Hiroshi Nishida

The Effect of Chronic or Intermittent Hypoxia on Cognition in Childhood: A Review of the Evidence

Objective. A review of the evidence concerning the effect of chronic or intermittent hypoxia on cognition in childhood was performed by using both a systematic review of the literature and critical appraisal criteria of causality. Because of the significant impact of behavioral disorders such as attention-deficit/hyperactivity disorder on certain cognitive functions as well as academic achievement, the review also included articles that addressed behavioral outcomes. Methods. Both direct and indirect evidence were collected. A structured Medline search was conducted from the years 1966-2000 by using the OVID interface. Both English- and non–English-language citations were included. Significant articles identified by the reviewers up to 2003 were also included. To be included as direct evidence, an article needed to be an original report in a peer-reviewed journal with data on cognitive, behavioral, or academic outcomes in children up to 14 years old, with clinical conditions likely to be associated with exposure to chronic or intermittent hypoxia. Indirect evidence from other reviews and publications in closely related fields, including experimental studies in adults, was used to help formulate conclusions. Two reviewers screened abstracts and titles. Each article included as direct evidence received a structured evaluation by 2 reviewers. Adjudication of differences was performed by a group of 2 reviewers and a research consultant. After this review, tables of evidence were constructed that were used as the basis for group discussion and consensus development. Indirect evidence assigned by topic to specific reviewers was also presented as part of this process. A formal procedure was used to rank the studies by design strength. The critical appraisal criteria for causation described in Evidence Based Pediatrics and Child Health (Moyer V, Elliott E, Davis R, et al, eds. London, United Kingdom: BMJ Books; 2000:46–55) were used to develop consensus on causality. Results. A total of 788 literature citations were screened. For the final analysis, 55 articles met the criteria for inclusion in the direct evidence. Of these, 43 (78.2%) reported an adverse effect. Of the 37 controlled studies, 31 (83.8%) reported an adverse effect. Adverse effects were noted at every level of arterial oxygen saturation and for exposure at every age level except for premature newborns. The studies were classified into 5 clinical categories: congenital heart disease (CHD), sleep-disordered breathing (SDB), asthma, chronic ventilatory impairment, and respiratory instability in infants. Two of these categories, CHD and SDB, which accounted for 42 (76.4%) of the included articles, fulfilled the Evidence Based Pediatrics and Child Health criteria for causation. The indirect evidence included 8 reviews, 1 meta-analysis, and 10 original reports covering the fields of adult anoxia, animal research, SDB in adults, natural and experimental high-altitude studies, perinatal hypoxic-ischemic encephalopathy, anemia, and carbon-monoxide poisoning. The studies of high-altitude and carbon-monoxide poisoning provided evidence for causality. Conclusions. Adverse impacts of chronic or intermittent hypoxia on development, behavior, and academic achievement have been reported in many well-designed and controlled studies in children with CHD and SDB as well as in a variety of experimental studies in adults. This should be taken into account in any situation that may expose children to hypoxia. Because adverse effects have been noted at even mild levels of oxygen desaturation, future research should include precisely defined data on exposure to all levels of desaturation.

Morbidity and Mortality of Infants With Very Low Birth Weight in Japan: Center Variation

OBJECTIVES. The objectives of this study were to describe the characteristics and morbidity of very low birth weight infants, to identify the medical intervention for these infants, and to evaluate the factors affecting the mortality of these infants among the participating hospitals. METHODS. A large multicenter neonatal research network that included level III NICUs from throughout Japan was established. A standardized mortality rate was formulated by giving a ratio of the observed deaths and the predicted deaths based on a 100-g birth weight interval mortality. A regression model was used to predict the factors that affect neonatal mortality. RESULTS. The network included 37 centers and 2145 infants weighing ≤1500 g, born or admitted to the centers in 2003. Gestational age and birth weight of studied infants were 28.6 ± 3.6 gestational weeks (mean ± SD) and 1025 ± 302 g, respectively. Overall, 11% of the infants died before being discharged from hospitals (range: 0%–21%). The standardized mortality rate varied among the facilities (range: 0%–30%). No association between the annual number of patients admitted and standardized mortality rate was found. Among all of the very low birth weight infants, 14% were outborn infants, 72% were delivered by cesarean sections, 27% had patent ductus arteriosus, 3% had gastrointestinal perforation, 8% had bacterial sepsis, and 13% had intraventricular hemorrhage. Medical interventions involved were: 41% antenatal corticosteroids, 54% surfactant therapy, 18% postnatal steroids for chronic lung disease, and 29% high-frequency oscillatory ventilation. We found variations in the medical interventions and the clinical outcomes among the centers. CONCLUSIONS. The overall survival rate for very low birth weight infants among neonatal centers in Japan was ∼90%. However, differences in the morbidity and mortality were observed among these centers.

