Early Magnetic Resonance Imaging Predicts 30-Month Outcomes after Therapeutic Hypothermia for Neonatal Encephalopathy

OBJECTIVE

To evaluate the association of therapeutic hypothermia with magnetic resonance imaging (MRI) findings and 30-month neurodevelopment in term neonatal encephalopathy.

STUDY DESIGN

Cross-sectional analysis of 30-month neurodevelopment (IQR 19.0-31.4) in a prospective cohort of mild-to-severe neonatal encephalopathy imaged on day 4 (1993-2017 with institutional implementation of therapeutic hypothermia in 2007). MRI injury was classified as normal, watershed, or basal ganglia/thalamus. Abnormal motor outcome was defined as Bayley-II psychomotor developmental index <70, Bayley-III motor score <85 or functional motor deficit. Abnormal cognitive outcome was defined as Bayley-II mental developmental index <70 or Bayley-III cognitive score <85. Abnormal composite outcome was defined as abnormal motor and/or cognitive outcome, or death. The association of therapeutic hypothermia with MRI and outcomes was evaluated with multivariable logistic regression adjusted for propensity to receive therapeutic hypothermia.

RESULTS

Follow-up was available in 317 (78%) surviving children, of whom 155 (49%) received therapeutic hypothermia. Adjusting for propensity, therapeutic hypothermia was independently associated with decreased odds of abnormal motor (OR 0.15, 95% CI 0.06-0.40, P < .001) and cognitive (OR 0.11, 95% CI 0.04-0.33, P < .001) outcomes. This association remained statistically significant after adjustment for injury pattern. The predictive accuracy of MRI pattern for abnormal composite outcome was unchanged between therapeutic hypothermia-treated (area under the receiver operating curve 0.76; 95% CI 0.61-0.91) and untreated (area under the receiver operating curve 0.74; 95% CI 0.67-0.81) infants. The negative predictive value of normal MRI was high in therapeutic hypothermia-treated and untreated infants (motor 96% vs 90%; cognitive 99% vs 95%).

CONCLUSIONS

Therapeutic hypothermia is associated with lower rates of brain injury and adverse 30-month outcomes after neonatal encephalopathy. The predictive accuracy of MRI in the first week of life is unchanged by therapeutic hypothermia. Normal MRI remains reassuring for normal 30-month outcome after therapeutic hypothermia.

Newborn metabolic vulnerability profile identifies preterm infants at risk for mortality and morbidity

BACKGROUND

Identifying preterm infants at risk for mortality or major morbidity traditionally relies on gestational age, birth weight, and other clinical characteristics that offer underwhelming utility. We sought to determine whether a newborn metabolic vulnerability profile at birth can be used to evaluate risk for neonatal mortality and major morbidity in preterm infants.

METHODS

This was a population-based retrospective cohort study of preterm infants born between 2005 and 2011 in California. We created a newborn metabolic vulnerability profile wherein maternal/infant characteristics along with routine newborn screening metabolites were evaluated for their association with neonatal mortality or major morbidity.

RESULTS

Nine thousand six hundred and thirty-nine (9.2%) preterm infants experienced mortality or at least one complication. Six characteristics and 19 metabolites were included in the final metabolic vulnerability model. The model demonstrated exceptional performance for the composite outcome of mortality or any major morbidity (AUC 0.923 (95% CI: 0.917-0.929). Performance was maintained across mortality and morbidity subgroups (AUCs 0.893-0.979).

CONCLUSIONS

Metabolites measured as part of routine newborn screening can be used to create a metabolic vulnerability profile. These findings lay the foundation for targeted clinical monitoring and further investigation of biological pathways that may increase the risk of neonatal death or major complications in infants born preterm.

IMPACT

We built a newborn metabolic vulnerability profile that could identify preterm infants at risk for major morbidity and mortality. Identifying high-risk infants by this method is novel to the field and outperforms models currently in use that rely primarily on infant characteristics. Utilizing the newborn metabolic vulnerability profile for precision clinical monitoring and targeted investigation of etiologic pathways could lead to reductions in the incidence and severity of major morbidities associated with preterm birth.

Fish associated with a subsea pipeline and adjacent seafloor of the North West Shelf of Western Australia

Information on the potential ecological value of offshore oil and gas infrastructure is required as it reaches the end of its operational life and decisions must be made regarding the best practice option for decommissioning. This study uses baited remote underwater stereo-video systems to assess fish assemblages along an offshore subsea pipeline and in adjacent natural seabed habitats at ∼140 m depth on the North West Shelf of Western Australia. A total of 955 fish from 40 species and 25 families were recorded. Species richness was, on average 25% higher on the pipeline (6.48 ± 0.37 SE) than off (4.81 ± 0.28 SE) while relative abundance of fish was nearly double on the pipeline (20.38 ± 2.81 SE) than in adjacent natural habitats (10.97 ± 1.02 SE). The pipeline was characterised by large, commercially important species known to associate with complex epibenthic habitat and, as such, possessed a biomass of commercial fish ca 7.5 × higher and catch value ca. 8.6 × ($65.11 ± $11.14 SE) than in adjacent natural habitats ($7.57 ± $2.41 SE). This study has added to the knowledge of fish assemblage associations with subsea infrastructure and provides a greater understanding of the ecological and fisheries implications of decommissioning, helping to better inform decision-making on the fate of infrastructure.

Fish associated with a subsea pipeline and adjacent seafloor of the North West Shelf of Western Australia

Information on the potential ecological value of offshore oil and gas infrastructure is required as it reaches the end of its operational life and decisions must be made regarding the best practice option for decommissioning. This study uses baited remote underwater stereo-video systems to assess fish assemblages along an offshore subsea pipeline and in adjacent natural seabed habitats at ∼140 m depth on the North West Shelf of Western Australia. A total of 955 fish from 40 species and 25 families were recorded. Species richness was, on average 25% higher on the pipeline (6.48 ± 0.37 SE) than off (4.81 ± 0.28 SE) while relative abundance of fish was nearly double on the pipeline (20.38 ± 2.81 SE) than in adjacent natural habitats (10.97 ± 1.02 SE). The pipeline was characterised by large, commercially important species known to associate with complex epibenthic habitat and, as such, possessed a biomass of commercial fish ca 7.5 × higher and catch value ca. 8.6 × ($65.11 ± $11.14 SE) than in adjacent natural habitats ($7.57 ± $2.41 SE). This study has added to the knowledge of fish assemblage associations with subsea infrastructure and provides a greater understanding of the ecological and fisheries implications of decommissioning, helping to better inform decision-making on the fate of infrastructure.

Initial Metabolic Profiles Are Associated with 7-Day Survival among Infants Born at 22-25 Weeks of Gestation

OBJECTIVE

To evaluate the association between early metabolic profiles combined with infant characteristics and survival past 7 days of age in infants born at 22-25 weeks of gestation.

STUDY DESIGN

This nested case-control consisted of 465 singleton live births in California from 2005 to 2011 at 22-25 weeks of gestation. All infants had newborn metabolic screening data available. Data included linked birth certificate and mother and infant hospital discharge records. Mortality was derived from linked death certificates and death discharge information. Each death within 7 days was matched to 4 surviving controls by gestational age and birth weight z score category, leaving 93 cases and 372 controls. The association between explanatory variables and 7-day survival was modeled via stepwise logistic regression. Infant characteristics, 42 metabolites, and 12 metabolite ratios were considered for model inclusion. Model performance was assessed via area under the curve.

RESULTS

The final model included 1 characteristic and 11 metabolites. The model demonstrated a strong association between metabolic patterns and infant survival (area under the curve [AUC] 0.885, 95% CI 0.851-0.920). Furthermore, a model with just the selected metabolites performed better (AUC 0.879, 95% CI 0.841-0.916) than a model with multiple clinical characteristics (AUC 0.685, 95% CI 0.627-0.742).

CONCLUSIONS

Use of metabolomics significantly strengthens the association with 7-day survival in infants born extremely premature. Physicians may be able to use metabolic profiles at birth to refine mortality risks and inform postnatal counseling for infants born at <26 weeks of gestation.

Racial and Ethnic Disparities in Preterm Infant Mortality and Severe Morbidity: A Population-Based Study

BACKGROUND

Disparities exist in the rates of preterm birth and infant mortality across different racial/ethnic groups. However, only a few studies have examined the impact of race/ethnicity on the outcomes of premature infants.

OBJECTIVE

To report the rates of mortality and severe neonatal morbidity among multiple gestational age (GA) groups stratified by race/ethnicity.

