Sudden infant death syndrome in infants of substance-abusing mothers

Sleep-Related Sudden Unexpected Infant Death Among Infants Prenatally Substance Exposed

BACKGROUND AND OBJECTIVES

Maternal substance use during pregnancy heightens risk of sudden unexpected infant death (SUID), including through unsafe sleep practices. Families impacted by substance use frequently experience disproportionate social drivers of poor health and family vulnerability likely contributory to fatality risk. Characteristics of sleep-related SUID among infants born prenatally substance exposed versus nonexposed were compared to identify targeted prevention opportunities.

METHODS

Using the Sudden Death in the Young Registry, we examined SUID with sleep-related death between 2015 and 2020 across infants prenatally exposed versus nonexposed. Distribution of sleep environment characteristics, social drivers of poor health, and family vulnerability factors were examined using descriptive statistics and χ2.

RESULTS

Of 2010 infants who experienced sleep-related deaths, 283 (14%) were prenatally exposed. More than half of deaths involved an adult bed (52%, n = 1045) or surface sharing with an adult (53%, n = 1074). Supervisors of prenatally exposed infants were disproportionately impaired at infant death versus nonexposed (34%, n = 97 vs 16%, n = 279). Statistically significant associations between prenatal exposure history and vulnerability factors (insurance, child welfare involvement, intimate partner violence, health care barriers) were identified (P < .05).

CONCLUSIONS

Sleep-related SUID across infants prenatally exposed versus nonexposed differ in sleep environment characteristics and contributory social vulnerability. Disproportionate sleep environment hazards (surface sharing, supervisor impairment) are identified among prenatally exposed infants that should compel targeted prevention efforts, including safe sleep messaging, discouraging surface sharing, and engaging support persons during impairment periods. Addressing social needs and family vulnerability are also paramount to increase access to health care, safe sleep education, and material resource provision.

A retrospective review of methylamphetamine detected in child deaths reported to the Victorian Coroner, Australia

This study investigated methylamphetamine (MA) exposures in the deaths of children (≤ 12 years old) reported to the Coroner in the state of Victoria, Australia, between 2011 and 2020. Demographics, autopsy findings including the cause of death, self-reported prenatal or caregiver drug use, child protection services information, and toxicological findings were summarized by descriptive statistics. Validated methods of liquid chromatography-tandem mass spectrometry were used in the analysis of drugs. There were 50 child deaths with MA detected in blood, urine, and/or hair with 64% (n = 32) identified in 2018-2020. Most children were 1-365 days old (66%, n = 33) and the cause of death was unascertained in 62% (n = 31) of cases. MA was toxicologically confirmed in hair (94%, n = 47) significantly more than blood (18%, n = 9). Prenatal or caregiver drug use was self-reported in 44% (n = 22) and 42% (n = 21) of cases, respectively. Moreover, only 54% (n = 27) of deceased children were a child protection client at their time of death. These findings suggest the number of deceased children exposed to MA has increased over the past 10 years, which is consistent with the greater supply of crystal MA in the Australian community. Hair analysis provided additional means to identify cases that were unknown to child protection services and may have implications for other children in the same drug exposure environment.

Drivers of decision-making regarding infant sleep practices among mothers with opioid use disorder

OBJECTIVE

To understand the perspectives and perceived facilitators of and barriers to following safe infant sleeping practices among mothers with opioid use disorder (OUD).

STUDY DESIGN

Using the Theory of Planned Behavior (TPB) framework, we conducted qualitative interviews with mothers with OUD regarding infant sleep practices. We created codes and generated themes, concluding data collection upon achieving thematic saturation.

RESULTS

Twenty-three mothers with infants 1-7 months of age were interviewed from 08/2020 to 10/2021. Mothers chose sleeping practices they perceived made their infants safer, more comfortable, and minimized infant withdrawal symptoms. Mothers in residential treatment facilities were influenced by facility infant sleep rules. Hospital sleep modeling and varied advice by providers, friends and family influenced maternal decisions.

CONCLUSIONS

Mothers reported factors unique to their experience with OUD that influenced their decisions about infant sleep that should be considered when developing tailored interventions to promote safe infant sleep in this population.

Understanding cigarette smoking among mothers with opioid use disorder

BACKGROUND

Cigarette smoking is highly prevalent among mothers with opioid use disorder (OUD). Organizations such as the American College of Obstetrics and Gynecology recommend cessation of cigarettes during the pre- and postnatal periods. Factors that inform decisions to continue or stop smoking cigarettes among pregnant and postpartum mothers with OUD are unclear.

AIMS

This study aimed to understand (1) the lived experience of mothers with OUD regarding cigarette smoking and (2) barriers and facilitators to reduction of cigarette smoking during the pre- and postnatal periods.

METHODS

Guided by the Theory of Planned Behavior (TPB) framework, we completed semi-structured, in-depth interviews with mothers with OUD with infants 2-7 months of age. We used an iterative approach to analysis by conducting interviews and developing and revising codes and themes until we reached thematic saturation.

RESULTS

Fifteen of 23 mothers reported smoking cigarettes prenatally and postnatally, 6 of 23 smoked cigarettes during the prenatal period only, and 2 mothers were non-smokers. We found that mothers: 1) believed that smoke exposure had negative health consequences and may exacerbate withdrawal symptoms for their infants; 2) implemented risk mitigation practices, which were dictated both by themselves and by outside rules, to reduce the harmful effects of smoke around infants; 3) were motivated to quit or cut-down on smoking because of the desire to optimize the health and well-being of their infants; 4) continued to smoke because they felt that the stress related to caregiving and their own recovery were a higher priority than quitting smoking; and 5) were influenced by exposure to smokers with whom they lived, as well as by the varied advice of medical providers, family, and friends.

CONCLUSION

While mothers with OUD acknowledged the negative health impact of cigarette smoke exposure to their infants, many experienced stressors related to recovery and caregiving unique to those with OUD that impacted their cigarette smoking behaviors.

SIDS is associated with prenatal drug use: a meta-analysis and systematic review of 4 238 685 infants

OBJECTIVE

To conduct a meta-analysis to determine the association between prenatal drug exposure and risk of sudden infant death syndrome (SIDS).

DESIGN

Studies were searched using PubMed, Medline and Embase and restricted to English, with no publication date limit. Selected studies included published cohort, population or case studies comparing the incidence of SIDS among drug-exposed with drug-free controls. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-Analysis of Observational Studies in Epidemiology guidelines. Data were pooled using a random-effects model to evaluate risk ratios (RR).

SETTING

High-income countries.

PATIENTS

Children with a history of prenatal drug exposure.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

RR of SIDS between drug-exposed and control infants.

