Showing papers on "Sudden infant death syndrome published in 2002"

UWB radars in medicine

Abstract: Applied research on biomedical applications of UWB radar is targeted to the identification of the possible new devices made possible by the technology, to the design and development of those devices, and to the clinical testing of the systems obtained. Applications can be divided into two main sectors according to the frequency range used. For the conventional UWB radar microwave region: cardiac biomechanics assessment; chest movements assessment OSA (obstructive sleep apnoea) monitors; soft-tissue biomechanics research; heart imaging ("Holter type" echocardiography); chest imaging. Together with systems for: cardiac monitoring; respiratory monitoring; SIDS (sudden infant death syndrome) monitor; vocal tract studying. If an IR laser diode is used as the antenna, a more common radar is obtained (actually a hybrid between a narrow band and a wide band radar) which emits a short packet of electromagnetic waves whose echoes are sampled using conventional UWB receiver equipped with a PIN photodiode. Possibilities include: non-invasive biochemical study of soft tissues, non-invasive study of metabolic processes, and IR spectral imaging.

Deaths: leading causes for 2000.

Abstract: Objectives This report presents final 2000 data on the 10 leading causes of death in the United States by age, race, sex, and Hispanic origin. Leading causes of infant, neonatal, and postneonatal death are also presented. This report supplements the annual report of final mortality statistics. Methods Data in this report are based on information from all death certificates filed in the 50 States and the District of Columbia in 2000. Causes of death classified by the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) are ranked according to the number of deaths assigned to rankable causes. Results In 2000 the 10 leading causes of death were (in rank order) Diseases of heart; Malignant neoplasms; Cerebrovascular diseases; Chronic lower respiratory diseases; Accidents (unintentional injuries); Diabetes mellitus; Influenza and pneumonia; Alzheimer's disease; Nephritis, nephrotic syndrome and nephrosis; and Septicemia and accounted for nearly 80 percent of all deaths occurring in the United States. Differences in the rankings are evidently by age, sex, race, and Hispanic origin. Leading causes of infant death for 2000 were (in rank order) Congenital malformations, deformations and chromosomal abnormalities; Disorders related to short gestation and low birthweight, not elsewhere classified; Sudden infant death syndrome; Newborn affected by maternal complications of pregnancy; Newborn affected by complications of placenta, cord and membranes; Respiratory distress of newborn; Accidents (unintentional injuries); Bacterial sepsis of newborn; Diseases of the circulatory system; and Intrauterine hypoxia and birth asphyxia. Important variation in the leading causes of infant death is noted for the neonatal and postneonatal periods.

The triple risk hypotheses in sudden infant death syndrome.

Abstract: Sudden infant death syndrome (SIDS) victims were regarded as normal as a matter of definition (Beckwith 1970) until 1952 when Kinney and colleagues argued for elimination of the clause, "unexpected by history." They argued that "not all SIDS victims were normal," and referred to their hypothesis that SIDS results from brain abnormalities, which they postulated "to originate in utero and lead to sudden death during a vulnerable postnatal period." Bergman (1970) argued that SIDS did not depend on any "single characteristic that ordains a infant for death," but on an interaction of risk factors with variable probabilities. Wedgwood (1972) agreed and grouped risk factors into the first "triple risk hypothesis" consisting of general vulnerability, age-specific risks, and precipitating factors. Raring (1975), based on a bell-shaped curve of age of death (log-transformed), concluded that SIDS was a random process with multifactorial causation. Rognum and Saugstad (1993) developed a "fatal triangle" in 1993, with groupings similar to those of Wedgwood, but included mucosal immunity under a vulnerable developmental stage of the infant. Filiano and Kinney (1994) presented the best known triple risk hypothesis and emphasized prenatal injury of the brainstem. They added a qualifier, "in at least a subset of SIDS," but, the National Institute of Child Health and Development SIDS Strategic Plan 2000, quoting Kinney's work, states unequivocally that "SIDS is a developmental disorder. Its origins are during fetal development." Except for the emphasis on prenatal origin, all 3 triple risk hypotheses are similar. Interest in the brainstem of SIDS victims began with Naeye's 1976 report of astrogliosis in 50% of all victims. He concluded that these changes were caused by hypoxia and were not the cause of SIDS. He noted an absence of astrogliosis in some older SIDS victims, compatible with a single, terminal episode of hypoxia without previous hypoxic episodes, prenatal or postnatal. Kinney and colleagues (1983) reported gliosis in 22% of their SIDS victims. Subsequently, they instituted studies of neurotransmitter systems in the brainstem, particularly the muscarinic (1995) and serotenergic systems (2001). The major issue is when did the brainstem abnormalities, astrogliosis, or neurotransmitter changes occur and whether either is specific to SIDS. There is no published method known to us of determining the time of origin of these markers except that the injury causing astrogliosis must have occurred at least 4 days before death (Del Bigio and Becker, 1994). Because the changes in neurotransmitter systems found in the arcuate nucleus in SIDS victims were also found in the chronic controls with known hypoxia, specificity of these markers for SIDS has not been established. It seems likely that the "acute control" group of Kinney et al (1995) died too quickly to develop gliosis or severe depletion of the neurotransmitter systems. We can conclude that the acute controls had no previous episodes of severe hypoxia, unlike SIDS or their "chronic controls." Although the average muscarinic cholinergic receptor level in the SIDS victim was significantly less than in the acute controls, the difference was only 27%, and only 21 of 41 SIDS victims had values below the mean of the acute controls. The study of the medullary serotonergic network by Kinney et al (2001) revealed greater reductions in the SIDS victims than in acute controls, but the questions of cause versus effect of the abnormalities, and whether they occurred prenatally or postnatally, remain unanswered. Hypoplasia of the arcuate nucleus was stated to occur in 5% of their SIDS cases by Kinney et al (2001), but this is a "primary developmental defect" according to Matturri et al (2002) with a larger series, many of whom were stillbirths. These cases should not be included under the rubric of SIDS, by definition. There are difficulties with Filiano and Kinney's (1994) explanation of the age at death distribution of SIDS. They postulate that the period between 1 and 6 months represents an unstable time for virtually all physiologic systems. However, this period demonstrates much less instability than does the neonatal period, when most deaths from congenital defects and severe maternal anemia occur. We present data for infants born to mothers who were likely to have suffered severe anemia as a consequence of placenta previa, abruptio placentae, and excessive bleeding during pregnancy; these infants presumably are at increased risk of hypoxia and brainstem injury. The total neonatal mortality rate in these 3 groups of infants is 4 times greater than the respective postneonatal mortality, and in the postneonatal period the non-SIDS mortality rate is between 14 and 22 times greater than the postneonatal SIDS rate in these 3 groups. A preponderance of deaths in the neonatal period is also found for congenital anomalies, a category that logically should include infants who experienced prenatal hypoxia or ischemia; this distribution of age of death is very different from that for SIDS, which mostly spares the first month and peaks between 2 and 3 months of age. Finally, evidence inconsistent with prenatal injury as a frequent cause of SIDS comes from prospective studies of ventilatory control in neonates who subsequently died of SIDS; no significant respiratory abnormalities in these infants have been found (Waggener et al 1990; Schectman et al 1991). We conclude that none of the triple risk hypotheses presented so far have significantly improved our understanding of the cause of SIDS. Bergman's and Raring's concepts of multifactorial causation with interaction of risk factors with variable probabilities is less restrictive and more in keeping with the large number of demonstrated risk factors and their varying prevalence. If prenatal hypoxic damage of the brainstem occurred, it seems likely that the infant so afflicted would be at risk for SIDS, but it is even more likely that their death would occur in the neonatal period, as we have demonstrated in infants who have known maternal risk factors that involve severe anemia. This is in contrast to the delay until the postneonatal period of most SIDS deaths. A categorical statement that the origin of SIDS is prenatal is unwarranted by the evidence. Brainstem abnormalities have not been shown to cause SIDS, but are more likely a nonspecific effect of hypoxia.

