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

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.

Predictive value of neutrophil-to-lymphocyte ratio on admission for intrapartum maternal fever in parturients undergoing epidural analgesia: A retrospective cohort study using propensity score-matched analysis

OBJECTIVE

To identify the predictive value of the neutrophil-to-lymphocyte ratio (NLR) on admission for intrapartum maternal fever in parturients undergoing epidural analgesia (EA).

METHODS

In this retrospective cohort study, propensity score matching (PSM) was applied to address covariates. Univariate and multivariate regression analyses were implemented in sequence to find out the factors influencing intrapartum fever. The receiver operating characteristics curve was applied to determine the area under the curve (AUC) of NLR for intrapartum fever.

RESULTS

NLR and duration of EA were independent risk factors for intrapartum fever. The AUC of the combined indicator (NLR + duration of EA) was higher than that of NLR (AUC = 0.583, 95% confidence interval [CI] 0.53-0.64) and duration of EA (AUC = 0.702, 95% CI 0.66-0.75), reaching 0.715 (95% CI 0.67-0.76; p < 0.001). NLR increased predictive performance for intrapartum fever when added to the duration of EA (net reclassification index 0.076, p = 0.022; integrated discrimination improvement 0.020, p = 0.002).

CONCLUSION

NLR has limited predictive power for intrapartum fever. The combination of NLR and duration of epidural analgesia may be considered a promising predictor for intrapartum maternal fever in parturients undergoing epidural analgesia.

SYNOPSIS

The neutrophil-to-lymphocyte ratio is an accessible predictor for the early identification of parturients at risk of intrapartum fever.

Effect of different concentrations of sufentanil combined with ropivacaine on epidural fever during labor: A single-center retrospective study

Labor epidural analgesia (LEA) is associated with increased maternal body temperature; however, the responsible mechanism is unknown. Recent studies suggest that changes in EA affect the incidence of fever and that epidural sufentanil supplementation enhances analgesia and reduces the amount of local anesthetic. The aim of this study was to evaluate the effect of different concentrations of sufentanil combined with ropivacaine on intrapartum fever during delivery. We performed a retrospective study comparing maternal fever rates in patients receiving labor analgesia between December 2018 and January 2019. Each patient receiving different concentrations of sufentanil in their EA received either proposal H (0.08% ropivacaine + 0.4 µg/mL sufentanil) or proposal L (0.08% ropivacaine + 0.2 µg/mL sufentanil), with the same nulliparous status. The primary outcome of this study was the incidence of intrapartum maternal fever, which was defined as any temperature ≥ 38°C during labor using Fisher exact test. Secondary outcome measures included visual analog scale (VAS) pain scores, birth events, and neonatal outcomes. We observed a perinatal fever incidence rate of 11.7% in the group receiving proposal L, while the incidence rate was 19.8% in the group receiving proposal H (P = .001). Five hours after administration, the average body temperature of the puerpera decreased significantly in the proposal L group compared with proposal H group. In addition, treatment with 0.2 µg/mL sufentanil provided satisfactory pain relief during labor, shortened the first stage of labor and total labor time, reduced oxytocin use, and had no significant adverse effects on neonatal outcomes. EA may increase the risk of intrapartum epidural-associated fever. Compared with the 0.4 µg/mL sufentanil group, the 0.2 µg/mL sufentanil group can provide better analgesia and improve maternal fever. These retrospective results highlighted the importance of prospective and mechanistic studies of maternal fever associated with intraspinal analgesia.

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.

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.

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.

Effects of neuraxial labor analgesia on intrapartum maternal fever in full-term pregnancy and its influence on birth outcomes

Introduction

This study aimed to explore the relationship between neuraxial labor analgesia and intrapartum fever and to demonstrate the influence of maternal fever on perinatal outcomes within 6 weeks after birth.

Methods

This was a secondary analysis of a multicenter prospective cohort study that enrolled women with single- and full-term cephalic pregnancy in northern China. Intrapartum maternal fever was defined as the highest axillary temperature during labor ≥37.5°C. Data on baseline characteristics, maternal variables, and neonatal outcomes were all collected. The association between neuraxial labor analgesia and intrapartum maternal fever was analyzed with logistic regression models, and the cutoff point was identified by the receiver operating characteristic curve.

Results

Of 577 parturients, 74 (12.8%) developed intrapartum fever. Neuraxial analgesia was associated with an increased risk of maternal intrapartum fever with or without adjusting for confounding factors (adjusted OR = 2.68; 95% CI: 1.32-5.47; p = 0.007). Further analysis showed that neuraxial analgesia of <5 h did not increase the risk of intrapartum fever compared with no analgesia (OR = 1.52; 95% CI: 0.63-3.64; p = 0.35), and longer neuraxial labor analgesia time (over 5 h) significantly increased the risk of fever (OR = 3.38; 95% CI: 1.63-7.01; p = 0.001). Parturients with intrapartum fever suffered more maternal adverse outcomes compared with those without fever (p < 0.001). Neonates of women with intrapartum fever had slightly higher rates of composite adverse neonatal outcomes compared with those without fever; however, the difference was not statistically significant (p = 0.098).

Conclusion

In women with low-risk pregnancies, a longer time of neuraxial labor analgesia was associated with an increased risk of intrapartum maternal fever. Intrapartum fever was related to adverse maternal outcomes but did not significantly affect neonatal outcomes within 6 weeks after delivery.

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.

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.