Average and time-specific maternal prenatal inflammatory biomarkers and the risk of labor epidural associated fever

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.

Intrapartum fever complicated with maternal bacteremia: prevalence, bacteriology, and risk factors

PURPOSE

To assess the prevalence, microbial profile, and clinical risk factors of maternal bacteremia associated with intrapartum fever (IPF).

METHODS

A retrospective cohort study, in a single tertiary university-affiliated medical center between 2012 and 2018. Demographic and labor characteristics of women, who delivered at term (37+0/7-41+6/7) and developed bacteremia following IPF were compared to a control group of women with IPF but without bacteremia.

RESULTS

During the study period there were 86,590 deliveries in our center. Of them, 2074 women (2.4%) were diagnosed with IPF, of them, for 2052 women (98.93%) the blood maternal cultures were available. In 26 patients (1.25%) maternal bacteremia was diagnosed. A lower rate of epidural anesthesia (84.6% vs 95.9%, p = 0.02) and a higher rate of antibiotics prophylaxis treatment prior to the onset of fever (30.8%.vs 12.1%, p = 0.006) were observed in patients who developed maternal bacteremia in comparison to those who have not. Maternal hyperpyrexia developed after initiation of antibiotics or without epidural anesthesia remained significantly associated with maternal bacteremia after applying a multivariate analysis, (Odds Ratio 3.14 95% CI 1.27-7.14, p = 0.009; 4.76 95% CI 1.35-12.5, p = 0.006; respectively).

CONCLUSION

Maternal fever developing after initiation of antibiotics or without epidural is associated with maternal bacteremia.

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.

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)