A Pharmacotherapeutic Approaches for Managing Labour Pain Using Synthetic Drugs and Natural Therapies

The birth of a child is a critical and potentially traumatic experience for women, entailing multiple physiological and psychosocial changes. The psychological effects of childbirth pain can have both immediate and long-term effects on the mother's health and her bond with her child. Many studies investigated the different ranges of synthetic drugs available for pain control in labour, inclusive of neuraxial analgesics, inhaled analgesics, and various opioids. The inadequate efficacy and unfavourable side effects of these synthetic drugs prevent appropriate pharmacotherapy, resulting in a quest for natural therapies for reducing labour pain. Herbal therapies (aromatherapy) using several essential oils obtained from various natural plants are another alternative that calms and manages the mind and body through aromatic compounds that have neurological and physiological effects. The review discussed the safety profile of various synthetic drugs with their dosage information and also deliberated on the mechanism and safety profile of various natural plants that are used in aromatherapy. The review also briefly highlighted the other non-pharmacological miscellaneous techniques such as TENS, hypnosis, immersion in water, acupuncture, massage, and different other tactics that aim to assist women in coping with pain in labour.

Perinatal outcomes after therapeutic rest in the latent phase of labor: A cohort study

INTRODUCTION

Therapeutic rest refers to the usage of medication to relieve pain in women in the latent phase of labor. Very few data are available to evaluate the safety and effect of its use. The objectives of this study were to compare perinatal and labor outcomes in women who were seeking hospital care during the latent phase of labor and who were treated either with or without therapeutic rest.

MATERIAL AND METHODS

Retrospective cohort study with inclusion of nulliparous singleton pregnant women in the latent phase of labor presenting at the labor ward at Aarhus University Hospital, Denmark from May 13, 2018 to June 1, 2021. We identified two groups: women who were treated with therapeutic rest and women who were not. The primary outcomes were neonatal admission and neonatal resuscitation. Secondary outcomes included use of cardiotocography during labor, nonreactive fetal heart rate, meconium-stained amniotic fluid, pediatric delivery room assistance, umbilical cord arterial pH and standard base excess, Apgar score at 5 minutes, interventions during labor and mode of delivery.

RESULTS

In our sample of 800 women in the latent phase of labor, 414 women (52%) were treated with therapeutic rest and 386 women (48%) were not. The most frequently used (n = 206) medication for therapeutic rest was a combination of paracetamol, triazolam and codeine. We found no significant difference in neonatal admission (9.2% vs 6.5%, adjusted odds ratio [aOR] 1.2, 95% confidence interval [CI] 0.4-3.1) or neonatal resuscitation (2.4% vs 3.1%, aOR 0.7, 95% CI 0.1-4.0) between women treated with or without therapeutic rest. There were no differences between the two groups in other perinatal adverse outcomes, interventions during labor or mode of delivery.

CONCLUSIONS

This study found no significant association between therapeutic rest and neonatal admission or resuscitation. Our findings indicate that therapeutic rest is a safe method for managing the latent phase of labor concerning neonatal health and does not increase the risk of labor complications.

Comparison of Pain Scale, Hemodynamics, and Side Effects of Percutaneous and Intravenous Fentanyl in Post Sectio Caesaria Patients at Bunda Hospital

This is novel research about comparison pain scale, hemodynamics, and side effects of percutaneous and intravenous fentanyl in post sectio cesarean patients. Sectio cesarean is a method of delivering a fetus through an incision in the abdominal wall (laparotomy) and the uterus wall. This method induces pain in the incision, so patients feel complicated or afraid to mobilize. Fentanyl is one of the opioid analgesics, which is the main choice in section caesarian surgery because safe for breastfeeding, is more potent than morphine, and acts as balanced anesthesia—comparing the use of percutaneous fentanyl with intravenous fentanyl with pain scale parameters, hemodynamics, and side effects in sectio caesarian patients at Bunda Mother and Child Hospital Jakarta. Before conducting this research, an observational study first makes an ethical approval. Data were taken prospectively and collected simultaneously to compare percutaneous and intravenous fentanyl performed on post sectio cesarean patients with the physical status of the American Society of Anesthesiologists (ASA) I–II at Bunda Mother and Child Hospital Jakarta from September to November 2020. Comparative data observed were pain scale parameters, hemodynamics, and side effects after percutaneous fentanyl therapy or intravenous fentanyl therapy. Data were processed using SPSS 22 version and Microsoft Excell 2016. In conclusion, intravenous fentanyl is more effective in reducing pain scale and has more minor side effects than percutaneous fentanyl. There is no significant difference in hemodynamic parameters (p-value >0.05).

Pharmacologic and non-pharmacologic labor pain management techniques in a resource-limited setting: A systematic review

Background

Despite improvement in pain management programs, labor pain is mostly ignored especially in low and middle-income countries.

