The association between epidural labor analgesia and maternal fever

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.

Modern labor epidural analgesia: implications for labor outcomes and maternal-fetal health

Epidural analgesia is an important means of pain control during labor throughout the world. Over its historic development, it has been implicated in several undesirable outcomes, including prolongation of labor and increased need for operative delivery. These effects have emerged in some retrospective and observational studies, but such methods of investigation are highly prone to bias and are particularly ill-suited for the study of labor analgesia. In high-quality studies, including Cochrane reviews and meta-analyses, epidural analgesia has been suggested to extend the first stage of labor by 30 minutes and the second stage by 15 minutes, when compared with alternative forms of analgesia. Although this may be a reproducible effect, it may be argued that it is clinically negligible. With respect to mode of delivery, similar high-quality studies have consistently shown no increased risk of cesarean delivery associated with epidural analgesia. Some forms of epidural analgesia were associated with higher risk of assisted vaginal delivery, but the use of newer modalities has been shown to abolish this effect. Specific advancements have centered on reducing total anesthetic consumption, given that local anesthetic-induced motor block is theorized to interfere with maternal expulsive efforts in the second stage of labor. These measures include the use of low-concentration local anesthetic solutions equivalent to ≤0.1% bupivacaine, shown in meta-analyses to lead to no higher risk of assisted vaginal delivery relative to nonepidural analgesia. Additional advancements in the maintenance of analgesia include programmed intermittent epidural bolus and patient-controlled epidural analgesia, the combination of which has been shown to reduce the risk of assisted vaginal delivery, also likely mediated by reduction in local anesthetic dose. These techniques have gained popularity in the past two decades, such that studies published since 2005 show no higher risk of assisted vaginal delivery with epidural than with opioid analgesia (as reported in a Cochrane review). Labor epidural analgesia has implications for maternal and fetal health perinatally. It is known to result in transient maternal hypotension (particularly with initiation), which may progress to the level of necessitating fluid or vasopressor therapy. This is not clearly associated with any adverse outcomes. There is also a consistently higher incidence of fever in parturients receiving neuraxial anesthesia, likely of noninfectious origin, which has similarly not been associated with adverse neonatal outcomes. Finally, neonates of parturients who receive epidural analgesia have been shown to have no worse Apgar scores and more favorable acid-base status than their counterparts. These observations should serve to reassure providers that modern labor analgesia, as currently understood, is not consistently associated with any significant adverse outcomes for the parturient or fetus. In this review, we describe variations of modern labor epidural analgesia, conduct an in-depth review of current literature on its use, and explore the most up-to-date evidence on its implications for the progression and outcomes of labor, including the pertinent maternal and fetal side effects.

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.

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.

The effect of delivery ball and warm shower on the childbirth experience of nulliparous women: a randomized controlled clinical trial

INTRODUCTION

Childbirth is a unique experience that affects women's life. Midwives can play an effective role in creating positive birth experiences for women using non-pharmacological and supportive methods. Accordingly, this study aims to determine the effect of delivery balls and warm showers on childbirth experiences of primiparous women.

METHODS

This clinical trial was conducted on primiparous pregnant women who referred to the Motazedi Hospital in Kermanshah, Iran. Sampling was done from eligible individuals by a continuous method, and pregnant women were assigned to the three groups of delivery balls plus warm showers or A (n = 35), delivery balls or B (n = 35), and control or C (n = 35). The use of the ball at the dilation of 4 cm was similar in the two groups of A and B, but the first group used a warm shower at the dilatation of 7 cm as well. The control group also received routine delivery care. Besides, demographic information forms consisting of the pregnancy history and some information about the mother and her infant were completed. Additionally, childbirth experience questionnaires (CEQ) were completed by the women two hours after childbirth. The analysis of intervention effects was performed as per-protocol analysis.

RESULTS

There was a statistically significant difference in the mean score of the childbirth experience between the two groups of A and C (p = 0.001) after the intervention as well as between the groups of B and C (p = 0.001).

