Pharmacologic management of the opioid neonatal abstinence syndrome

THE EFFECTS OF BUPRENORPHINE AND MORPHINE DURING PREGNANCY: IMPACT OF EXPOSURE LENGTH ON MATERNAL BRAIN, BEHAVIOR, AND OFFSPRING NEURODEVELOPMENT

The escalating incidence of opioid-related issues among pregnant women in the United States underscores the critical necessity to understand the effects of opioid use and Medication for Opioid Use Disorders (MOUDs) during pregnancy. This research employed a translational rodent model to examine the impact of gestational exposure to buprenorphine (BUP) or morphine on maternal behaviors and offspring well-being. Female rats received BUP or morphine before conception, representing established use, with exposure continuing until postnatal day 2 or discontinued on gestational day 19 to mimic treatment cessation before birth. Maternal behaviors - including care, pup retrieval, and preference - as well as hunting behaviors and brain neurotransmitter levels were assessed. Offspring were evaluated for mortality, weight, length, milk bands, surface righting latency, withdrawal symptoms, and brain neurotransmitter levels. Our results reveal that regardless of exposure length (i.e., continued or discontinued), BUP resulted in reduced maternal care in contrast to morphine-exposed and control dams. Opioid exposure altered brain monoamine levels in the dams and offspring, and was associated with increased neonatal mortality, reduced offspring weight, and elevated withdrawal symptoms compared to controls. These findings underscore BUP's potential disruption of maternal care, contributing to increased pup mortality and altered neurodevelopmental outcomes in the offspring. This study calls for more comprehensive research into prenatal BUP exposure effects on the maternal brain and infant development with the aim to mitigate adverse outcomes in humans exposed to opioids during pregnancy.

Salivary Therapeutic Monitoring of Buprenorphine in Neonates After Maternal Sublingual Dosing Guided by Physiologically Based Pharmacokinetic Modeling

BACKGROUND

Opioid use disorder (OUD) during pregnancy is associated with high mortality rates and neonatal opioid withdrawal syndrome (NOWS). Buprenorphine, an opioid, is used to treat OUD and NOWS. Buprenorphine active metabolite (norbuprenorphine) can cross the placenta and cause neonatal respiratory depression (EC50 = 35 ng/mL) at high brain extracellular fluid (bECF) levels. Neonatal therapeutic drug monitoring using saliva decreases the likelihood of distress and infections associated with frequent blood sampling.

METHODS

An adult physiologically based pharmacokinetic model for buprenorphine and norbuprenorphine after intravenous and sublingual administration was constructed, vetted, and scaled to newborn and pregnant populations. The pregnancy model predicted that buprenorphine and norbuprenorphine doses would be transplacentally transferred to the newborns. The newborn physiologically based pharmacokinetic model was used to estimate the buprenorphine and norbuprenorphine levels in newborn plasma, bECF, and saliva after these doses.

RESULTS

After maternal sublingual administration of buprenorphine (4 mg/d), the estimated plasma concentrations of buprenorphine and norbuprenorphine in newborns exceeded the toxicity thresholds for 8 and 24 hours, respectively. However, the norbuprenorphine bECF levels were lower than the respiratory depression threshold. Furthermore, the salivary buprenorphine threshold levels in newborns for buprenorphine analgesia, norbuprenorphine analgesia, and norbuprenorphine hypoventilation were observed to be 22, 2, and 162 ng/mL.

CONCLUSIONS

Using neonatal saliva for buprenorphine therapeutic drug monitoring can facilitate newborn safety during the maternal treatment of OUD using sublingual buprenorphine. Nevertheless, the suitability of using adult values of respiratory depression EC50 for newborns must be confirmed.

Neonatal Abstinence Syndrome: An Insight Over Impact of Maternal Substance Use

Neonatal abstinence syndrome (NAS) highlights the intricate interplay between maternal substance use during pregnancy and the challenges neonates face from the distressing global opioid crisis. This comprehensive review captures the multilayered landscape of NAS, encircling its underlying mechanisms, epidemiology, diagnostic intricacies, clinical manifestations, continuing developmental impacts, treatment paradigms, and the crucial role of multidisciplinary care. The core pathophysiology of NAS involves the transplacental passage of addictive substances, activating chemical dependence in the maturing fetus, which is characterized by neurotransmitter dysregulation, neuroadaptations, and receptor sensitization. A diverse clinical presentation ranges from central nervous system hyperactivity and autonomic dysregulation to gastrointestinal manifestations, necessitating homogenous assessment tools such as the Finnegan Neonatal Abstinence Scoring System. The demand for a multilayered approach is essential for comprehensive management, involving pharmacological interventions like morphine or methadone and non-pharmacological strategies such as swaddling. The complications of NAS are not only limited to but are also well beyond infancy, leading to behavioral, longstanding cognitive, and socioemotional consequences. Addressing these developmental arcs demands decisive longitudinal monitoring and early interventions. NAS management is fundamentally multidisciplinary, requiring the teamwork of nurses, social workers, psychologists, pediatricians, and neonatologists. Apart from the clinical realm, managing the psychosocial needs of families traversing NAS requires resources and empathy. A crucial comprehensive approach is essential to confront the challenges and limitations of NAS. From early identification and prevention to longstanding support through pharmacological, non-pharmacological, and psychological channels, it creates a holistic structure that emerges as the basis for understanding the complicated relationship between maternal substance use and its impact on neonates. An amalgamation of community engagement, society, policy initiatives, and medical expertise is essential to mitigate the repercussions of NAS and adopt healthier outcomes for affected infants.

Compounded Nonsterile Preparations and FDA-Approved Commercially Available Liquid Products for Children: A North American Update

The purpose of this work was to evaluate the suitability of recent US Food and Drug Administration (US-FDA)-approved and marketed oral liquid, powder, or granule products for children in North America, to identify the next group of Active Pharmaceutical Ingredients (APIs) that have high potential for development as commercially available FDA-approved finished liquid dosage forms, and to propose lists of compounded nonsterile preparations (CNSPs) that should be developed as commercially available FDA-approved finished liquid dosage forms, as well as those that pharmacists should continue to compound extemporaneously. Through this identification and categorization process, the pharmaceutical industry, government, and professionals are encouraged to continue to work together to improve the likelihood that patients will receive high-quality standardized extemporaneously compounded CNSPs and US-FDA-approved products.