Can Child Deaths Be Prevented? The Arizona Child Fatality Review Program Experience

Abstract: Objective. To determine the causes and preventability of child deaths; to assess the accuracy of death certificate information; and to assess the number of child abuse deaths that are misdiagnosed as deaths attributable to natural or accidental causes. Methods. Analysis of deaths of children Results. From 1995–1999, local multidisciplinary child fatality review teams (CFRTs) have reviewed 95% of all deaths of children Most deaths attributable to medical conditions occurred in the first year of life. Prematurity was the most common medical condition (1036 deaths) followed by congenital anomalies (662 deaths) and infectious diseases (470 deaths). Some of the reasons why CFRTs believed a medical death was preventable included inadequate emergency medical services, poor continuity of care, and delay in seeking care because of lack of health insurance. There were 4 deaths resulting from infections that were vaccine-preventable. There were 263 deaths attributable to sudden infant death syndrome. Only 38 of these infants were found lying on their back; 35 were found lying on their side. The death rate from sudden infant death syndrome decreased from 1.1 per 1000 infants From 1995–1999, 317 Arizona children died from gun shot wounds. Most of these deaths were homicides (175) or suicides (109). All suicide deaths occurred in children >9 years old, and 77% of these children were >14 years old. The typical suicide victim was male (83%) and used a gun (70%) to kill himself. After review by the CFRTs, it was determined that 5 of the 67 child abuse deaths were misdiagnosed as attributable to natural or accidental causes on the death certificate. In 3 of these 5 cases, the child was in a persistent vegetative state and died many years after the episode of child abuse. Although inaction or inappropriate action by Child Protective Services (CPS) is often thought to be the cause of child abuse deaths, the ACFRP determined that in 79% of child abuse deaths, there had been no previous CPS involvement with the child’s family. Although 61% of child abuse deaths were considered to be preventable, much of the responsibility for preventing these deaths rests with community members (eg, relatives, neighbors) who were aware of the abuse but failed to report the family to CPS. The CFRTs, who had received training in the proper completion of death certificates, reported that the cause of death was incorrect on 13% of all death certificates and in 16 cases, the CFRTs disagreed with the medical examiner on the manner of death (eg, natural, accidental, undetermined). Because CFRTs have access to additional information that may not have been available to the physician who completes a child’s death certificate, CFRTs may be able to more accurately determine the cause and manner of death than the physician who completed the death certificate. Conclusions. Arizona’s child death rate is above the national average (82.16/100 000), but the ACFRP determined that many of these deaths could have been prevented by using known prevention strategies (eg, child safety restraints, pool fencing). Most child mortality data are based on death certificate information that often is incorrect and cannot be used to assess preventability. Although most states have child fatality review programs that review suspected child abuse deaths,