RESULTS

Sixteen studies (36 730 infants with any prenatal drug exposure, 21 661 exposed to opioids, 21 571 exposed to cocaine, 5031 exposed to methadone compared with 4 201 955 with no exposure). Any prenatal drug exposure was associated with an increased crude risk of SIDS (RR 7.84, 95% CI 5.21 to 11.81). Prenatal opioid exposure had the highest associative crude risk of SIDS (RR 9.76, 95% CI 5.28 to 18.05), followed by methadone (RR 9.52, 95% CI 4.60 to 19.70) and cocaine (RR 4.40, 95% CI 2.52 to 7.67). Increased crude risk persisted after adjusting for socioeconomic factors (RR 4.24, 95% CI 1.39 to 12.88). The incidence of SIDS for this cohort decreased between 1972 and 2020 but remained significantly higher than controls.

CONCLUSION

Exposure to any drug of dependency during pregnancy is associated with an increased risk of SIDS after controlling for socioeconomic factors. Further study to evaluate mechanisms and contribution of other confounders (eg, smoking) is warranted.

Evidence Base for 2022 Updated Recommendations for a Safe Infant Sleeping Environment to Reduce the Risk of Sleep-Related Infant Deaths

Every year in the United States, approximately 3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Statistical Classification of Diseases and Related Health Problems 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths have remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. In addition, additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, which is included in this issue.

Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment

Each year in the United States, ∼3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Classification of Diseases, 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths has remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. Additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is also included. The recommendations and strength of evidence for each recommendation are included in this policy statement. The rationale for these recommendations is discussed in detail in the accompanying technical report.

Home Cardiorespiratory Monitoring in Infants at Risk for Sudden Infant Death Syndrome (SIDS), Apparent Life-Threatening Event (ALTE) or Brief Resolved Unexplained Event (BRUE)

Sudden infant death syndrome (SIDS) is defined as the sudden death of an infant younger than one year of age which remains unexplained after a thorough case investigation, including performance of a complete autopsy, examination of the death scene, and review of the clinical history. About 90% of SIDS occur before six months of age, the peak incidence is between two and four months, and the median age for death is elven weeks. The clinical, social, and economic relevance of SIDS, together with the evidence that prevention of this syndrome was possible, has significantly stimulated research into risk factors for the development of SIDS in the hope of being able to introduce new effective preventive measures. This narrative review discusses the potential relationships between apparent life-threatening events (ALTE) or brief resolved unexplained events (BRUE) and SIDS development, and when a home cardiorespiratory monitor is useful for prevention of these conditions. A literature analysis showed that home cardiorespiratory monitoring has been considered a potential method to identify not only ALTE and BRUE but SIDS also. ALTE and BRUE are generally due to underlying conditions that are not detectable in SIDS infants. A true relationship between these conditions has never been demonstrated. Use of home cardiorespiratory monitor is not recommended for SIDS, whereas it could be suggested for children with previous ALTE or severe BRUE or who are at risk of the development of these conditions. However, use of home cardiorespiratory monitors assumes that family members know the advantages and limitations of these devices after adequate education and instruction in their use.

Sleep-disordered breathing in patients on opioids for chronic pain

The past two decades has seen a substantial rise in the use of opioids for chronic pain, along with opioid-related mortality and adverse effects. A contributor to opioid-associated mortality is the high prevalence of moderate/severe sleep-disordered breathing, including central sleep apnea and obstructive sleep apnea, in patients with chronic pain. Although evidence-based treatments are available for sleep-disordered breathing, patients are not frequently assessed for sleep-disordered breathing in pain clinics. To aid healthcare providers in this area of clinical uncertainty, we present evidence on the interaction between opioids and sleep-disordered breathing, and the prevalence and predictive factors for sleep-disordered breathing in patients on opioids for chronic pain. We provide recommendations on how to evaluate patients on opioids for risk of moderate/severe sleep-disordered breathing in clinical care, which could lead to earlier use of therapeutic interventions for opioid-associated sleep-disordered breathing, such as opioid cessation or positive airway pressure therapy. This would improve quality of life and well-being of patients with chronic pain.

Perinatal exposure to ethanol in rats induces permanent disturbances of breathing and chemosensitivity during adulthood

Perinatal exposure to drugs of abuse, including alcohol (ethanol), is known to impinge the development of respiratory function. However, most studies described the short-term effects of these exposures, focusing mostly on the early postnatal life. After exposure to ethanol during gestation and lactation we have previously shown that 3-4 week-old rat exhibit chronic hypoventilation and an altered response to hypoxia at the end of ethanol exposure. However, whether these deficits are reversible following ethanol withdrawal remained unknown. Here, we investigated through whole-body plethysmography the respiratory activity of 2 months-old rats exposed to ethanol from gestation to weaning followed by one month of ethanol withdrawal. After ethanol withdrawal, rats persistently exhibited a significant reduction in respiratory frequency without change in tidal volume associated to a lower arterial blood oxygen content. In addition, the response to hypoxia in these rats was reduced whereas the response to hypercapnia remained unaltered. In conclusion perinatal exposure to ethanol in rats, unlike exposure to cocaine, morphine or nicotine, is characterized by selective alterations of basal respiratory activity and chemosensitivity that persist long after withdrawal.

Predictive factors for sleep apnoea in patients on opioids for chronic pain

Background

The risk of death is elevated in patients taking opioids for chronic non-cancer pain. Respiratory depression is the main cause of death due to opioids and sleep apnoea is an important associated risk factor.

Methods

In chronic pain clinics, we assessed the STOP-Bang questionnaire (a screening tool for sleep apnoea; Snoring, Tiredness, Observed apnoea, high blood Pressure, Body mass index, age, neck circumference and male gender), Epworth Sleepiness Scale, thyromental distance, Mallampati classification, daytime oxyhaemoglobin saturation (SpO₂) and calculated daily morphine milligram equivalent (MME) approximations for each participant, and performed an inlaboratory polysomnogram. The primary objective was to determine the predictive factors for sleep apnoea in patients on chronic opioid therapy using multivariable logistic regression models.

Results

Of 332 consented participants, 204 underwent polysomnography, and 120 (58.8%) had sleep apnoea (AHI ≥5) (72% obstructive, 20% central and 8% indeterminate sleep apnoea), with a high prevalence of moderate (23.3%) and severe (30.8%) sleep apnoea. The STOP-Bang questionnaire and SpO₂ are predictive factors for sleep apnoea (AHI ≥15) in patients on opioids for chronic pain. For each one-unit increase in the STOP-Bang score, the odds of moderate-to-severe sleep apnoea (AHI ≥15) increased by 70%, and for each 1% SpO₂ decrease the odds increased by 33%. For each 10 mg MME increase, the odds of Central Apnoea Index ≥5 increased by 3%, and for each 1% SpO₂ decrease the odds increased by 45%.

