Alternatives to neuraxial analgesia for labor

[Spinal Analgesia - Cleverly Used for Vaginal Delivery]

Neuroaxial procedures are among the most effective ways of relieving pain during childbirth. Especially in the late phase of vaginal delivery, surprising moments, instrumental methods or special maneuvers require quick and sufficient analgesia. This refers to situations with a sudden, often unexpected and particularly pronounced intensity of pain. Here the advantages of spinal analgesia over the gold standard of obstetric analgesia, catheter epidural analgesia, can be used. Spinal analgesia is characterized by a fast onset of pain relief, a profound blockage and simple technical feasibility and, like other neuroaxial procedures, is comparatively uncomplicated in pregnant women. However, it is only effective if the delivery situation is well assessed. There is no possibility of repetition without re-puncture, so that limited duration of action is a significant disadvantage. Applied drugs correspond to those described for combined spinal and epidural analgesia, such as a mixture of low-dose bupivacaine and sufentanil, and can be adapted to local conditions. In the future, longer acting substances could overcome the main limitation (temporary effect) of spinal analgesia and suitable adjuvants could further increase the attractiveness of the procedure.

Pain management during labor and vaginal birth

Neuraxial analgesia provides excellent pain relief in labor. Optimizing initiation and maintenance of neuraxial labor analgesia requires different strategies. Combined spinal-epidurals or dural puncture epidurals may offer advantages over traditional epidurals. Ultrasound is useful in certain patients. Maintenance of analgesia is best achieved with a background regimen (either programmed intermittent boluses or a continuous epidural infusion) supplemented with patient-controlled epidural analgesia and using dilute local anesthetics combined with opioids such as fentanyl. Nitrous oxide and systemic opioids are also used for pain relief. Nitrous oxide may improve satisfaction despite variable effects on pain. Systemic opioids can be administered by healthcare providers or using patient-controlled analgesia. Appropriate choice of drug should take into account the stage and progression of labor, local safety protocols, and maternal and fetal/neonatal side effects. Pain in labor is complex, and women should fully participate in the decision-making process before any one modality is selected.

Neuraxial labor analgesia: a literature review

The use of analgesia techniques for labor has become increasingly frequent, with neuraxial techniques being the most commonly used and most effective. Labor pain entails a number of physiological consequences that may be negative for the mother and fetus, and therefore must be treated. This literature review was performed through a search in the PubMed database, from July to November 2016, and included articles in English or Portuguese, published between 2011 and 2016 or anteriorly, if relevant to the topic. The techniques were divided into the following topics: induction (epidural, combined epidural-spinal, continuous spinal, and epidural with dural puncture) and maintenance of analgesia (continuous epidural infusion, patient-controlled epidural analgesia, and intermittent epidural bolus). Epidural analgesia does not alter the incidence of cesarean sections or fetal prognosis, and maternal request is a sufficient indication for its initiation. The combined technique has the advantage of a faster onset of analgesia; however, patients are subject to a higher incidence of pruritus resulting from the intrathecal administration of opioids. Patient-controlled analgesia seems to be an excellent technique, reducing the consumption of local anesthetics, the number of anesthesiologist interventions, and increasing maternal satisfaction.

Should maternal anesthesia delay breastfeeding? A systematic review of the literature

Introduction

The importance and benefits of breastfeeding for the babies and mothers are well established and documented in the literature. However, it is frequent that lactating mothers need to undergo general or spinal anesthesia and, due to the lack of information, many of them interrupt breastfeeding after anesthesia. There are limited data available regarding anesthetics transfer to breast milk. This review aims to develop some considerations and recommendations based on available literature.

Methods

A systematic search of the literature was conducted by using the following health science databases: Embase, Lilacs, Pubmed, Scopus, and Web of Science. The latest literature search was performed on April 6^th, 2018. Additional literature search was made via the World Health Organization's website. We used the following terms for the search strategy: “Anesthesia” and “Breastfeeding”, and their derivatives.