Risk Factors for Sudden Infant Death Syndrome Among Northern Plains Indians

Abstract: Results The proportions of case and control infants who were usually placed prone to sleep (15.2% and 13.6%, respectively), who shared a bed with parents (59.4% and 55.4%), or whose mothers smoked during pregnancy (69.7% and 54.6%) were similar. However, mothers of 72.7% of case infants and 45.5% of control infants engaged in binge drinking during pregnancy. Conditional logistic regression revealed significant associations between SIDS and 2 or more layers of clothing on the infant (adjusted odds ratio [aOR], 6.2; 95% confidence interval [CI], 1.4-26.5), any visits by a public health nurse (aOR, 0.2; 95% CI, 0.1-0.8), periconceptional maternal alcohol use (aOR, 6.2; 95% CI, 1.6-23.3), and maternal first-trimester binge drinking (aOR, 8.2; 95% CI, 1.9-35.3). Conclusions Public health nurse visits, maternal alcohol use during the periconceptional period and first trimester, and layers of clothing are important risk factors for SIDS among Northern Plains Indians. Strengthening public health nurse visiting programs and programs to reduce alcohol consumption among women of childbearing age could potentially reduce the high rate of SIDS. JAMA. 2002;288:2717-2723 www.jama.com

Chemosensitive serotonergic neurons are closely associated with large medullary arteries

Abstract: We have previously shown that serotonergic neurons of the medulla are strongly stimulated by an increase in CO2, suggesting that they are central respiratory chemoreceptors. Here we used confocal imaging and electron microscopy to show that neurons immunoreactive for tryptophan hydroxylase (TpOH) are tightly apposed to large arteries in the rat medulla. We used patch-clamp recordings from brain slices to confirm that neurons with this anatomical specialization are chemosensitive. Serotonergic neurons are ideally situated for sensing arterial blood CO2, and may help maintain pH homeostasis via wide-ranging effects on brain function. The results reported here support a recent proposal that sudden infant death syndrome (SIDS) results from a developmental abnormality of medullary serotonergic neurons1.

Where do children with complex chronic conditions die? Patterns in Washington State, 1980-1998.

Abstract: Objective Little is known about factors that influence whether children with chronic conditions die at home. We sought to test whether deaths attributable to underlying complex chronic conditions (CCCs) were increasingly occurring at home and to determine what features were associated with home deaths. Design A retrospective case series was conducted of all deaths that occurred to children age 0 to 18 years in Washington state from 1980 to 1998 using death certificate data, augmented with 1990 US Census data regarding median household income by zip code in 1989, to determine the site of death. Results Of the 31 455 deaths identified in infants, children, and adults younger than 25 years, 52% occurred in the hospital, 17.2% occurred at home, 8.5% occurred in the emergency department or during transportation, 0.4% occurred in nursing homes, and 21.7% occurred at other sites. Among children who died as a result of some form of CCC (excluding injury, sudden infant death syndrome, and non-CCC medical conditions), the percentage of cases younger than 1 year who died at home rose slightly from 7.8% in 1980 to 11.6% in 1998, whereas the percentage of older children and young adults who had a CCC and died at home rose substantially from 21% in 1980 to 43% in 1998. Children who had lived in more affluent neighborhoods were more likely to have died at home. Using leukemia-related deaths as a benchmark, deaths as a result of congenital, genetic, neuromuscular, and metabolic conditions and other forms of cancer all were more likely to have occurred at home. Significant variation in the likelihood of home death, not explained by the individual attributes of the cases, also existed across the 39 counties in Washington state. Conclusions Children who die with underlying CCCs increasingly do so at home. Age at death, specific condition, local area affluence, and the location of home all influence the likelihood of home death. These findings warrant additional study, as they have implications for how we envision pediatric palliative care, hospice, and other supportive services for the future.

The Contribution of Prone Sleeping Position to the Racial Disparity in Sudden Infant Death Syndrome: The Chicago Infant Mortality Study

Abstract: Background. Rates of sudden infant death syndrome (SIDS) are over twice as high among African Americans compared with Caucasians. Little is known, however, about the relationship between prone sleeping, other sleep environment factors, and the risk of SIDS in the United States and how differences in risk factors may account for disparities in mortality. Objective. To assess the contribution of prone sleeping position and other potential risk factors to SIDS risk in a primarily high-risk, urban African American population. Design, Setting, and Population. Case-control study consisting of 260 infants ages birth to 1 year who died of SIDS between November 1993 and April 1996. The control group consists of an equal number of infants matched on race, age, and birth weight. Prospectively collected data from the death scene investigation and a follow-up home interview for case infants were compared with equivalent questions for living control participants to identify risk factors for SIDS. Main Outcome Measures. Risk of SIDS related to prone sleeping position adjusting for potential confounding variables and other risk factors for SIDS, and comparisons by race-ethnicity. Results. Three quarters of the SIDS infants were African American. There was more than a twofold increased risk of SIDS associated with being placed prone for last sleep compared with the nonprone positions (odds ratio [OR]: 2.4; 95% confidence interval [CI]: 1.6–3.7). This OR increased after adjusting for potential confounding variables and other sleep environment factors (OR: 4.0; 95% CI: 1.8–8.8). Differences were found for African Americans compared with others (OR: 1.8; 95% CI: 1.2–2.6 and OR: 10.3, 95% CI: 10.3 [3.2–33.8, respectively]). The population attributable risk was 31%. Fewer case mothers (46%) than control mothers (64%) reported being advised about sleep position in the hospital after delivery. Of those advised, a similar proportion of case mothers as control mothers were incorrectly told or recalled being told to use the prone position, but prone was recommended in a higher proportion of black mothers (cases and controls combined) compared with nonblack mothers. Conclusions. Prone sleeping was found to be a significant risk factor for SIDS in this primarily African American urban sample, and approximately one third of the SIDS deaths could be attributed to this factor. Greater and more effective educational outreach must be extended to African American families and the health personnel serving them to reduce prone prevalence during sleep, which appears, in part, to contribute to the higher rates of SIDS among African American infants.