CONCLUSION

The use of delivery balls and warm showers was effective in creating a positive childbirth experience. To create a positive childbirth experience in mothers, the use of both interventions (delivery balls and warm showers) is recommended.

TRIAL REGISTRATION

TCTR 20200408002 . Prospectively registered on March 21, 2020.

Maternal and fetal hypothermia: more preventive compliance is required for a mother and her fetus while undergoing cesarean delivery; a quality improvement review

OBJECTIVE

Cesarean delivery is common, involves two patients, has numerous multi-disciplinary health care providers involved in the delivery management, but has variable levels of anesthesia and health services implementation for decreasing maternal hypothermia and the maternal and neonatal morbidity (and mortality). Limited implementation for either of the ERAS-CD or the ERAC guidelines, for inadvertent or preventive maternal hypothermia, is likely to be occurring on labor delivery floors. This Quality Improvement (QI) review focuses on cesarean delivery and maternal hypothermia.

METHODS

This quality and safety initiative used SQUIRE 2.0 methodology and concurrent PubMed searches to identify systematic review, meta-analysis, topic directed studies, additional published cohorts in the topic area not included in SR/MA, limited case reports that had specific clinical outcomes related to maternal hypothermia and fetal effects.

RESULTS

Two quality and safety improvement guidelines have defined the hypothermia activity element differently, with ERAS-CD recommending to prevent hypothermia, while ERAC recommending to maintain normothermia. The peer-reviewed literature indicates that the knowledge associated with surgical hypothermia outcome is known but it is not implemented for maternal cesarean delivery care. Increased maternal-effect recognition, surveillance, triage, and evidenced-based protocol management is required for the maternal - neonatal dyad undergoing cesarean delivery for the clinical reduction/prevention of neonatal hypothermia that has proven evidence-based maternal morbidity and neonatal morbidity/mortality.

CONCLUSION

TEAM-based anesthesia, obstetrical, neonatology-pediatrics and nursing research collaboration is required through quality-safety-ERAS-ERAC directed processes. Healthcare system recognition and financial support is required for maternal-fetal-neonatal hypothermia prevention protocols implementation.

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.

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.

Degree of intrapartum fever and associated factors: Three group analysis of no fever, borderline and overt fever

AIM

Previous studies analyzing intrapartum fever by dichotomization of fever just above 38.0°C or not may lead to overlook clinical significance of borderline fever. We aimed to investigate the maternal baseline and intrapartum characteristics, neonatal outcomes, and inflammatory placental pathology in relation to the degree of intrapartum fever by three group analysis.

METHODS

We performed a retrospective analysis of consecutive singleton deliveries between 37^0/7 to 41^0/7 weeks divided into three groups based on the peak body temperature during labor: No fever (< 37.5°C), borderline fever (≥ 37.5°C and < 38.0°C), and overt fever (≥ 38.0°C). Maternal and intrapartum characteristics, neonatal outcomes, and inflammatory placental pathology were compared by trend analysis, intergroup difference analysis, and multivariable analysis.

RESULTS

The degree of intrapartum fever was significantly associated with younger maternal age, nulliparity, longer duration of rupture of membrane, and epidural analgesia (p < 0.001). And the incidence of neonatal proven sepsis and mortality were not significantly different among the groups. The degree of intrapartum fever was associated with the stage of acute chorioamnionitis and funisitis (p < 0.001). Multivariate analysis revealed that the association with epidural analgesia was stronger in borderline fever than overt fever (adjusted odds ratio [95% confidence interval], borderline fever = 18.487 [11.447-29.857]; overt fever = 11.068 [4.874-25.133]) after controlling for maternal age, parity, induction or augmentation, duration of ROM, birth weight, and meconium staining.

CONCLUSION

Our data support that both epidural analgesia and inflammation of the placenta may contribute to the development of intrapartum fever at term.

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.

