Sudden infant death syndrome prevention and an understanding of selected clinical issues

DESIGN AND CLINIC MONITORING OF A NEWLY DEVELOPED NON-ATTACHED INFANT APNEA MONITOR

Tragically more babies fall victim to sudden infant death syndrome than the combined numbers of respiratory ailment, heart disease and cancer deaths. The cases take place for those babies who were under one year of age and especially often for those babies who were in the age around two to four month old. Despite extensive research, the exact cause of sudden infant death syndrome is still not known. Shockingly, it can even happen to apparently healthy babies left alone for just a little while. The conventional infant apnea monitor adopts disposable electrodes as sensors for apnea detection and thus inducing the problems of skin irritated or other hazards. To tackle these shortcomings, we develop a non-attached type apnea monitor. The device monitors the temperature of the breathing airflow by means of thermo sensors. These airflow frequencies linking with respiratory rates are indicated on the monitor. There is absolutely no contact with the babies' skin, avoiding the possibilities of any skin irritations. The system detects temperature changes induced by breathing and analyzes the breathing frequency changes displayed with both LED array and computer monitor. The data are collected and analyzed simultaneously by a personal computer, which can link to the central nursery room. The device provides a convenient way for pediatricians or nurses to detect abnormal respiratory frequency in real time so they can handle any emergency and gives the necessary treatment immediately. Ten clinic cases have been analyzed and presented. Function validation of the device, on the other hand, is performed as well.

A Newly Developed Infant Remote Monitoring System

The present invention relates to an infant remote monitoring system, in particular, to one that monitors the heat from the breath of a baby to aid in the prevention of sudden infant death syndrome caused by asphyxia. This innovative device monitors the airflow frequency and temperature of the infant’s breathing using thermosensors. These airflow frequencies, linked with respiratory rates, are indicated on the monitor. The key advantage of this innovation is that it requires absolutely no contact with the baby’s skin, thereby preventing skin irritations and reducing infant discomfort normally found with traditional monitors. The system detects temperature changes induced by breathing and analyzes the breathing frequency changes, displaying the data on both a computer monitor and a light emitting diode array. Data are collected and analyzed simultaneously via personal computer, which can be linked to the central nursery room’s monitoring system. This device provides a convenient way for pediatricians or nurses to detect abnormalities in respiratory frequency in real time, so they can identify and respond to any emergency as it happens and give appropriate treatment immediately. Ten clinical cases were analyzed, and function validation of the device was performed as well.

Idiopathic apparent life-threatening event in Northern Israel

OBJECTIVE

To note whether the incidence of idiopathic apparent life-threatening event (IALTE) has decreased since 1993 in parallel to the decline in the incidence of sudden unexpected death in infancy (SUDI) 2. To compare their epidemiological profile to infants with acute unrelated illness.

METHODS

The discharge diagnoses of each infant investigated for apparent life-threatening event or apnea in the five major hospitals in Northern Israel were reviewed over the period 1991-2000. Infants with identified aetiology or apnea only were excluded. Each infant was matched with two other infants admitted for an acute respiratory illness unrelated to apnea. IALTE rates were compared to the national rates of SUDI.

RESULTS

Two hundred and forty-three infants were diagnosed with IALTE. No evidence for a decline in incidence was noted over the period of the study, while a consistent decline in the incidence of SUDI was observed. Only few differences in the epidemiological profile were noted between the study and the comparison group, that is, increased rate of prematurity and first-born infants.

CONCLUSIONS

(i) The two conditions probably do not share a common aetiology in the majority of cases; and (ii) the epidemiological profile of IALTE is predominantly similar to that of infants hospitalized for respiratory illness.

Promoting parental compliance with home infant apnea monitor use

OBJECTIVE

To promote greater compliance in using prescribed infant apnea monitors among families with a medically at-risk infant. Eight consecutively referred non-compliant families were treated by a medical social worker who provided educational, behavioral prompting, and case management services. In six families results were evaluated with A-B single case research designs, and in two families A-B-A designs were used. Enhanced compliance followed intervention with all eight families. Clinically satisfactory compliance permitting the pediatrician to safely discontinue monitor use occurred in five of the eight families. Simple behavioral and case management interventions show great promise in promoting caregiver compliance with using home-based infant apnea monitors.

Sleeping environments as risk factors of sudden infant death syndrome in Japan

For the purpose of assessing the risk factors of the sleeping environment in SIDS, we performed a population-based, case-control study. Index cases comprised 56 SIDS cases which were diagnosed on the basis of autopsies during a period of 11 years at the Department of Legal Medicine, Faculty of Medicine, University of the Ryukyus. Control cases comprised infants who were examined at regional health centers for Infant Health Screening. The incidence of SIDS obtained was 0.25 per 1000 live births, which was comparable to that obtained in other districts having the established medical examiner's system. The proportion of prone sleeping was 81.0% and 38.3% in the SIDS and control groups, respectively, and an odds ratio was calculated as 10.4 (99% confidence interval, 3.9 to 37.6). This indicates that prone sleeping is a risk factor of SIDS, in Japan, as reported in various countries. Various kinds of bedclothes were used in this country, and our survey of bedclothes in the control revealed their improper use for infants to sleep, particularly with the prone position. In addition, the co-sleeping habit, which was not uncommon in Japan, seems to contribute to certain deaths of infants whose causes of death were controversial. In the investigation of SIDS, therefore, the sleeping environments, such as bedclothes and the co-sleeping habit, as well as the sleeping position should be taken into consideration as risk factors.