Comparison of Two Morphine Dosing Strategies in the Management of Neonatal Abstinence Syndrome

OBJECTIVE

The incidence of neonatal abstinence syndrome (NAS) has increased in recent years. Treatment approaches usually involve opioid replacement; however, the optimal treatment strategy is unknown. This study sought to determine the impact of weight- and symptom-based morphine dosing strategies on LOS and medication exposure in patients with NAS.

METHODS

A retrospective review was conducted from May 2015 to June 2017 at 2 NICUs within a health-system using different dosing approaches for NAS. Data were compared using Fisher exact tests for categorical data and t tests and Wilcoxon ranked sums for continuous data.

RESULTS

Baseline demographics were well-matched except for postmenstrual age at morphine initiation (p = 0.04). The weight-based group had a larger initial morphine dose (p < 0.001) and fewer number of steps to maximum morphine dose (p = 0.009). There were no differences between groups in LOS, number of dose adjustments, doses administered, weaning steps, maximum dose, or need to re-escalate dosing. There was also no difference between the first 3 modified Finnegan scores (MFS) after transferring patients to a neonatology service. Neonates with symptom-based dosing had a higher maximum MFS (p = 0.024). Neonates in the symptom-based group required adjunct therapy more often (p < 0.0001).

CONCLUSIONS

Data indicate the dosing strategy impacts number of steps to reach maximum dose and need for adjunctive therapy. Weight-based dosing may decrease the number of steps required to reach the morphine maximum dose and the need for adjunctive therapy by controlling NAS symptoms earlier.

Maternal Exposure and Neonatal Effects of Drugs of Abuse

The public health crisis of pregnant women being exposed to drugs of abuse and of its impact on their unborn children continues to grow at an alarming rate globally. The state of pregnancy is unique, with physiological changes that can lead to changes in the way drugs are handled by the body in both pharmacokinetics and response. These changes place the pregnant woman, fetus, and newborn infant at risk, as many of these drugs can cross the placenta and into breast milk. The substances most commonly linked to harmful effects include alcohol, tobacco, cannabis, stimulants, and opioids. The pharmacological and toxicological changes caused by in utero exposure or breastfeeding exposure are difficult to study, and the full extent of the mechanisms involved are not fully understood. However, these changes can significantly affect the risks of substance abuse and influence optimal treatment of pregnant women with a substance use disorder. In addition, newborns who were exposed to drugs of abuse in utero can experience withdrawal syndromes. Pharmacological management in infants is used to guide and treat withdrawal symptoms, with the goal being to improve the infant's sleep, eating, and comfort. Several barriers may prevent pregnant women from seeking help for substance use, including stigma and interactions with the legal system. Understanding changes in pharmacology, including pharmacokinetic changes that happen during pregnancy, is essential for anticipating the extent of maternal exposure and neonatal adverse effects.

Sedatives for opioid withdrawal in newborn infants

BACKGROUND

Neonatal abstinence syndrome (NAS) due to opioid withdrawal may result in disruption of the mother-infant relationship, sleep-wake abnormalities, feeding difficulties, weight loss, seizures and neurodevelopmental problems.

OBJECTIVES

To assess the effectiveness and safety of using a sedative versus control (placebo, usual treatment or non-pharmacological treatment) for NAS due to withdrawal from opioids and determine which type of sedative is most effective and safe for NAS due to withdrawal from opioids.

SEARCH METHODS

We ran an updated search on 17 September 2020 in CENTRAL via CRS Web and MEDLINE via Ovid. We searched clinical trials databases, conference proceedings and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

We included trials enrolling infants with NAS born to mothers with an opioid dependence with more than 80% follow-up and using randomised, quasi-randomised and cluster-randomised allocation to sedative or control.

DATA COLLECTION AND ANALYSIS

Three review authors assessed trial eligibility and risk of bias, and independently extracted data. We used the GRADE approach to assess the certainty of the evidence.

MAIN RESULTS

We included 10 trials (581 infants) with NAS secondary to maternal opioid use in pregnancy. There were multiple comparisons of different sedatives and regimens. There were limited data available for use in sensitivity analysis of studies at low risk of bias. Phenobarbital versus supportive care: one study reported there may be little or no difference in treatment failure with phenobarbital and supportive care versus supportive care alone (risk ratio (RR) 2.73, 95% confidence interval (CI) 0.94 to 7.94; 62 participants; very low-certainty evidence). No infant had a clinical seizure. The study did not report mortality, neurodevelopmental disability and adverse events. There may be an increase in days' hospitalisation and treatment from use of phenobarbital (hospitalisation: mean difference (MD) 20.80, 95% CI 13.64 to 27.96; treatment: MD 17.90, 95% CI 11.98 to 23.82; both 62 participants; very low-certainty evidence). Phenobarbital versus diazepam: there may be a reduction in treatment failure with phenobarbital versus diazepam (RR 0.39, 95% CI 0.24 to 0.62; 139 participants; 2 studies; low-certainty evidence). The studies did not report mortality, neurodevelopmental disability and adverse events. One study reported there may be little or no difference in days' hospitalisation and treatment (hospitalisation: MD 3.89, 95% CI -1.20 to 8.98; 32 participants; treatment: MD 4.30, 95% CI -0.73 to 9.33; 31 participants; both low-certainty evidence). Phenobarbital versus chlorpromazine: there may be a reduction in treatment failure with phenobarbital versus chlorpromazine (RR 0.55, 95% CI 0.33 to 0.92; 138 participants; 2 studies; very low-certainty evidence), and no infant had a seizure. The studies did not report mortality and neurodevelopmental disability. One study reported there may be little or no difference in days' hospitalisation (MD 7.00, 95% CI -3.51 to 17.51; 87 participants; low-certainty evidence) and 0/100 infants had an adverse event. Phenobarbital and opioid versus opioid alone: one study reported no infants with treatment failure and no clinical seizures in either group (low-certainty evidence). The study did not report mortality, neurodevelopmental disability and adverse events. One study reported there may be a reduction in days' hospitalisation for infants treated with phenobarbital and opioid (MD -43.50, 95% CI -59.18 to -27.82; 20 participants; low-certainty evidence). Clonidine and opioid versus opioid alone: one study reported there may be little or no difference in treatment failure with clonidine and dilute tincture of opium (DTO) versus DTO alone (RR 0.09, 95% CI 0.01 to 1.59; 80 participants; very low-certainty evidence). All five infants with treatment failure were in the DTO group. There may be little or no difference in seizures (RR 0.14, 95% CI 0.01 to 2.68; 80 participants; very low-certainty evidence). All three infants with seizures were in the DTO group. There may be little or no difference in mortality after discharge (RR 7.00, 95% CI 0.37 to 131.28; 80 participants; very low-certainty evidence). All three deaths were in the clonidine and DTO group. The study did not report neurodevelopmental disability. There may be little or no difference in days' treatment (MD -4.00, 95% CI -8.33 to 0.33; 80 participants; very low-certainty evidence). One adverse event occurred in the clonidine and DTO group. There may be little or no difference in rebound NAS after stopping treatment, although all seven cases were in the clonidine and DTO group. Clonidine and opioid versus phenobarbital and opioid: there may be little or no difference in treatment failure (RR 2.27, 95% CI 0.98 to 5.25; 2 studies, 93 participants; very low-certainty evidence). One study reported one infant in the clonidine and morphine group had a seizure, and there were no infant mortalities. The studies did not report neurodevelopmental disability. There may be an increase in days' hospitalisation and days' treatment with clonidine and opioid versus phenobarbital and opioid(hospitalisation: MD 7.13, 95% CI 6.38 to 7.88; treatment: MD 7.57, 95% CI 3.97 to 11.17; both 2 studies, 91 participants; low-certainty evidence). There may be little or no difference in adverse events (RR 1.55, 95% CI 0.44 to 5.40; 2 studies, 93 participants; very low-certainty evidence). However, there was oversedation only in the phenobarbital and morphine group; and hypotension, rebound hypertension and rebound NAS only in the clonidine and morphine group.