Conclusion

In patients on opioids for chronic pain, the STOP-Bang questionnaire and daytime SpO₂ are predictive factors for sleep apnoea, and MME and daytime SpO₂ are predictive factors for Central Apnoea Index ≥5.

Trial registration number

NCT02513836

Short-term health outcomes of newborn infants of substance-using mothers in Australia and New Zealand: A systematic review

AIM

Substance use is not unusual among women of childbearing age. Pregnant women who use a substance and the consequent impacts on a newborn vary across studies and settings. We reviewed New Zealand and Australian literature to examine the short-term health outcomes of newborn of substance-using mothers and their demographic characteristics.

METHODS

Five medical/nursing databases and google scholar were searched in April 2017. Studies were considered eligible if they described outcomes of newborn of substance-using mothers. Mixed Methods Appraisal Tool was used for quality assessment of candidate studies. Relevant data were extracted and analyzed using narrative synthesis. Based on data availability, a subset of studies was included in meta-analysis.

RESULTS

Although findings of individual studies vary, there are some evidence that the infants born to substance-using mothers were likely to have preterm birth, low birthweight, small-for-gestational age, low Apgar score, and admission to neo-natal intensive care unit. The likelihood of adverse health outcomes was much higher for newborns of polysubstance-using mothers, than newborns of mothers using a single substance. Pregnant women who use illicit substance are predominantly socially disadvantaged, in their twenties and or of Aboriginal descent.

CONCLUSION

Infants of substance-using mothers suffer a range of adverse health outcomes. Multidisciplinary and integrated approach of services that ensure supportive social determinants of health may result in a better outcome for newborn and positive behavioral change among mothers.

The effects of sleeping position, maternal smoking and substance misuse on the ventilatory response to hypoxia in the newborn period

BACKGROUND

Maternal smoking, substance misuse in pregnancy and prone sleeping increase the risk of sudden infant death syndrome (SIDS). We examined the effect of maternal smoking, substance misuse and sleeping position on the newborn response to hypoxia.

METHODS

Infants born between 36 and 42 weeks of gestational age underwent respiratory monitoring in the prone and supine sleeping position before and during a hypoxic challenge. Minute ventilation (MV) and end-tidal carbon dioxide (ETCO₂) levels were assessed.

RESULTS

Sixty-three infants were studied: 22 controls, 23 whose mothers smoked and 18 whose mothers substance-misused and smoked. In the supine position, baseline MV was higher and ETCO₂ levels were lower in infants of substance-misusing mothers compared to controls (p = 0.015, p = 0.017, respectively). Infants of substance-misusing mothers had a lower baseline MV and higher ETCO₂ levels in the prone position (p = 0.005, p = 0.004, respectively). When prone, the rate of decline in minute ventilation in response to hypoxia was greater in infants whose mothers substance-misused and smoked compared to controls (p = 0.002) and infants of smoking mothers (p = 0.016).

CONCLUSION

The altered response to hypoxia in the prone position of infants whose mothers substance-misused and smoked in pregnancy may explain their increased vulnerability to SIDS.

Central and peripheral chemoreceptors in sudden infant death syndrome

The pathogenesis of sudden infant death syndrome (SIDS) has been ascribed to an underlying biological vulnerability to stressors during a critical period of development. This paper reviews the main data in the literature supporting the role of central (e.g. retrotrapezoid nucleus, serotoninergic raphe nuclei, locus coeruleus, orexinergic neurons, ventral medullary surface, solitary tract nucleus) and peripheral (e.g. carotid body) chemoreceptors in the pathogenesis of SIDS. Clinical and experimental studies indicate that central and peripheral chemoreceptors undergo critical development during the initial postnatal period, consistent with the age range of SIDS (<1 year). Most of the risk factors for SIDS (gender, genetic factors, prematurity, hypoxic/hyperoxic stimuli, inflammation, perinatal exposure to cigarette smoke and/or substance abuse) may structurally and functionally affect the developmental plasticity of central and peripheral chemoreceptors, strongly suggesting the involvement of these structures in the pathogenesis of SIDS. Morphometric and neurochemical changes have been found in the carotid body and brainstem respiratory chemoreceptors of SIDS victims, together with functional signs of chemoreception impairment in some clinical studies. However, the methodological problems of SIDS research will have to be addressed in the future, requiring large and highly standardized case series. Up-to-date autopsy protocols should be produced, involving substantial, and exhaustive sampling of all potentially involved structures (including peripheral arterial chemoreceptors). Morphometric approaches should include unbiased stereological methods with three-dimensional probes. Prospective clinical studies addressing functional tests and risk factors (including genetic traits) would probably be the gold standard, allowing markers of intrinsic or acquired vulnerability to be properly identified.

New Frameworks for Understanding Sudden Unexpected Deaths in Infancy (SUDI) in Socially Vulnerable Families

THEORETICAL PRINCIPLES

Sociological frameworks may enhance understanding of the complex and multidimensional nature of disadvantage, which is prevalent among families who experience Sudden Unexpected Death in Infancy (SUDI).

PHENOMENA ADDRESSED

SUDI is the largest category of postneonatal death and largely associated with the social determinants of health. The highly successful 'Back to Sleep' campaign has resulted in a more than 85% decrease in SUDI. However, social inequalities have accompanied this decrease, and the burden of SUDI now lies with the most disadvantaged and socially vulnerable families. A considerable body of research on the phenomena of SUDI and disadvantage has been published over the last decade, demonstrating the widening social gradient in SUDI, and the importance in recognising structural factors and the multifactorial nature of disadvantage. Gaps in understanding of risk factors and scepticism about the received wisdom of health professionals have emerged as central themes in understanding why socially vulnerable families may adopt unsafe infant care practices. The direct impact of social disadvantage on infant care has also been recognised.

RESEARCH LINKAGES

The translation of epidemiological findings regarding SUDI risk into public health recommendations for health professionals and families alike has to date focused on eliminating individual level risk behaviours. Unfortunately, such a model largely ignores the broader social, cultural, and structural contexts in which such behaviours occur. Translating the new knowledge offered by sociological frameworks and the principles of behavioural economics into evidence based interventions may assist in the reduction of SUDI mortality in our most socially vulnerable families.