Results

In this research, 599 registers were found, and 549 had been excluded by different reasons. Fifty manuscripts have been included, with different designs of studies: prospective trials, retrospective observational studies, reviews, case reports, randomized clinical trials, case–control, and website access. Small concentrations of the most anesthetic agents, are transferred to the breast milk; however, their administration seem to be safe for lactating mothers when administered as a single dose during anesthesia and this should not contraindicate the breastfeeding. On the other hand, high-doses, continuous or repeated administration of drugs increase the risk of adverse effects on neonates, and should be avoided. Few drugs, such as diazepam and meperidine, produce adverse effects on breastfed babies even in single doses. Dexmedetomidine seems to be safe if breastfeeding starts 24 h after discontinuation of the drug.

Conclusions

Most of the anesthetic drugs are safe for nursing mothers and offer low risk to the breastfed neonates when administered in single-dose. However, high-dose and repeated administration of drugs significantly increase the risk of adverse effects on neonates. Moreover, diazepam and meperidine should be avoided in nursing women. Finally, anesthesiologists and pediatricians should consider individual risk/benefit, with special attention to premature neonates or babies with concurrent diseases since they are more susceptible to adverse effects.

[Neuraxial labor analgesia: a literature review]

The use of analgesia techniques for labor has become increasingly frequent, with neuraxial techniques being the most commonly used and most effective. Labor pain entails a number of physiological consequences that may be negative for the mother and fetus, and therefore must be treated. This literature review was performed through a search in the PubMed database, from July to November 2016, and included articles in English or Portuguese, published between 2011 and 2016 or anteriorly, if relevant to the topic. The techniques were divided into the following topics: induction (epidural, combined epidural-spinal, continuous spinal, and epidural with dural puncture) and maintenance of analgesia (continuous epidural infusion, patient-controlled epidural analgesia, and intermittent epidural bolus). Epidural analgesia does not alter the incidence of cesarean sections or fetal prognosis, and maternal request is a sufficient indication for its initiation. The combined technique has the advantage of a faster onset of analgesia; however, patients are subject to a higher incidence of pruritus resulting from the intrathecal administration of opioids. Patient-controlled analgesia seems to be an excellent technique, reducing the consumption of local anesthetics, the number of anesthesiologist interventions, and increasing maternal satisfaction.

[Should maternal anesthesia delay breastfeeding? A systematic review of the literature]

INTRODUCTION

The importance and benefits of breastfeeding for the babies and mothers are well established and documented in the literature. However, it is frequent that lactating mothers need to undergo general or spinal anesthesia and, due to the lack of information, many of them interrupt breastfeeding after anesthesia. There are limited data available regarding anesthetics transfer to breast milk. This review aims to develop some considerations and recommendations based on available literature.

METHODS

A systematic search of the literature was conducted by using the following health science databases: Embase, Lilacs, Pubmed, Scopus, and Web of Science. The latest literature search was performed on April 6^th, 2018. Additional literature search was made via the World Health Organization's website. We used the following terms for the search strategy: "Anesthesia" and "Breastfeeding", and their derivatives.

RESULTS

In this research, 599 registers were found, and 549 had been excluded by different reasons. Fifty manuscripts have been included, with different designs of studies: prospective trials, retrospective observational studies, reviews, case reports, randomized clinical trials, case-control, and website access. Small concentrations of the most anesthetic agents, are transferred to the breast milk; however, their administration seem to be safe for lactating mothers when administered as a single dose during anesthesia and this should not contraindicate the breastfeeding. On the other hand, high-doses, continuous or repeated administration of drugs increase the risk of adverse effects on neonates, and should be avoided. Few drugs, such as diazepam and meperidine, produce adverse effects on breastfed babies even in single doses. Dexmedetomidine seems to be safe if breastfeeding starts 24h after discontinuation of the drug.

CONCLUSIONS

Most of the anesthetic drugs are safe for nursing mothers and offer low risk to the breastfed neonates when administered in single-dose. However, high-dose and repeated administration of drugs significantly increase the risk of adverse effects on neonates. Moreover, diazepam and meperidine should be avoided in nursing women. Finally, anesthesiologists and pediatricians should consider individual risk/benefit, with special attention to premature neonates or babies with concurrent diseases since they are more susceptible to adverse effects.

Non-Neuraxial Labor Analgesia: Options

Although it is the most effective method to treat labor pain, neuraxial analgesia may be undesired, contraindicated, unsuccessful, or unavailable. Providing safe choices for labor pain relief is a central goal of health care providers alike. Consequently, knowledge of the efficacy, clinical implementation, and side effects of various non-neuraxial strategies is needed to provide appropriate options for laboring patients. In addition to nonpharmacologic alternatives, inhaled nitrous oxide and systemic opioids represent two broad classes of non-neuraxial pharmacologic labor analgesia most commonly available. This review summarizes the current published literature for these non-neuraxial labor analgesic options.