Methods

The aim of this study is to establish a clear clinical working guideline for labor pain management in resource limited settings. This systematic review is conducted in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline 2020. After formulating clear criteria for the evidences to be included an appropriate method of searching was conducted by using the Pub Med, Google scholar and Cochrane library using the following MeSH terms: (‘Parenteral opioids’ AND′ Labor pain’, ‘Labor’ AND ‘Pain management, ‘Non-pharmacologic methods ‘AND ‘Labor pain’, ‘Labor pain management AND massage therapy). The study quality of literatures was categorized based on WHO 2011 level of evidence and degree of recommendation. Final conclusions and recommendations are done with the analysis of risk and benefits of alternative management strategies for non-regional techniques of labor pain management. The study is registered with research registry unique identifying number (UIN) of 1267 “https://www.researchregistry.com/browse-the-registry#registryofsystematicreviewsmeta-analyses/.” and the study is moderate based on AMSTAR 2 quality assessment criteria/https://amstar.ca/Amstar_Checklist.php.

Discussion

Combined forms of Non-pharmacologic and selected low dose pharmacologic approaches of labor pain management, provides significant benefits to women and their infants. During provision of labor analgesia complications may happen and the service provider should involve in the management of those complications.

Conclusion

This study has a paramount importance to practice the most reliable, available and cost effective method of labor analgesia.

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Appropriate history and physical examinations are crucial to avoid contraindicated medications in labor pain managment.

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Combined non-pharmacologic methods with a lower dose of indicated drugs provides significant advantages for both mothers and their infants.

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Using available and cost effective labor pain managment with minimal complications has paramount importance in resource limited setting.

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During provision of labor analgesia service provider should aware of complications to intervene at theright time.

The association between intrapartum opioid fentanyl and early breastfeeding: A prospective observational study

INTRODUCTION

Intrapartum opioids in labor may interfere with the early breastfeeding phase and cause breastfeeding difficulties. This study examines the effects of intrapartum fentanyl given intravenously (IV) or through epidural analgesia (EDA) on early breastfeeding.

MATERIAL AND METHODS

This is a prospective observational study conducted in a regional maternity unit. We included 1101 healthy mothers of term singleton babies in vertex presentation born between 2016 and 2018 (468 nulliparous and 633 multiparous). The main data were collected prospectively, and additional data were retrieved from hospital records. The main outcome measures were exclusive breastfeeding at discharge, spontaneous suckling, and breastfeeding problems after birth. We assessed the outcomes in four groups categorized by intrapartum opioid exposure: none, IV fentanyl, EDA fentanyl and IV+EDA fentanyl. We also analyzed the dose-response relation of fentanyl administered by epidural or IV and early breastfeeding. Ultimately, we dichotomized the IV fentanyl group into two groups (≤200 µg and >200 µg) to further study the effect on early breastfeeding.

RESULTS

The odds of non-exclusive breastfeeding were doubled with EDA fentanyl (odds ratio [OR] 2.45, 95% CI 1.34-4.48, p = 0.004) and four times higher with IV+EDA fentanyl (OR 4.20, 95% CI 2.49-7.09, p < 0.001) compared with no opioid exposure. Spontaneous suckling was negatively associated with intrapartum fentanyl use (p < 0.001) irrespective of mode of administration. When the IV fentanyl doses exceeded 200 µg compared with less than 200 µg, we found a reduction in exclusive breastfeeding (81% vs. 89%; p = 0.014) and spontaneous suckling (68% vs. 83%; p < 0.001) and an increase in breastfeeding problems (41% vs. 27%; p = 0.004).

CONCLUSIONS

Fentanyl in labor is associated with breastfeeding difficulties. However, IV fentanyl in low doses (≤200 µg) seems to affect breastfeeding less than EDA fentanyl and is therefore a viable alternative when labor analgesia is needed. This could be most relevant for multiparous women, where a shorter labor is expected. More research is needed to determine the optimal dose and route of administration of fentanyl for labor analgesia.

Association of Self-Administered Nitrous Oxide for Labor Analgesia With Maternal and Neonatal Process and Outcome Measures

OBJECTIVE

To describe patterns of use of self-administered nitrous oxide (N₂O) during labor and to determine if maternal and neonatal process and outcome measures differ for women who use N₂O compared to women who do not use N₂O.

DESIGN

Retrospective, full-census, observational cohort.

SETTING

An upper midwestern U.S., urban, 75-bed quaternary perinatal center with more than 5,000 annual births.

PARTICIPANTS

The participants included two groups of women: 400 who used N₂O during labor and a comparison group of 6,733 who met N₂O eligibility but did not use N₂O.