Beyond "Back to Sleep": Ways to Further Reduce the Risk of Sudden Infant Death Syndrome

Sudden infant death syndrome (SIDS) remains the leading cause of postneonatal mortality in the United States, despite reduction in rates of more than 50% since the initiation of the "Back to Sleep" (now called "Safe to Sleep") campaign in 1994. In recent years, the rate of decline in SIDS deaths has plateaued, even with the ongoing educational efforts that promote safe sleep and other risk reduction measures. The 2016 American Academy of Pediatrics guidelines for reducing the risk of SIDS focus heavily on sleep practices, bedding, and location, but also include factors that often receive less attention (ie, prenatal care, maternal smoking, alcohol and drug use, and childhood vaccinations). This review describes these factors that are less often addressed and identifies interventions that have resulted in positive behavioral changes that not only benefit infants, but also promote the health and well-being of their mothers. [Pediatr Ann. 2017;46(8):e284-e290.].

Antenatal smoking and substance-misuse, infant and newborn response to hypoxia

OBJECTIVES

To determine at the peak age for sudden infant death syndrome (SIDS) the ventilatory response to hypoxia of infants whose mothers substance misused in pregnancy (SM infants), or smoked during pregnancy (S mothers) and controls whose mothers neither substance misused or smoked. In addition, we compared the ventilatory response to hypoxia during the neonatal period and peak age of SIDS.

WORKING HYPOTHESIS

Infants of S or SM mothers compared to control infants would have a poorer ventilatory response to hypoxia at the peak age of SIDS.

STUDY DESIGN

Prospective, observational study.

PATIENT-SUBJECT SELECTION

Twelve S; 12 SM and 11 control infants were assessed at 6-12 weeks of age and in the neonatal period.

METHODOLOGY

Changes in minute volume, oxygen saturation, heart rate, and end tidal carbon dioxide levels on switching from breathing room air to 15% oxygen were assessed. Maternal and infant urine samples were tested for cotinine, cannabinoids, opiates, amphetamines, methadone, cocaine, and benzodiazepines.

RESULTS

The S and SM infants had a greater decline in minute volume (P = 0.037, P = 0.016, respectively) and oxygen saturation (P = 0.031) compared to controls. In all groups, the magnitude of decline in minute volume in response to hypoxia was higher in the neonatal period compared to at 6-12 weeks (P < 0.001).

CONCLUSIONS

Both maternal substance misuse and smoking were associated with an impaired response to a hypoxic challenge at the peak age for SIDS. The hypoxic ventilatory decline was more marked in the neonatal period compared to the peak age for SIDS indicating a maturational effect. Pediatr Pulmonol. 2017;52:650-655. © 2016 Wiley Periodicals, Inc.

SIDS and Other Sleep-Related Infant Deaths: Evidence Base for 2016 Updated Recommendations for a Safe Infant Sleeping Environment

Approximately 3500 infants die annually in the United States from sleep-related infant deaths, including sudden infant death syndrome (SIDS), ill-defined deaths, and accidental suffocation and strangulation in bed. After an initial decrease in the 1990s, the overall sleep-related infant death rate has not declined in more recent years. Many of the modifiable and nonmodifiable risk factors for SIDS and other sleep-related infant deaths are strikingly similar. The American Academy of Pediatrics recommends a safe sleep environment that can reduce the risk of all sleep-related infant deaths. Recommendations for a safe sleep environment include supine positioning, use of a firm sleep surface, room-sharing without bed-sharing, and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include avoidance of exposure to smoke, alcohol, and illicit drugs; breastfeeding; routine immunization; and use of a pacifier. New evidence and rationale for recommendations are presented for skin-to-skin care for newborn infants, bedside and in-bed sleepers, sleeping on couches/armchairs and in sitting devices, and use of soft bedding after 4 months of age. In addition, expanded recommendations for infant sleep location are included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, "SIDS and Other Sleep-Related Infant Deaths: Updated 2016 Recommendations for a Safe Infant Sleeping Environment," which is included in this issue.

Antenatal substance misuse and smoking and newborn hypoxic challenge response

OBJECTIVES

Infants of smoking (S) and substance misusing (SM) mothers have an increased risk of sudden infant death syndrome. The aim of this study was to test the hypothesis that infants of SM or S mothers compared with infants of non-SM, non-smoking mothers (controls) would have a poorer ventilatory response to hypoxia, which was particularly marked in the SM infants.

DESIGN

Physiological study.

SETTING

Tertiary perinatal centre.

PATIENTS

21 SM; 21 S and 19 control infants. Infants were assessed before maternity/neonatal unit discharge.

INTERVENTIONS

Maternal and infant urine samples were tested for cotinine, cannabinoids, opiates, amphetamines, methadone, cocaine and benzodiazepines.

MAIN OUTCOME MEASURES

During quiet sleep, the infants were switched from breathing room air to 15% oxygen and changes in minute volume were assessed.

RESULTS

The SM infants had a greater mean increase (p=0.028, p=0.034, respectively) and a greater magnitude of decline (p<0.001, p=0.018, respectively) in minute volume than the S infants and the controls. The rate of decline in minute volume was greater in the SM infants (p=0.008) and the S infants (p=0.011) compared with the controls.

CONCLUSIONS

Antenatal substance misuse and smoking affect the infant's ventilatory response to a hypoxic challenge.

Ventilatory response to hypercarbia in newborns of smoking and substance-misusing mothers

RATIONALE

Infants of mothers who smoked (S) or substance misused (SM) during pregnancy have an increased risk of sudden infant death syndrome (SIDS).

OBJECTIVES

To test the hypothesis that infants of S and SM mothers compared with infants of non-substance-misusing, nonsmoking mothers (control subjects) would have a reduced ventilatory response to hypercarbia and that any reduction would be greater in the SM infants.

METHODS

Infants were assessed before maternity/neonatal unit discharge. Maternal and infant urine samples were obtained and tested for cotinine, cannabinoids, opiates, amphetamines, methadone, cocaine, and benzodiazepines.

MEASUREMENTS AND MAIN RESULTS

Respiratory flow and Vt were measured using a pneumotachograph inserted into a face mask placed over the infant's mouth and nose. The ventilatory responses to three levels of inspired carbon dioxide (0 [baseline], 2, and 4% CO2) were assessed. Twenty-three SM, 34 S, and 22 control infants were assessed. The birth weight of the control subjects was higher than the SM and S infants (P = 0.017). At baseline, SM infants had a higher respiratory rate (P = 0.003) and minute volume (P = 0.007) compared with control subjects and S infants. Both the SM and S infants had a lower ventilatory response to 2% (P < 0.001) and 4% (P < 0.001) CO2 than the control subjects. The ventilatory response to CO2 was lower in the SM infants compared with the S infants (P = 0.009).

CONCLUSIONS

These results are consistent with infants of smoking mothers and substance misuse/smoking mothers having a dampened ventilatory response to hypercarbia, which is particularly marked in the latter group.