Antireflux surgery in children under 3 months of age

PURPOSE

The aim of this study was to analyze the indications and results of fundoplication in 110 infants under 3 months of age.

METHODS

A retrospective review was conducted on the charts of all infants operated on for gastroesophageal reflux disease (GERD) at the UCLA Medical Center from January 1980 to December 1997. There were 59 boys and 51 girls. Recurrent emesis was the indication for operation in 62 of 110 infants, and respiratory symptoms in 85 of 110, with 54 of 110 having both. Neurological impairment was present in 32%. Prematurity was present in 21%; 35% had associated anomalies. Overall, 81 of 110 infants (73.6%) had one or more associated major malformations or disorders. Reflux was confirmed by upper gastrointestinal series findings in 63 of 78, esophageal pH monitoring in 60 of 62, and endoscopy in five of seven.

RESULTS

Mean age at operation was 1.8+/-0.1 months and mean weight was 3,686+/-90.2 g. A Nissen fundoplication was performed on 104 children, and six underwent a Thal procedure. Thirty-one had a gastric emptying procedure for delayed gastric emptying. Complications occurred in 7 infants. Emesis was controlled in 57 of 62 patients, aspiration in 38 of 48, and apneic spells in 54 of 57. Follow-up greater than 6 months was available for 73 patients. There were nine late deaths, all related to severe associated malformations. Seven patients required a redo fundoplication for recurrent reflux.

CONCLUSIONS

Nissen fundoplication can be performed safely in symptomatic infants under 3 months of age with low mortality and morbidity rates and with resolution of the presenting symptoms in 79% of infants.

Effect of sleep state on the laryngeal chemoreflex in neonatal piglets

The laryngeal chemoreflex (LCR) is a brain stem-mediated response that is a potential mechanism for sudden infant death syndrome. The vast majority of sudden infant death occurs during sleep, yet it remains to be established whether there is a particular sleep state that makes an infant animal more susceptible to apneic events via the LCR. The purpose of this study was to investigate the LCR during different sleep states in the neonatal piglet. In this study, continuous physiologic monitoring and electroencephalographic, electro-oculographic, and electromyographic techniques were utilized to study neonatal piglets during a hypnotic induced sleep model. Propofol drip anesthetic was utilized to provide an anesthetic state and was titrated for dose-dependent sedation. The LCR was initiated in 11 animals during quiet sleep, rapid eye movement sleep, and the anesthetic state. Baseline respiratory and cardiovascular responses were measured. Durations of apnea were recorded and compared. This study found that despite known physiologic differences in respiratory control during different sleep states as compared to the anesthetic state, there appears to be no increased risk of profound apnea in one state versus another in piglets 19 to 28 days old.

Influence of sleep states on laryngeal and abdominal muscle response to upper airway occlusion in lambs

This study was aimed at describing abdominal and laryngeal muscle responses to upper airway occlusion (UAO) in early life and the effect of sleep states on these responses. Twelve nonsedated, 9-26-d-old lambs were studied. We simultaneously recorded 1) airflow (pneumotachograph + face mask); 2) sleep states (electrocorticogram and electrooculogram); 3) abdominal muscle (external obliquus) electromyogram (EMG); and 4) glottic constrictor (thyroarytenoid) and dilator (posterior cricoarytenoid and cricothyroid) muscle EMGs. The pneumotachograph was repeatedly occluded for 15-30 s in wakefulness and natural sleep. We analyzed 90 occlusions during wakefulness (11 lambs), 28 during non-rapid eye movement (nREM) sleep (six lambs), and 23 during rapid eye movement (REM) sleep (five lambs). A phasic expiratory external obliquus EMG was present during baseline and progressively increased throughout UAO in wakefulness and nREM sleep, but not in REM sleep. Phasic thyroarytenoid EMG progressively increased during inspiratory efforts throughout UAO in wakefulness and nREM sleep, paralleling the increase in glottic dilator (posterior cricoarytenoid and cricothyroid) EMG. In contrast, glottic muscle response to UAO in REM sleep was severely blunted or disorganized by frequent swallowing movements. We conclude that UAO triggers complex and coordinated laryngeal and abdominal muscle responses during wakefulness and nREM sleep in lambs; these responses are largely absent, however, in REM sleep. These unique results, together with the defective arousal response in REM sleep, suggest that vulnerability to airway occlusion could be increased during REM sleep in early life. Possible implications for understanding severe postnatal apneas are discussed.

Is sudden infant death syndrome a problem in Zimbabwe?

In order to determine the incidence of sudden infant death syndrome (SIDS) in Zimbabwe, a prospective study was done in infants aged 1 month to 1 year who were certified as dead at home and brought to the accident and emergency department of Mpilo Central Hospital in Bulawayo from July 1992 to June 1993. There were four cases of SIDS among a total of 18,889 registered live births, giving an incidence rate for SIDS of approximately 0.2/1000 (95% CI 0.004-0.4/1000). SIDS appears to be uncommon in black Africans of low socio-economic status in Zimbabwe. Child rearing practices, parental lifestyle and a home environment different from that of Europeans might explain the low incidence of SIDS in the population.