Effectiveness of injecting lower dose subcutaneous sterile water versus saline to relief labor back pain: Randomized controlled trial

INTRODUCTION

The aim of this study was to investigate the effect of a lower dose subcutaneous sterile water injection technique versus subcutaneous saline injection, on the relief of low-back pain for women during childbirth, and to explore the lasting effects of pain relief after administration (followed at 15, 30, 45, 90 and 120 minutes).

METHODS

A prospective randomized controlled single-blinded study was conducted, with trial registration (NCT02813330). Women received one-time injections (sterile water or saline) and the effectiveness was observed at 15, 30, 45, 90 and 120 minutes after the intervention.

RESULTS

The intervention group had statistically significant pain reduction. Assessment of subsequent pain, followed at 30, 45, 90 and 120 minutes, reflected an increasing change with a statistically significant difference. The intervention group had more burning sensations than the control group with a statistically significant difference.

CONCLUSIONS

The modified technique of double injections of subcutaneous ‘water/ saline’ resulted in significant relief of low-back pain during childbirth.

Clinical comparative study on Nitrous Oxide inhalation versus intravenous propofol and Midazolam sedation in Transnasal Gastroscopy

Objective:

To investigate the Clinical practice value of nitrous oxide inhalation and intravenous propofol and midazolam sedation in transnasal gastroscopy.

Method:

From December 2012 to April 2014, two hundred patients receiving painless transnasal gastroscopy on a voluntary basis were selected in Endoscopy center, The First People’s Hospital of GuiYang. Patients were divided into two groups: Group-1 consisted of one hundred patients sedated by nitrous oxide inhalation and Group-2 consisted of one hundred patients sedated by intravenous propofol and midazolam. Patients were then examined by transnasal gastroscopy. Patient blood pressure, heart rate, pulse rate and oxygen saturation before, during and after gastroscopy were recorded for both groups. The duration of the gastroscopy and the time of awakening were also recorded. After examination, the patients were asked to assess the level of discomfort experiences during the gastroscopy procedure.

Results:

All patients successfully underwent the transnasal gastroscopy. There were 57 males and 43 females in the nitrous oxide inhalation group with an average age of 43.11±8.27 years. The average duration of examination and time of awaking in the nitrous oxide inhalation group was of 152.7±9.80 secs and 50±7.89 secs respectively. For the intravenous propofol and midazolam sedation group, there were 53 males and 47 females with an average age of 41.26±7.98 years. The average duration of examination and time of awaking in the intravenous propofol and midazolam sedation group was of 149.07±10.25 seconds and 390±20.89^# seconds respectively. The two groups showed no significant difference in the duration of examination. There was no difference in the age or sex. The former had a less significant impact on heart rate, oxygen saturation and blood pressure, while the intravenous propofol and midazolam sedation decreased blood pressure dramatically and this effect persisted after examination.

Conclusion:

Nitrous oxide inhalation has higher safety and tolerance with a brighter application prospect for transnasal gastroscopy.

Pain Management in Obstetrics

Critical care clinicians may be called on to care for a laboring woman. Comprehension of the anatomic changes associated with pregnancy, and labor and birth, is essential. A working knowledge of the current options for pain management in labor, both pharmacologic and nonpharmacologic, is necessary to facilitate patient-centered care. Pharmacologic options include intravenous or intramuscular agents, inhalational agents, and neuraxial anesthesia. Each modality has contraindications, risks, and benefits that must be considered when choosing the most appropriate method.

Nitrous oxide labor analgesia and pain relief memory in breastfeeding women

OBJECTIVE

The use of labor pain relief medications is a controversial issue that has engendered heated discussions among health care professionals about safety, interference with birthing, and breastfeeding.

METHODS

This is a case-control study with 62 puerperae treated with nitrous oxide and 124 control women (ratio 1:2), matched for age, gestational age, parity, delivery route, labor augmentation, and spinal regional analgesia. We tested anhedonia, anxiety, and depression symptoms at hospital discharge by The Edinburgh Postnatal Depression Scale (EPDS), and the intensity of nitrous oxide labor pain relief and satisfaction memory by a retrospective Visual Analog Scale (VAS, 0-10 Numeric Rating Scale) at a set cut off time of 3 months of a child's age.