Sleep-disordered breathing and psychiatric disorders

Sleep-disordered breathing, the commonest form of which is obstructive sleep apnoea (OSA) is increasingly recognised as a treatable cause of morbidity. It shares many risk factors with psychiatric disorders including behaviours such as smoking and physical comorbidity. Many symptoms of the two overlap, leaving OSA often undetected and undertreated. In the few studies that assess the two, OSA is commonly comorbid with depression (17-45%) and schizophrenia (up to 55%) and possibly bipolar. There is some limited evidence that treating OSA can ameliorate psychiatric symptoms. Some psychotropics, such as narcotics, cause sleep-disordered breathing (SDB), whilst weight-inducing neuroleptics may exacerbate it. An extreme form of SDB, sudden infant death syndrome (SIDS), is a risk in mothers with substance abuse. Being aware of these common comorbidities may help improve psychiatric patient's treatment and quality of life.

The carotid body in Sudden Infant Death Syndrome

The aim of the present study is to provide a review of cytochemical, clinical and experimental data indicating disruption of perinatal carotid body maturation as one of the possible mechanisms underlying SIDS pathogenesis. SIDS victims have been reported to show alterations in respiratory regulation which may partly be ascribed to peripheral arterial chemoreceptors. Carotid body findings in SIDS victims, although not entirely confirmed by other authors, have included reductions in glomic tissue volume and cytoplamic granules of type I cells, changes in cytological composition (higher percentages of progenitor and type II cells) and increases in dopamine and noradrenaline contents. Prematurity and environmental factors, such as exposure to tobacco smoke, substances of abuse, hyperoxia and continuous or intermittent hypoxia, increase the risk of SIDS and are known to affect carotid body functional and structural maturation adversely, supporting a role for peripheral arterial chemoreceptors in SIDS.

SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment

Despite a major decrease in the incidence of sudden infant death syndrome (SIDS) since the American Academy of Pediatrics (AAP) released its recommendation in 1992 that infants be placed for sleep in a nonprone position, this decline has plateaued in recent years. Concurrently, other causes of sudden unexpected infant death occurring during sleep (sleep-related deaths), including suffocation, asphyxia, and entrapment, and ill-defined or unspecified causes of death have increased in incidence, particularly since the AAP published its last statement on SIDS in 2005. It has become increasingly important to address these other causes of sleep-related infant death. Many of the modifiable and nonmodifiable risk factors for SIDS and suffocation are strikingly similar. The AAP, therefore, is expanding its recommendations from being only SIDS-focused to focusing on a safe sleep environment that can reduce the risk of all sleep-related infant deaths including SIDS. The recommendations described in this report include supine positioning, use of a firm sleep surface, breastfeeding, room-sharing without bed-sharing, routine immunization, consideration of a pacifier, and avoidance of soft bedding, overheating, and exposure to tobacco smoke, alcohol, and illicit drugs. The rationale for these recommendations is discussed in detail in this technical report. The recommendations are published in the accompanying "Policy Statement--Sudden Infant Death Syndrome and Other Sleep-Related Infant Deaths: Expansion of Recommendations for a Safe Infant Sleeping Environment," which is included in this issue (www.pediatrics.org/cgi/doi/10.1542/peds.2011-2220).

SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment

Despite a major decrease in the incidence of sudden infant death syndrome (SIDS) since the American Academy of Pediatrics (AAP) released its recommendation in 1992 that infants be placed for sleep in a nonprone position, this decline has plateaued in recent years. Concurrently, other causes of sudden unexpected infant death that occur during sleep (sleep-related deaths), including suffocation, asphyxia, and entrapment, and ill-defined or unspecified causes of death have increased in incidence, particularly since the AAP published its last statement on SIDS in 2005. It has become increasingly important to address these other causes of sleep-related infant death. Many of the modifiable and nonmodifiable risk factors for SIDS and suffocation are strikingly similar. The AAP, therefore, is expanding its recommendations from focusing only on SIDS to focusing on a safe sleep environment that can reduce the risk of all sleep-related infant deaths, including SIDS. The recommendations described in this policy statement include supine positioning, use of a firm sleep surface, breastfeeding, room-sharing without bed-sharing, routine immunizations, consideration of using a pacifier, and avoidance of soft bedding, overheating, and exposure to tobacco smoke, alcohol, and illicit drugs. The rationale for these recommendations is discussed in detail in the accompanying "Technical Report--SIDS and Other Sleep-Related Infant Deaths: Expansion of Recommendations for a Safe Infant Sleeping Environment," which is included in this issue of Pediatrics (www.pediatrics.org/cgi/content/full/128/5/e1341).

Risk factors for sudden infant death syndrome in a developing country

OBJECTIVE: To analyze whether previously identified risk factors for sudden death syndrome have a significant impact in a developing country. METHODS: Retrospective longitudinal case-control study carried out in Porto Alegre, Southern Brazil. Cases (N=39) were infants born between 1996 and 2000 who died suddenly and unexpectedly at home during sleep and were diagnosed with sudden death syndrome. Controls (N=117) were infants matched by age and sex who died in hospitals due to other conditions. Data were collected from postmortem examination records and questionnaires answers. A conditional logistic model was used to identify factors associated with the outcome. RESULTS: Mean age at death of cases was 3.2 months. The frequencies of infants regarding gestational age, breastfeeding and regular medical visits were similar in both groups. Sleeping position for most cases and controls was the lateral one. Supine sleeping position was found for few infants in both groups. Maternal variables, age below 20 years (OR=2, 95% CI: 1.1; 5.1) and smoking of more than 10 cigarettes per day during pregnancy (OR=3, 95% CI: 1.3; 6.4), significantly increased the risk for the syndrome. Socioeconomic characteristics were similar in both groups and did not affect risk. CONCLUSIONS: Infant-maternal and socioeconomic profiles of cases in a developing country closely resembled the profile described in the literature, and risk factors were similar as well. However, individual characteristics were identified as risks in the population studied, such as smoking during pregnancy and maternal age below 20 years.

Sudden infant death syndrome in infants of cocaine using mothers

A study of Sudden Infant Death Syndrome (SIDS) with maternal cocaine exposure was undertaken using the perinatal medical records at the University of Miami/Jackson Memorial Medical Center and case files of the Metropolitan Dade County Medical Examiner Department, Miami, Florida USA from 1988-1992. 78 SIDS cases were analysed. 18 infants were classified as cocaine-exposed SIDS infants with positive history of maternal cocaine abuse and/or positive urine toxicology; 50 infants were classified as cocaine-negative SIDS infants without the history and with negative toxicology. The incidence of SIDS among cocaine-exposed infants was estimated to be higher than that of cocaine-negative infants overall (p < 0.025), but statistical significance between the groups was not confirmed when controlled for ethnicity. No significant differences of birth weight, estimated gestational age, body and brain weights were observed at autopsy between the two groups. Cocaine-exposed SIDS cases included 6 infants born small for gestational age (p < 0.05). 10 of 18 cocaine-exposed SIDS infants had a positive result for urine toxicology at birth and died younger aged than cocaine-negative infants (p < 0.05). Toxicology tests of the specimens obtained from cadavers were all negative for cocaine metabolites.