METHODS

A retrospective cohort study utilizing linked birth certificate, hospital discharge, readmission, and death records up to 1 year of life. Live-born infants ≤36 weeks born in the period 2007-2012 were included. Maternal self-identified race/ethnicity, as recorded on the birth certificate, was used. ICD-9 diagnostic and procedure codes captured neonatal morbidities (intraventricular hemorrhage, retinopathy of prematurity, periventricular leukomalacia, bronchopulmonary dysplasia, and necrotizing enterocolitis). Multiple logistic regression was performed to evaluate the impact of race/ethnicity on mortality and morbidity, adjusting for GA, birth weight, sex, and multiple gestation.

RESULTS

Our cohort totaled 245,242 preterm infants; 26% were white, 46% Hispanic, 8% black, and 12% Asian. At 22-25 weeks, black infants were less likely to die than white infants (odds ratio [OR] 0.76; 95% confidence interval [CI] 0.62-0.94). However, black infants born at 32-34 weeks (OR 1.64; 95% CI 1.15-2.32) or 35-36 weeks (OR 1.57; 95% CI 1.00-2.24) were more likely to die. Hispanic infants born at 35-36 weeks were less likely to die than white infants (OR 0.66; 95% CI 0.50-0.87). Racial disparities at different GAs were also detected for severe morbidities.

CONCLUSIONS

The impact of race/ethnicity on mortality and severe morbidity varied across GA categories in preterm infants. Disparities persisted even after adjusting for important potential confounders.

Persistent Pulmonary Hypertension of the Newborn in Late Preterm and Term Infants in California

BACKGROUND AND OBJECTIVES

There are limited epidemiologic data on persistent pulmonary hypertension of the newborn (PPHN). We sought to describe the incidence and 1-year mortality of PPHN by its underlying cause, and to identify risk factors for PPHN in a contemporary population-based dataset.

METHODS

The California Office of Statewide Health Planning and Development maintains a database linking maternal and infant hospital discharges, readmissions, and birth and death certificates from 1 year before to 1 year after birth. We searched the database (2007-2011) for cases of PPHN (identified by International Classification of Diseases, Ninth Revision codes), including infants ≥34 weeks' gestational age without congenital heart disease. Multivariate Poisson regression was used to identify risk factors associated with PPHN; results are presented as risk ratios, 95% confidence intervals.

RESULTS

Incidence of PPHN was 0.18% (3277 cases/1 781 156 live births). Infection was the most common cause (30.0%). One-year mortality was 7.6%; infants with congenital anomalies of the respiratory tract had the highest mortality (32.0%). Risk factors independently associated with PPHN included gestational age <37 weeks, black race, large and small for gestational age, maternal preexisting and gestational diabetes, obesity, and advanced age. Female sex, Hispanic ethnicity, and multiple gestation were protective against PPHN.

CONCLUSIONS

This risk factor profile will aid clinicians identifying infants at increased risk for PPHN, as they are at greater risk for rapid clinical deterioration.

Population-based risks of mortality and preterm morbidity by gestational age and birth weight

OBJECTIVE

The objective of this study is to examine the effect of small or large for gestational age (SGA/LGA) status on mortality and morbidity by gestational age.

STUDY DESIGN

Logistic binomial regression was used to calculate relative risks (RRs) and 95% confidence intervals for infant mortality and preterm morbidities for SGA or LGA compared with appropriately grown (AGA) deliveries stratified by gestational age group.

RESULTS

Compared with AGA infants of similar gestational age, SGA infants were at increased risk for infant mortality. Mortality risk was decreased for LGA infants born between 25 and 27 weeks (RR: 0.6) but increased for LGA infants born between 28 and 31 weeks (RR: 1.9). Risk of preterm morbidity was increased for SGA infants born between 28 and 38 weeks, but decreased for LGA infants born before 37 weeks.

CONCLUSION

This study demonstrates the importance of considering birth weight for gestational age when evaluating morbidity and mortality risks.

Survival and Major Morbidity of Extremely Preterm Infants: A Population-Based Study

OBJECTIVES

To assess the rates of mortality and major morbidity among extremely preterm infants born in California and to examine the rates of neonatal interventions and timing of death at each gestational age.

METHODS

A retrospective cohort study of all California live births from 2007 through 2011 linked to vital statistics and hospital discharge records, whose best-estimated gestational age at birth was 22 through 28 weeks. Major morbidities were based on International Classification of Diseases, Ninth Revision, Clinical Modification codes. Survival beyond the first calendar day of life and procedure codes were used to assess attempted resuscitation after birth.

RESULTS

A total of 6009 infants born at 22 through 28 weeks' gestation were included. Survival to 1 year for all live births ranged from 6% at 22 weeks to 94% at 28 weeks. Seventy-three percent of deaths occurred within the first week of life. Major morbidity was present in 80% of all infants, and multiple major morbidities were present in 66% of 22- and 23-week infants. Rates of resuscitation at 22, 23, and 24 weeks were 21%, 64%, and 93%, respectively. Survival after resuscitation was 31%, 42%, and 64% among 22-, 23-, and 24-week infants, respectively. Improved survival was associated with increased birth weight, female sex, and cesarean delivery (P < .01) for resuscitated 22-, 23-, and 24-week infants.

CONCLUSIONS

In a population-based study of extreme prematurity, infants ≤24 weeks' gestation are at highest risk of death or major morbidity. These data can help inform recommendations and decision-making for extremely preterm births.

Disordered animal multilayer reflectors and the localization of light

Multilayer optical reflectors constructed from 'stacks' of alternating layers of high and low refractive index dielectric materials are present in many animals. For example, stacks of guanine crystals with cytoplasm gaps occur within the skin and scales of fish, and stacks of protein platelets with cytoplasm gaps occur within the iridophores of cephalopods. Common to all these animal multilayer reflectors are different degrees of random variation in the thicknesses of the individual layers in the stack, ranging from highly periodic structures to strongly disordered systems. However, previous discussions of the optical effects of such thickness disorder have been made without quantitative reference to the propagation of light within the reflector. Here, we demonstrate that Anderson localization provides a general theoretical framework to explain the common coherent interference and optical properties of these biological reflectors. Firstly, we illustrate how the localization length enables the spectral properties of the reflections from more weakly disordered 'coloured' and more strongly disordered 'silvery' reflectors to be explained by the same physical process. Secondly, we show how the polarization properties of reflection can be controlled within guanine-cytoplasm reflectors, with an interplay of birefringence and thickness disorder explaining the origin of broadband polarization-insensitive reflectivity.

Visual system evolution and the nature of the ancestral snake

The dominant hypothesis for the evolutionary origin of snakes from 'lizards' (non-snake squamates) is that stem snakes acquired many snake features while passing through a profound burrowing (fossorial) phase. To investigate this, we examined the visual pigments and their encoding opsin genes in a range of squamate reptiles, focusing on fossorial lizards and snakes. We sequenced opsin transcripts isolated from retinal cDNA and used microspectrophotometry to measure directly the spectral absorbance of the photoreceptor visual pigments in a subset of samples. In snakes, but not lizards, dedicated fossoriality (as in Scolecophidia and the alethinophidian Anilius scytale) corresponds with loss of all visual opsins other than RH1 (λmax 490-497 nm); all other snakes (including less dedicated burrowers) also have functional sws1 and lws opsin genes. In contrast, the retinas of all lizards sampled, even highly fossorial amphisbaenians with reduced eyes, express functional lws, sws1, sws2 and rh1 genes, and most also express rh2 (i.e. they express all five of the visual opsin genes present in the ancestral vertebrate). Our evidence of visual pigment complements suggests that the visual system of stem snakes was partly reduced, with two (RH2 and SWS2) of the ancestral vertebrate visual pigments being eliminated, but that this did not extend to the extreme additional loss of SWS1 and LWS that subsequently occurred (probably independently) in highly fossorial extant scolecophidians and A. scytale. We therefore consider it unlikely that the ancestral snake was as fossorial as extant scolecophidians, whether or not the latter are para- or monophyletic.

Diminished white matter injury over time in a cohort of premature newborns

OBJECTIVES

To determine the rate of magnetic resonance imaging (MRI)-detected noncystic white matter injury (WMI) in a prospective cohort of premature newborns, and to evaluate its associations with changes in clinical predictors of WMI over the study period.

STUDY DESIGN

A prospective cohort of premature newborns (<33 weeks gestational age) was studied with MRI within 4 weeks of birth and near term-equivalent age. A pediatric neuroradiologist scored the severity of WMI on T1-weighted MRI according to published criteria. WMI was classified as none/mild or moderate/severe. Subjects with severe cystic WMI, periventricular hemorrhagic infarction, or motion artifact on MRI were excluded. Changes in clinical characteristics and predictors of WMI over the study period (1998-2011) were evaluated. Predictors of moderate/severe WMI, including birth year, were evaluated using multivariate logistic regression.