METHODS

We used descriptive statistics to examine patterns of use of N₂O during labor between January 2015 and March 2017. We examined associations of N₂O with process (length of first and second stages of labor, time from hospital admission to birth, time from birth to hospital discharge, and total length of stay) and outcome measures (shoulder dystocia, instrumentation, vaginal lacerations, Apgar scores at 5 minutes, nursery disposition) using multivariate linear, logistic, and ordinal regression models.

RESULTS

Three percent (12/400) of women who used N₂O discontinued because of side effects. Among participants with vaginal births who used N₂O, 17.6% (62/352) used N₂O as the only form of pain medication during labor. We found no significant differences in maternal and neonatal outcome measures between the two groups. Among the process measures examined, we found a mean 2-hour-longer time from admission to birth and total length of stay in the N₂O group (p < .05) compared to the non-N₂O group.

CONCLUSION

Most participants who used N₂O (290/352, 82.3%) transitioned to other pain modalities during labor. Maternal and neonatal process and outcome measures were comparable relative to other pain management modalities, with the exception of longer time durations for two measures.

Opioid effect on the autonomic nervous system in a fetal sheep model

PURPOSE

Opioid use during labour can interfere with cardiotocography patterns. Heart rate variability indirectly reflects a fluctuation in the autonomic nervous system and can be monitored through time and spectral analyses. This experimental study aimed to evaluate the impact of nalbuphine administration on the gasometric, cardiovascular, and autonomic nervous system responses in fetal sheep.

METHODS

This was an experimental study on chronically instrumented sheep fetuses (surgery at 128 ± 2 days of gestational age, term = 145 days). The model was based on a maternal intravenous bolus injection of nalbuphine, a semisynthetic opioid used as an analgesic during delivery. Fetal gasometric parameters (pH, pO₂, pCO₂, and lactates), hemodynamic parameters (fetal heart rate and mean arterial pressure), and autonomic nervous system tone (short-term and long-term variation, low-frequency domain, high-frequency domain, and fetal stress index) were recorded. Data obtained at 30-60 min after nalbuphine injection were compared to those recorded at baseline.

RESULTS

Eleven experiments were performed. Fetal heart rate, mean arterial pressure, and activities at low and high frequencies were stable after injection. Short-term variation decreased at T30 min (P = 0.02), and long-term variation decreased at T60 min (P = 0.02). Fetal stress index gradually increased and reached significance at T60 min (P = 0.02). Fetal gasometric parameters and lactate levels remained stable.

CONCLUSION

Maternal nalbuphine use during labour may lead to fetal heart changes that are caused by the effect of opioid on the autonomic nervous system; these fluctuations do not reflect acidosis.

[Normal childbirth: physiologic labor support and medical procedures. Guidelines of the French National Authority for Health (HAS) with the collaboration of the French College of Gynaecologists and Obstetricians (CNGOF) and the French College of Midwives (CNSF) - Mother's wellbeing and regional or systemic analgesia for labor]

INTRODUCTION

These guidelines deal with the parturient wellbeing in terms of hydration and regional and systemic pain management during labour.

METHOD

Guidelines were established based on literature analysis and experts consensus.

RESULTS

Clear liquids consumption is permitted all along labor and postpartum, without volume limitation, in patients at low risk of general anesthesia (grade B). The consumption of solid foods is not recommended during the active stage of labor (consensus agreement). It is recommended to promote on regional analgesia to prevent inhalation (grade A). Pain relief using regional analgesia is a part of normal childbirth. It is recommended to provide regional analgesia to parturient who wish these technics. Regional analgesia is the safest and most effective analgesic method for the mother (grade A) and the child (grade B). It is recommended to inform women on the analgesic technics, to respect their choice and consider the right for a parturient to change her strategy in obstetrical circumstances or in cases of untractable pain (consensus agreement). It is recommended to perform a "low-dose" regional analgesia that respects the experience of childbirth (grade A) and maintain it with a patient controlled epidural analgesia technics (grade A). There is no minimum cervical dilation to allow epidural analgesia (grade A). In cases of rapid labor or after delivery for revision, spinal or combined spinal epidural can be used (grade C). Epidural has not to be ended before birth (consensus agreement). Blood pressure and fetal heart rate must be monitored every 3minutes after induction and/or each 10mL bolus then hourly (consensus agreement). Systematic and preventive fluid loading is not needed if only due to regional analgesia (grade B). Deambulation or postures are allowed in the absence of motor block and must be traced and do not alter the distribution of the regional analgesia (grade C). The postures of childbirth do not alter regional analgesia spread (NP2). There is no effect low dose regional analgesia on the duration of obstetric labor, nor the rate of instrumental births or caesarean section (NP1). Systematic use of oxytocin due to epidural analgesia is neither useful nor recommended (AE). Regional analgesia has no side effect on the fetus or newborn (NP1). If regional analgesia is contraindicated or during the waiting time, alternatives analgesic drugs (entonox, nalbuphine and tramadol or pudendal block) can be used but their analgesic efficiency remains mediocre to moderate and they are associated with adverse maternal and especially neonatal side effects (NP2). Remifentanil, ketamine and volatile anesthetics are excluded from these recommendations.