Opioids, sleep architecture and sleep-disordered breathing

Opioid use whether acute or chronic, illicit or therapeutic is prevalent in Western societies. Opioid receptors are located in the same nuclei that are active in sleep regulation and opioid peptides are suggested to be involved in the induction and maintenance of the sleep state. mu-Opioids are the most commonly used opioids and are recognized respiratory depressants that cause abnormal awake ventilatory responses to hypercapnia and hypoxia. Abnormal sleep architecture has been reported during the process of opioids induction, maintenance and withdrawal. During induction and maintenance of opioid use there is reduction of rapid eye movement (REM) sleep and slow wave sleep. More recently, central sleep apnoea (CSA) has been reported with chronic opioid use and 30% of stable methadone maintenance treatment patients have CSA. Given these facts, it is sobering to note the paucity of human data available regarding the effects of short and long-term opioid use on sleep architecture and respiration during sleep. In this manuscript, we review the current knowledge regarding the effects of mu-opioids on sleep and respiration during sleep and suggest research pathways to advance our knowledge and to explore the possible responsible mechanisms related to these effects.

Sudden infant death syndrome

Sudden infant death syndrome (SIDS) continues to be the most common cause of postneonatal infant death. SIDS is a complex, multifactorial disorder, the cause of which is still not fully understood. However, much is known now about environmental risk factors, some of which are modifiable. These include maternal and antenatal risk factors such as smoking during pregnancy, as well as infant-related risk factors such as non-supine sleeping position and soft bedding. Emerging evidence also substantiates an expanding number of genetic risk factors. Interactions between environmental and genetic risk factors may be of critical importance in determining an infant's actual risk of SIDS. Although no practical way exists to identify which infants will die of SIDS, nor is there a safe and proven prevention strategy even if identification were feasible, reducing exposure to modifiable risk factors has helped to lower the incidence of SIDS. Current challenges include wider dissemination of guidelines to all people who care for infants, dissemination of guidelines in culturally appropriate ways, and surveillance of SIDS trends and other outcomes associated with implementation of these guidelines.

Central sleep apnea in stable methadone maintenance treatment patients

STUDY OBJECTIVES

Methadone, a long-acting mu-opioid agonist, is an effective treatment for heroin addiction. Our previous data show that 6 of 10 methadone maintenance treatment (MMT) patients had central sleep apnea (CSA). This study aims to confirm these results and to investigate the pathogenesis of the CSA.

METHODS

Twenty-five male and 25 female MMT patients and 20 age-, sex-, and body mass index (BMI)-matched normal subjects were tested with polysomnography, blood toxicology, and ventilatory responses to hypoxia and hypercapnia. Resting cardiorespiratory tests were performed in the MMT group

RESULTS

MMT patients and normal subjects were 35 +/- 9 years old (mean +/- SD), and BMI values were 27 +/- 6 kg/m2 and 27 +/- 5 kg/m2, respectively. Thirty percent of MMT patients had a central apnea index (CAI) > 5, and 20% had a CAI > 10. All normal subjects had a CAI < 1, and no difference was found in obstructive apnea-hypopnea index between the two groups. Methadone blood concentration was the only significant variable (t = 2.33, p = 0.025) associated with CAI and explains 12% of the variance. Awake Pa(CO2), antidepressant use, reduced ventilatory response to hypercapnia, and widened awake alveolar-arterial oxygen pressure gradient together explain a further 17% of the CAI variance.

CONCLUSIONS

Thirty percent of stable MMT patients have CSA, a minority of which can be explained by blood methadone concentration. Other physiologic variables may also play a role in the pathogenesis of CSA in MMT patients, and further research is indicated in this area.

Substance misuse during pregnancy

The use of illicit substances such as cocaine and heroin during pregnancy is common. Anonymous screening of consecutive urine samples testing positive for pregnancy from a UK inner-city clinic demonstrated that approximately 16% of the women had taken one or more illicit substances (Sherwood et al, 1999). The prevalence of drug misuse in the USA appears to be even higher: prospective screening of newborns in a high-risk urban population revealed that 44% of 3010 babies tested positive for opiates, cocaine or cannabis (Ostrea et al, 1992). The aim of this editorial is to emphasise the importance of this topic by describing the unfavourable effects illicit substances can have on both pregnancy and infant outcome. In addition, discussion of the evidence base for current management highlights the need for appropriately designed studies to optimise treatment and reduce morbidity.

Diastolic filling abnormalities by color kinesis in newborns exposed to intrauterine cocaine

Because cocaine crosses the placenta, we prospectively evaluated global and segmental systolic and diastolic cardiac function by color kinesis in clinically asymptomatic newborns who were exposed to cocaine in utero (group 1, n = 82). Their data were compared with normal controls (group 3, n = 87) and newborns exposed to drugs other than cocaine (group 2, n = 108). During left ventricular filling, newborns exposed to cocaine, compared with groups 2 and 3, had significantly (P <.05) higher global fractional area change (%) (76 +/- 10.3 vs 72 +/- 9.4 and 72 +/- 9.1, respectively), regional fractional area changes (%) for the anterior, septal, inferior, and lateral wall, and in the index of asynchrony (at 50% filling 13.2 +/- 5.8 vs 11.3 +/- 4.1 and 11.6 +/- 4.2, respectively). There were no significant differences in systolic function among the 3 groups. Prenatal cocaine exposure in asymptomatic infants leads to higher global and segmental fractional area changes and asynchrony during diastole. The significance and course of these alterations require further investigation.

Heart rate variability in cocaine-exposed newborn infants

BACKGROUND

Infants born to cocaine-using mothers have a 3- to 8-fold increase in sudden infant death syndrome. Its underlying cause, in part, may be attributed to abnormal autonomic function. We proposed to study heart rate variability, reflecting autonomic control of the heart, in cocaine-exposed infants.

METHODS

From 1997 to 2000, we studied 217 asymptomatic, term infants, of whom 68 had intrauterine cocaine exposure (group I). Their data were compared with infants exposed to drugs other than cocaine (group II, n = 77) and no drugs (group III, n = 72). Twenty-four-hour heart rate variability was measured within 72 hours of birth.