RESULTS

Among 267 newborns, 45 (17%) had moderate/severe WMI. The rate of moderate/severe WMI decreased over the study period (P = .002, χ(2) test for trends). On multivariate logistic regression, the odds of moderate/severe WMI decreased by 11% for each birth year of the cohort (OR, 0.89; 95% CI, 0.81-0.98; P = .02). Prolonged exposure to indomethacin also was independently associated with reduced odds of moderate/severe WMI.

CONCLUSION

The decreasing burden of MRI-detected moderate/severe noncystic WMI in our cohort of premature newborns is independent over time of changes in the known clinical predictors of WMI. Prolonged exposure to indomethacin is associated with reduced WMI.

Perspectives on anticipated quality-of-life and recommendations for neonatal intensive care: a survey of neonatal providers

OBJECTIVE

Explore associations between neonatal providers' perspectives on survival, quality of life (QOL) and treatment recommendations.

METHODS

Providers attending a workshop on neonatal viability were surveyed about survival, perceived QOL and treatment recommendations for marginally viable infants. We assessed associations between estimated survival and perceived QOL and treatment recommendations.

RESULTS

In the 44 included surveys, estimates of survival and QOL varied widely. Maximum care was recommended 80% of the time when anticipated QOL was high, versus 20% when anticipated QOL was low (p < 0.001). Adjusted for confounders, odds of recommending maximum intervention were 4.4 times higher when anticipated QOL was high (95% CI 1.9 - 10.2, p = 0.001).

CONCLUSIONS

The perspectives of practitioners who provide care to critically ill neonates regarding potential survival and QOL vary dramatically and are associated with the treatments those practitioners recommend. Practitioners should take care to avoid basing treatment recommendations on their own perspectives if they are not well aligned with those of the parents.

Resuscitation of neonates at 23 weeks' gestational age: a cost-effectiveness analysis

OBJECTIVE

Resuscitation of infants at 23 weeks' gestation remains controversial; clinical practices vary. We sought to investigate the cost effectiveness of resuscitation of infants born 23 0/7-23 6/7 weeks' gestation.

DESIGN

Decision-analytic modeling comparing universal and selective resuscitation to non-resuscitation for 5176 live births at 23 weeks in a theoretic U.S. cohort. Estimates of death (77%) and disability (64-86%) were taken from the literature. Maternal and combined maternal-neonatal utilities were applied to discounted life expectancy to generate QALYs. Incremental cost-effectiveness ratios were calculated, discounting costs and QALYs. Main outcomes included number of survivors, their outcome status and incremental cost-effectiveness ratios for the three strategies. A cost-effectiveness threshold of $100 000/QALY was utilized.

RESULTS

Universal resuscitation would save 1059 infants: 138 severely disabled, 413 moderately impaired and 508 without significant sequelae. Selective resuscitation would save 717 infants: 93 severely disabled, 279 moderately impaired and 343 without significant sequelae. For mothers, non-resuscitation is less expensive ($19.9 million) and more effective (127 844 mQALYs) than universal resuscitation ($1.2 billion; 126 574 mQALYs) or selective resuscitation ($845 million; 125 966 mQALYs). For neonates, both universal and selective resuscitation were cost-effective, resulting in 22 256 and 15 134 nQALYS, respectively, versus 247 nQALYs for non-resuscitation. In sensitivity analyses, universal resuscitation was cost-effective from a maternal perspective only at utilities for neonatal death <0.42. When analyzed from a maternal-neonatal perspective, universal resuscitation was cost-effective when the probability of neonatal death was <0.95.

CONCLUSIONS

Over wide ranges of probabilities for survival and disability, universal and selective resuscitation strategies were not cost-effective from a maternal perspective. Both strategies were cost-effective from a maternal-neonatal perspective. This study offers a metric for counseling and decision-making for extreme prematurity. Our results could support a more permissive response to parental requests for aggressive intervention at 23 weeks' gestation.

Reflecting optics in the diverticular eye of a deep-sea barreleye fish (Rhynchohyalus natalensis)

We describe the bi-directed eyes of a mesopelagic teleost fish, Rhynchohyalus natalensis, that possesses an extensive lateral diverticulum to each tubular eye. Each diverticulum contains a mirror that focuses light from the ventro-lateral visual field. This species can thereby visualize both downwelling sunlight and bioluminescence over a wide field of view. Modelling shows that the mirror is very likely to be capable of producing a bright, well focused image. After Dolichopteryx longipes, this is only the second description of an eye in a vertebrate having both reflective and refractive optics. Although superficially similar, the optics of the diverticular eyes of these two species of fish differ in some important respects. Firstly, the reflective crystals in the D. longipes mirror are derived from a tapetum within the retinal pigment epithelium, whereas in R. natalensis they develop from the choroidal argentea. Secondly, in D. longipes the angle of the reflective crystals varies depending on their position within the mirror, forming a Fresnel-type reflector, but in R. natalensis the crystals are orientated almost parallel to the mirror's surface and image formation is dependent on the gross morphology of the diverticular mirror. Two remarkably different developmental solutions have thus evolved in these two closely related species of opisthoproctid teleosts to extend the restricted visual field of a tubular eye and provide a well-focused image with reflective optics.

Antenatal education for expectant mothers results in sustained improvement in knowledge of newborn care

OBJECTIVE

Basic perinatal education to increase parental knowledge of neonatal illnesses (such as respiratory distress, sepsis, complications of prematurity) could be a feasible way to reduce high neonatal mortality rates in limited-resource nurseries. To assess the efficacy of antenatal education in increasing mothers' knowledge of basic newborn care in a limited-resource nursery, and to determine whether the knowledge is retained postpartum.

STUDY DESIGN

In March to April 2008, we implemented a 10-min educational program on basic neonatal care for women receiving prenatal care in a maternal child hospital in Vientiane, Laos. The educational intervention was a structured, face-to-face interactive module taught by Lao providers using pictographic and written materials about temperature control, umbilical cord care and signs of neonatal illness. We assessed knowledge before and immediately after the module using a standardized interview tool. When possible, we reassessed knowledge postpartum to determine whether they retained information after the training.

RESULT

We recruited 101 women (average age=26.3 years), and the majority (53%) were primigravidas. Participants were well educated by local standards; 57% of women had >8 years and 28% had >12 years of education. Women's knowledge of neonatal care increased by 10% on immediate posttest (P<0.0001), especially regarding knowledge of umbilical cord care and temperature control (normal temperature ranges, thermometer use). Maternal education (P=0.025) and previous births (P=0.037) correlated positively with higher pretest scores. Higher maternal education correlated with higher posttest scores (P=0.01); however, less-educated women increased their scores as much as did women with more education. Nulliparous women also increased their posttest scores to comparable levels in women with previous deliveries. Women retested after delivery retained the educational message, achieving similar posttest and postdelivery scores (P=0.08).

CONCLUSION

Brief antenatal education increases mothers' understanding of basic newborn care. Mothers retain this knowledge into the early postpartum period and during early infancy when it might help reduce morbidity and mortality. The education was efficacious for women with little education. Brief antenatal educational modules seem a feasible, sustainable means of improving mothers' knowledge of newborn care. We speculate that similar programs could improve neonatal morbidity and mortality in developing countries.

Resuscitation of likely nonviable newborns: would neonatology practices in California change if the Born-Alive Infants Protection Act were enforced?

BACKGROUND

The effects of the Born-Alive Infants Protection Act of 2002, which defines the legal status of live-born infants have not been evaluated.

OBJECTIVE

To study neonatologists' perceptions and the potential effects of the Born-Alive Infants Protection Act and subsequent Department of Health and Human Services enforcement guidelines on resuscitation and comfort care for infants born at 20 to 24 weeks' gestation.

METHODS

From August 2005 to November 2005, we mailed surveys to all 354 neonatologists practicing in California. Surveys asked physicians to characterize their knowledge of and attitudes toward this legislation and enforcement guidelines, current resuscitation and comfort-care practices for extreme prematurity, anticipated changes in practice were the enforced, and demographic information. We hypothesized that enforcement would alter thresholds for resuscitation and care.

RESULTS

We obtained 156 completed surveys (response rate: 44%); 140 fulfilled criteria for analysis. More than half of the neonatologists had not heard of this Act or the enforcement guidelines. Screening examinations at birth were infrequent (<20%) at gestational ages of <23 weeks. Although 63% of neonatologists felt that the Act clarified the definition of born-alive infants, nearly all (>90%) criticized the legislation; only 6% felt that it should be enforced. If it were enforced, physicians predicted that they would lower birth weight and gestational age thresholds for resuscitation and comfort care.