The value of amniotic fluid analysis in patients with suspected clinical chorioamnionitis

Objective To assess the value of incorporating amniotic fluid (AF) analysis in the management of patients with clinical chorioamnionitis. Methods This was a retrospective cohort study of all women carrying a singleton fetus and managed at our center between 2000 and 2009. We included only those women suspected of chorioamnionitis based on one or more of the following: (1) uterine tenderness, (2) maternal fever, (3) maternal and/or fetal tachycardia and (4) purulent discharge. The management was deemed to be justified if (1) pregnancy was terminated <24 weeks and histology confirmed chorioamnionitis; (2) delivery was performed expeditiously after initial assessment and histology confirmed chorioamnionitis; (3) delivery was delayed for 2-7 days and the patient completed a course of antenatal steroids before 34 weeks; and (4) delivery was delayed ≥7 days and histology was not indicative of chorioamnionitis, or delivery occurred after 37 weeks. Univariate and logistic regression analyses were used as appropriate. Results Of the 77 women with suspected chorioamnionitis, AF analysis was performed in 43 (55.8%) cases, and the management was justified in 63 (81.8%) cases based on the aforementioned criteria. Stepwise regression analysis confirmed AF analysis as a predictor of justified management. The rates of composite morbidity, neonatal sepsis, neonatal death and admissions to neonatal intensive care unit were lower in the justified management group. Conclusion Incorporation of AF analysis into clinical assessment does improve the management of suspected chorioamnionitis.

A Review of the Impact of Obstetric Anesthesia on Maternal and Neonatal Outcomes

Obstetric anesthesia has evolved over the course of its history to encompass comprehensive aspects of maternal care, ranging from cesarean delivery anesthesia and labor analgesia to maternal resuscitation and patient safety. Anesthesiologists are concerned with maternal and neonatal outcomes, and with preventing and managing complications that may present during childbirth. The current review will focus on recent advances in obstetric anesthesia, including labor anesthesia and analgesia, cesarean delivery anesthesia and analgesia, the effects of maternal anesthesia on breastfeeding and fever, and maternal safety. The impact of these advances on maternal and neonatal outcomes is discussed. Past and future progress in this field will continue to have significant implications on the health of women and children.

Epidural Labor Analgesia and Maternal Fever

Women receiving an epidural for labor analgesia are at increased risk for intrapartum fever. This relationship has been supported by observational, before and after, and randomized controlled trials. The etiology is not well understood but is likely a result of noninfectious inflammation as studies have found women with fever have higher levels of inflammatory markers. Maternal pyrexia may change obstetric management and women are more likely to receive antibiotics or undergo cesarean delivery. Maternal pyrexia is associated with adverse neonatal outcomes. With these consequences, understanding and preventing maternal fever is imperative.

Fetal and maternal temperatures during labor and delivery: a prospective descriptive study

OBJECTIVE

The objective of this study is to study the fetal scalp temperature (FST) and maternal axillary temperature (MAT) during vaginal delivery relative to progression of labor, uterine contractions (UC) and epidural analgesia (EDA), and to construct normal temperature reference ranges related to stage of labor.

MATERIAL AND METHODS

Temperatures were recorded continuously in labor of 132 women with a bi-metal temperature sensor attached to the axilla (MAT) and a similar sensor mounted in a scalp electrode (FST). The temperature data were stored electronically and analyzed offline at cervical dilatations of 2-3, 5, 7-8, and 10 cm, and at full retraction. The FST was read before, at increasing, at peak, at decreasing, and after UC. The MAT and FST curves were compared with mixed-effect models statistics for repeated measurements. A two-tailed p <.05 was considered significant.

RESULTS

The FST did not vary during UC (p = .24). Both FST and MAT increased linearly by progression of labor (both p < .001). The increases in temperatures were greater with EDA than without (p < .001).

CONCLUSIONS

During UC, the FST showed no alteration. Both FST and MAT increased significantly by progression of labor, and significantly more in the presence of EDA. The presented normal temperature reference ranges can be used for future research.

