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J E Tyson

Publications and source records attributed to J E Tyson.

At least 19 recordsLinked to original sources

Trophic feedings for parenterally fed infants.

BACKGROUND: Because of concern that feedings may increase the risk of necrotizing enterocolitis, some high-risk infants have received prolonged periods of parenteral nutrition without enteral feedings. Providing trophic feedings (small volume feedings given at the same rate for at least 5 days) during this period of parenteral nutrition was developed as a strategy to enhance feeding tolerance and decrease time to reach full feedings. Whether trophic feedings result in better outcomes than initially withholding feedings or providing progressively increasing feedings can be established only in proper clinical trials. OBJECTIVES: 1. For high-risk neonates receiving parenteral feedings, to assess the effect of trophic feeding compared to no enteral nutrient intake on measures of feeding tolerance and neonatal outcome.2. For high-risk neonates receiving parenteral feedings to assess the effect of trophic feedings compared to a specific initial feeding regimen involving a greater enteral nutrient intake on measures of feeding tolerance and neonatal outcome. SEARCH STRATEGY: Searches were performed of MEDLINE (1966 - June 2004), CINAHL (1982 - June 2004), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 3, 2004), abstracts and conference proceedings, references from relevant publications in the English language, and studies identified by personal communication. SELECTION CRITERIA: Only randomized or quasi-randomized clinical trials were considered. Trials were included if they enrolled high-risk infants randomly assigned to receive trophic feedings (defined as dilute or full strength feedings providing < = 25 kcal/kg/d for > = 5d) compared to either 1) no enteral nutrient intake (no feedings or water only) or 2) a specific feeding regimen involving a greater enteral intake of formula or human milk than with trophic feedings. DATA COLLECTION AND ANALYSIS: The two reviewers reached consensus for inclusion of trials. Data regarding clinical outcomes were extracted and evaluated by the two reviewers independently of each other. Authors were contacted as needed and feasible to clarify or provide missing data. The specific data that were needed were requested in writing. MAIN RESULTS: 1. Trophic feedings vs. no feedings (10 trials): Among infants given trophic feedings, there was an overall reduction in days to full feeding (weighted mean difference [WMD] = -2.6 [95% confidence limits = -4.1, -1.0]), total days that feedings were held (WMD = -3.1 [-4.6, -1.6]), and total hospital stay (WMD = -11.4 [-17.2, -5.7] compared to infants given no enteral nutrient intake. Tests for heterogeneity were significant in analyses of days to full enteral feedings, days to regain birth weight, days of phototherapy, and hospital stay. There was no significant difference in necrotizing enterocolitis, although the findings do not exclude an important effect (relative risk = 1.16 [0.75, 1.79]; risk difference = 0.02 [-0.03, 0.06].2. Trophic feedings vs. advancing feedings (one trial): Infants given trophic feedings required more days to reach full enteral feeding (13.4 [8.2, 18.6]) and tended to have a longer hospital stay (11.0 [-1.4, 23.4]) than did infants given advancing feedings. With only eight total cases of necrotizing enterocolitis, trophic feedings were associated with a marginally significant reduction in necrotizing enterocolitis (relative risk =0.14 [0.02, 1.07]; risk difference = -0.09 [-0.16, -0.01]. AUTHORS' CONCLUSIONS: In both comparisons, the group with the greater enteral intake (trophic feedings in the first comparison and advancing feedings in the second comparison) required significantly less time to reach full feedings and had a significant or near significant reduction in hospital stay. In both comparisons, the group with the greater intake also had a higher incidence of necrotizing enterocolitis although the difference was not statistically significant. The concern is greatest for the advancing feeding regimen. Even when trophic feedings were compared to no feedings, the relative risk for necrotizing enterocolitis was 1.16 (0.75 - 1.79), a finding consistent with a 16% increase in necrotizing enterocolitis and a number needed to harm of 50. A true increase of this magnitude might outweigh any short- or long-term benefits of trophic feedings. Moreover, the 95% confidence interval does not exclude the possibility that trophic feedings increase necrotizing enterocolitis by as much as 79% with a number needed to harm of 17. Whether no feedings, trophic feedings, or advancing feedings should initially be used is difficult to discern for a variety of reasons--the inherent difficulty of assessing enteral feedings in high-risk infants, the limited sample size and methodologic limitations of most studies to date, unexplained heterogeneity with respect to a number of outcomes, the potential for bias to affect the findings in unblinded studies, and the large number of infants who must be studied to assess the effect on necrotizing enterocolitis. One or more large, well designed, multi-center trials are needed to compare these approaches to early feeding with respect to important clinical outcomes. A conclusive evaluation would assess effects on not only the survival rate without necrotizing enterocolitis prior to discharge from the neonatal unit but also on the survival rate without severe gastrointestinal or neurodevelopmental disability at >= 18 months age.