CONCLUSIONS

The Born-Alive Infants Protection Act clarified the legal status of "born-alive" infants, but enforcement guidelines fail to clarify what measures are appropriate when survival is unlikely. The Act may constrain resuscitation options offered to parents, because neonatologists anticipate medicolegal threats if they pursue nonintervention. If this legislation were enforced, respondents predicted more aggressive resuscitation potentially increasing risks of disability or delayed death. Until outcomes for infants of <24 weeks' gestation improve, legislation that changes resuscitation practices for extreme prematurity seems an unjustifiable restriction of physician practice and parental rights.

Barriers to palliative care for children: perceptions of pediatric health care providers

OBJECTIVE

The goal was to explore barriers to palliative care experienced by pediatric health care providers caring for seriously ill children.

METHODS

This study explored pediatric provider perceptions of end-of-life care in an academic children's hospital, with the goal of describing perceived barriers to end-of-life care for children and their families. The report focuses on the responses of nurses (n = 117) and physicians (n = 81).

RESULTS

Approximately one half of the respondents reported 4 of 26 barriers listed in the study questionnaire as frequently or almost always occurring, that is, uncertain prognosis (55%), family not ready to acknowledge incurable condition (51%), language barriers (47%), and time constraints (47%). Approximately one third of respondents cited another 8 barriers frequently arising from problems with communication and from insufficient education in pain and palliative care. Fourteen barriers were perceived by >75% of staff members as occasionally or never interfering with pediatric end-of-life care. Comparisons between physicians and nurses and between ICU and non-ICU staff members revealed several significant differences between these groups.

CONCLUSIONS

Perceived barriers to pediatric end-of-life care differed from those impeding adult end-of-life care. The most-commonly perceived factors that interfered with optimal pediatric end-of-life care involved uncertainties in prognosis and discrepancies in treatment goals between staff members and family members, followed by barriers to communication. Improved staff education in communication skills and palliative care for children may help overcome some of these obstacles, but pediatric providers must realize that uncertainty may be unavoidable and inherent in the care of seriously ill children. An uncertain prognosis should be a signal to initiate, rather than to delay, palliative care.

MR imaging, MR spectroscopy, and diffusion tensor imaging of sequential studies in neonates with encephalopathy

BACKGROUND

Although the imaging, spectroscopic, and diffusion characteristics of brains of infants with neonatal encephalopathy have been described, the time course during which these changes evolve is not clear. The results of sequential MR imaging studies--including anatomic MR imaging, proton MR spectroscopy, and diffusion tensor imaging (DTI)--of 10 patients enrolled prospectively in a study of neonatal encephalopathy are reported to help to clarify the time course of changes in different brain regions during the first 2 weeks of life.

METHODS

Ten neonates were prospectively enrolled in a study of the evolution of MR findings in neonatal encephalopathy and were studied 2 (8 patients) or 3 (2 patients) times within the first 2 weeks of life. The MR examination included spin-echo T1 and T2-weighted images, DTI, and long echo time (288 milliseconds) proton MR spectroscopy. Diffusion parameters (diffusivity [D(av)], fractional anisotropy [FA], and individual eigenvalues) were calculated for 10 1-cm2 regions of interest in each hemisphere that were placed based on anatomic landmarks. D(av) and FA were then measured manually in the same areas on a workstation. Metabolite ratios (NAA/Ch, Cr/Ch, Cr/NAA, Lac/Ch, and Lac/NAA) were calculated in 7 regions of interest. Imaging appearance, diffusion parameters, and metabolite ratios were then evaluated longitudinally (comparing with other studies on the same patient at different times) and cross-sectionally (comparing all studies performed on the same postnatal day).

RESULTS

In most of the patients a characteristic evolution of DTI and MR spectroscopy parameters was seen during the first 2 weeks after birth. Although the anatomic images were normal or nearly normal on the first 2 days after birth in most patients, abnormalities were detected on DTI (both visually and by quantitative interrogation of D(av) maps) and proton MR spectroscopy (abnormal metabolite ratios). These parameters tended to worsen until about day 5 and then normalize, though in several patients abnormal metabolite ratios persisted. Of interest, as areas of abnormal diffusivity pseudonormalized within one region of the brain they would develop in other areas. Therefore, the pattern of injury looked very different when imaging was performed at different times during this evolution.

CONCLUSION

Patterns of injury detected by standard anatomic imaging sequences, DTI sequences, and proton MR spectroscopy varied considerably during the first 2 weeks after injury. The appearance of new areas of reduced diffusion simultaneous with the pseudonormalization of areas that had reduced diffusion at earlier times can result in an entirely different pattern of injury on diffusivity maps acquired at different time points. Awareness of these evolving patterns is essential if studies are performed and interpreted during this critical period of time.

The effect of elevated hydrostatic pressure on the spectral absorption of deep-sea fish visual pigments

The effect of hydrostatic pressure (0.1-54 MPa, equivalent to pressures experienced by fish from the ocean's surface to depths of ca. 5,400 m) on visual pigment absorption spectra was investigated for rod visual pigments extracted from the retinae of 12 species of deep-sea fish of diverse phylogeny and habitat. The wavelength of peak absorption (lambda(max)) was shifted to longer wavelengths by an average of 1.35 nm at 40 MPa (a pressure approximately equivalent to average ocean depth) relative to measurements made at one atmosphere (ca. 0.1 MPa), but with little evidence of a change in absorbance at the lambda(max). We conclude that previous lambda(max) measurements of deep-sea fish visual pigments, made at a pressure close to 0.1 MPa, provide a good indication of lambda(max) values at higher pressures when considering the ecology of vision in the deep-sea. Although not affecting the spectral sensitivity of the animal to any important degree, the observed shift in lambda(max) may be of interest in the context of understanding opsin-chromophore interaction and spectral tuning of visual pigments.

Early brain injury in premature newborns detected with magnetic resonance imaging is associated with adverse early neurodevelopmental outcome

OBJECTIVE

To determine the neurodevelopmental outcome of prematurely born newborns with magnetic resonance imaging (MRI) abnormalities.

STUDY DESIGN

A total of 89 prematurely born newborns (median age 28 weeks postgestation) were studied with MRI when stable for transport to MRI (median age, 32 weeks postgestation); 50 newborns were studied again near term age (median age, 37 weeks). Neurodevelopmental outcome was determined at 18 months adjusted age (median) using the Mental Development Index (Bayley Scales Infant Development II) and a standardized neurologic exam.

RESULTS

Of 86 neonatal survivors, outcome was normal in 51 (59%), borderline in 22 (26%), and abnormal in 13 (15%). Moderate/severe MRI abnormalities were common on the first (37%) and second (32%) scans. Abnormal outcome was associated with increasing severity of white matter injury, ventriculomegaly, and intraventricular hemorrhage on MRI, as well as moderate/severe abnormalities on the first (relative risk [RR] = 5.6; P = .002) and second MRI studies (RR = 5.3; P = .03). Neuromotor abnormalities on neurologic examination near term age (RR = 6.5; P = .04) and postnatal infection (RR = 4.0; P = .01) also increased the risk for abnormal neurodevelopmental outcome.

CONCLUSIONS

In premature newborns, brain abnormalities are common on MRI early in life and are associated with adverse neurodevelopmental outcome.

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 infant's 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 infant's 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 infant's 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 infant's 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

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.

METHODS

A survey was administered to neonatologists and paediatricians who attend deliveries of preterm infants in Australia, Hong Kong, Japan, Malaysia, Taiwan and Singapore. Questions were asked regarding physician counselling practices, decision-making for extremely preterm infants and demographic information.

RESULTS

Physicians counsel parents antenatally with increasing frequency as gestational age increases. Most physicians discuss infant mortality and morbidity with parents prior to delivery. Physicians less frequently discuss the option of no resuscitation of an extremely preterm infant, withdrawal of support at a later time, or financial costs to parents. Severe congenital malformations, perception of a poor future quality of life, parental wishes and a high probability of death for the infant are influential in limiting resuscitation in very preterm infants for a majority of physicians. Less influential factors are parent socioeconomic status, language barriers, financial costs for the family, allocation of national resources, moral or religious considerations, or fear of litigation. Physician thresholds for resuscitation of infants ranged between 22 and 25 weeks gestation and between 400 and 700 g birthweight.

CONCLUSIONS

We report physician beliefs and practices regarding resuscitation and the counselling of parents of extremely preterm infants in Pacific Rim countries. While we find variation among countries, physician practices appear to be determined by ethical decision-making and medical factors rather than social or economic factors in each country.

Patterns of brain injury in term neonatal encephalopathy

OBJECTIVES

To determine whether the pattern of brain injury in term neonatal encephalopathy is associated with distinct prenatal and perinatal factors and to determine whether the pattern of injury is associated with 30-month neurodevelopmental outcome.