AUTHORS' CONCLUSIONS

There is very low-certainty evidence that phenobarbital increases duration of hospitalisation and treatment, but reduces days to regain birthweight and duration of supportive care each day compared to supportive care alone. There is low-certainty evidence that phenobarbital reduces treatment failure compared to diazepam and very low-certainty evidence that  phenobarbital reduces treatment failure compared to chlorpromazine. There is low-certainty evidence of an increase in days' hospitalisation and days' treatment with clonidine and opioid compared to phenobarbital and opioid. There are insufficient data to determine the safety and incidence of adverse events for infants treated with combinations of opioids and sedatives including phenobarbital and clonidine.

Opioid use during pregnancy can impair maternal behavior and the Maternal Brain Network: A literature review

Opioid Use Disorder (OUD) is a global epidemic also affecting women of reproductive age. A standard form of pharmacological treatment for OUD is Opioid Maintenance Therapy (OMT) and buprenorphine has emerged as the preferred treatment for pregnant women with OUD relative to methadone. However, the consequences of BUP exposure on the developing Maternal Brain Network and mother-infant dyad are not well understood. The maternal-infant bond is dependent on the Maternal Brain Network, which is responsible for the dynamic transition from a "nulliparous brain" to a "maternal brain". The Maternal Brain Network consists of regions implicated in maternal care (e.g., medial preoptic area, nucleus accumbens, ventral pallidum, ventral tegmentum area) and maternal defense (e.g., periaqueductal gray). The endogenous opioid system modulates many of the neurochemical changes in these areas during the transition to motherhood. Thus, it is not surprising that exogenous opioid exposure during pregnancy can be disruptive to the Maternal Brain Network. Though less drastic than misused opioids, OMTs may not be without risk of disrupting the neural and molecular structures of the Maternal Brain Network. This review describes the Maternal Brain Network as a framework for understanding how pharmacological differences in exogenous opioid exposure can disrupt the onset and maintenance of the maternal brain and summarizes opioid and OMT (in particular buprenorphine) use in the context of pregnancy and maternal behavior. This review also highlights future directions for evaluating exogenous opioid effects on the Maternal Brain Network in the hopes of raising awareness for the impact of the opioid crisis not only on exposed infants, but also on mothers and subsequent mother-infant bonds.

Transcutaneous Auricular Neurostimulation (tAN): A Novel Adjuvant Treatment in Neonatal Opioid Withdrawal Syndrome

Maternal opioid use during pregnancy is a growing national problem and can lead to newborns developing neonatal opioid withdrawal syndrome (NOWS) soon after birth. Recent data demonstrates that nearly every 15 min a baby is born in the United States suffering from NOWS. The primary treatment for NOWS is opioid replacement therapy, commonly oral morphine, which has neurotoxic effects on the developing brain. There is an urgent need for non-opioid treatments for NOWS. Transcutaneous auricular neurostimulation (tAN), a novel and non-invasive form of electrostimulation, may serve as a promising alternative to morphine. tAN is delivered via a multichannel earpiece electrode worn on and around the left ear, targeting two cranial nerves—the vagus and trigeminal nerves. Prior research suggests that auricular neurostimulation exerts an anxiolytic effect on the body by releasing endogenous opioids and reduces withdrawal symptoms in adults actively withdrawing from opioids. In this first-in-human prospective, open-label trial, we investigated tAN as an adjuvant to morphine therapy in eight infants >33 weeks gestational age suffering from NOWS and receiving oral morphine treatment. Infants received tAN for 30 min 1 h before receiving a morphine dose. tAN was delivered at 0.1 mA below perception intensity at two different nerve targets on the ear: Region 1, the auricular branch of the vagus nerve; and Region 2, the auriculotemporal nerve. tAN was delivered up to four times daily for a maximum of 12 days. The primary outcome measures were safety [heart rate monitoring, Neonatal Infant Pain Scale (NIPS), and skin irritation] and morphine length of treatment (LOT). tAN was well-tolerated and resulted in no unanticipated adverse events. Comparing to the national average of 23 days, the average oral morphine LOT was 13.3 days (median 9 days) and the average LOT after tAN initiation was 7 days (median 6 days). These preliminary data suggest that tAN is safe and may serve as a promising alternative adjuvant for treating NOWS and reducing the amount of time an infant receives oral morphine.