RESULTS

Nitrous oxide use did not influence EPDS subscales upon discharge. Its use was instead associated with a lasting positive labor pain relief experience (VAS, 7.3 ± 2.2) in 83.5% of women, and labor satisfaction memory (VAS, 8.9 ± 1.8) in 90% of women, respectively, and with a significantly higher breastfeeding rates from the seventh day after discharge (p < .031), to the 1st (p < .043), and the third month of life (p < .016).

CONCLUSIONS

Nitrous oxide labor analgesia is associated with favorable effects on both women's psychoemotional experience of labor and breastfeeding success.

Should Nitrous Oxide Be Used for Laboring Patients?

Nitrous oxide, long used during labor in Europe, is gaining popularity in the United States. It offers many beneficial attributes, with few drawbacks. Cost, safety, and side effect profiles are favorable. Analgesic effectiveness is highly variable, yet maternal satisfaction is often high among the women who choose to use it. Despite being less effective in treating labor pain than neuraxial analgesic modalities, nitrous oxide serves the needs and preferences of a subset of laboring parturients. Nitrous oxide should, therefore, be considered for inclusion in the repertoire of modalities used to alleviate pain and facilitate effective coping during labor.

Remifentanil analgesia during external cephalic version for breech presentation in nulliparous women at term: A randomized controlled trial

BACKGROUND

The aim of the study was to assess the efficacy and safety of remifentanil for pain relief during external cephalic version (ECV) for breech presentation in nulliparous women at term.

METHODS

A total of 144 nulliparous women with singleton breech presentation were randomly divided into the intervention group and the placebo group, with 72 subjects in each group. The subjects in the intervention group received remifentanil (infused at 0.1 μg kg min with demand boluses of 0.1 μg/kg), whereas those in the placebo group were given saline placebo. This study was conducted from May 2013 to April 2016. The outcomes measures include pain (measured with the visual analog scale, VAS), success rate of ECV, maternal satisfaction for ECV, and adverse events.

RESULTS

A total of 137 participants completed the study. The intervention with remifentanil showed greater efficacy than did placebo in decreasing the VAS score immediately after ECV (intervention group 4.3 ± 2.2 vs placebo group 6.4 ± 2.5, P < 0.01). A significant difference in the ECV success rate was also found between the 2 groups (intervention group 56.9% vs placebo group 38.9%, P = 0.03). In addition, a significant difference in the satisfaction score was also detected (intervention group 9.3 ± 0.9 vs placebo group 6.7 ± 1.2, P < 0.01). The observed adverse events were similar between the 2 groups.

CONCLUSION

This study shows that remifentanil could decrease pain, improve the ECV success rate, and improve satisfaction in nulliparous women at term during the period of ECV. Furthermore, it is also well tolerated with few adverse events.

A randomized trial of remifentanil for analgesia in external cephalic version for breech presentation

BACKGROUND

Although external cephalic version (ECV) can be effective for correcting the fetus in a cephalic presentation, it may be painful for the mother. This study aimed to evaluate the efficacy and safety of remifentanil for pain relief during ECV in China.

METHODS

In all, 152 Chinese parturients with singleton breech presentation were randomly divided into 2 groups, each with 76 patients. All 152 patients were assigned to receive either remifentanil (infused at 0.1 μg/kg/min and demand boluses of 0.1 μg/kg) or saline placebo. The study was performed between January 2012 and December 2015. Outcome measurements included the Numerical Rating Pain Scale score (0-10) after ECV, success rate for ECV, and maternal satisfaction after ECV. Adverse events were also evaluated.

RESULTS

The study was completed by 146 patients. Remifentanil showed greater efficacy than placebo in decreasing the pain score immediately after ECV (remifentanil 4.6 ± 2.6 vs placebo 6.5 ± 2.7; P < 0.001). The success rate for ECV showed a significant difference between the 2 groups (remifentanil 56.5% vs placebo 39.5%; P = 0.04). Maternal satisfaction also showed a significant difference between the 2 groups (remifentanil 9.6 ± 1.4 vs placebo 6.4 ± 3.7; P < 0.001). However, the adverse events profiles were similar between both groups.