Enteral Nutrition↗

Risk factors for neonatal seizures: a population-based study, Harris County, Texas, 1992-1994.

Risk factors for neonatal seizures were evaluated in 116,048 infants born between 1992 and 1994 to residents of Harris County, Texas; 207 of these infants were diagnosed with clinical neonatal seizures. Information was obtained from the infant's birth certificate to assess the relation between seizures and birth weight, gender, ethnicity, place of birth, mother's age, method of delivery, parity, and multiple births. These factors were evaluated by univariate and multivariate analysis using logistic regression. For preterm infants, a birth weight of <1,500 g was the strongest risk factor (relative risk (RR) = 9.1, 95% confidence interval (CI): 4.7, 17.5), followed by birth in a private/university hospital (RR = 2.8, 95% CI: 1.5, 5.0) and male gender (RR = 1.8, 95% CI: 1.0, 3.4). For term infants, significant risk factors included birth by cesarean section (RR = 2.2, 95% CI: 1.5, 3.2), small birth weight for gestational age (RR = 1.9, 95% CI: 1.2, 2.9), birth in a private/university hospital (RR = 1.8, 95% CI: 1.1, 3.0), and maternal age of 18-24 compared with 25-29 years (RR = 1.6, 95% CI: 1.1, 2.3). Birth by assisted vaginal delivery and primiparity were marginally significant for term infants. Birth weight is a significant risk factor for neonatal seizures. The role of perinatal complications warrants further evaluation.

Birth Weight↗

Adverse effects of early dexamethasone treatment in extremely-low-birth-weight infants. National Institute of Child Health and Human Development Neonatal Research Network.

BACKGROUND: Early administration of high doses of dexamethasone may reduce the risk of chronic lung disease in premature infants but can cause complications. Whether moderate doses would be as effective but safer is not known. METHODS: We randomly assigned 220 infants with a birth weight of 501 to 1000 g who were treated with mechanical ventilation within 12 hours after birth to receive dexamethasone or placebo with either routine ventilatory support or permissive hypercapnia. The dexamethasone was administered within 24 hours after birth at a dose of 0.15 mg per kilogram of body weight per day for three days, followed by a tapering of the dose over a period of seven days. The primary outcome was death or chronic lung disease at 36 weeks' postmenstrual age. RESULTS: The relative risk of death or chronic lung disease in the dexamethasone-treated infants, as compared with those who received placebo, was 0.9 (95 percent confidence interval, 0.8 to 1.1). Since the effect of dexamethasone treatment did not vary according to the ventilatory approach, the two dexamethasone groups and the two placebo groups were combined. The infants in the dexamethasone group were less likely than those in the placebo group to be receiving oxygen supplementation 28 days after birth (P=0.004) or open-label dexamethasone (P=0.01), were more likely to have hypertension (P<0.001), and were more likely to be receiving insulin treatment for hyperglycemia (P=0.02). During the first 14 days, spontaneous gastrointestinal perforation occurred in a larger proportion of infants in the dexamethasone group (13 percent, vs. 4 percent in the placebo group; P=0.02). The dexamethasone-treated infants had a lower weight (P=0.02) and a smaller head circumference (P=0.04) at 36 weeks' postmenstrual age. CONCLUSIONS: In preterm infants, early administration of dexamethasone at a moderate dose has no effect on death or chronic lung disease and is associated with gastrointestinal perforation and decreased growth.

Anti-Inflammatory Agents↗

Very low birth weight outcomes of the National Institute of Child health and human development neonatal research network, January 1995 through December 1996. NICHD Neonatal Research Network.