Clinical pharmacology and dosing regimen optimization of neonatal opioid withdrawal syndrome treatments

In this paper, we review the management of neonatal opioid withdrawal syndrome (NOWS) and clinical pharmacology of primary treatment agents in NOWS, including morphine, methadone, buprenorphine, clonidine, and phenobarbital. Pharmacologic treatment strategies in NOWS have been mostly empirical, and heterogeneity in dosing regimens adds to the difficulty of extrapolating study results to broader patient populations. As population pharmacokinetics (PKs) of pharmacologic agents in NOWS become more well‐defined and knowledge of patient‐specific factors affecting treatment outcomes continue to accumulate, PK/pharmacodynamic modeling and simulation will be powerful tools to aid the design of optimal dosing regimens at the patient level. Although there is an increasing number of clinical trials on the comparative efficacy of treatment agents in NOWS, here, we also draw attention to the importance of optimizing the dosing regimen, which can be arguably equally important at identifying the optimal treatment agent.

Feasibility of auricular acupressure as an adjunct treatment for neonatal opioid withdrawal syndrome (NOWS)

BACKGROUND

The opioid epidemic in the United States continues to threaten public health. As a result of this crisis, neonatal opioid withdrawal syndrome (NOWS) has risen exponentially and requires a multitude of non-pharmacologic treatments to ensure healthy neonatal outcomes. Methods: This feasibility study implemented an acupressure protocol as informed by the Near-Term Infant (NTI) conceptual framework for the treatment of NOWS. Aims of this study were to assess provider training, effective integration of acupressure within the standard of care, and acceptance of this treatment by mothers and healthcare providers. Results: With maternal consent, a total of 12 participants were enrolled and underwent auricular acupressure. Nurse Practitioners were credentialed (75%) and effectively administered neonatal acupressure (100%) in accordance with the study protocol. Mothers were very satisfied with acupressure for the treatment of NOWS (Client Satisfaction Questionaire-8 mean scores 3.8-4.0 of a possible 4.0), and the majority of healthcare providers were supportive (66%, mean scores 3.6 to 4.0 out of possible 5). Conclusions: Auricular acupressure was successfully implemented within the standard of care for NOWS. Future studies should incorporate outlined suggestions and include qualitative measures of acceptance as well as randomized controlled trials to evaluate efficacy.

Salivary cortisol levels as a biomarker for severity of withdrawal in opioid-exposed newborns

BACKGROUND

Scoring tools used to quantify withdrawal in infants with neonatal abstinence syndrome (NAS) are often confounded by subjective measurements. This study assessed salivary cortisol as an objective biomarker of withdrawal severity in opioid-exposed newborns.

METHODS

A prospective study was conducted in 25 full-term opioid-exposed newborns monitored for NAS. Morning and evening salivary cortisol levels were collected starting within 48 h post birth until initiation of pharmacologic treatment for withdrawal (Pre-Treatment) or when the infant was discharged without pharmacotherapy (No Treatment).

RESULTS

Cortisol levels in the Pre-Treatment group (n = 11) were significantly higher within the first week of life (median 1.74 µg/dl) than in the No Treatment group (n = 11; median 0.72 µg/dl; P = 0.003); three infants had inadequate saliva volume for cortisol assay. Cortisol significantly decreased after 72 h post birth among infants discharged without pharmacotherapy (≤72 h median 1.25 µg/dl; ≥72 h median 0.58 µg/dl; P = 0.022), whereas cortisol remained elevated for infants subsequently treated for severity of withdrawal. No cortisol circadian rhythm was observed for either group.

CONCLUSIONS

Salivary cortisol in opioid-exposed newborns may provide an index of stress and help identify infants who will have more severe clinical presentation of NAS. Such a biomarker would allow risk stratification for early treatment and discharge decisions.

Pharmacokinetic and pharmacodynamic considerations in developing a response to the opioid epidemic

Introduction: Opioids continue to be used widely for pain management. Widespread availability of prescription opioids has led to opioid abuse and addiction. Besides steps to reduce inappropriate prescribing, exploiting opioid pharmacology to make their use safer is important.Areas covered: This article discusses the pathology and factors underlying opioid abuse. Pharmacokinetic and pharmacodynamic properties affecting abuse liability of commonly abused opioids have been highlighted. These properties inform the development of ideal abuse deterrent products. Mechanisms and cost-effectiveness of available abuse deterrent products have been reviewed in addition to the pharmacology of medications used to treat addiction.Expert opinion: The opioid crisis presents unique challenges to managing pain effectively given the limited repertoire of strong analgesics. The 5-point strategy to combat the opioid crisis calls for better preventive, treatment, and recovery services, better data, better pain management, better availability of overdose-reversing drugs and better research. There is an urgent need to decrease the cost of abuse deterrent opioids which deters their cost-effectiveness. In addition, discovery of novel analgesics, further insight into central and peripheral pain mechanisms, understanding genomic risk profiles for efficient targeted efforts, and education will be key to winning this fight against the opioid crisis.

Stories of Loss: Separation of Children and Mothers Who Use Opioids

In the present article, we examine the experiences of women who use opioids and have lost children to governing agencies or family members with a focus on access to resources. We conducted 28 qualitative interviews with mothers who misused opioids and lost custody of their children. Their narratives are analyzed within a social capital framework. Mothers with both negative and positive social capital, whose children were removed, desired to regain their maternal role. However, mothers with negative social capital had increased difficulty navigating the judicial system and accessing needed services, were less likely to remain in treatment, more likely to use drugs, and less likely to regain custody of their children than women with positive social capital. We suggest that medical, social, and law enforcement agencies do more to link mothers who misuse opioids with positive social capital in order to increase their participation and retention in treatment and help keep families intact.

Clinical Decision Support to Improve Dosing Weight Use in Infants with Neonatal Abstinence Syndrome

Supplemental Digital Content is available in the text.