CONCLUSION

The present guidelines were established to update wellbeing of normal parturient during normal labor: hydration is recommended and low dose patient-controlled regional (epidural and spinal) analgesia is the most effective and safest analgesic method.

Subcutaneous fentanyl for labour analgesia: a retrospective case note review

BACKGROUND

In 2017, a South Australia Perinatal Practice Guideline was introduced state-wide for the use of subcutaneous fentanyl for labour analgesia as a replacement for intramuscular pethidine. We retrospectively reviewed the implementation of this practice change in our institution.

METHODS

A retrospective review of maternal and neonatal case notes for the first 100 women administered subcutaneous fentanyl in labour at a single tertiary referral centre for maternity care, between February and June 2017.

RESULTS

Of the 102 women administered subcutaneous fentanyl, the majority (55%) were primipara, with an average maternal age of 29 years and body mass index of 27 kg/m². The median total fentanyl dose administered was 200 µg and the average time from last dose to birth was 3 h. The majority of women (70%) did not require additional rescue labour analgesia and 80% had a spontaneous vaginal birth. All neonates had a 5-min Apgar score >7. The median Apgar score at 1 and 5 min was 9. No neonate had an arterial cord blood pH <7.1. The mean arterial and venous cord blood pH was 7.3. The average time for neonates to establish breathing was 1 min and the median postnatal length of stay was two days.

CONCLUSIONS

Subcutaneous fentanyl for labour analgesia appears effective and has a low incidence of adverse events.

Medication used in Denmark in the latent phase of labor - Do we know what we are doing?

OBJECTIVE

To describe the various combinations of medication used in Denmark in the latent phase of labor (i.e. for therapeutic rest) and to estimate the frequency of use.

METHODS

An informal e-mail survey based on personal information from Danish midwives or staff obstetricians. The main outcome measures were type and dosage of medications used individually or in combination ("cocktail") for therapeutic rest in Danish delivery wards during the latent phase of labor and also the frequency of their use.

RESULTS

All twenty-one delivery wards in Denmark participated in the survey. The types and dosages of medication varied substantially. Two delivery wards used prescriptions on morphine with no other medication for therapeutic rest. The remaining 19/21 delivery wards (90%) used a standard "cocktail" with two to four different types of medications; 19/21 wards (90%) used a mild analgesic (paracetamol), 17/21 (81%) used anxiolytics/hypnotics, and 14/21 (64%) wards used a strong analgesic (opioid) in their basic cocktail. Ten delivery wards (48%) combined an opioid, a sedative, and paracetamol in their basic cocktail. Between 7% and 21% of all pregnant women were given a cocktail.

CONCLUSION

In a small country, we found considerable national variation in the medication or combinations of medication used in the latent phase of labor, and polypharmacy was standard in the majority of the delivery wards.

Comparison of nalbuphine, ondansetron and placebo for the prevention of shivering after spinal anaesthesia for urgent caesarean delivery: a randomised double-blind controlled clinical trial

BACKGROUND

Shivering is a common complication of caesarean delivery with neuraxial anaesthesia. The effective prevention and treatment of shivering, especially before delivery, is important and difficult. We tested the hypothesis that prophylactic nalbuphine and ondansetron can prevent post-spinal anaesthesia shivering in parturients undergoing urgent caesarean delivery.

METHODS

Sixty parturients scheduled for urgent caesarean delivery before spinal anaesthesia were selected and divided randomly into three groups. After peripheral venous catheterisation, parturients were given intravenous nalbuphine 0.08 mg/kg (group N), ondansetron 8 mg (group O), or normal saline (group C).

RESULTS

The incidence of shivering and of severe (grade ≥3) shivering was significantly lower in group N (15% and 15%, respectively) than in group C (80% and 65%) before delivery (P <0.001 and P=0.003); and significantly less shivering was observed in group N than in group C in the first 30 min after anaesthesia (P=0.001). Up to 60 min after anaesthesia, the incidence of grade ≥3 shivering remained lowest in group N (P=0.003). According to the data during the period from anaesthesia until delivery, the number needed-to-treat for nalbuphine was 1.54 (95%CI 1.13 to 2.41). No significant differences were found between groups O and N or groups O and C at any time. The incidence of dizziness in group N was significantly higher than that of groups O or C (P=0.009).

CONCLUSION

Nalbuphine 0.08 mg/kg can prevent post-spinal anaesthesia shivering in parturients undergoing urgent caesarean delivery but causes transient dizziness, while ondansetron 8 mg had no significant effect.