Infant mortality statistics from the 1999 period linked birth/infant death data set.

Abstract: Objectives—This report presents 1999 period infant mortality statistics from the linked birth/infant death data set (linked file) by a variety of maternal and infant characteristics. Methods—Descriptive tabulations of data are presented. Results—In general, mortality rates were lowest for infants born to Chinese and Japanese mothers (2.9 and 3.4 per 1,000, respectively). Infants of Cuban, Central and South American, Mexican, and nonHispanic white mothers had low rates, while rates were higher for infants of Puerto Rican and highest for non-Hispanic black mothers (13.9). Filipino mothers also had low rates. Rates were high for infants of Hawaiian and American Indian mothers. Infant mortality rates were higher for those infants whose mothers had no prenatal care, were teenagers, had 9–11 years of education, were unmarried, or smoked during pregnancy. Infant mortality was also higher for male infants, multiple births, and infants born preterm or at low birthweight. The three leading causes of infant death—Congenital malformations, low birthweight, and Sudden infant death syndrome (SIDS)–taken together accounted for 45 percent all infant deaths in the United States in 1999. Cause-specific mortality rates varied considerably by race and Hispanic origin. For infants of black mothers, the infant mortality rate for low

Infant mortality statistics from the 2000 period linked birth/infant death data set.

Abstract: OBJECTIVES This report presents the 2000 period infant mortality statistics from the linked birth/infant death data set (linked file) by a variety of maternal and infant characteristics. METHODS Descriptive tabulations of data are presented and interpreted. RESULTS Infant mortality rates ranged from 3.5 per 1,000 live births for Chinese mothers to 13.5 for black mothers. Among Hispanics, rates ranged from 4.5 for Cuban mothers to 8.2 for Puerto Rican mothers. Infant mortality rates were higher for those infants whose mothers had no prenatal care, were teenagers, had 9-11 years of education, were unmarried, or smoked during pregnancy. Infant mortality was also higher for male infants, multiple births, and infants born preterm or at low birthweight. The three leading causes of infant death--Congenital malformations, low birthweight, and Sudden infant death syndrome (SIDS)--taken together accounted for 45 percent of all infant deaths in the United States in 2000. Cause-specific mortality rates varied considerably by race and Hispanic origin. For infants of black mothers, the infant mortality rate for low birthweight was nearly four times that for white mothers. For infants of black and American Indian mothers, the SIDS rates were 2.4 and 2.3 times that for non-Hispanic white mothers.

Alteration of serotonergic receptors in the brain stems of human patients with respiratory disorders.

Abstract: We compared the developmental changes of 5-hydroxytryptamine (5-HT) 1 A and 5-HT2 A receptor immunoreactivity in the nuclei in relation to the cardiorespiratory or autonomic function in the human brain stem in sudden infant death syndrome (SIDS) and congenital central hypoventilation syndrome (CCHS) patients and age-matched controls by means of immunohistochemical methods. There were significant decreases in 5-HT1 A and 5-HT2 A receptor immunoreactivity in the dorsal nucleus of the vagus, solitary nucleus and ventrolateral medulla in the medulla oblongata, and significant increases in the periaqueductal gray matter (PAG) of the midbrain in SIDS victims, but there were no significant differences between those in CCHS patients and controls. The decreased immunoreactivity of the receptors in the medulla oblongata was accompanied by brain stem gliosis. Therefore, the decreases in the receptors may be secondary to chronic hypoxia or repeated ischemia, but may be causally related to some impairment of the developing cardiorespiratory neuronal system. As 5-HT1 A and 5-HT2 A receptors were the most abundant in the fetal period and then decreased with subsequent development, the increases in 5-HT1 A and 5-HT2 A receptor immunoreactivity in PAG may reflect delayed neuronal maturation, but may also reflect compensatory changes in response to hypofunctioning serotonergic neurons in the medulla oblongata in SIDS. There was no abnormal expression of 5-HT1 A and 5-HT2 A receptors in CCHS brain stems, and so the pathophysiology seems to be different between SIDS and CCHS patients.

Couple distress after sudden infant or perinatal death: a 30-month follow up.