Introduction:

Opioid abuse in the United States is a public health emergency. From 2000 to 2009, prenatal maternal opiate use increased from 1.19 to 5.63 per 1,000 births, with up to 80% of in utero opioid-exposed infants requiring pharmacotherapy. This study aimed to increase the percentage of neonatal abstinence syndrome (NAS) medication orders based on birth weight (BW) in neonates admitted to a neonatal intensive care unit with a principal diagnosis of NAS from 29% to 90%, within 4 months of project initiation, and to sustain this for 6 months.

Methods:

This project occurred at an academic medical center with 5,000 deliveries per year and a 49-bed Level III neonatal intensive care unit. We used the Institute for Healthcare Improvement methodology, largely focusing interventions on clinical decision support (CDS) tools. We plotted all measures on Shewhart charts, and Nelson rules differentiated special versus common cause variation.

Results:

The percent of orders based on BW increased from 29% to 78% after implementing multiple interventions focused primarily on CDS. However, this later decreased to 48% as workarounds began. There was also a significant decrease in the length of stay variability, which persisted throughout the project.

Discussion:

CDS is a helpful tool to guide prescribing behavior; however, workarounds can negate its usefulness. Standardized use of BW for weight-based NAS medication prescribing can decrease the length of stay variability. Further studies are needed using a human factors approach to minimize workarounds in CDS and potentially decrease the length of stay in neonates with NAS.

Methadone dosing strategies in preterm neonates can be simplified

AIMS

A dramatic increase in newborn infants with neonatal abstinence syndrome has been observed and these neonates are frequently treated with complex methadone dosing schemes to control their withdrawal symptoms. Despite its abundant use, hardly any data on the pharmacokinetics (PK) of methadone is available in preterm neonates. Therefore we investigated developmental PK of methadone and evaluated current dosing strategies and possible simplification in this vulnerable population.

METHODS

A single-centre open-label prospective study was performed to collect PK data after a single oral dose of methadone in preterm neonates. A population PK model was built to characterize developmental PK of (R)- and (S)-methadone. Model-based simulations were performed to identify a simplified dosing strategy to reach and maintain target methadone exposure.

RESULTS

A total of 121 methadone concentrations were collected from 31 preterm neonates. A one-compartment model with first order absorption and elimination kinetics best described PK data for (R)- and (S)-methadone. Clearance increases with advancing gestational age and differs between R- and S-enantiomer, being slightly higher for the former (0.244 vs 0.167 L/h). Preterm neonates reached target exposure after 48 hours with currently used dosing schedules. Output from simulations revealed that target exposures can be achieved with a simplified dosing strategy during the first 4 days of treatment.

CONCLUSION

Methadone clearance in preterm neonates increases with advancing gestational age and its disposition is influenced by its chirality. Simulations that account for developmental PK changes indicate a shorter methadone dosing strategy can maintain target exposure to control withdrawal symptoms.

Shining a Light: Integrating Protocols Into Clinical Practice for Treatment of Neonatal Abstinence Syndrome

BACKGROUND AND PURPOSE

The epidemic use of opioids is negatively influencing the health of the American people. Pregnant women and their unborn babies have not escaped the ravages of substance use. A dramatic increase in maternal opioid use has led to an increasing number of infants experiencing withdrawal symptoms known as neonatal abstinence syndrome (NAS). The purpose of this article is to highlight best practice for the management of infants with opioid withdrawal.

REVIEW OF PROTOCOLS AND TREATMENTS

Review of available protocols and treatments revealed wide variation in the treatment of NAS and little use of standardized guidelines or protocols, despite current recommendations of the American Academy of Pediatrics. There is supporting evidence showing that the use of standardized protocols reduces the length of treatment and enhances outcomes in the neonatal population.

EVIDENCE-BASED RECOMMENDATIONS

Evidence-based strategies to address gaps in practice include developing strong protocols to identify infants at risk and implementing standardized plans when treating NAS. Consistent assessment, initial treatment with nonpharmacologic measures, and conservative use of pharmacologic agents are important elements to an NAS treatment protocol.

CONCLUSIONS AND IMPLICATIONS

In evaluating the current literature for best practice in the management of the newborn with opioid withdrawal, it is clear that evidence-based standardized protocols need to be in place for the best treatment of the mother-infant dyad, caring for both the infants with NAS as well as the mothers with opioid use disorder.

Morphine vs Methadone Treatment for Infants with Neonatal Abstinence Syndrome

OBJECTIVE

To estimate the relationship of initial pharmacotherapy with methadone or morphine and length of stay (LOS) in infants with neonatal abstinence syndrome (NAS) admitted to the neonatal intensive care unit (NICU).

STUDY DESIGN

From the Pediatrix Clinical Data Warehouse database, we identified all infants born at ≥36 weeks of gestation between 2011 and 2015 who were diagnosed with NAS (International Classification of Diseases, Ninth Revision code 779.5) and treated with methadone or morphine in the first 7 days of life. We used multivariable Cox proportional hazards regression analysis to quantify the association between initial treatment and LOS after adjusting for maternal age, maternal race/ethnicity, maternal drug use, maternal smoking, gestational age, small for gestational age status, inborn status, and discharge year.

RESULTS

We identified a total of 7667 eligible infants, including 1187 treated with methadone (15%) and 6480 treated with morphine (85%). Birth weight, gestational age, and sex were similar in the 2 groups. Methadone treatment was associated with a 22% shorter median LOS (18 days [IQR, 11-30 days] vs 23 days [IQR, 16-33]; P < .001) and a 19% shorter median NICU stay (17 days [IQR, 10-29 days] vs 21 days [IQR, 14-36 days]; P < .001). After adjustment, methadone was associated with a shorter LOS (hazard ratio for discharge, 1.24; 95% CI, 1.11-1.37; P < .001) CONCLUSION: Among infants born at ≥36 weeks of gestation with NAS, initial methadone treatment was associated with a shorter LOS compared with morphine treatment. Future prospective comparative effectiveness trials to treat infants with NAS are needed to verify this observation.