Polymorphisms associated with fentanyl pharmacokinetics, pharmacodynamics and adverse effects

Fentanyl is an agonist of the μ-opioid receptor commonly used in the treatment of moderate-severe pain. In order to study whether pharmacogenetics explains some of the variability in the response to fentanyl, several genes related to fentanyl receptors, transporters and metabolic enzymes have been analysed. Thirty-five healthy volunteers (19 men and 16 women) receiving a single 300 μg oral dose of fentanyl were genotyped for 9 polymorphisms in cytochrome P450 (CYP) enzymes (CYP3A4 and CYP3A5), ATP-binding cassette subfamily B member 1 (ABCB1), opioid receptor mu 1 (OPRM1), catechol-O-methyltransferase (COMT) and adrenoceptor beta 2 (ADRB2) by real-time PCR. Fentanyl concentrations were measured by ultra-performance liquid chromatography combined with tandem mass spectrometry (UPLC-MS/MS). Fentanyl pharmacokinetics is affected by sex. Carriers of the CYP3A4*22 allele, which is known to reduce the mRNA expression, showed higher area under the concentration-time curve (AUC) and lower clearance (Cl) values. Although this finding might be of importance, its validity needs to be confirmed in other similar settings. Furthermore, carriers of the ABCB1 C1236T T/T genotype presented a lower AUC and higher Cl, as well as lower half-life (T_1/2 ). As volunteers were blocked with naltrexone, the effect of fentanyl on pharmacodynamics might be biased; however, we could observe that fentanyl had a hypotensive effect. Moreover, ADRB2 C523A A allele carriers showed a tendency towards reducing systolic blood pressure. Likewise, OPRM1 and COMT minor allele variants were risk factors for the development of somnolence. CYP3A5*3, ABCB1 C3435T and ABCB1 G2677T/A were not associated with fentanyl's pharmacokinetics, pharmacodynamics and safety profile.

Nitrous oxide for labor analgesia

Inhaled nitrous oxide (N2O) has been used worldwide for over 100 years as labor analgesia but has not gained widespread use in the United States. Nitrous oxide provides a noninvasive option for laboring women. This article outlines its efficacy and safety as an analgesic compared with epidural and IV pain medications.

The Effect of Epidural Analgesia Alone and in Association With Other Variables on the Risk of Cesarean Section

Introduction:

Epidural analgesia (EA) is the most widespread pharmacologic method of labor pain relief. There remains disagreement, however, regarding its adverse effects. The objective of this study was to determine the effect of EA administration on the risk of cesarean delivery and its causes (e.g., stalled labor, risk of loss of fetal well-being, among others) and the degree to which this effect may be modulated by mother-, newborn-, and labor-related variables.

Method:

A retrospective cohort observational study was conducted including all deliveries in a Spanish public hospital between March 2010 and March 2013 ( N = 2,450; EA = 562, non-EA = 1,888).

Results:

Risk of a cesarean section was significantly increased by EA administration (odds ratio [ OR] = 2.673; p < .0001). The percentage of cesarean deliveries due to the risk of loss of fetal well-being was significantly higher in the EA (47.8%) versus non-EA group (27.5%; OR = 1.739; p = 0.0012,). The EA-associated risk of cesarean section was not significantly modified as a function of maternal age or parity, fetal position, newborn weight, weeks of gestation, or sedation administration alone. However, these variables in combination may increase the risk. We present multivariate models for each group that account for these variables, allowing for estimation of the risk of a cesarean delivery if EA is administered.

Conclusion:

EA is associated with an increased risk of cesarean delivery. Other variables in combination (maternal age or parity, fetal position, newborn weight, weeks of gestation, or sedation administration) may increase this risk.

Does meperidine analgesia affect the incidence of obstetric lacerations at vaginal delivery?

PURPOSE

To study whether meperidine analgesia affects the incidence of obstetric lacerations at normal vaginal deliveries.

MATERIALS AND METHODS

A retrospective cohort study of all women with term vertex singleton pregnancies, who underwent normal vaginal deliveries, in a single tertiary hospital, between 2011 and 2015, was performed. The incidence of various obstetric lacerations was compared between deliveries with meperidine analgesia and deliveries with no analgesia. Deliveries with epidural analgesia and instrumental deliveries were excluded. An intravenous infusion of 75 mg of meperidine was administered together with 25 mg of promethazine. A multivariate logistic regression analysis was performed to assess the association between meperidine analgesia and obstetric lacerations, after controlling for confounders.

RESULTS

Overall, 5227 (91.8%) deliveries with no analgesia and 466 (8.1%) deliveries with meperidine analgesia were included. Meperidine analgesia was associated with a decreased risk of first- and second-degree perineal lacerations (adjusted OR = 0.63, 95% CI = 0.49-0.81), and a decreased risk of any suturing (adjusted OR = 0.73, 95% CI = 0.59-0.91), after controlling for confounders. Meperidine analgesia did not affect the risk of severe perineal lacerations or episiotomies.