Abstract: Objective: To examine, using a 30-month prospective study, patterns of anxiety, depression and alcohol use in couples following stillbirth, neonatal death or sudden infant death syndrome. Methodology: One hundred and thirty-eight bereaved and 156 non-bereaved couples completed standardized interviews at 2, 8, 15 and 30 months post-loss. Results: At all interviews, bereaved couples were significantly more likely than non-bereaved couples to have at least one distressed partner. Rarely were both partners distressed in either group. For bereaved couples, 'mother only' distress declined from 21% to 10% during the study. 'Father only' distress ranged from 7% to 15%, peaking at 30 months. Bereaved mothers who were distressed at 2 months reported significantly lower marital satisfaction at 30 months. Conclusions: At the couple level, the experience of a baby's death is multifaceted. Gender differences are common and partners' needs may change over time. Early recognition of these differences may facilitate longer-term adjustment for both partners.

Prenatal nicotine exposure blunts the cardiorespiratory response to hypoxia in lambs.

Abstract: Because smoking during pregnancy is a major risk factor for late fetal death and the sudden infant death syndrome, we investigated cardiorespiratory defense mechanisms to hypoxia in 7 prenatally nicotine-exposed (N) lambs (approximate maternal dose: 0.5 mg/kg/day) and 11 control (C) lambs all at an average age of 5 days. The ventilatory response to 10% oxygen (hyperpnea) was significantly attenuated during quiet sleep in N lambs compared with C lambs and in N lambs aroused from sleep later compared with C lambs (161 +/- 90 versus 75 +/- 66 seconds, p < 0.05). The ventilatory response to hypoxia was similar in the two groups during wakefulness (W), whereas the heart rate response (tachycardia) was significantly lower in N lambs compared with C lambs during both activity states. The ventilatory response to hyperoxia was significantly lower in N lambs compared with C lambs during both activity states. Transition from W to quiet sleep was associated with a significant decrease in ventilation in C lambs but not in N lambs. In conclusion, prenatal nicotine exposure, at a dose comparable with moderate smoking, blunts major elements of the cardiorespiratory defense to hypoxia, i.e., the heart rate and ventilatory and arousal responses, and abolishes the normal decrease in ventilation during sleep compared with W.

Infant sleep placement after the back to sleep campaign.

Abstract: Objectives. The Back to Sleep campaign has been credited with recent declines in the incidence of sudden infant death syndrome. Using survey data for the 1996–1998 birth cohorts, this epidemiologic study examines infant sleep position in a large, population-based sample. Data and Methods. Data concerning infant sleep position are drawn from the 1996–1998 Pregnancy Risk Assessment Monitoring System for 15 states. Weighted multiple logistic regression analysis is used to examine correlates of infant sleep position. Results. The prevalence of prone infant sleeping significantly declined between 1996 and 1998 (adjusted odds ratio [AOR] = 0.70; 95% confidence interval [CI] = [0.63, 0.78]). African Americans were more likely than non-Hispanic whites to sleep prone, (AOR = 1.45; 95% CI = 1.33,1.59), and were less likely to sleep supine (AOR = 0.52; 95% CI = 0.48, 0.57). Hispanic/Latinos were less likely overall than non-Hispanic whites to sleep prone (AOR = 0.81; 95% CI = 0.69, 0.95), but were also less likely to sleep supine (AOR = 0.78; 95% CI = 0.69, 0.87). Adherence to sleep position recommended by the American Academy of Pediatrics increased sharply among Hispanic/Latino infants. Very low birth weight infants and infants in larger families were less likely to sleep in the recommended supine position. Infants born between 1001 and 1500 g (AOR = 0.67; 95% CI = 0.57, 0.79), and extremely low birth weight infants between 500 and 1000 g (AOR = 0.57; 95% CI = 0.45, 0.72) were especially unlikely to sleep supine. Infants in households with more than 3 other children (AOR = 1.72; 95% CI = 1.08, 2.74) were more likely to sleep prone. Conclusions. The prevalence of supine infant sleep increased between 1996 and 1998. Low adherence to sleep position recommendations of the American Academy of Pediatrics among African Americans, very low birth weight infants, and infants in large families remain public health concerns.

Prevalence of retinal hemorrhages and child abuse in children who present with an apparent life-threatening event

Abstract: Objective Child abuse (CA) can present with a spectrum of signs and symptoms. Apparent life-threatening events (ALTEs) may be a subtle presentation of CA. Retinal hemorrhages (RHs) are a well-described finding in some patients with CA. We hypothesized that screening children who present with a chief complaint of an ALTE for RH would detect an otherwise occult presentation of CA. Methods Children who were younger than 24 months of age and presented to the emergency department between March 1, 1997, and February 28, 1999, with signs and symptoms consistent with the National Institutes of Health's definition of an ALTE were studied prospectively. Children were excluded when it was readily apparent on presentation that the child was a victim of CA. Demographic data, a complete blood count with differential, venous blood gas, carboxyhemoglobin level, and urine toxicological screen were collected. A pediatric ophthalmologist performed a dilated funduscopic examination; patients who were found to have RH underwent a noncontrast computerized tomographic scan of the head and skeletal survey to evaluate for occult injury. Evaluations by social services or Children, Youth and Families, the results of all diagnostic tests obtained, and the final discharge diagnosis were recorded. Medical records of all patients were reviewed at 1 year; subsequent visits, hospitalizations, and evaluations by social services or Children, Youth and Families were recorded. Results A total of 128 patients presented to the emergency department with an ALTE during the study period. No patients were excluded. Mean age was 2.1 months (median: 1.27; range: 0.07-16.0; standard deviation: 2.1). Fifty-seven (44.5%) were boys; 86 (67.2%) were white, and 36 (27.9%) were black. A total of 26 (20.3%) of 128 patients had a history of an ALTE, 4 (3.4%) of 117 had a family history of an ALTE, and 15 (12.8%) of 117 had a family history of sudden infant death syndrome. Dilated funduscopic examination was performed on 73 (57.0%) of 128 patients; RH was detected in 1 patient (1.4%). Four children, including the patient with RH, underwent an evaluation for suspected abuse; 3 (2.3%) of 128 were determined to have been abused. Conclusions RH was detected in 1 (1.4%) of 73 patients in our population of infants with ALTEs and 1 of 3 patients who were victims of CA and presented with an ALTE. CA was detected in 2.3% of patients who presented with an ALTE. The diagnosis of CA should be seriously considered in patients who present with an ALTE. The evaluation of ALTEs should include funduscopic examination as ALTEs and RHs are associated with CA.

