or the study end date of December 31, 2018.

EXPOSURES

Use and duration of LEA.

MAIN OUTCOMES AND MEASURES

The main outcome was clinical diagnosis of ASD. Cox proportional hazards regression analysis was used to estimate the hazard ratio (HR) of ASD associated with LEA exposure.

RESULTS

Among the cohort of 147 895 singleton children (74 425 boys [50.3%]; mean [SD] gestational age at delivery, 38.9 [1.5] weeks), 109 719 (74.2%) were exposed to maternal LEA. Fever during labor was observed in 13 055 mothers (11.9%) in the LEA group and 510 of 38 176 mothers (1.3%) in the non-LEA group. Autism spectrum disorders were diagnosed in 2039 children (1.9%) in the LEA group and 485 children (1.3%) in the non-LEA group. After adjusting for potential confounders, including birth year, medical center, maternal age at delivery, parity, race/ethnicity, educational level, household income, history of comorbidity, diabetes during pregnancy, smoking during pregnancy, preeclampsia or eclampsia, prepregnancy body mass index, gestational weight gain, gestational age at delivery, and birth weight, the HR associated with LEA vs non-LEA exposure was 1.37 (95% CI, 1.23-1.53). Relative to the unexposed group, the adjusted HR associated with LEA exposure of less than 4 hours was 1.33 (95% CI, 1.17-1.53), with LEA exposure of 4 to 8 hours was 1.35 (95% CI, 1.20-1.53), and with LEA exposure of more than 8 hours was 1.46 (95% CI, 1.27-1.69). Within the LEA group, there was a significant trend of ASD risk associated with increasing duration of LEA exposure after adjusting for covariates (HR for linear trend, 1.05 [95% CI, 1.01-1.09] per 4 hours). Adding fever to the model did not change the HR estimate associated with LEA exposure (adjusted HR for LEA vs non-LEA, 1.37 [95% CI, 1.22-1.53]).

CONCLUSIONS AND RELEVANCE

This study suggests that maternal LEA may be associated with increased ASD risk in children. The risk appears to not be directly associated with epidural-related maternal fever.

Association of lymphocyte count and incidence of maternal fever in epidural analgesia-involved labor

Background

Evidence showed that the use of epidural analgesia increased the risk of maternal fever during labor, and the potential mechanisms involved inflammation. Lymphocyte played a role in the inflammatory responses, and lymphopenia predicted adverse outcomes for patients. The aim of this study was to investigate whether lymphocyte count was associated with the incidence of intrapartum fever in nulliparous women undergoing vaginal delivery.

Methods

In this retrospective cohort study, electronic medical record data at the International Peace Maternity and Child Health Hospital (IPMCH, Shanghai, China) between 2012 and 2017 were extracted. The primary outcome of this study was baseline lymphocyte count in febrile and afebrile parturients who received labor epidural analgesia. Other confounding factors associated with the development of intrapartum fever were analyzed using multivariable logistic regression.

Results

The final study population consisted of 36,562 parturients, of whom 18,952 (51.8%) received labor epidural analgesia. Labor epidural analgesia was associated with an increased risk of maternal fever [relative risk: 4.55; 95% confidence interval (CI): 4.16–4.98; P<0.001]. Among the parturients who received epidural analgesia, both baseline lymphocyte count and lymphocyte percentage were lower in the febrile patients than those in the afebrile patients (P<0.001; P=0.015). The lower (<1.1×10⁹/L) baseline lymphocyte was associated with a higher risk of maternal fever (adjusted odds ratio: 1.30, 95% CI: 1.14–1.48; P<0.001).

Conclusions

Our results suggested that lower lymphocyte baseline indicated an increased risk of maternal fever during epidural analgesia-involved labor. Further studies are needed to confirm the findings and determine the potential mechanisms.

Epidural Fever: Hiding in the Shadows

Recent research has focused on inflammation and oxidative stress that is seen in women developing intrapartum fever. The interleukin-6 (IL-6) levels have been found to be elevated in women who receive epidural analgesia and become febrile. This suggests that the epidural itself induces an inflammatory response and it is not a physiologic process of labour. Similar findings with additional proinflammatory mediators and reactive oxygen species seem to support this theory. Epidural analgesia also affects the body’s thermoregulatory mechanisms. It causes an increase in shivering and appears to be associated with a decrease in heat dissipation via sweating and hyperventilation, most likely because of blockade of the sympathetic stimulation. Considering these factors, it is probable that epidurals do contribute to the development of the associated fever. There remains the possibility that subclinical chorioamnionitis might be the underlying cause of a subset of maternal intrapartum fevers. In summary, histologic chorioamnionitis and epidural analgesia appear to be the independent contributors to intrapartum fever.

Control central de la temperatura corporal y sus alteraciones: fiebre, hipertermia e hipotermia

Introducción. En mamíferos, el control de la temperatura corporal es vital. El estado de consciencia y control motor en humanos, ocurren a una temperatura de 37°C y las desviaciones pueden alterar las propiedades celulares, generando disfunciones fisiológicas. En especies como los roedores (su relación área de superficie/volumen facilita la pérdida de calor) mantienen temperaturas basales cercanas a los 30°C. Distinto es con animales como los paquidermos, cuya temperatura es menor comparada con los humanos. El objetivo es identificar los aspectos fisiológicos de la termorregulación. Descripción de temas tratados. Revisión descriptiva de la literatura de artículos publicados en diferentes bases de datos. La termorregulación es la capacidad del cuerpo para establecer y mantener su temperatura, regulando producción y pérdida de calor para optimizar la eficiencia de procesos metabólicos. El protagonismo lo tiene el sistema nervioso central y su control neuro-hormonal en múltiples niveles. El centro regulador térmico está en el hipotálamo anterior. Este recibe información de los receptores de grandes vasos, vísceras abdominales, médula espinal y de la sangre que perfunde el hipotálamo. Cuando aumenta la temperatura central, el termorregulador activa fibras eferentes del sistema nervioso autónomo, provocando pérdida de calor por convección y evaporación. Ante el descenso de temperatura, la respuesta es disminuir la pérdida de calor (vasoconstricción y menor sudoración); además, incrementar la producción de calor, intensificando la actividad muscular. Conclusión. La termorregulación es liderada por el hipotálamo, quien regula aumento y disminución de la temperatura respondiendo a las necesidades del organismo para llegar a la homeostasis y compensación, enfrentando las alteraciones de la temperatura ambiental