CONCLUSION

Meperidine analgesia may have a protective effect against first- and second-degree perineal lacerations.

Intermittent auscultation (IA) of fetal heart rate in labour for fetal well-being

BACKGROUND

The goal of fetal monitoring in labour is the early detection of a hypoxic baby. There are a variety of tools and methods available for intermittent auscultation (IA) of the fetal heart rate (FHR). Low- and middle-income countries usually have only access to a Pinard/Laënnec or the use of a hand-held Doppler device. Currently, there is no robust evidence to guide clinical practice on the most effective IA tool to use, timing intervals and length of listening to the fetal heart for women during established labour.

OBJECTIVES

To evaluate the effectiveness of different tools for IA of the fetal heart rate during labour including frequency and duration of auscultation.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (19 September 2016), contacted experts and searched reference lists of retrieved articles.

SELECTION CRITERIA

All published and unpublished randomised controlled trials (RCTs) or cluster-RCTs comparing different tools and methods used for intermittent fetal auscultation during labour for fetal and maternal well-being. Quasi-RCTs, and cross-over designs were not eligible for inclusion.

DATA COLLECTION AND ANALYSIS

All review authors independently assessed eligibility, extracted data and assessed risk of bias for each trial. Data were checked for accuracy.

MAIN RESULTS

We included three studies (6241 women and 6241 babies), but only two studies are included in the meta-analyses (3242 women and 3242 babies). Both were judged as high risk for performance bias due to the inability to blind the participants and healthcare providers to the interventions. Evidence was graded as moderate to very low quality; the main reasons for downgrading were study design limitations and imprecision of effect estimates. Intermittent Electronic Fetal Monitoring (EFM) using Cardiotocography (CTG) with routine Pinard (one trial)There was no clear difference between groups in low Apgar scores at five minutes (reported as < six at five minutes after birth) (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.24 to 1.83, 633 babies, very low-quality evidence). There were no clear differences for perinatal mortality (RR 0.88, 95% CI 0.34 to 2.25; 633 infants, very low-quality evidence). Neonatal seizures were reduced in the EFM group (RR 0.05, 95% CI 0.00 to 0.89; 633 infants, very low-quality evidence). Other important infant outcomes were not reported: mortality or serious morbidity (composite outcome), cerebral palsy or neurosensory disability. For maternal outcomes, women allocated to intermittent electronic fetal monitoring (EFM) (CTG) had higher rates of caesarean section for fetal distress (RR 2.92, 95% CI 1.78 to 4.80, 633 women, moderate-quality evidence) compared with women allocated to routine Pinard. There was no clear difference between groups in instrumental vaginal births (RR 1.46, 95% CI 0.86 to 2.49, low-quality evidence). Other outcomes were not reported (maternal mortality, instrumental vaginal birth for fetal distress and or acidosis, analgesia in labour, mobility or restriction during labour, and postnatal depression). Doppler ultrasonography with routine Pinard (two trials)There was no clear difference between groups in Apgar scores < seven at five minutes after birth (reported as < six in one of the trials) (average RR 0.76, 95% CI 0.20 to 2.87; two trials, 2598 babies, I2 = 72%, very low-quality evidence); there was high heterogeneity for this outcome. There was no clear difference between groups for perinatal mortality (RR 0.69, 95% CI 0.09 to 5.40; 2597 infants, two studies, very low-quality evidence), or neonatal seizures (RR 0.05, 95% CI 0.00 to 0.91; 627 infants, one study, very low-quality evidence). Other important infant outcomes were not reported (cord blood acidosis, composite of mortality and serious morbidity, cerebral palsy, neurosensory disability). Only one study reported maternal outcomes. Women allocated to Doppler ultrasonography had higher rates of caesarean section for fetal distress compared with those allocated to routine Pinard (RR 2.71, 95% CI 1.64 to 4.48, 627 women, moderate-quality evidence). There was no clear difference in instrumental vaginal births between groups (RR 1.35, 95% CI 0.78 to 2.32, 627 women, low-quality evidence). Other maternal outcomes were not reported. Intensive Pinard versus routine Pinard (one trial)One trial compared intensive Pinard (a research midwife following the protocol in a one-to-one care situation) with routine Pinard (as per protocol but midwife may be caring for more than one woman in labour). There was no clear difference between groups in low Apgar score (reported as < six this trial) (RR 0.90, 95% CI 0.35 to 2.31, 625 babies, very low-quality evidence). There were also no clear differences identified for perinatal mortality (RR 0.56, 95% CI 0.19 to 1.67; 625 infants, very low-quality evidence), or neonatal seizures (RR 0.68, 95% CI 0.24 to 1.88, 625 infants, very low-quality evidence)). Other infant outcomes were not reported. For maternal outcomes, there were no clear differences between groups for caesarean section or instrumental delivery (RR 0.70, 95% CI 0.35 to 1.38, and RR 1.21, 95% CI 0.69 to 2.11, respectively, 625 women, both low-quality evidence)) Other outcomes were not reported.