A state-wide assessment of the association between epidural analgesia, maternal fever and neonatal antibiotics in Colorado, 2007-2012

OBJECTIVE

To determine if an association exists between epidural analgesia, maternal fever and neonatal antibiotic exposure in a state-wide birth cohort.

DESIGN, SETTING AND PARTICIPANTS

We performed a retrospective cohort study of the population-based Colorado Department of Public Health and Environment birth certificate database. Data included all reported births in the state of Colorado between 2007 and 2012. Live, non-preterm, vaginal, singleton, in-hospital births were included in analysis.

EXPOSURE

Maternal epidural analgesia and maternal fever.

MAIN OUTCOMES MEASURES

Neonatal antibiotic treatment for suspected sepsis. A stratified analysis was conducted to evaluate whether epidural use was an effect modifier of the association between maternal fever and neonatal antibiotic treatment.

RESULTS

The final cohort included 261 457 births. 2.2% of women who received an epidural had a fever, as compared with 0.4% of women who did not receive an epidural (OR: 5.4; 95% CI 4.9 to 6.0), and neonates born to women who received an epidural had 1.26 times increased odds of antibiotic treatment (95% CI 1.1 to 1.4). Stratification by epidural use did not alter the association between maternal fever and neonatal antibiotic treatment.

CONCLUSIONS

Colorado providers treat neonates born to mothers with maternal fever without respect to whether the mother had an epidural. Further research into improved criteria for neonatal sepsis evaluation that accounts for the contribution of maternal epidural fever should be developed to decrease unnecessary neonatal antibiotic exposure.

Systematic Review of Hydrotherapy Research: Does a Warm Bath in Labor Promote Normal Physiologic Childbirth?

Health sciences research was systematically reviewed to assess randomized controlled trials of standard care versus immersion hydrotherapy in labor before conventional childbirth. Seven studies of 2615 women were included. Six trials examined hydrotherapy in midwifery care and found an effect of pain relief; of these, 2 examined analgesia and found reduced use among women who bathed in labor. One study each found that hydrotherapy reduced maternal anxiety and fetal malpresentation, increased maternal satisfaction with movement and privacy, and resulted in cervical dilation progress equivalent to standard labor augmentation practices. Studies examined more than 30 fetal and neonatal outcomes, and no benefit or harm of hydrotherapy was identified. Two trials had anomalous findings of increased newborn resuscitation or nursery admission after hydrotherapy, which were not supported by additional results in the same or other studies. Review findings demonstrate that intrapartum immersion hydrotherapy is a helpful and benign practice. Hydrotherapy facilitates physiologic childbirth and may increase satisfaction with care. Maternity care providers are recommended to include hydrotherapy among routine labor pain management options and consider immersion to promote progress of normal or protracted labor, particularly among women with preferences to avoid obstetric medications and procedures.

Risk Factors for Neonatal Arterial Ischemic Stroke: The Importance of the Intrapartum Period

OBJECTIVE

To investigate risk factors for neonatal arterial ischemic stroke (NAIS), and compare them with those present in term controls and infants with hypoxic-ischemic encephalopathy (HIE).

STUDY DESIGN

Antepartum and intrapartum data were collected at presentation from 79 infants with NAIS and compared with 239 controls and 405 infants with HIE. The relationships between risk factors and NAIS were explored using univariable and multivariable regression.