STUDY DESIGN

A total of 173 term newborns with neonatal encephalopathy from 2 centers underwent magnetic resonance imaging (MRI) at a median of 6 days of age (range, 1-24 days). Patterns of injury on MRI were defined on the basis of the predominant site of injury: watershed predominant, basal ganglia/thalamus predominant, and normal.

RESULTS

The watershed pattern of injury was seen in 78 newborns (45%), the basal ganglia/thalamus pattern was seen in 44 newborns (25%), and normal MRI studies were seen in 51 newborns (30%). Antenatal conditions such as maternal substance use, gestational diabetes, premature rupture of membranes, pre-eclampsia, and intra-uterine growth restriction did not differ across patterns. The basal ganglia/thalamus pattern was associated with more severe neonatal signs, including more intensive resuscitation at birth ( P = .001), more severe encephalopathy ( P = .0001), and more severe seizures ( P = .0001). The basal ganglia/thalamus pattern was associated with the most impaired motor and cognitive outcome at 30 months.

CONCLUSION

The patterns of brain injury in term neonatal encephalopathy are associated with different clinical presentations and neurodevelopmental outcomes. Measured prenatal risk factors did not predict the pattern of brain injury.

Intensive care for very low birthweight infants in South Africa: a survey of physician attitudes, parent counseling and resuscitation practices

Improving outcomes have promoted utilization of intensive care for premature infants in developing countries with available fiscal and technological resources. Physician counseling and decision-making have not been characterized where economic restrictions, governmental guidelines, and physician cultural attitudes may influence decisions about the appropriateness of neonatal intensive care. A cross-sectional survey of all neonatologists and pediatricians providing neonatal care in public and private hospitals in South Africa (n=394) was carried out. Physicians returned 93 surveys (24 per cent response rate). Frequency of counseling increased with increasing gestational age (GA) but was not universally provided at any GA. Morbidity and mortality were consistently discussed and fiscal considerations frequently discussed when antenatal counseling occurred. Resuscitation thresholds were 25-26 weeks and 665-685 g, and were higher in public than in private hospitals. Decisions to limit resuscitation were based more on expected outcome than on patients' wishes or economics. At 24-25 weeks, 91 per cent of physicians would not resuscitate despite parents' wishes; 93 per cent of physicians would resuscitate 28-29-week-old infants over parents' refusal. Parents expecting premature infants are not invariably counseled. In making life-support decisions, physicians consider infants' best interests and, less frequently, financial and emotional burdens. Thresholds for resuscitation and intensive care are higher in public hospitals, and higher than in developed countries. Physicians relegate parents to a passive role in life-support decisions.

Perinatal stroke in term infants with neonatal encephalopathy

In a prospective cohort of 124 encephalopathic term infants, six infants had an acute focal stroke. All six encephalopathic patients with strokes presented with seizures. Neurodevelopmental outcome at 30 months was abnormal in all six patients and significantly worse when compared with the entire cohort overall. These findings suggest that in newborns with encephalopathy, acute focal strokes are an uncommon but serious occurrence with substantial risk for abnormal neurodevelopmental outcome.

Parental perception of neonatal intensive care in public sector hospitals in South Africa

BACKGROUND

Little is known about parental experience and decision making with regard to premature infants requiring intensive care in developing countries. We undertook this study to characterise parents' experience of physician counselling and their role in making life-support decisions for very low-birth-weight (VLBW) (birth weight < 1 501 g) infants born in South Africa's public-sector neonatal intensive care units (NICUs).

METHODS

Parents of surviving VLBW infants treated in three Johannesburg-area public hospitals and attending follow-up clinics in August 2001 were interviewed regarding their experience of perinatal counselling on outcomes (pain, survival, disability), perception of actual and optimal decision making, and satisfaction with NICU communication.

RESULTS

Parents of 51 infants were interviewed. Seventy-five per cent of parents reported antenatal counselling by physicians on at least one perinatal topic (severe disability, pain, death, finances or religious/moral considerations). The majority of parents (> 60%) who received counselling thought that these topics had been discussed adequately. Most parents reported that doctors had the primary decision-making role, either without consulting them (41%) or after consulting them (37%). Joint decision making was rare (14%). Parents wanted more input in life-support decisions than they reported being given.

CONCLUSION

Counselling is not consistently provided in public-sector hospitals in Johannesburg. Parents of premature infants want a larger share in NICU decision making than they currently experience. Most parents were satisfied with communication later during their infant's hospitalisation. South Africa presents a unique opportunity to study the use of advanced medical technologies in a nation with marked disparities in access to care.

Is exposure to cocaine or cigarette smoke during pregnancy associated with infant visual abnormalities?

The aim of this study was to assess the association between cocaine or cigarette smoke exposure in utero and visual outcome. A total of 153 healthy infants (89 males, 64 females; gestational age range 34 to 42 weeks) were prospectively enrolled in a masked, race-matched study. Quantitative analyses of urine and meconium were used to document exposure to cigarette smoke and cocaine. Infants with exposure to other illicit drugs, excepting marijuana, were excluded. At 6 weeks of age, grating acuity and visual system abnormalities (VSA; eyelid oedema, gaze abnormalities, and visual inattention) of 96 infants from the original study sample were assessed with the Teller acuity card procedure and a detailed neurological examination. Neither cocaine nor cigarette smoke exposure was associated with acuity or VSA. However, VSAs were associated with abnormal neurological examination, independent of drug exposure and other risk factors (odds ratio 7.9; 95% confidence interval 2.0 to 31.5;p=0.004). This unexpected finding could prove a helpful clinical marker for the infant at risk for neurological abnormalities.

Clinical signs predict 30-month neurodevelopmental outcome after neonatal encephalopathy

OBJECTIVE

This study was undertaken to determine the value of a neonatal encephalopathy score (ES) and the presence of seizures for predicting 30-month neurodevelopmental outcome.

STUDY DESIGN

In a cohort study, 68 term newborn infants with encephalopathy were evaluated with an ES based on alertness, feeding, tone, respiratory status, reflexes, and seizure activity (range: 0-6). Seizures were noted as present or absent clinically. Significant cognitive deficits (Mental Development Index <70), motor disability (spastic triplegia/quadriplegia), or death were abnormal outcomes.

RESULTS

Twenty-two newborn infants (32%) had abnormal outcomes. With the use of maximum ES and presence of seizures from days 1 to 3 of life, 87% of newborn infants were correctly classified (area under receiver operating curve 0.93). By using ES and presence of seizures on day 1 only, 87% of newborn infants were correctly classified (area under receiver operating curve 0.89).

CONCLUSION

The severity of neonatal encephalopathy and the presence of seizures are valuable predictors of 30-month neurodevelopmental outcome, as early as the first day of life.

Nucleated red blood cell counts: not associated with brain injury or outcome

The objective was to determine whether an elevated nucleated red blood cell count at birth after perinatal depression is associated with brain injury as measured by (1) proton magnetic resonance spectroscopy and (2) abnormal neurodevelopmental outcome at 30 months of age. The nucleated red blood cell counts from the first 24 hours of life were statistically analyzed in 33 term infants enrolled in a prospective study of the value of magnetic resonance imaging for the determination of neurodevelopmental outcome after perinatal depression. Nucleated red blood cell counts were elevated in 13/33 (39%). Abnormal outcome (19/33, 54%) was associated with Score for Neonatal Acute Physiology-Perinatal Extension (P = 0.04), decreased N-acetylaspartate to choline ratio in the basal ganglia (P = 0.009), and increased lactate to choline ratio in the basal ganglia (P = 0.02), but not with cord pH, Apgar score, or nucleated red blood cell value. In a logistic regression model, increasing nucleated red blood cell counts did not increase the odds of an abnormal outcome at 30 months of age (OR 1.02, P = 0.17). In a population of neonates with perinatal depression, the nucleated red blood cell count at birth does not correlate with magnetic resonance spectroscopy or 30-month neurodevelopmental outcome. The nucleated red blood cell count should not be used as a surrogate marker for subsequent brain injury.

Comparing the diagnosis of white matter injury in premature newborns with serial MR imaging and transfontanel ultrasonography findings

BACKGROUND AND PURPOSE

The accurate identification of white matter injury in premature neonates is important for counseling parents and for targeting these high risk neonates for appropriate rehabilitation services. The objective of this study was to compare the diagnosis of white matter injury detected by serial MR imaging and ultrasonography of a contemporary cohort of premature neonates.

METHODS

Each of the 32 consecutively enrolled neonates was studied with MR imaging at a median postconceptional age of 31.9 weeks (range, 27.6-38.1 weeks) and again at a median postconceptional age of 36.5 weeks (range, 33.4-42.9 weeks) and with serial ultrasonography according to a clinical protocol. Because periventricular echogenicity shown on ultrasonograms evolves over time, both the highest grade of echogenicity and the grade of echogenicity shown on the last neonatal ultrasonogram were used in the analysis to determine the predictive values and correlation (Spearman's rho) of ultrasonography for predicting white matter abnormalities shown on MR images.