AUTHORS' CONCLUSIONS

Using a hand-held (battery and wind-up) Doppler and intermittent CTG with an abdominal transducer without paper tracing for IA in labour was associated with an increase in caesarean sections due to fetal distress. There was no clear difference in neonatal outcomes (low Apgar scores at five minutes after birth, neonatal seizures or perinatal mortality). Long-term outcomes for the baby (including neurodevelopmental disability and cerebral palsy) were not reported. The quality of the evidence was assessed as moderate to very low and several important outcomes were not reported which means that uncertainty remains regarding the use of IA of FHR in labour.As intermittent CTG and Doppler were associated with higher rates of caesarean sections compared with routine Pinard monitoring, women, health practitioners and policy makers need to consider these results in the absence of evidence of short- and long-term benefits for the mother or baby.Large high-quality randomised trials, particularly in low-income settings, are needed. Trials should assess both short- and long-term health outcomes, comparing different monitoring tools and timing for IA.

Butorphanol use in laboring patients with preeclampsia or chronic hypertension

OBJECTIVE

The American College of Obstetricians and Gynecologists (ACOG) recommends against the use of butorphanol in patients diagnosed with preeclampsia or chronic hypertension secondary to a theoretical concern that the drug will further elevate blood pressures. No past study has examined the drug's potential to elevate blood pressures in laboring patients.

METHODS

In this retrospective cohort study all chronic hypertensive and preeclamptic patients who underwent an induction of labor and delivered a viable, singleton pregnancy between the dates of 1/1/2013 and 12/31/2014 at a single academic hospital were included.

RESULTS

The use of butorphanol in chronically hypertensive patients during labor was not associated with the presence of severe range blood pressures during labor (OR=0.92 95% CI: (0.04-19.34) P=0.96). In preeclamptic patients there was similarly no change in the frequency of severe range blood pressures with the use of the drug (OR=0.59 95% CI: (0.19-1.83) P=0.36).

CONCLUSION

In laboring patients with chronic hypertension or preeclampsia butorphanol is not associated with severe range blood pressures, and therefore it is a reasonable option for providing pain relief in these populations.

Effects of μ-opioid receptor agonists in assays of acute pain-stimulated and pain-depressed behavior in male rats: role of μ-agonist efficacy and noxious stimulus intensity

Pain is associated with stimulation of some behaviors and depression of others, and μ-opioid receptor agonists are among the most widely used analgesics. This study used parallel assays of pain-stimulated and pain-depressed behavior in male Sprague-Dawley rats to compare antinociception profiles for six μ-agonists that varied in efficacy at μ-opioid receptors (from highest to lowest: methadone, fentanyl, morphine, hydrocodone, buprenorphine, and nalbuphine). Intraperitoneal injection of diluted lactic acid served as an acute noxious stimulus to either stimulate stretching or depress operant responding maintained by electrical stimulation in an intracranial self-stimulation (ICSS). All μ-agonists blocked both stimulation of stretching and depression of ICSS produced by 1.8% lactic acid. The high-efficacy agonists methadone and fentanyl were more potent at blocking acid-induced depression of ICSS than acid-stimulated stretching, whereas lower-efficacy agonists displayed similar potency across assays. All μ-agonists except morphine also facilitated ICSS in the absence of the noxious stimulus at doses similar to those that blocked acid-induced depression of ICSS. The potency of the low-efficacy μ-agonist nalbuphine, but not the high-efficacy μ-agonist methadone, to block acid-induced depression of ICSS was significantly reduced by increasing the intensity of the noxious stimulus to 5.6% acid. These results demonstrate sensitivity of acid-induced depression of ICSS to a range of clinically effective μ-opioid analgesics and reveal distinctions between opioids based on efficacy at the μ-receptor. These results also support the use of parallel assays of pain-stimulated and -depressed behaviors to evaluate analgesic efficacy of candidate drugs.

Pharmacogenetics of chronic pain management

OBJECTIVE

The experience of chronic pain is one of the commonest reasons individuals seek medical attention, making the management of chronic pain a major issue in clinical practice. Drug metabolism and responses are affected by many factors, with genetic variations offering only a partial explanation of an individual's response. There is a paucity of evidence for the benefits of pharmacogenetic testing in the context of pain management.

DESIGN AND METHODS

We reviewed the literature between 2000 and 2013, and references cited therein, using various keywords related to pain management, pharmacology and pharmacogenetics.

RESULTS

Opioids continue to be the mainstay of chronic pain management. Several non-opioid based therapies, such as treatment with cannabinoids, gene therapy and epigenetic-based approaches are now available for these patients. Adjuvant therapies with antidepressants, benzodiazepines or anticonvulsants can also be useful in managing pain. Currently, laboratory monitoring of pain management patients, if performed, is largely through urine drug measurements.