CONCLUSION

The results of this study demonstrate that remifentanil is an effective intervention for reducing pain, achieving successful ECV, and increasing maternal satisfaction during ECV, and is generally well-tolerated without additional adverse effects.

Analgesia for childbirth: modern insights into an age-old challenge and the quest for an ideal approach

SUMMARY It is widely recognized that childbirth may be the most painful experience in a woman’s lifetime and that women have a right to relief. There are many options, but the efficacy of only a few is supported by robust evidence. Many influences determine which method of pain relief is chosen, including social and cultural factors, availability, cost and personal preference. Due to human diversity and the differing perspectives of consumers, obstetric care providers and health administrators, there is no such thing as ‘an ideal approach’. In resource-rich societies, major advances in parturient safety and outcome flow from technique development and better monitoring. Greater awareness of the negative impact of untreated pain and of the relevance of genetic, cultural and social factors motivates research into better predictive models, novel therapies and optimization of existing methods.

Must we press on until a young mother dies? Remifentanil patient controlled analgesia in labour may not be suited as a "poor man's epidural"

BACKGROUND

The epidural route is still considered the gold standard for labour analgesia, although it is not without serious consequences when incorrect placement goes unrecognized, e.g. in case of intravascular, intrathecal and subdural placements. Until now there has not been a viable alternative to epidural analgesia especially in view of the neonatal outcome and the need for respiratory support when long-acting opioids are used via the parenteral route. Pethidine and meptazinol are far from ideal having been described as providing rather sedation than analgesia, affecting the cardiotocograph (CTG), causing fetal acidosis and having active metabolites with prolonged half-lives especially in the neonate. Despite these obvious shortcomings, intramuscular and intravenously administered pethidine and comparable substances are still frequently used in delivery units. Since the end of the 90 ths remifentanil administered in a patient-controlled mode (PCA) had been reported as a useful alternative for labour analgesia in those women who either don't want, can't have or don't need epidural analgesia.

DISCUSSION

In view of the need for conversion to central neuraxial blocks and the analgesic effect remifentanil has been demonstrated to be superior to pethidine. Despite being less effective in terms of the resulting pain scores, clinical studies suggest that the satisfaction with analgesia may be comparable to that obtained with epidural analgesia. Owing to this fact, remifentanil has gained a place in modern labour analgesia in many institutions. However, the fact that remifentanil may cause harm should not be forgotten when the use of this potent mu-agonist is considered for the use in labouring women. In the setting of one-to-one midwifery care, appropriate monitoring and providing that enough experience exists with this potent opioid and the treatment of potential complications, remifentanil PCA is a useful option in addition to epidural analgesia and other central neuraxial blocks. Already described serious consequences should remind us not refer to remifentanil PCA as a "poor man's epidural" and to safely administer remifentanil with an appropriate indication.

SUMMARY

Therefore, the authors conclude that economic considerations and potential cost-savings in conjunction with remifentanil PCA may not be appropriate main endpoints when studying this valuable method for labour analgesia.

Efficacy and safety of remifentanil as an alternative labor analgesic

The objective of this review was to evaluate the clinical efficacy and safety of remifentanil in the management of labor pain. Although neuraxial analgesia is the best option during labor, alternative analgesic options are needed for patients with contraindications. Using a systematic literature search, clinical outcomes of remifentanil for labor pain have been summarized. Also, comparisons of remifentanil to other options including meperidine, epidural analgesia, fentanyl, and nitrous oxide are provided. Based on the literature review, remifentanil is associated with high overall maternal satisfaction and favorable side-effect profile. However, due to the low reporting of adverse events, large, randomized controlled trials are needed to evaluate maternal and neonatal safety adequately and determine the optimal dosing needed to provide effective analgesia. While remifentanil is a feasible alternative for patients who cannot or do not want to receive epidural analgesia, administration should be monitored closely for potential adverse effects.

Efficacy and side effects of intravenous remifentanil patient-controlled analgesia used in a stepwise approach for labour: an observational study

BACKGROUND

Remifentanil has a suitable pharmacological profile for labour analgesia. In this prospective, observational study, intravenous patient-controlled analgesia with remifentanil, using stepwise bolus doses without background infusion, was examined during the first and second stages of labour. Outcomes were pain reduction, maternal satisfaction, maternal and neonatal side effects and remifentanil metabolism in the neonate.