Neonatal abstinence syndrome

Neonatal abstinence syndrome refers to the signs and symptoms attributed to the cessation of prenatal exposure (via placental transfer) to various substances. This Primer focuses on neonatal abstinence syndrome caused by opioid use during pregnancy - neonatal opioid withdrawal syndrome (NOWS). As the global prevalence of opioid use has alarmingly increased, so has the incidence of NOWS. NOWS can manifest with varying severity or not at all, for unknown reasons, but is likely to be associated with multiple factors, both maternal (for example, smoking and additional substance exposures) and neonatal (gestational age, sex and genetics). Care for the infant with NOWS begins with addressing the issues experienced by pregnant women with opioid use disorder. Co-occurring mental illness, economic hardship, intimate partner violence, infectious diseases and limited access to care are common in these women and can result in poor maternal and neonatal outcomes. Although there is no consensus regarding optimal NOWS management, non-pharmacological interventions (such as breastfeeding and rooming-in of the mother and the baby) have become a priority, as they can ameliorate symptoms without the need for further opioid exposure. Untreated NOWS can be associated with morbidity in early infancy, and the long-term consequences of fetal opioid exposure are only beginning to be understood.

The Impact of Breastfeeding on Health Outcomes for Infants Diagnosed with Neonatal Abstinence Syndrome: A Review

Neonatal abstinence syndrome (NAS) is a neurologic condition resulting from prenatal exposure to opioids. The sudden cessation of opioids in neonates can lead to withdrawal symptoms affecting the neurologic, respiratory, and gastrointestinal systems. Rising opioid use in the United States has led to an increased incidence of infants born with NAS. Despite the growing incidence of NAS, there is a lack of standardized guidelines for intervention and management. Recent studies suggest that non-pharmacological methods should be used as first-line interventions for the reduction of NAS symptoms. Of the non-pharmacological methods, growing literature suggests that breastfeeding may have the potential to reduce symptom severity and improve outcomes. We searched the PubMed and Medline databases for experimental/quasi-experimental studies published from 1997-2018 regarding outcomes in breastfed versus formula-fed neonates with prenatal exposure to opioids. Seven retrospective studies fulfilling the inclusion criteria were reviewed. Collectively, the studies show a strong correlation between breastfeeding and a reduced length of hospital stay, a decreased severity of NAS presentation, and a decreased necessity of pharmacological interventions in infants diagnosed with NAS. From these findings, we recommend breastfeeding as an integral component of the early management of NAS.

Update of the Scientific Opinion on opium alkaloids in poppy seeds

Poppy seeds are obtained from the opium poppy (Papaver somniferum L.). They are used as food and to produce edible oil. The opium poppy plant contains narcotic alkaloids such as morphine and codeine. Poppy seeds do not contain the opium alkaloids, but can become contaminated with alkaloids as a result of pest damage and during harvesting. The European Commission asked EFSA to provide an update of the Scientific Opinion on opium alkaloids in poppy seeds. The assessment is based on data on morphine, codeine, thebaine, oripavine, noscapine and papaverine in poppy seed samples. The CONTAM Panel confirms the acute reference dose (ARfD) of 10 μg morphine/kg body weight (bw) and concluded that the concentration of codeine in the poppy seed samples should be taken into account by converting codeine to morphine equivalents, using a factor of 0.2. The ARfD is therefore a group ARfD for morphine and codeine, expressed in morphine equivalents. Mean and high levels of dietary exposure to morphine equivalents from poppy seeds considered to have high levels of opium alkaloids (i.e. poppy seeds from varieties primarily grown for pharmaceutical use) exceed the ARfD in most age groups. For poppy seeds considered to have relatively low concentrations of opium alkaloids (i.e. primarily varieties for food use), some exceedance of the ARfD is also seen at high levels of dietary exposure in most surveys. For noscapine and papaverine, the available data do not allow making a hazard characterisation. However, comparison of the dietary exposure to the recommended therapeutical doses does not suggest a health concern for these alkaloids. For thebaine and oripavine, no risk characterisation was done due to insufficient data. However, for thebaine, limited evidence indicates a higher acute lethality than for morphine and the estimated exposure could present a health risk.

Neonatal Abstinence Syndrome: Presentation and Treatment Considerations

The increase in opioid use among the general population is reflected in pregnant women and neonatal abstinence syndrome (NAS) statistics. This increase has produced an unprecedented focus on NAS from both the political-judicial sphere and the medical community. Under the banner of fetal protection, judges and prosecutors have implemented punitive approaches against women who use prescribed and nonprescribed opioids during pregnancy, including arrest, civil commitment, detention, prosecution, and loss of custody or termination of parental rights. Within the medical community, questions have been raised regarding protocols to detect prenatal drug exposure at delivery, NAS treatment protocols, the need for quality-improvement strategies to standardize care and reduce length of stay for mother and infant, and the benefits of engaging the mother in the care of her infant. It is not uncommon for the expression of strong discordant views on these issues both between and among these political-judicial and medical constituencies. Closely examining the issues often reveal a lack of understanding of substance use disorders, their treatment, and the occurrence and treatment of NAS. This study provides an in-depth examination of NAS, including variations in presentation and factors that impact the efficacy of treatment, and also identifying questions that remain unanswered. Finally, 4 key areas on which future research should focus to guide both medical care and public policy are discussed.

Pharmacokinetics of Oral Methadone in the Treatment of Neonatal Abstinence Syndrome: A Pilot Study

OBJECTIVE

To characterize the population pharmacokinetics of oral methadone in neonates requiring pharmacologic treatment of neonatal abstinence syndrome and to develop a pharmacokinetic (PK) model toward an evidence-based treatment protocol.

STUDY DESIGN

Based on a methadone dosing protocol, serum concentrations of methadone and its metabolites were assessed by high performance liquid chromatography-tandem mass spectrometry from dried blood spots. Population PK analysis was performed to determine the volume of distribution and clearance of oral methadone. Methadone plasma concentration-time profiles were simulated from the deduced PK model to optimize the dosing regimen.

RESULTS

There was substantial interindividual variability in methadone concentrations. Blood concentrations of methadone were best described by a 1-compartment model with first-order absorption. The population mean estimates (coefficient of variation percentage) for oral clearance and volume of distribution were 8.94 (103%) L/h/70 kg and 177 (133%) L/70 kg, respectively. Optimized dosing strategies were developed based on the simulated PK profiles. We suggest a starting dose of 0.1 mg/kg per dose every 6 hours for most patients requiring pharmacologic treatment of neonatal abstinence syndrome followed by an expedited weaning phase.