RESULTS

White matter abnormalities were diagnosed in 18 (56%) neonates based on MR imaging, consisting of foci of scattered T1 hyperintensity in the periventricular white matter, and in 22 (69%) neonates based on ultrasonography, consisting of abnormal periventricular echogenicity. The severity of white matter abnormalities shown by MR imaging was not correlated with the highest grade of white matter abnormalities detected with ultrasonography (rho=0.18, P=.3) or with the grade of white matter abnormalities shown on the last ultrasonogram (rho = 0.16, P=.4).

CONCLUSION

Although ultrasonography is commonly used to screen premature neonates for white matter injury, it was not a sensitive predictor of the milder spectrum of MR imaging-defined white matter abnormalities.

Encephalopathy as a predictor of magnetic resonance imaging abnormalities in asphyxiated newborns

Basal ganglia abnormalities on magnetic resonance imaging predict neurodevelopmental impairment in newborns with perinatal depression. We determined the value of a clinical encephalopathy score as a predictor of abnormal magnetic resonance imaging results in newborns with perinatal depression. We assigned a neonatal encephalopathy score to 101 newborns. The encephalopathy score, based on alertness, feeding, tone, respiratory status, reflexes, and seizure activity, was assigned once daily. The maximum score from the first 3 days of life was compared with abnormal magnetic resonance imaging results present globally or solely in the basal ganglia.Eighty-one percent of patients manifested abnormalities on any magnetic resonance imaging sequence, and 37% manifested abnormalities in the basal ganglia alone. The encephalopathy score correlated well with magnetic resonance imaging abnormalities in the basal ganglia (Spearman Rho = 0.335, P < 0.0001). Newborns with mild and severe encephalopathy had likelihood ratios of 0.41 and 7.4, respectively, for abnormal basal ganglia magnetic resonance imaging results. Newborns with moderate encephalopathy (composing 47% of the cohort) manifested basal ganglia abnormalities with a likelihood ratio of 0.785. Severe clinical encephalopathy correlates with abnormal basal ganglia magnetic resonance imaging results, and mild encephalopathy correlates with a normal magnetic resonance imaging result. However, standard clinical criteria do not alter the prior risk of abnormal basal ganglia magnetic resonance imaging results for newborns with moderate encephalopathy.

Serial quantitative diffusion tensor MRI of the premature brain: development in newborns with and without injury

PURPOSE

To determine the change over time of the apparent diffusion coefficient (ADC) and relative anisotropy of cerebral water in a cohort of premature newborns serially studied near birth and again near term.

MATERIALS AND METHODS

Newborns were classified as normal (N = 11), minimal white matter injury (N = 7), or moderate white matter injury (N = 5).

RESULTS

ADC decreased significantly with age in all brain regions in newborns classified as normal and those with minimal white matter injury. ADC increased with age or failed to decline in widespread areas of white matter in newborns with moderate white matter injury. Anisotropy increased with age in all white matter regions in newborns classified as normal. Anisotropy did not increase in frontal white matter in those with minimal white matter injury, and in widespread white matter areas in those with moderate white matter injury.

CONCLUSION

This study demonstrates that serial diffusion tensor magnetic resonance imaging scans of premature newborns can detect differences in white matter maturation in infants with and without white matter injury.

Predictors of 30-month outcome after perinatal depression: role of proton MRS and socioeconomic factors

The objective was to determine in infants with perinatal depression whether the relative concentrations of N-acetylaspartate and lactate in the neonatal period are associated with (1) neurodevelopmental outcome at 30 mo of age or (2) deterioration in outcome from age 12 to 30 mo; and to determine whether socioeconomic factors are associated with deterioration in outcome. Thirty-seven term neonates were prospectively studied with single-voxel proton magnetic resonance spectroscopy of the basal nuclei and intervascular boundary zones. Thirty-month outcomes were classified as normal [if Mental Development Index of the Bayley Scales of Infant Development (MDI) >85 and neuromotor scores (NMS) <3; n = 15], abnormal [if MDI <or=85 and/or NMS >or=3 at 12 and 30 mo; n = 11], or deteriorated [if normal at 12 mo and abnormal at 30 mo (MDI <or=85 or NMS >or=3); n = 11]. Thirty percent (11/37) of our cohort deteriorated between 12 and 30 mo. N-acetylaspartate/choline decreased across the groups ordered as normal, deteriorated, and abnormal [in basal nuclei (p <or= 0.001) and intervascular boundary zones (p = 0.04)], but was not different between the normal and deteriorated groups (p = 0.08). Lactate/choline similarly increased across the groups [in basal nuclei (p = 0.01) and intervascular boundary zones (p = 0.05)]. The odds of deterioration, if normal at 12 mo, increased by a factor of 5.1 (95% confidence interval: 1.3-19.8) with each decrease in one of four household income strata. Infants with perinatal depression are at high risk of developmental deterioration between 12 and 30 mo of age, particularly if in a lower income home or with intermediate values of cerebral metabolites on neonatal proton magnetic resonance spectroscopy.

Pain during Mogen or PlastiBell circumcision

Routine neonatal circumcision can be a painful procedure. Although analgesia for circumcision has been studied extensively, there are few studies comparing which surgical technique may be associated with the least pain and discomfort when carried out by pediatric trainees.

OBJECTIVE

We studied two commonly used techniques for circumcision to determine which was associated with less pain and discomfort.

STUDY DESIGN

In a randomized, prospective, but not blinded study, newborns were circumcised either by Mogen clamp or by PlastiBell. All received dorsal nerve blocks with lidocaine. Fifty-nine well, term, newborn infants at San Francisco General Hospital were studied from 1997 to 1998. Circumcisions were carried out mostly by interns and residents in family practice and pediatrics. Pain was assessed by measuring duration of the procedure and by a simple behavioral score done sequentially.

RESULTS

Dorsal nerve blocks were judged to be fully effective in over 70% of cases. Neither Mogen nor PlastiBell was associated with greater pain per 3-minute time period, but the PlastiBell technique on average took nearly twice as long as the Mogen procedure (20 vs 12 minutes). We judged that 60% of the infants had pain or discomfort associated with the procedure that was excessive. Residents and interns universally preferred the Mogen technique over the PlastiBell because of the former's simplicity.

CONCLUSION

During the procedure, Mogen circumcision is associated with less pain and discomfort, takes less time, and is preferred by trainees when compared with the PlastiBell.

Seizure-associated brain injury in term newborns with perinatal asphyxia

BACKGROUND

There is controversy over whether seizures, the most common manifestation of neonatal brain injury, may themselves damage the developing brain.

OBJECTIVE

To determine if neonatal seizures are independently associated with brain injury in newborns with perinatal asphyxia.

METHODS

Ninety term neonates were studied with MRI and single-voxel (1)H-MRS on median day of life 6 (range 1 to 13 days). The severity of MR abnormality in the (1)H-MRS regions of interest was scored using a validated scale. Seizure severity was scored based on seizure frequency and duration, EEG findings, and anticonvulsant administration. Multivariable linear regression tested the independent association of seizure severity with impaired cerebral metabolism measured by lactate/choline and compromised neuronal integrity measured by N-acetylaspartate/choline in both regions.

RESULTS

Clinical seizures occurred in 33 of 90 infants (37%). Seizure severity was associated with increased lactate/choline in both the intervascular boundary zone (p < 0.001) and the basal nuclei (p = 0.011) when controlling for potential confounders of MRI abnormalities and amount of resuscitation at birth. Each increase in seizure score was independently associated with a 21% increase in lactate/choline in the intervascular boundary zone (95% CI, 5.1-38.2%) and a 15% increase in the basal nuclei (95% CI, 0.1-31.7%). Seizure severity was independently associated with diminished N-acetylaspartate/choline in the intervascular boundary zone (p = 0.034).

CONCLUSION

The severity of seizures in human newborns with perinatal asphyxia is independently associated with brain injury and is not limited to structural damage detectable by MRI.

Visual pigments and optical habitats of surfperch (Embiotocidae) in the California kelp forest

We studied the optical microhabitat use and visual pigment variation among a group of closely related teleosts (surfperch: Embiotocidae) living along the nearshore central California coast. We employed a diver-operated spectroradiometer to record the optical microhabitat use of eight surfperch species in Monterey Bay. and microspectrophotometry to measure visual pigment absorbance for nine surfperch species. Species were dichromatic with mixtures of A1- and A2-based visual pigments exhibiting extensive maximum absorbance (lambda(max)) variation across species: 455-482 nm for SWS cones and 527-546 nm for LWS cones. Interspecific variation in sidewelling irradiance measurements (mean lambdaFmaxs) significantly accounted for 63% of the variation in surfperch LWS visual pigments and 83% of the interspecific variation in SWS visual pigments using a phylogenetically-corrected regression technique. Optimality models for maximizing relative photon capture of background radiance demonstrate that the LWS cone lambda(max) values are tuned for maximizing photon capture of the species-specific horizontal visual field, while the SWS cone lambda(max), are well offset from the dominant background radiance. This study is one of the first to demonstrate species-specific differences in habitat usage at microhabitat scales accounting for differences in photoreceptor peak absorbance among closely related, sympatric species.