RESULTS

Compared with controls, infants with NAIS more frequently had a family history of seizures/neurologic diseases, primiparous mothers, and male sex. Mothers of infants with NAIS experienced more intrapartum complications: prolonged rupture of membranes (21% vs 2%), fever (14% vs 3%), thick meconium (25% vs 7%), prolonged second stage (31% vs 13%), tight nuchal cord (15% vs 6%), and abnorm8al cardiotocography (67% vs 21%). Male sex (OR 2.8), family history of seizures (OR 6.5) or neurologic diseases (OR 4.9), and ≥1 (OR 5.8) and ≥2 (OR 21.8) intrapartum complications were independently associated with NAIS. Infants with NAIS and HIE experienced similar rates though different patterns of intrapartum complications. Maternal fever, prolonged rupture of membranes, prolonged second stage, tight nuchal cord, and failed ventouse delivery were more common in NAIS; thick meconium, sentinel events, and shoulder dystocia were more frequent in HIE. Abnormal cardiotocography occurred in 67% of NAIS and 77.5% of infants with HIE. One infant with NAIS and no infant with HIE was delivered by elective cesarean (10% of controls).

CONCLUSIONS

NAIS is multifactorial in origin and shares risk factors in common with HIE. Intrapartum events may play a more significant role in the pathogenesis of NAIS than previously recognized.

Clinical chorioamnionitis at term IV: the maternal plasma cytokine profile

INTRODUCTION

Fever is a major criterion for clinical chorioamnionitis; yet, many patients with intrapartum fever do not have demonstrable intra-amniotic infection. Some cytokines, such as interleukin (IL)-1, IL-6, interferon-gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α), can induce a fever. The objective of this study was to determine whether maternal plasma concentrations of cytokines could be of value in the identification of patients with the diagnosis of clinical chorioamnionitis at term who have microbial-associated intra-amniotic inflammation.

METHODS

A retrospective cross-sectional study was conducted, including patients with clinical chorioamnionitis at term (n=41; cases) and women in spontaneous labor at term without clinical chorioamnionitis (n=77; controls). Women with clinical chorioamnionitis were classified into three groups according to the results of amniotic fluid culture, broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry (PCR/ESI-MS), and amniotic fluid IL-6 concentration: 1) no intra-amniotic inflammation; 2) intra-amniotic inflammation without detectable microorganisms; or 3) microbial-associated intra-amniotic inflammation. The maternal plasma concentrations of 29 cytokines were determined with sensitive and specific V-PLEX immunoassays. Nonparametric statistical methods were used for analysis, adjusting for a false discovery rate of 5%.

RESULTS

1) The maternal plasma concentrations of pyrogenic cytokines (IL-1β, IL-2, IL-6, IFN-γ, and TNF-α) were significantly higher in patients with clinical chorioamnionitis at term than in those with spontaneous term labor without clinical chorioamnionitis; 2) the maternal plasma concentrations of cytokines were not significantly different among the three subgroups of patients with clinical chorioamnionitis (intra-amniotic inflammation with and without detectable bacteria and those without intra-amniotic inflammation); and 3) among women with the diagnosis of clinical chorioamnionitis, but without evidence of intra-amniotic inflammation, the maternal plasma concentrations of pyrogenic cytokines were significantly higher than in patients with spontaneous labor at term. These observations suggest that a fever can be mediated by increased circulating concentrations of these cytokines, despite the absence of a local intra-amniotic inflammatory response.

CONCLUSIONS

1) The maternal plasma concentrations of pyrogenic cytokines (e.g. IL-1β, IL-2, IL-6, IFN-γ, and TNF-α) are higher in patients with intra-partum fever and the diagnosis of clinical chorioamnionitis at term than in those in spontaneous labor at term without a fever; and 2) maternal plasma cytokine concentrations have limited value in the identification of patients with bacteria in the amniotic cavity. Accurate assessment of the presence of intra-amniotic infection requires amniotic fluid analysis.

Clinical chorioamnionitis at term III: how well do clinical criteria perform in the identification of proven intra-amniotic infection?

OBJECTIVE

The diagnosis of clinical chorioamnionitis is based on a combination of signs [fever, maternal or fetal tachycardia, foul-smelling amniotic fluid (AF), uterine tenderness and maternal leukocytosis]. Bacterial infections within the amniotic cavity are considered the most frequent cause of clinical chorioamnionitis and an indication for antibiotic administration to reduce maternal and neonatal morbidity. Recent studies show that only 54% of patients with the diagnosis of clinical chorioamnionitis at term have bacteria in the AF and evidence of intra-amniotic inflammation. The objective of this study was to examine the performance of the clinical criteria for the diagnosis of chorioamnionitis to identify patients with microbial-associated intra-amniotic inflammation (also termed intra-amniotic infection).