RESULTS

Cocaine-exposed infants, as compared with the 2 control groups, had an overall significant decrease (P <.05) in global heart rate variability and a lower standard deviation of all valid N-N intervals in the recording (41.9 +/- 1.4 ms vs 47.6 +/- 1.3 ms and 46.9 +/- 1.3 ms, respectively). Vagal parameters such as high-frequency power and the square root of the mean of the squared differences between adjacent N-N intervals were also lower in newborns with heavy in utero cocaine exposure.

CONCLUSIONS

Decreased heart rate variability was seen in cocaine-exposed infants. Whether low heart rate variability is a marker for increased risk of sudden death in infants (as it is in adults with structural heart disease) is unknown and requires further investigation.

Sudden infant death syndrome, bedsharing, parental weight, and age at death

OBJECTIVE

To assess the role of parental bedsharing in sudden infant death syndrome (SIDS)-like deaths, this study examines the hypothesis that, compared with other SIDS cases, the age distribution of deaths associated with bedsharing should be lower in younger, less vigorous infants.

METHODS

For 84 SIDS cases in Cleveland, Ohio, 1992 to 1996, age at death, maternal weight, and other risk factors for SIDS were compared for cases grouped according to bedsharing status.

RESULTS

Mean ages at death were 9.1 weeks for 30 bedsharing and 12.7 for 54 nonbedsharing cases, counting 10 with missing information as nonbedsharing. Mean pregravid weights of bedsharing mothers exceeded those of nonbedsharing mothers (84.1 vs 67.0 kg). Mean ages at death for nonbedsharing infants, bedsharing infants of smaller mothers, and bedsharing infants of larger mothers were 12.7, 10.3, and 7.6 weeks, respectively. Large maternal size did not affect age at death in the absence of bedsharing.

CONCLUSIONS

By demonstrating that among an urban population at high risk for SIDS, bedsharing is strongly associated with a younger age at death, independent of any other factors, this study provides evidence of a relationship between some SIDS-like deaths and parent-infant bedsharing, particularly if the parent is large.

Tritiated-naloxone binding to brainstem opioid receptors in the sudden infant death syndrome

The sudden infant death syndrome (SIDS) is defined as the sudden death of an infant under 1 year of age that remains unexplained after a thorough case investigation, including a complete autopsy. We hypothesized that SIDS is associated with altered 3H - naloxone binding to opioid receptors in brainstem nuclei related to respiratory and autonomic control. We analyzed 3H - naloxone binding in 21 regions in SIDS and control brainstems using quantitative tissue receptor autoradiography. Three groups were analyzed: SIDS (n = 45); acute controls (n = 14); and a chronic group with oxygenation disorders (n = 15). Opioid binding was heavily concentrated in the caudal nucleus of the solitary tract, nucleus parabrachialis medialis, spinal trigeminal nucleus, inferior olive, and interpeduncular nucleus in all cases analyzed (n = 74). The arcuate nucleus on the ventral medullary surface contained negligible binding in all cases (n = 74), and therefore binding was not measurable at this site. We found no significant differences among the three groups in the age-adjusted mean 3H - naloxone binding in 21 brainstem sites analyzed. The only differences we have found to date between SIDS and acute controls are decreases in 3H - quinuclidinyl benzilate binding to muscarinic cholinergic receptors and in 3H - kainate binding to kainate receptors in the arcuate nucleus in alternate sections of this same data set. The present study suggests that there is not a defect in opioid receptor binding in cardiorespiratory nuclei in SIDS brainstems.

Detection of drug use during pregnancy

Several methods of drug testing are efficacious in identifying and monitoring drug use during pregnancy. Urine screening remains the most commonly used method despite the limited period during which drugs can be detected. Hair has been recognized as a possible alternate test specimen, but wider acceptance of hair testing must await better understanding of drug disposition in hair, answers to the issues relating to interpretation, and the development of less demanding laboratory techniques. Regardless of the matrix used, proper interpretation of the results of drug testing requires familiarity with the sensitivity, specificity, and limitations of the laboratory methodologies employed. Moreover, unconfirmed positive results may actually be false-positives and must be interpreted with caution, particularly if they are the basis for major clinical decisions.

Prenatal cocaine alters normoxic sleep-wake and diaphragmatic EMG patterns in piglets

This study assessed in piglets the effects of prenatal cocaine administration on sleep-wake states (SWS) and respiratory parameters, utilizing diaphragmatic electromyogram (EMGdi) recordings during normoxia before and after hypoxia (0.10 F(I,O2), 10 min). We asked whether the respiratory effects were linked to a specific SWS, and whether there was a difference in respiratory measures between the two normoxic conditions. Unsedated, chronically instrumented 3-9- or 21-31-day-old piglets, representing distinct stages in developmental respiratory control, were used. In pre-hypoxic normoxia, prenatal cocaine enhanced sleep at the expense of wakefulness and increased EMGdi amplitude, slope, and area in both age groups regardless of SWS; after the hypoxia, the respiratory findings persisted in the young group, but disappeared in the older group [corrected]. In the young group and regardless of SWS, interbreath interval (ttot) and expiratory duration (ttot - tEMGdi[duration of EMGdi]) were shorter in the cocaine-exposed than in the unexposed piglets, and ttot, tEMGdi, and (ttot - tEMGdi) decreased from pre- to post-hypoxic normoxia. In the older group, ttot and (ttot - tEMGdi) differed among SWS, but were unaffected by drug treatment; tEMGdi was higher with cocaine exposure in pre-, but not in post-hypoxic normoxia, and two-thirds of the EMGdi measurements during post-hypoxic normoxia exhibited a similar magnitude in the drug-treated and untreated groups regardless of SWS. We conclude that 1) prenatal cocaine alters both SWS and EMGdi, but the EMGdi effects are independent of SWS; and 2) the similar EMGdi patterns in the older group after hypoxia, regardless of drug treatment, suggest that hypoxia and chronic prenatal cocaine might alter EMGdi by similar mechanisms.

Perinatal substance abuse: the impact of reporting infants to child protective services

OBJECTIVE

The purposes of this study were to follow the judicial placement of newborns with positive toxicology screening results and to determine how long such infants remained in foster care, separated from their mothers or other relatives, and the length of court dependency. We also determined the mothers' compliance with court orders, the availability and use of rehabilitative services, factors used by the court to determine the final disposition, and the eventual placement of the infants.

METHODS

The cohort sample consisted of all infants from San Mateo County (CA) born at Stanford University Hospital during a 2-year period whose urine tests in the well-baby nursery were positive for illicit substances. Fifty-three newborns were identified, and their medical records and court documents were matched and reviewed from birth until termination of judicial review (or 5 years). Data were summarized and analyzed by logistic regressions to identify predictors of specific outcomes.