CONCLUSIONS

The proposed dosing regimen may reduce the cumulative dose of opioid and shorten the length of hospitalization. Future studies should aim to validate the simulated dosing schemes with clinical data and expand our understanding of the between-patient PK variability.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01754324.

Population Pharmacokinetic Model of Sublingual Buprenorphine in Neonatal Abstinence Syndrome

OBJECTIVE

Neonatal abstinence syndrome (NAS)--a clinical entity of infants from in utero exposure to psychoactive xenobiotic and buprenorphine--has been successfully used to treat NAS. However, nothing is known about the pharmacokinetics (PK) of buprenorphine in neonates with NAS. To our knowledge, this is the first study to investigate the population pharmacokinetic of sublingual buprenorphine in neonates with NAS.

DESIGN

A retrospective population PK analysis of: (1) neonates with NAS treated with sublingual buprenorphine in randomized, double blinded clinical study and (2) data from healthy adults from a previously published pharmacokinetic study.

SETTING

Neonatal intensive care unit and general clinical research unit.

PATIENTS

Twenty-four neonates with NAS and five healthy adults.

INTERVENTIONS

All participants received sublingual buprenorphine per study protocol.

MEASUREMENTS AND MAIN RESULTS

A total of 303 PK data from 29 neonates and adults were used for model development. A population pharmacokinetic analysis was conducted using a first order conditional estimation with interaction in the NONMEM software program. A two-compartment linear PK model with first-order absorption process best described the pharmacokinetics of sublingual buprenorphine in neonates. The apparent clearance (CL) of buprenorphine was linearly related to body weight and matured with increasing age via two distinct saturated pathways. A typical neonate with NAS (body weight, 2.9 kg; postnatal age; 5.4 days) had a CL of 3.5 L/kg/hour and elimination half-life of 11 hours. Phenobarbital did not affect the clearance of buprenorphine compared to neonates of similar age and weight.

CONCLUSIONS

This is the first study to investigate the population PK of sublingual buprenorphine in neonatal NAS. To our knowledge, this is also the first report to describe the age-dependent changes of buprenorphine PK in this patient population. No buprenorphine dose adjustment is needed for neonates with NAS treated with buprenorphine and concurrent phenobarbital.

Phenobarbital versus morphine in the management of neonatal abstinence syndrome, a randomized control trial

BACKGROUNDS

Evaluating the efficacy of the loading and tapering dose of Phenobarbital versus oral Morphine in the management of NAS.

METHODS

This randomized, open-label, controlled trial was conducted on 60 neonates born to illicit drugs dependent mothers at Vali-Asr and Akbar-Abadi hospitals, Tehran, Iran, who exhibited NAS requiring medical therapy. The neonates were randomized to receive either: Oral Morphine Sulfate or a loading dose of Phenobarbital followed by a tapering dose. The duration of treatment required for NAS resolution, the total hospital stay and the requirement for additional second line treatment were compared between the treatment groups.

RESULTS

The Mean ± Standard Deviation for the duration of treatment required for the resolution of NAS was 8.5 ± 5 days in the Morphine group and 8.5 ± 4 days in the Phenobarbital group (P = 0.9). The duration of total hospital stay was 12.6 ± 5.6 days in the Morphine group and 12.5 ± 5.3 days in the Phenobarbital group (P = 0.7). 3.3 % in the Morphine group versus 6.6 % in the Phenobarbital group required adjunctive treatment (P = 0.5).

CONCLUSIONS

There were no significant differences in the duration of treatment, duration of hospital stay, and the requirement for adjunctive treatment, between the neonates with NAS who received Morphine Sulfate and neonates who received a loading and tapering dose of Phenobarbital.

TRIAL REGISTRATION

This study is registered at the Iranian Registry of Clinical Trials ( www.irct.ir ) which is a Primary Registry in the WHO Registry Network. (Registration Number =  IRCT201406239568N8 ).

Neonatal opioid withdrawal syndrome

Neonatal opioid withdrawal syndrome is common due to the current opioid addiction epidemic. Infants born to women covertly abusing prescription opioids may not be identified as at risk until withdrawal signs present. Buprenorphine is a newer treatment for maternal opioid addiction and appears to result in a milder withdrawal syndrome than methadone. Initial treatment is with nonpharmacological measures including decreasing stimuli, however pharmacological treatment is commonly required. Opioid monotherapy is preferred, with phenobarbital or clonidine uncommonly needed as adjunctive therapy. Rooming-in and breastfeeding may decease the severity of withdrawal. Limited evidence is available regarding long-term effects of perinatal opioid exposure.

Variation in treatment of neonatal abstinence syndrome in US children's hospitals, 2004-2011

OBJECTIVE

Neonatal abstinence syndrome (NAS) is a drug withdrawal syndrome experienced by opioid-exposed infants. There is no standard treatment for NAS and surveys suggest wide variation in pharmacotherapy for NAS. Our objective was to determine whether different pharmacotherapies for NAS are associated with differences in outcomes and to determine whether pharmacotherapy and outcome vary by hospital.

STUDY DESIGN

We used the Pediatric Health Information System Database from 2004 to 2011 to identify a cohort of infants with NAS requiring pharmacotherapy. Mixed effects hierarchical negative binomial models evaluated the association between pharmacotherapy and hospital with length of stay (LOS), length of treatment (LOT) and hospital charges, after adjusting for socioeconomic variables and comorbid clinical conditions.

RESULT

Our cohort included 1424 infants with NAS from 14 children's hospitals. Among hospitals in our sample, six used morphine, six used methadone and two used phenobarbital as primary initial treatment for NAS. In multivariate analysis, when compared with NAS patients initially treated with morphine, infants treated with methadone had shorter LOT (incidence rate ratio (IRR) = 0.55; P < 0.0001) and LOS (IRR = 0.60; P < 0.0001). Phenobarbital as a second-line agent was associated with increased LOT (IRR = 2.09; P<0.0001), LOS (IRR = 1.78; P < 0.0001) and higher hospital charges (IRR = 1.84; P < 0.0001). After controlling for case-mix, hospitals varied in LOT, LOS and hospital charges.