Programming of sympathoadrenal function

Abstract: Environmental exposures at crucial points in development permanently alter sympathoadrenal function in mammals. The sympathetic innervation of peripheral tissues and the responsiveness of sympathetic nerves and adrenal medulla to standard stimuli are susceptible to modification by exposures in early life, such as environmental temperature, nutrition and stress. Because the sympathetic nervous system is composed of multiple, function-specific subunits, programming of sympathetic functions occurs on a regional rather than a global basis and can aid development of a phenotype adapted to the local environment. Under some circumstances, however, adaptations in early life might prove maladaptive in adulthood and, as a consequence, might provide a basis for developmental origins of pediatric and adult disease, such as sudden infant death syndrome and obesity.

Sleeping pad, bedding and bumpers to improve respiratory efficiency and environmental temperature of an infant and reduce the risks of sudden infant death syndrome (SIDS) and asphyxiation

Abstract: Rebreathing carbon dioxide and overheating of the infant are contributing causes of Sudden Infant Death Syndrome (SIDS) and asphyxiation. The characteristics of conventional crib mattresses, bedding and bumper pads contribute to rebreathing of carbon dioxide and overheating of the infant and may be contributing environmental causes of SIDS, asphyxiation, apnea syndromes and hypoventilation. The present invention consists of improved sleeping pads, beddings and bumper pads which reduce rebreathing of carbon dioxide and overheating and provide increased crib ventilation to stimulate breathing.

Breast feeding and the sudden infant death syndrome in Scandinavia, 1992–95

Abstract: Aims: To assess the effects of breast feeding habits on sudden infant death syndrome (SIDS). Methods: The analyses are based on data from the Nordic Epidemiological SIDS Study, a case–control study in which parents of SIDS victims in the Scandinavian countries between 1 September 1992 and 31 August 1995 were invited to participate, each with parents of four matched controls. The odds ratios presented were computed by conditional logistic regression analysis. Results: After adjustment for smoking during pregnancy, paternal employment, sleeping position, and age of the infant, the adjusted odds ratio (95% CI) was 5.1 (2.3 to 11.2) if the infant was exclusively breast fed for less than four weeks, 3.7 (1.6 to 8.4) for 4–7 weeks, 1.6 (0.7 to 3.6) for 8–11 weeks, and 2.8 (1.2 to 6.8) for 12–15 weeks, with exclusive breast feeding over 16 weeks as the reference. Mixed feeding in the first week post partum did not increase the risk. Conclusions: The study is supportive of a weak relation between breast feeding and SIDS reduction.

β2 nicotinic acetylcholine receptor subunit modulates protective responses to stress: A receptor basis for sleep-disordered breathing after nicotine exposure

Abstract: Nicotine exposure diminishes the protective breathing and arousal responses to stress (hypoxia). By exacerbating sleep-disordered breathing, this disturbance could underpin the well established association between smoking and the increased risk of sudden infant death syndrome. We show here that the protective responses to stress during sleep are partially regulated by particular nicotinic acetylcholine receptors (nAChRs). We compared responses of sleeping wild-type and mutant mice lacking the β2 subunit of the nAChR to episodic hypoxia. Arousal from sleep was diminished, and breathing drives accentuated in mutant mice indicating that these protective responses are partially regulated by β2-containing nAChRs. Brief exposure to nicotine significantly reduced breathing drives in sleeping wild-type mice, but had no effect in mutants. We propose that nicotine impairs breathing (and possibly arousal) responses to stress by disrupting functions normally regulated by β2-containing, high-affinity nAChRs.

Used infant mattresses and sudden infant death syndrome in Scotland: case-control study.

Abstract: Objective: To examine the proposition that a used infant mattress is associated with an increased risk of sudden infant death syndrome. Design: Case-control study. Setting: Scotland (population 5.1 million, with about 53 000 births a year). Participants: 131 infants who died of sudden infant death syndrome between 1 January 1996 and 31 May 2000 and 278 age, season, and obstetric unit matched control infants. Main outcome measures: Routine use of an infant mattress previously used by another child and place of last sleep. Results: Routine use of an infant mattress previously used by another child was significantly associated with an increased risk of sudden infant death syndrome (multivariate odds ratio 3.07, 95% confidence interval 1.51 to 6.22). Use of a used infant mattress for last sleep was also associated with increased risk (6.10, 2.31 to 16.12). The association was significantly stronger if the mattress was from another home (4.78, 2.08 to 11.0) than if it was from the same home (1.64, 0.64 to 4.2). Conclusion: A valid significant association exists between use of a used infant mattress and an increased risk of sudden infant death syndrome, particularly if the mattress is from another home. Insufficient evidence is available to judge whether this relation is cause and effect. #### What is already known about this topic What is already known about this topic The major risk factors for sudden infant death syndrome are sleeping prone and parental smoking One study has suggested that the syndrome is associated with sleeping on an infant mattress previously used by another child #### What this study adds What this study adds New case-control data show that the association between a previously used infant mattress and sudden infant death syndrome is valid When source of used mattress is categorised, the association is significant only if the mattress is from another home Insufficient evidence is available to judge whether this is a cause and effect relation