METHODS

Parturients with normal term singleton pregnancies were recruited. The initial remifentanil bolus dose was 0.15 μg/kg, increasing in steps of 0.15 μg/kg, with a 2-min lock-out. Pain scores using a 100 mm visual analogue scale, systolic and diastolic blood pressures, respiratory rate and maternal sedation were recorded every 15 min. Maternal oxygen saturation and heart rate were monitored continuously. Neonatal data included Apgar scores, clinical examination, naloxone use, resuscitation, umbilical cord blood gases and remifentanil concentrations.

RESULTS

Forty-one parturients were enrolled. Pain scores were significantly reduced in the first 3 h of patient-controlled analgesia use compared to baseline, and at the end of the first and second stages of labour (P<0.05). Maximal pain reduction was 60% (P<0.01). One patient had inadequate pain relief and converted to epidural analgesia. The mean highest dose of remifentanil was 0.7 μg/kg [range 0.3-1.05]. Ninety-three percent of patients were satisfied with their analgesia. The lowest oxygen saturation was 91% and the lowest respiratory rate was 9 breaths/min. Eleven parturients (27%) received supplemental oxygen due to oxygen saturations <92%. Maternal sedation was moderate, and neonatal data reassuring.

CONCLUSIONS

Remifentanil intravenous patient-controlled analgesia provides adequate pain relief and high maternal satisfaction during the first and second stages of labour. Maternal sedation and respiratory depression may occur, but no serious neonatal side effects were recorded. Careful monitoring is mandatory.

Nitrous oxide as labor analgesia: clinical implications for nurses

A new interest in self-administered nitrous oxide for labor analgesia has emerged in recent years in the United States. It has been used widely in Europe for decades, with favorable results. The American College of Nurse-Midwives published a position statement in 2010 supporting the practice of self-administered nitrous oxide as an additional analgesia choice for laboring women. Recent literature on this subject has been directed toward midwives, obstetricians and/or anesthesiologists, with little emphasis for labor and delivery nurses. This article presents highlights of nursing care for women using self-administered nitrous oxide during labor and birth.

Combining nitrous oxide with carbon dioxide decreases the time to loss of consciousness during euthanasia in mice--refinement of animal welfare?

Carbon dioxide (CO(2)) is the most commonly used euthanasia agent for rodents despite potentially causing pain and distress. Nitrous oxide is used in man to speed induction of anaesthesia with volatile anaesthetics, via a mechanism referred to as the "second gas" effect. We therefore evaluated the addition of Nitrous Oxide (N(2)O) to a rising CO(2) concentration could be used as a welfare refinement of the euthanasia process in mice, by shortening the duration of conscious exposure to CO2. Firstly, to assess the effect of N(2)O on the induction of anaesthesia in mice, 12 female C57Bl/6 mice were anaesthetized in a crossover protocol with the following combinations: Isoflurane (5%)+O(2) (95%); Isoflurane (5%)+N(2)O (75%)+O(2) (25%) and N(2)O (75%)+O(2) (25%) with a total flow rate of 3 l/min (into a 7 l induction chamber). The addition of N(2)O to isoflurane reduced the time to loss of the righting reflex by 17.6%. Secondly, 18 C57Bl/6 and 18 CD1 mice were individually euthanized by gradually filling the induction chamber with either: CO(2) (20% of the chamber volume.min-1); CO(2)+N(2)O (20 and 60% of the chamber volume.min(-1) respectively); or CO(2)+Nitrogen (N(2)) (20 and 60% of the chamber volume.min-1). Arterial partial pressure (P(a)) of O(2) and CO(2) were measured as well as blood pH and lactate. When compared to the gradually rising CO(2) euthanasia, addition of a high concentration of N(2)O to CO(2) lowered the time to loss of righting reflex by 10.3% (P<0.001), lead to a lower P(a)O(2) (12.55 ± 3.67 mmHg, P<0.001), a higher lactataemia (4.64 ± 1.04 mmol.l(-1), P = 0.026), without any behaviour indicative of distress. Nitrous oxide reduces the time of conscious exposure to gradually rising CO(2) during euthanasia and hence may reduce the duration of any stress or distress to which mice are exposed during euthanasia.