CONCLUSION

We found variation in hospital in treatment for NAS among major US children's hospitals. In analyses controlling for possible confounders, methadone as initial treatment was associated with reduced LOT and hospital stay.

Design considerations for point-of-care clinical trials comparing methadone and buprenorphine treatment for opioid dependence in pregnancy and for neonatal abstinence syndrome

RATIONALE

In recent years, the U.S. has experienced a significant increase in the prevalence of pregnant opioid-dependent women and of neonatal abstinence syndrome (NAS), which is caused by withdrawal from in-utero drug exposure. While methadone-maintenance currently is the standard of care for opioid dependence during pregnancy, research suggests that buprenorphine-maintenance may be associated with shorter infant hospital lengths of stay (LOS) relative to methadone-maintenance. There is no "gold standard" treatment for NAS but there is evidence that buprenorphine, relative to morphine or methadone, treatment may reduce LOS and length of treatment.

DESIGN

Point-of-care clinical trial (POCCT) designs, maximizing external validity while reducing cost and complexity associated with classic randomized clinical trials, were selected for two planned trials to compare methadone to buprenorphine treatment for opioid dependence during pregnancy and for NAS. This paper describes design considerations for the Medication-assisted treatment for Opioid-dependent expecting Mothers (MOMs; estimated N = 370) and Investigation of Narcotics for Ameliorating Neonatal abstinence syndrome on Time in hospital (INFANTs; estimated N = 284) POCCTs, both of which are randomized, intent-to-treat, two-group trials. Outcomes would be obtained from participants' electronic health record at three participating hospitals. Additionally, a subset of infants in the INFANTs POCCT would be from mothers in the MOMs POCCT and, thus, potential interaction between medication treatment of mother and infant could be evaluated.

CONCLUSION

This pair of planned POCCTs would evaluate the comparative effectiveness of treatments for opioid dependence during pregnancy and for NAS. The results could have a significant impact on practice.

Neonatal abstinence syndrome

Neonatal abstinence syndrome (NAS) is a result of the sudden discontinuation of fetal exposure to substances that were used or abused by the mother during pregnancy. Withdrawal from licit or illicit substances is becoming more common among neonates in both developed and developing countries. NAS continues to be an important clinical entity throughout much of the world. NAS leads to a constellation of signs and symptoms involving multiple systems. The pathophysiology of NAS is not completely understood. Urine or meconium confirmation may assist the diagnosis and management of NAS. The Finnegan scoring system is commonly used to assess the severity of NAS; scoring can be helpful for initiating, monitoring, and terminating treatment in neonates. Nonpharmacological care is the initial treatment option, and pharmacological treatment is required if an improvement is not observed after nonpharmacological measures or if the infant develops severe withdrawal. Morphine is the most commonly used drug in the treatment of NAS secondary to opioids. An algorithmic approach to the management of infants with NAS is suggested. Breastfeeding is not contraindicated in NAS, unless the mother is taking street drugs, is involved in polydrug abuse, or is infected with HIV. Future studies are required to assess the long-term effects of NAS on children after prenatal exposure.

Care of the infant with neonatal abstinence syndrome: strength of the evidence

There is little empirical evidence that guides management of infants with neonatal abstinence syndrome. The standard of care first described in the 1970s is still prevalent today, although it has never been tested in this population. Standard of care interventions include decreasing external stimulation, holding, nonnutritive sucking, swaddling, pressure/rubbing, and rocking. These interventions meet the goals of nonpharmacologic interventions, which are to facilitate parental attachment and decrease external stimuli. Many nursing interventions used in infants with neonatal abstinence syndrome have been tested in low-birth-weight infants, whose treatment often includes the same goals. Those interventions include music therapy, kangaroo care, massage, and use of nonoscillating water beds. Nursing attitude has also been shown to be impactful on parental attachment. The American Academy of Pediatrics recommends breast-feeding in infants whose mothers are on methadone who do not have any other contraindication. It also provides guidelines for pharmacologic management but cannot provide specific recommendations about a standard first dose, escalation, or weaning schedule. Buprenorphine has some evidence about its safety in newborns with neonatal abstinence syndrome, but high-powered studies on its efficacy are currently lacking. There are many opportunities for both evidence-based projects and nursing research projects in this population.

Care of Drug-Addicted Pregnant Women: Current Concepts and Future Strategies – an Overview

This review focuses on drug use during pregnancy and the perinatal period, a constellation that is seen more often. Drug use in pregnant women poses an increased risk for adverse health outcomes both for the mother and child. Care is often complicated by social and environmental factors, as well as psychiatric comorbidities. It is, therefore, very important to provide drug-using pregnant women with optimal ante-, peri- and post-natal care. Health professionals should approach them in a nonjudgmental and supportive way, and provide them with the same care and attention as nondrug-using women. Adequate care requires interdisciplinary teams. Ideally, healthcare providers should be specialized in the care of drug-using pregnant women.

Management of neonatal abstinence syndrome from opioids

Most infants at risk for neonatal abstinence syndrome have opioid plus another drug exposure; polypharmacy is the rule rather than the exception. Scales for evaluation of neonatal abstinence syndrome are primarily based for opioid withdrawal. A standard protocol to treat neonatal abstinence syndrome has not been developed. Institute nonpharmacologic strategies for all neonates at risk. The American Academy of Pediatrics recommends mechanism-directed therapy (treat opioid withdrawal with an opioid) as the first-line therapy. Second-line medications are currently under evaluation.

Babies breaking bad: neonatal and iatrogenic withdrawal syndromes

PURPOSE OF REVIEW

This review will summarize the symptoms, evaluation, and treatment of neonatal and iatrogenic withdrawal syndromes.

RECENT FINDINGS

Buprenorphine is emerging as the drug of choice for maintaining opioid-dependent women during pregnancy, because of its association with less severe withdrawal symptoms. Recent findings suggest it may be the drug of choice for treating the opioid-exposed neonate as well.

SUMMARY

Healthcare workers should be cognizant of the risk factors for neonatal abstinence syndrome (NAS), as well as its symptoms, so that nonpharmalogic and pharmacologic therapies can be initiated. With increased emphasis on pain control in children, it is likely that iatrogenic withdrawal will continue to be a concern, and healthcare workers should understand the similarities and differences between this and NAS.