Trends in postneonatal aspiration deaths and reclassification of sudden infant death syndrome: Impact of the back to Sleep program

Abstract: Objective. The introduction of the “Back to Sleep” campaign for the prevention of sudden infant death syndrome (SIDS) brought with it concern that there might be an increase in the incidence of aspiration-related deaths. The objective of this analysis was to describe the trends in postneonatal mortality and proportionate mortality ratios for the United States for the years 1991 to 1996 for aspiration-related deaths and other causes to which a SIDS death could conceivably be reclassified. Methods. Linked birth and infant death vital statistic files for the United States were used for the years 1991, 1995, and 1996. US Vital Statistic Mortality files for the years 1992, 1993, and 1994 were used because of the absence of linked files for those years. Results. The overall postneonatal mortality rate between 1991 and 1996 declined 21.9%, whereas the SIDS rate declined 38.9%. The proportion of the postneonatal mortality (PNPMR) contributed by SIDS declined from 37.1% in 1991 to 28.8% in 1996. There was no significant increase in the PNPMR for aspiration, asphyxia, or respiratory failure. There was, however, a significant increase in the PNPMR for suffocation in bed or cradle from 0.9 to 1.3. Conclusions. These data show no evidence of an increased risk of death from aspiration as a result of the “Back to Sleep” program. Although there has been an increase in the proportion of postneonatal mortality attributable to suffocation, this represents a very small proportion of postneonatal mortality and thus potentially a very small number of SIDS deaths reclassified as suffocation.

Spontaneous Arousals in Supine Infants While Swaddled and Unswaddled During Rapid Eye Movement and Quiet Sleep

Abstract: Objective. Supine sleep is recommended for infants to decrease the risk of sudden infant death syndrome, but many parents report that their infants seem uncomfortable supine. Many cultures swaddle infants for sleep in the supine position. Swaddled infants are said to “sleep better”; presumably they sleep longer or with fewer arousals. However, there have been no studies of the effect of swaddling on spontaneous arousals during sleep. Arousal is initiated in brainstem centers and manifests as a sequence of reflexes: from sighs to startles and then to thrashing movements. Such “brainstem arousals” may progress to full arousal, but most do not. Methods. Twenty-six healthy infants, aged 80 ± 7 days, were studied during normal nap times. Swaddled (cotton spandex swaddle) and unswaddled trials were alternated for each infant. Sleep state (rapid eye movement [REM] or quiet sleep [QS]) was determined by behavioral criteria (breathing pattern, eye movements) and electroencephalogram/electrooculogram (10 infants). Respitrace, submental and biceps electromyogram, and video recording were used to detect startles and sighs (augmented breaths). Full arousals were classified by eye opening and/or crying. Frequencies of sighs, startles, and full arousals per hour were calculated. Progression of events was calculated as percentages in each sleep state, as was duration of sleep state. Results. Swaddling decreased startles in QS and REM, full arousal in QS, and progression of startle to arousal in QS. It resulted in shorter arousal duration during REM sleep and more REM sleep. Conclusions. Swaddling has a significant inhibitory effect on progression of arousals from brainstem to full arousals involving the cortex in QS. Swaddling decreases spontaneous arousals in QS and increases the duration of REM sleep, perhaps by helping infants return to sleep spontaneously, which may limit parental intervention. For these reasons, a safe form of swaddling that allows hip flexion/abduction and chest wall excursion may help parents keep their infants in the supine sleep position and thereby prevent the sudden infant death syndrome risks associated with the prone sleep position.

The Brugada syndrome

Abstract: In 1992 a syndrome consisting of syncope episodes and/or sudden death in patients with a structurally normal heart and a characteristic electrocardiogram (ECG) displaying a pattern resembling right bundle branch block with ST segment elevation in leads V1 to V3 was described. The disease is genetically determined with an autosomal dominant pattern of transmission in 50% of the familial cases. Several different mutations have been identified affecting the structure and the function of the sodium channel gene SCN5A. These mutations result in loss of function of the sodium channel. The syndrome appears ubiquitous. The incidence of the disease is difficult to estimate worldwide, but it may cause 4 to 10 sudden deaths per 10,000 inhabitants per year in areas like Thailand and Laos. In these countries, the disease represents the most frequent cause of natural death in young adults. It is estimated that 20 to 50% of sudden deaths in patients with a normal heart result from this syndrome. The disease has been linked to the sudden infant death syndrome and to the sudden unexpected death syndrome by showing that the electrocardiogram and mutations are the same as in Brugada syndrome. The diagnosis is easily made by means of the ECG when it is typical. There exist, however, patients with concealed and intermittent electrocardiographic forms that make the diagnosis difficult. The ECG can be modulated by changes in autonomic balance, body temperature, glucose level, and the administration of drugs like antiarrhythmics, but also neuroleptic and antimalaria drugs.