RESULTS

All 53 infants had normal physical examinations and uneventful hospital courses. Their ethnic distribution, with 68% being African-American and 7% being Hispanic, differed from the rest of the nursery population, which was predominantly Hispanic. Twenty-six (46%) of the 53 infants were returned to their mothers within 1 week of birth; 39 (76%) of the infants were reunited with some relative within the first month of life. At 12 months of age, 10 infants (19%) remained in foster care; however, none remained in foster care beyond 18 months. The length of time infants were dependents of the court ranged from 1 month to >5 years; 70% of the cases were "closed" between 6 and 30 months of life. Nine (17%) were dependents of the court for >36 months. Final placement of the infants was 35 (66%) reunited with at least one parent, 9 (17%) in long-term guardianship relationships with other relatives, and 9 (17%) adopted. All of the mothers were ordered to complete a drug rehabilitation program; 24 mothers (44%) fully complied and had repeatedly drug-free urine tests; 2 others (4%) had drug-free urine tests after incomplete participation in drug rehabilitation. Twenty-two (42%) of the mothers never complied with drug rehabilitation. Subsequent drug use was evident in less than half of the mothers during the period of study. Only one mother was reported for child abuse. Characteristics that most strongly predicted failure in family reunification were a history of failed drug rehabilitation, previous involvement of Child Protective Services, or previous removal of a child because of substance abuse.

CONCLUSION

Identifying and reporting newborns exposed to maternal substance abuse during pregnancy can be associated with beneficial changes in the environment of the infants and successful rehabilitation of many mothers. The use of judicial supervision, rehabilitative and supportive services, and long-term involvement of social services without criminal prosecution are key to successful outcome. This study supports the policy and recommendation of the American Academy of Pediatrics and should lessen health professionals' concerns about negative effects of reporting these patients to Child Protective Services.

A case report on drug screening of nail clippings to detect prenatal drug exposure

In a case of a sudden infant death syndrome-related death of a 3-month-old infant, nail clippings were positive for cocaine by gas chromatography-mass spectroscopy analysis that revealed a prenatal exposure to the drug substance. In utero exposure to drugs has been investigated using amniotic fluid, neonatal urine, meconium, and hair samples. Nail analysis offers some advantage over hair analysis because of its continuous growth and persistence after delivery. Nail material is easy to sample in suitable amounts. Currently, the cocaine finding cannot be related to the underlying cause of death. However, this observation indicates that nail analysis may be a new and valuable tool to screen newborns for intrauterine drug exposure. In addition, it can help collect information on the prevalence of possible embryotoxic effects and the link to postnatal manifestations of different dysfunctions in infants who are born by drug abusing mothers.

Drug Use during Pregnancy

Prevention and intervention services for pregnant, drug-using women have often developed prior to gaining empirical data on the antecedents of prenatal drug use. These data are important to address some of the underlying factors of drug use during pregnancy. A review of the literature indentified at least six categories of psychosocial risk factors that have been investigated as relevant to drug use among women, including pregnant women. These factors include: (1) history of childhood sexual abuse, (2) family history of alcohol or drug problems, (3) male partner's alcohol or drug use, (4) current depression, (5) social support, and (6) homelessness or transiency. An examination of these psychosocial risk factors indicates that the existing literature on these factors in drug use is limited by a lack of methodological rigor, resulting in large variations in prevalence rates due to factors such as definition. This paper summarizes the existing literature and methodological iussues regarding the relation between psychosocial risk factors and drug use among women, including pregnant women. It also discusses some of the limitations and issues in assessing prenatal drug use with a particular focus on self-report and urine toxicologies.

Decreased ventilatory response to hypoxia in sedated newborn piglets prenatally exposed to cocaine

OBJECTIVE

Infants exposed to cocaine in utero have been reported to have a higher incidence of apnea and altered ventilatory response to carbon dioxide and hypoxia. We investigated whether in utero cocaine exposure results in greater ventilatory depression during hypoxia in piglets.

METHODS

Cocaine hydrochloride, 1.0 or 2.0 mg/kg given intramuscularly, or saline solution was administered daily to pair-fed pregnant sows during the last month of gestation. Thirteen cocaine-exposed piglets (mean +/- SD: age, 4.4 +/- 1.3 days; weight, 2.10 +/- 0.10 kg) and 15 saline solution-exposed piglets (age, 4.6 +/- 1.1 days; weight, 2.32 +/- 0.42 kg) were studied under chloral hydrate sedation. Minute ventilation (VE), arterial blood pressure (BP), heart rate (HR), oxygen consumption (VO2), and arterial blood gases were measured in room air. During hypoxia (fraction of inspired oxygen = 0.10), the values for VE, BP, and HR were obtained at 1, 5, and 10 minutes, VO2 was calculated during the last 5 minutes, and arterial blood gas samples taken after 10 minutes.

RESULTS

Basal VE did not differ between saline solution- and cocaine-exposed animals. The increase in VE at 1 minute of hypoxia was also similar. However, at 5 and 10 minutes of hypoxia, VE was significantly lower in the cocaine group than in the saline group (6% +/- 9% and 4% +/- 10% vs 15% +/- 13% and 21% +/- 14%; p < 0.02). Mean baseline BP and the initial increase in BP during hypoxia were not different between groups. However, BP remained increased throughout hypoxia only in the saline solution-exposed animals (p < 0.05). Changes in HR, VO2, arterial oxygen tension, and base excess during hypoxia were similar between groups.

CONCLUSIONS

These results show a decrease in the ventilatory response to hypoxia in newborn piglets prenatally exposed to cocaine. This change is most likely to be centrally mediated because the initial hypoxic hyperventilation was not modified by the intrauterine cocaine exposure. This decrease in ventilation cannot be explained by changes in metabolic rate or in cardiovascular or acid-base status.

Sudden infant death syndrome — a ‘diagnosis’ in search of a disease

Although Sudden Infant Death Syndrome (SIDS) is the major cause of death in infants aged between 1 week and 1 year in Western countries, it is one of the most enigmatic conditions encountered in paediatric forensic practice. SIDS has been recognized since Biblical times, and yet the definition continues to be debated and the aetiology remains obscure. In addition, there are no accepted pathognomonic features at post-mortem and the diagnosis is still one of exclusion. Emery once asked whether the term 'SIDS' is in reality more of a 'diagnostic dustbin' into which are placed a variety of unrelated entities.(1) To a certain extent this is true, as it is now recognized that a range of disorders can result in the sudden and unexpected death of an infant in a cot. It is also likely that the aetiology of SIDS is heterogeneous and that the term SIDS is not so much a diagnosis but a term covering a variety of mechanisms which result in a common lethal outcome. There are a number of controversies in the SIDS field which complicate the use of the term and which confound the assessment of causes and mechanisms of sudden infant death.