MATERIALS AND METHODS

This retrospective cross-sectional study included 45 patients with the diagnosis of clinical chorioamnionitis at term, whose AF underwent analysis for: 1) the presence of microorganisms using both cultivation and molecular biologic techniques [polymerase chain reaction (PCR) with broad primers], and 2) interleukin (IL)-6 concentrations by enzyme-linked immunosorbent assay. The diagnostic performance (sensitivity, specificity, accuracy, and likelihood ratios) of each clinical sign and their combination to identify clinical chorioamnionitis were determined using microbial-associated intra-amniotic inflammation [presence of microorganisms in the AF using cultivation or molecular techniques and elevated AF IL-6 concentrations (≥2.6 ng/mL)] as the gold standard.

RESULTS

The accuracy of each clinical sign for the identification of microbial-associated intra-amniotic inflammation (intra-amniotic infection) ranged between 46.7% and 57.8%. The combination of fever with three or more clinical criteria did not substantially improve diagnostic accuracy.

CONCLUSION

In the presence of a fever during labor at term, signs used to diagnose clinical chorioamnionitis do not accurately identify the patient with proven intra-amniotic infection (i.e., those with microorganisms detected by culture or molecular microbiologic techniques and an associated intra-amniotic inflammatory response).

Comparison Between the Use of Ropivacaine Alone and Ropivacaine With Sufentanil in Epidural Labor Analgesia

To compare the analgesic efficacy and safety of the sole local anesthetic ropivacaine with the combination of both local anesthetic ropivacaine and opioidergic analgesic sufentanil given epidurally on the labor pain control.After institutional review board approval and patient consent, a total of 500 nulliparas requesting epidural labor analgesia were enrolled and 481 eventually were randomized into 2 groups: a sole local anesthetic group (ropivacaine 0.125%) and a combination of local anesthetic and opioidergic analgesic group (0.125% ropivacaine + 0.3 μg/mL sufentanil). After the test dose, a 10-mL epidural analgesic solution was given in a single bolus, followed by intermittent bolus injection of 10 to 15 mL of the solution. The primary outcome was the analgesic efficacy measured using Numerical Rating Scale (NRS) of pain. Other maternal and infant variables were evaluated as secondary outcomes.A total of 346 participants completed the study. The median NRS pain score during the 1st stage of labor was significantly lower in the combination group 2.2 (interquartile range [IQR]: 1.8-2.7) comparing to the sole local analgesic group 2.4 (IQR: 2.0-2.8) (P < 0.0001). No significant difference was observed in NRS pain score prior epidural analgesia and during the 2nd stage of labor. Patients in both groups rated same satisfaction of analgesia. Patients in the sole local analgesic group experienced fewer side effects than those in the combination group (37.7% vs 47.2%, P = 0.082). The individual analgesia-related cost in the sole local analgesic group was less ($5.7 ± 2.06) than that in the combination group ($9.76 ± 3.54) (P < 0.0001). The incidence of 1-minute Apgar ≤ 7 was lower in the sole local analgesic group 2 (1.2%) than the combination group 10 (5.5%) (P = 0.038). No difference was found between other secondary outcomes.The sole local anesthetic ropivacaine produces a comparable labor analgesic effect as the combination of both local anesthetic ropivacaine and opioidergic analgesic sufentanil at different stages of labor (ΔNRS = 0.2) but the former has less side effects, lower cost, and less incidence of lower 1-minute Apgar scoring. These results imply the necessity of a systematic reevaluation of epidural labor analgesia with sole local anesthetics against combination regimens of local anesthetics and other opioids.