Effects of maternal tobacco smoking, sleeping position, and sleep state on arousal in healthy term infants

Abstract: Objectives: To investigate whether a history of maternal tobacco smoking affected the maturation of arousal responses and whether sleeping position and infant age alters these relations. Design: Healthy term infants (13 born to mothers who did not smoke and 11 to mothers who smoked during pregnancy) were studied using daytime polysomnography on three occasions: ( a ) two to three weeks after birth, ( b ) two to three months after birth, and ( c ) five to six months after birth. Multiple measurements of arousal threshold in response to air jet stimulation were made in both active sleep (AS) and quiet sleep (QS) when infants slept both prone and supine. Results: Maternal smoking significantly elevated arousal threshold in QS when infants slept supine at 2–3 months of age (p Conclusions: Maternal tobacco smoking significantly impairs both stimulus induced and spontaneous arousal from QS when infants sleep in the supine position, at the age when the incidence of sudden infant death syndrome is highest.

Physiologic subperiosteal new bone formation: prevalence, distribution, and thickness in neonates and infants.

Abstract: OBJECTIVE. The objective of our study was to determine the prevalence, distribution, and thickness of physiologic subperiosteal new bone formation in neonates and infants.MATERIALS AND METHODS. High-detail postmortem skeletal radiologic surveys of 101 neonates and infants who had died from sudden infant death syndrome were reviewed. The average age at the time of death was 2.6 months (range, 2 weeks—8 months 2 weeks). The location, distribution, and thickness of subperiosteal new bone formation of the long bones were noted and measured with an ocular magnification system.RESULTS. subperiosteal new bone formation was identified in 35 infants (35%), all of whom were between 1 and 4 months of age. The prevalence of subperiosteal new bone formation involving one or more bones was 37% for ages 1-2 months, 55% for ages 2-3 months, and 35% for ages 3-4 months. subperiosteal new bone formation involved the tibia in 29 infants (bilateral involvement in 19) and the femurs in 14 infants (bilateral involvement in 11)...

Hypoplasia of medullary arcuate nucleus in unexpected late fetal death (stillborn infants): a pathologic study.

Abstract: Objectives. To evaluate the frequency, morphology, and pathogenesis (primary or secondary) of the abnormally developed medullary arcuate nucleus (ARCn) in stillbirths. Methods. We examined 26 stillbirths (24 antepartum, 2 intrapartum) that had a gestational age between 25 and 40 weeks and a normal karyotype. All of the stillborns were described as well-developed, with body length and weight proportional to their gestational age. Each case was submitted to complete autopsy examination, which included a systematic gross and microscopic evaluation of the body, the placental disk, and the umbilical cord and membranes. The brainstem was the particular focus of the histologic examination. The study of the various nuclei (nucleus hypoglossus, dorsal vagus motor nucleus, tractus solitarii nucleus, nucleus ambiguus, trigeminal tractus and nucleus, arcuate nucleus, and ventrolateral reticular formation and its neurons and parabrachial/Kolliker-Fuse complex) was performed on transversal serial sections through the entire pons and medulla oblongata. The histologic analysis was supplemented by volumetric reconstruction and immunohistochemical detection of both apoptosis and proliferating cell nuclear antigen. Results. Histologic examination showed abnormalities of the medulla oblongata ARCn in 9 fetuses (35%). In 8, a marked hypoplasia was evident, characterized by a volume reduction of the nucleus accompanied by neuronal depletion, whereas in 1 fetus the nucleus was completely absent (agenesis). The absence of gliosis, the negativity of the proliferating cell nuclear antigen analysis, and the similarities in apoptotic indices between the hypoplastic and well-developed arcuate are in keeping with a primary developmental defect. This anomaly is frequently associated with hypoplasia of the reticular formation and chronic hypoxia. Conclusions. A high frequency of hypoplasia of the ARCn occurs in fetuses who have died “sine causa,” ie, in a similar manner to that observed in sudden infant death syndrome. Chemoreceptors, although not involved in reflexogenic oxygenation in fetal life, become of vital importance intrapartum and postpartum; therefore, whenever impaired in the course of development, chemoreceptors may underlie cardioventilatory abnormalities critical to sudden infant death syndrome.

Prone versus supine sleep position: a review of the physiological studies in SIDS research.

Abstract: A number of physiological studies, published over the last 10 years, have investigated the links between prone sleeping and sudden infant death syndrome (SIDS). This review evaluates those studies and derives an overview of the different affects of sleeping prone or supine in infancy. Generally, compared with the supine, the prone position raises arousal and wakening thresholds, promotes sleep and reduces autonomic activity through decreased parasympathetic activity, decreased sympathetic activity or an imbalance between the two systems. In addition, resting ventilation and ventilatory drive is improved in preterm infants, but in older infants (>1 month), there is no improvement in ventilation, and in 3-month-old infants, the position is adverse in terms of poorer ventilatory drive (in active sleep only). The majority of findings suggest a reduction in physiological control related to respiratory, cardiovascular and autonomic control mechanisms, including arousal during sleep in the prone position. Since the majority of these findings are from studies of healthy infants, continued reinforcement of the supine sleep recommendations for all infants is emphasized.