The molecular basis for spectral tuning of rod visual pigments in deep-sea fish

Most species of deep-sea fish possess of a rod-only retina with a pigment that is generally shortwave shifted in λmax towards the blue region of the spectrum. In addition, the λmax values of different species tend to cluster at particular points in the spectrum. In this study, the rod opsin gene sequences from 28 deep-sea fish species drawn from seven different Orders are compared. The λmax values of the rod pigments vary from approximately 520 nm to &lt;470 nm, with the majority lying between 490 nm and 477 nm. The 520 nm pigment in two species of dragon fish is associated with a Phe261Tyr substitution, whereas the shortwave shifts of the pigments in the other 26 species are accountable by substitutions at a further eight sites (83, 122, 124, 132, 208, 292, 299 and 300). Clustering of λmax values does not, however, involve a common subset of these substitutions in the different species. A phylogenetic analysis predicts that the pigment in the ancestral species would have had a λmax of approximately 480 nm. A total of 27 changes is required to generate the pattern of substitutions seen in the different species, with many sites undergoing multiple changes.

Proton spectroscopy and diffusion imaging on the first day of life after perinatal asphyxia: preliminary report

BACKGROUND AND PURPOSE

MR techniques have proved useful in assessing brain injury from perinatal asphyxia when the injury is subacute or chronic. Recent advances in understanding the molecular mechanisms of brain injury have made medical intervention plausible, creating a need for assessment of the brain within the first few hours of life. We report the results of early (first 24 hours after birth) MR imaging in seven patients, including proton MR spectroscopy in six.

METHODS

MR studies were performed within the first 24 hours of life in seven consecutive patients who were encephalopathic after complicated deliveries. Standard T1-, T2-, and diffusion-weighted sequences were performed in all patients; single-voxel MR spectroscopy was performed in two locations in six of the seven patients. Follow-up MR studies were performed in four patients at ages 7, 8, 9, and 15 days, respectively.

RESULTS

T1-weighted images were normal in all seven patients. T2-weighted images were normal in three patients and showed T2 prolongation in the basal ganglia or white matter in the other four. Diffusion images showed small abnormalities in the lateral thalami or internal capsules in all seven patients. Comparison with clinical course in all seven patients and with follow-up MR studies in four showed that the diffusion images underestimated the extent of brain injury. Proton MR spectroscopy showed substantial lactate elevation in all six of the patients studied. Two patients died in the neonatal period and the other five were left with clinically significant neurologic impairment.

CONCLUSION

MR spectroscopy performed in the first 24 hours after birth is sensitive to the presence of hypoxic-ischemic brain injury, whereas diffusion imaging may help identify but underestimate the extent of the injury. Further studies are ongoing in an attempt to expand upon this observation.

Three-dimensional proton MR spectroscopic imaging of premature and term neonates

BACKGROUND AND PURPOSE

Previous studies have primarily used single-voxel techniques to obtain MR spectra from the neonatal brain. In this study, we applied 3D MR spectroscopic imaging techniques to detect the spatial distribution of MR spectroscopic imaging-detectable compounds in premature and term infants. The goals were to test the feasibility of obtaining 3D MR spectroscopic images of newborns, assess the spatial variations of metabolite levels, and determine age-dependent differences in MR spectroscopic imaging data.

METHODS

MR spectroscopic imaging data were acquired from nine premature (postconceptional age, 30-34 weeks) and eight term (postconceptional age, 38-42 weeks) neonates, all with normal clinical and neurologic outcomes. A specialized point-resolved spectroscopy sequence with very selective saturation pulses was used to select a region encompassing the majority of the brain. Phase encoding in three dimensions was performed in a 17-minute acquisition time to obtain 3D spectral arrays with a 1.0 cm(3) nominal spatial resolution.

RESULTS

This study showed the feasibility of detecting the 3D distributions of choline, creatine, and N-acetylaspartate resonances in the neonatal brain. Significant spectral differences were detected among anatomic locations and between the premature and term groups.

CONCLUSION

This initial study indicates that 3D MR spectroscopic imaging of the neonatal brain can detect anatomic and age-dependent variations in metabolite levels. This technique seems to be a powerful tool to assess the metabolic differences between anatomic regions and to follow the changes in cellular metabolites with brain maturation. This study also indicates the need for determining topologic and age-matched normative values before metabolic abnormalities in neonates can be accurately assessed by MR spectroscopy.

Antenatal counselling, resuscitation practices and attitudes among Australian neonatologists towards life support in extreme prematurity

A questionnaire survey of Australian neonatologists was conducted to ascertain their antenatal counselling and resuscitation practices, and attitudes towards life support in the extremely preterm infant. This study showed that in antenatal parental counselling, whether a paediatrician was given the opportunity to participate depends on the gestation at the time of the threatened preterm delivery The counselling employed almost invariably covered mortality and morbidity. The obstetrician's opinion was considered to be of utmost importance. Both financial and moral obligations were found to be of little importance in counselling and resuscitation. Only one-third of institutions had guidelines for limiting resuscitation. The onus remained on the neonatologists concerning which infant to resuscitate, and the level of the resuscitation to be conducted. In Australia, resuscitation at birth was restricted to infants of 23 weeks' gestation or above, and neonatologists did not believe the legal system has a role to play in limiting or mandating resuscitation of extremely preterm infants. Neither were they concerned with the threat of litigation when they decide to limit resuscitation. The majority of neonatologists agreed with their institution's approach to life support in extremely preterm infants. One grey area was the question of withholding assisted feeding in an infant for which the decision to withdraw life support has been made. Australia lacked a current consensus policy on selective non-treatment. The establishment of national guidelines would be helpful to aid Australian obstetricians and neonatologists in their clinical practice.

The management of extremely premature infants and the perceptions of viability and parental counselling practices of Australian obstetricians

The attitudes of Australian obstetricians to the resuscitation of extremely premature infants are reported. A structured questionnaire including questions regarding antenatal parent counselling, resuscitation practices, survival rates and personal attitudes about life support was distributed to obstetricians working in Australian hospitals with a Level 3 nursery Eighty-nine (48% response rate) replies were received from 12 units located in seven major cities. Obstetricians are more likely to discuss resuscitation with prospective parents with increasing gestation with a major shift occurring at 23-24 weeks' gestation. They strive for consensus with parents regarding resuscitation options and they act upon the opinion of both the prospective parents and their paediatric colleagues. Threat of litigation rarely influences the decision to limit resuscitation of an extremely preterm infant. Obstetricians may underestimate the prognosis for extremely preterm infants. The data presented offer useful insights into current attitudes and practice of tertiary hospital obstetricians.

Is the ultraviolet waveband a special communication channel in avian mate choice?

There is growing evidence that ultraviolet (UV) wavelengths play an important role in avian mate choice. One of the first experiments to support this idea showed that female zebra finches (Taeniopygia guttata) prefer UV-reflecting males to males whose ultraviolet reflection has been removed. The effect was very strong despite little or no UV reflection from several plumage areas. However, it is not clear how the importance of the UV waveband compares to other regions of the bird-visible spectrum. We tested whether the response of female zebra finches to the removal of male UV reflection is greater than to the removal of other wavebands. We presented females with a choice of males whose appearance was manipulated using coloured filters. The filters removed single blocks of the avian visible spectrum corresponding closely to the spectral sensitivities of each of the zebra finch’s single cone classes. This resulted in males that effectively had no UV (UV−), no short-wave (SW−), no medium-wave (MW−) or no long-wave (LW−) plumage reflection. Females preferred UV− and SW− males. LW− and MW− males were least preferred, suggesting that female zebra finches show the greatest response to the removal of longer wavelengths. Quantal catches of the single cone types viewing body areas of the male zebra finch are presented for each treatment. Our study suggests it is important to consider the role of the UV waveband in avian mate choice in conjunction with the rest of the avian visible spectrum.

Delivery room resuscitation decisions for extremely low birthweight infants in California

OBJECTIVE

To characterize physician-parent counseling and delivery room resuscitation of extremely low birthweight (ELBW) infants.

STUDY DESIGN

Cross-sectional survey of 473 California neonatologists detailing counseling patterns, resuscitation thresholds, and acceptance of parental decision making.