International Comparison of Care for Very Low Birth Weight Infants: Parents' Perceptions of Counseling and Decision-Making

Objective. To characterize parent perceptions and satisfaction with physician counseling and delivery-room resuscitation of very low birth weight infants in countries with neonatal intensive care capacity. Study Design. Convenience sample of 327 parents of 379 inborn very low birth weight infants (<1501 g) who had received resuscitation and neonatal intensive care in 9 neonatal intensive care units (NICUs) in 6 Pacific Rim countries and in 2 California hospitals. The sample comprised mostly parents whose infants survived, because in some centers interviews of parents of nonsurviving infants were culturally inappropriate. Of 359 survivors for whom outcome data were asked of parents, 29% were reported to have long-term sequelae. Half-hour structured interviews were performed, using trained interpreters as necessary, at an interval of 13.7 months after the infants birth. We compared responses to interview questions that detailed counseling patterns, factors taken into consideration in decisions, and acceptance of parental decision-making. Results. Parents recall of perinatal counseling differed among centers. The majority of parents assessed physician counseling on morbidity and mortality as adequate in most, but not all, centers. They less commonly perceived discussions of other issues as adequate to their needs. The majority (>65%) of parents in all centers felt that they understood their infants prognosis after physician counseling. The proportion of parents who expected long-term sequelae in their infant varied from 15% (in Kuala Lumpur, Malaysia) to 64% (in Singapore). The majority (>70%) of parents in all centers, however, perceived their infants outcome to be better than they expected from physician counseling. A majority of parents across all centers feared that their infant would die in the NICU, and approximately one third continued to fear that their infant might die at home after nursery discharge. The parents regard for physicians and, to a lesser extent, partners opinions was important in decision-making. Less than one quarter of parents perceived that physicians had made actual life-support decisions on their own except in Melbourne, Australia, and Tokyo, Japan (where 74% and 45% of parents, respectively, reported sole physician decision-making). Parents would have preferred to play a more active, but not autonomous, role in decisions made for their infants. Counseling may heighten parents anxiety during and after their infants hospitalization, but that does not diminish their recalled satisfaction with counseling and the decision-making process. Conclusions. Counseling differs by center among these centers in Australasia and California. Given that parents desire to play an active role in decision-making for their premature infant, physicians should strive to provide parents the medical information critical for informed decision-making. Given that parents do not seek sole decision-making capacity, physicians should foster parental involvement in life-support decisions to the extent appropriate for local cultural norms.

Physician counselling practices and decision-making for extremely preterm infants in the Pacific Rim

Objectives:u2002 This study was undertaken to evaluate physician counselling practices and resuscitation decisions for extremely preterm infants in countries of the Pacific Rim. We sought to determine the degree to which physician beliefs, parents opinion and medical resources influence decision‐making for infants at the margin of viability.

Variation in mortality and intraventricular haemorrhage in occupants of Pacific Rim nurseries

Objective: u2003A network of neonatal intensive care units in Pacific Rim countries was formed to compare infant risk factors, clinical practices, and outcomes for very low birthweight infants.

Neonatal Intensive Care Nurseries in Pacific Rim Countries: Differences in Clinical Practices and Neonatal Mortality. |[dagger]| 1210

A multicenter study comparing outcomes for very low birth weight infants(<1501g) in Pacific Rim nurseries was undertaken. Centers collected prospective data for all liveborn infants beginning January 1996. Data were collected for gestational age (GA), birth weight (BW), 5 minute Apgars, use of antenatal steroids (AS), cesarean rates (CS, surfactant use (Surf), and death. CRIB scores were derived from these data. Centers had similar mean BW (p=0.4). SFGH had less mature infants (p=0.03) and a lower distribution of Apgar scores, as well as the highest mortality. There was significant differences in clinical practices in the use of AS and Surf. Table

A NETWORK OF NEONATAL INTENSIVE CARE UNITS IN PACIFIC RIM COUNTRIES: DIFFERENCES IN ASSOCIATED RISK FACTORS FOR VLBW INFANTS. † 1209

A NETWORK OF NEONATAL INTENSIVE CARE UNITS IN PACIFIC RIM COUNTRIES: DIFFERENCES IN ASSOCIATED RISK FACTORS FOR VLBW INFANTS. † 1209