CONCLUSIONS

Drug half-life calculations can be used as functional markers of the cumulative effect of pharmacogenetics and drug-drug interactions. Assessment of half-life and therapeutic effects may be more useful than genetic testing in preventing adverse drug reactions to pain medications, while ensuring effective analgesia. Definitive, mass spectrometry-based methods, capable of measuring parent drug and metabolite levels, are the most useful assays for this purpose. Urine drug measurements do not necessarily correlate with serum drug concentrations or therapeutic effects. Therefore, they are limited in their use in monitoring efficacy and toxicity.

Pharmacogenomics in the nursing literature: an integrative review

BACKGROUND

Pharmacogenomics is a rapidly growing component of personalized health care, and nurses must be competent to deliver genomic-focused nursing care.

METHODS

We conducted an integrative review of pharmacogenomics in the nursing literature. A comprehensive search of the nursing literature was conducted using the key words pharmacogenomics and pharmacogenetics. A total of 47 unique articles were included.

RESULTS

Articles represented mainly narrative reviews, with limited discussions of the implications for nursing practice, education, or research. As such, they provide limited direction for advancing either clinical practice or scientific inquiry.

CONCLUSIONS

This review serves as a call to action for more systematic and empirical publications addressing pharmacogenomics in nursing practice, education, and research. Nurses must be involved in and contribute to interdisciplinary conversations and burgeoning clinical practice initiatives related to pharmacogenomics.

Intravenous oxycodone for pain relief in the first stage of labour--maternal pharmacokinetics and neonatal exposure

Physiological changes during pregnancy may change pharmacokinetics of compounds. Oxycodone is an increasingly used opioid agonist in acute pain management but its pharmacokinetics in labouring women has not been established. We studied the maternal pharmacokinetics and neonatal exposure of intravenous oxycodone for pain relief in the first stage of labour. The study was prospective, open-labelled and with a control group. After informed consent, 15 nulliparous parturients and newborns, and newborns in a control group were studied. In the study group, oxycodone boluses of 1 mg i.v., up to a cumulative dose of 5 mg, was administered when labour pain score was 5/10 or higher. As the control group, 30 other newborns after uncomplicated deliveries with no systemic opioids were assessed for the neonatal outcome. In the study group, maternal pharmacokinetics of oxycodone was measured from plasma concentrations during labour, and neonatal exposure was assessed from umbilical plasma samples using population pharmacokinetic methods. Maternal plasma oxycodone concentration decreased with a median half-life of 2.6 hr (range, 1.8-2.8). Oxycodone concentrations in the umbilical plasma 2.7 μg/l (0.3-14.5) were similar as in maternal plasma 2.4 (0.1-14.8) μg/l at the time of birth. No severe or unexpected adverse effects were noted. To conclude, firstly, maternal elimination half-life of i.v. oxycodone was significantly shorter than that reported in non-pregnant women, and secondly, maternal plasma oxycodone at the birth correlated well with neonatal umbilical concentrations and may, thus, be used as an estimate of neonatal exposure.

Pain relief in labor: a survey of awareness, attitude, and practice of health care providers in Zaria, Nigeria

Background:

The purpose of this study was to assess the attitudes of maternal health care providers to pain relief during labor in Zaria, Nigeria.

Methods:

This was a multicenter, collaborative, cross-sectional pilot study of provider perspectives concerning pain relief during labor. A structured, self-administered, questionnaire was completed by 95 consenting maternal health care providers at three high-volume facilities in Zaria, an ancient northern Nigerian city. Descriptive statistics was performed on the data.

Results:

Most respondents (94.8%) agreed that pain relief is needed during labor. Only 2.1% of respondents were undecided about the provision of pain relief during labor and 3.2% were of the opinion that pain relief was not necessary during labor. Most respondents (93.7%) had attended a woman in labor in the 4 weeks preceding the survey. Of these, 56.8% had counseled a parturient in labor. Most of the counseling (42.1%) took place during labor. Less than half of the respondents (48.4%) had administered pain relief in labor in the preceding 4 weeks and systemic opioids was the most commonly form of pain relief. Among the respondents who did not offer pain relief agents in labor, the majority (54.5%) had no reason for not offering it. Unavailability of methods, inability to afford the cost of pain relief, lack of knowledge and skills, as well as lack of essential equipment to provide the procedure were also given by respondents as reasons for not offering pain relief.

Conclusion:

Even though maternal health care providers in this environment have a positive attitude to pain relief in labor, most women go through labor without the benefit of analgesia. There exists a gap between provider attitudes to pain relief in labor and practice of the same, with many providers having no genuine reason(s) for not offering pain relief to their clients during labor. Providers need to align their practice to their attitudes, and need to be helped to do this through training as well as enhancing their ability to think critically about their practice.