RESULTS

The response rate was 61%. After 23 weeks' gestation, > 80% of neonatologists counseled parents expecting ELBW infants. All (> 99%) counseled parents about mortality; > 25% reported not discussing limiting resuscitation or death despite resuscitation. Decisions to limit resuscitation were affected by congenital anomalies, parents' wishes, or perceptions of pain, suffering, and quality of life. Nearly 70% of neonatologists supported parental decision making at 22 to 23 weeks, whereas 66% to 74% responded that parents should not be allowed to make nonresuscitation decisions after 26 weeks. Median resuscitation thresholds were 23 weeks (range 20-28) and 500 g (range 350-1000).

CONCLUSIONS

Neonatologists' failure to discuss nonresuscitation options, variations in resuscitation thresholds, and unwillingness to accept nonresuscitation decisions for more mature ELBW infants may restrict parental decision making.

Seven retinal specializations in the tubular eye of the deep-sea pearleye, Scopelarchus michaelsarsi: a case study in visual optimization

The deep-sea pearleye, Scopelarchus michaelsarsi (Scopelarchidae) is a mesopelagic teleost with asymmetric or tubular eyes. The main retina subtends a large dorsal binocular field, while the accessory retina subtends a restricted monocular field of lateral visual space. Ocular specializations to increase the lateral visual field include an oblique pupil and a corneal lens pad. A detailed morphological and topographic study of the photoreceptors and retinal ganglion cells reveals seven specializations: a centronasal region of the main retina with ungrouped rod-like photoreceptors overlying a retinal tapetum; a region of high ganglion cell density (area centralis of 56.1 x 10(3) cells per mm2) in the centrolateral region of the main retina; a centrotemporal region of the main retina with grouped rod-like photoreceptors; a region (area giganto cellularis) of large (32.2+/-5.6 microm2), alpha-like ganglion cells arranged in a regular array (nearest neighbour distance 53.5+/-9.3 microm with a conformity ratio of 5.8) in the temporal main retina; an accessory retina with grouped rod-like photoreceptors; a nasotemporal band of a mixture of rod- and cone-like photoreceptors restricted to the ventral accessory retina; and a retinal diverticulum comprised of a ventral region of differentiated accessory retina located medial to the optic nerve head. Retrograde labelling from the optic nerve with DiI shows that approximately 14% of the cells in the ganglion cell layer of the main retina are displaced amacrine cells at 1.5 mm eccentricity. Cryosectioning of the tubular eye confirms Matthiessen's ratio (2.59), and calculations of the spatial resolving power suggests that the function of the area centralis (7.4 cycles per degree/8.1 minutes of arc) and the cohort of temporal alpha-like ganglion cells (0.85 cycles per degree/70.6 minutes of arc) in the main retina may be different. Low summation ratios in these various retinal zones suggests that each zone may mediate distinct visual tasks in a certain region of the visual field by optimizing sensitivity and/or resolving power.

Colour vision in billfish

Members of the billfish family are highly visual predatory teleosts inhabiting the open ocean. Little is known about their visual abilities in detail, but past studies have indicated that these fishes were likely to be monochromats. This study, however, presents evidence of two anatomically distinct cone types in billfish. The cells are arranged in a regular mosaic pattern of single and twin cones as in many fishes, and this arrangement suggests that the different cone types also show different spectral sensitivity, which is the basis for colour vision. First measurements using microspectrophotometry (MSP) revealed a peak absorption of the rod pigment at 484 nm, indicating that MSP, despite technical difficulties, will be a decisive tool in proving colour vision in these offshore fishes. When hunting, billfish such as the sailfish flash bright blue bars on their sides. This colour reflects largely in ultraviolet (UV) light at 350 nm as revealed by spectrophotometric measurements. Billfish lenses block light of wavelengths below 400 nm, presumably rendering the animal blind to the UV component of its own body colour. Interestingly, at least two prey species of billfish have lenses transmitting light in the UV waveband and are therefore likely to perceive a large fraction of the UV peak found in the blue bar of the sailfish. The possible biological significance of this finding is discussed.

Long-wave sensitivity in deep-sea stomiid dragonfish with far-red bioluminescence: evidence for a dietary origin of the chlorophyll-derived retinal photosensitizer of Malacosteus niger

Both residual downwelling sunlight and bioluminescence, which are the two main sources of illumination available in the deep sea, have limited wavebands concentrated around 450-500 nm. Consequently, the wavelengths of maximum absorption (lambdamax) of the vast majority of deep-sea fish visual pigments also cluster in this part of the spectrum. Three genera of deep-sea loose-jawed dragonfish (Aristostomias, Pachystomias and Malacosteus), however, in addition to the blue bioluminescence typical of most deep-sea animals, also produce far-red light (maximum emission >700 nm) from suborbital photophores. All three genera are sensitive in this part of the spectrum, to which all other animals of the deep sea are blind, potentially affording them a private waveband for illuminating prey and for interspecific communication that is immune from detection by predators and prey. Aristostomias and Pachystomias enhance their long-wave visual sensitivity by the possession of at least three visual pigments that are long-wave shifted (lambdamax values ca. 515, 550 and 590 nm) compared with those of other deep-sea fishes. Malacosteus, on the other hand, although it does possess two of these red-shifted pigments (lambdamax values ca. 520 and 540 nm), lacks the most long-wave-sensitive pigments found in the other two genera. However, it further enhances its long-wave sensitivity with a chlorophyll-derived photosensitizer within its outer segments. The fluorescence emission and excitation spectra of this pigment are very similar to spectra obtained from mesopelagic copepods, which are an important component of diet of Malacosteus, suggesting a dietary origin for this pigment.

Tone abnormalities are associated with maternal cigarette smoking during pregnancy in in utero cocaine-exposed infants

OBJECTIVE

Maternal cigarette smoking, alcohol use, and other factors confound studies of in utero cocaine exposure. Our goal was to determine whether in utero cocaine exposure is associated with an abnormal neurologic examination in infants, while controlling for concomitant cigarette smoke exposure and other confounding variables.

DESIGN

Healthy newborns with birth weights > or =2000 g were prospectively enrolled into a race-matched study of cocaine-exposed and cocaine-unexposed infants. Urine and meconium samples were analyzed for illicit drugs, the cocaine metabolite, benzoylecgonine, and the nicotine metabolite, cotinine. A detailed neurological examination was performed at approximately 6 weeks of age by an examiner blinded to history.

RESULTS

At 6 weeks of age, 40 cocaine-exposed infants and 56 cocaine-unexposed infants were examined. Tone abnormalities were the only neurologic abnormalities discovered, predominantly generalized hypertonia. Logistic models found that maternal urine cotinine levels were predictive of an abnormal neurologic examination, whereas cocaine exposure or benzoylecgonine levels were not. No interaction was found between maternal cigarette smoking and cocaine exposure. Race, ethanol exposure, prenatal care, homelessness, and head circumference were not predictive of an abnormal tone examination. The odds ratio for an abnormal examination was 2.9 (95% confidence interval: 1.04-8.25), if the maternal urine cotinine level was >200 ng/mL.

CONCLUSION

Our findings suggest that maternal cigarette smoking may be the major predictor of tone abnormalities reported in cocaine-exposed infants.

Visual pigments, cone oil droplets and ocular media in four species of estrildid finch

A microspectrophotometric study was conducted on the retinal photoreceptors of four species of bird: cut-throat finches (Amadina fasciata), gouldian finches (Erythrura gouldiae), white-headed munias (Lonchura maja) and plum-headed finches (Neochmia modesta). Spectral characteristics of the photoreceptors in all four species were very similar. Rods contained a medium-wavelength-sensitive visual pigment with a wavelength of maximum absorbance at 502-504 nm. Four spectrally distinct types of single cone contained a visual pigment with wavelength of maximum absorbance at either 370-373 nm (ultraviolet-sensitive), 440-447 nm (short-wavelength-sensitive); 500 nm (medium-wavelength-sensitive) or 562-565 nm (long-wavelength-sensitive). Oil droplets in the ultraviolet-sensitive single cones showed no detectable absorption between 330 nm and 800 nm. Oil droplets in the short-, medium-, and long-wavelength-sensitive single cones had cut-off wavelengths at 415-423 nm, 510-520 nm and 567-575 nm, respectively. Double cones contained the visual pigment with wavelength of maximum absorbance at 562-565 nm observed in long-wavelength-sensitive single cones. Only the principal member of the double cone pair contained an oil droplet (P-type, cut-off wavelength at 414-489 nm depending on species and retinal location). Spectral transmittance of the intact ocular media of each species was measured along the optic axis. Wavelengths of 0.5 transmittance for all species were very similar (316-318 nm).