OBJECTIVES: To determine the mortality and morbidity for infants weighing 401 to 1500 g (very low birth weight [VLBW]) at birth by gestational age, birth weight, and gender. STUDY DESIGN: Perinatal data were collected prospectively on an inborn cohort from January 1995 through December 1996 by 14 participating centers of the National Institute of Child Health and Human Development Neonatal Research Network and were compared with the corresponding data from previous reports. Sociodemographic factors, perinatal events, and the neonatal course to 120 days of life, discharge, or death were evaluated. RESULTS: Eighty four percent of 4438 infants weighing 501 to 1500 g at birth survived until discharge to home or to a long-term care facility (compared with 80% in 1991 and 74% in 1988). Survival to discharge was 54% for infants 501 to 750 g at birth, 86% for those 751 to 1000 g, 94% for those 1001 to 1250 g, and 97% for those 1251 to 1500g. The incidence of chronic lung disease (CLD; defined as receiving supplemental oxygen at 36 weeks' postmenstrual age; 23%), proven necrotizing enterocolitis (NEC; 7%), and severe intracranial hemorrhage (ICH; grade III or IV; 11%) remained unchanged between 1991 and 1996. Furthermore, 97% of all VLBW infants and 99% of infants weighing <1000 g at birth had weights less than the 10th percentile at 36 weeks' postmenstrual age. Mortality for 195 infants weighing 401 to 500 g was 89%, with nearly all survivors developing CLD. Mortality in infants weighing 501 to 600 g was 71%; among survivors, 62% had CLD, 35% had severe ICH, and 15% had proven NEC. CONCLUSIONS: Survival for infants between 501 and 1500 g at birth continued to improve, particularly for infants weighing <1000 g at birth. This improvement in survival was not associated with an increase in major morbidities, because the incidence of CLD, proven NEC, and severe ICH did not change. However, poor postnatal growth remains a major concern, occurring in 99% of infants weighing <1000 g at birth. Mortality and major morbidity (CLD, severe ICH, and NEC) remain high for the smallest infants, particularly those weighing <600 g at birth.

Adult↗

Comparison of management strategies for extreme prematurity in New Jersey and the Netherlands: outcomes and resource expenditure.

OBJECTIVE: To quantify differences in resource expenditure in the perinatal period and long-term outcome of extremely premature infants who received systematically different approaches to neonatal intensive care. METHODS: Perinatal management, mortality, prevalence of disabling cerebral palsy (DCP), and resource expenditure of 2 population-based inception cohorts of extremely premature infants born in the mid-1980s were compared. Electronic fetal monitoring, tocolysis, cesarean section delivery, and assisted ventilation were used to characterize management approaches. Participants included all live births at 23 to 26 weeks' gestation in a 3-county area of central New Jersey (NJ) from 1984 to 1987 (N = 146) and throughout the Netherlands (NETH) in 1983 (N = 142). Mortality and the prevalence of DCP were the primary outcomes. Numbers of hospital days with and without assisted ventilation were the measures of resource expenditure. RESULTS: Electronic fetal monitoring (100% vs 38%), cesarean section (28% vs 6%), and assisted ventilation (95% vs 64%) were all more commonly used in NJ than in NETH. Ten percent of NJ deaths occurred without assisted ventilation, compared with 45% of Dutch deaths. A total of 1820 ventilator days were expended per 100 live births in NJ, compared with 448 in NETH. The increase in the number of nonventilator days (3174 vs 2265 days per 100 live births) did not reach statistical significance. Survival to age 2 (46 vs 22%) and the prevalence of DCP among survivors (17.2 vs 3.4%) were significantly greater in NJ at age 2 than in NETH at age 5. CONCLUSIONS: Near universal initiation of intensive care in NJ, compared with selective initiation of intensive care in NETH, was associated with 24.1 additional survivors per 100 live births, 7.2 additional cases of DCP per 100 live births, and a cost of 1372 additional ventilator days per 100 live births.

Analysis of Variance↗

Comprehensive follow-up care and life-threatening illnesses among high-risk infants: A randomized controlled trial.

CONTEXT: Inner-city high-risk infants often receive limited and fragmented care, a problem that may increase serious illness. OBJECTIVE: To assess whether access to comprehensive care in a follow-up clinic is cost-effective in reducing life-threatening illnesses among high-risk, inner-city infants. DESIGN: Randomized controlled trial. SETTING AND PARTICIPANTS: A total of 887 very-low-birth-weight infants born in a Texas county hospital between January 1988 and March 1996 and followed up in a children's hospital clinic. One hundred four infants who became ineligible or died after randomization but before nursery discharge were excluded from the analysis. INTERVENTIONS: Infants were randomly assigned to receive routine follow-up care (well-baby care and care for chronic illnesses; n = 441) or comprehensive care (which included the components of routine care plus care for acute illnesses, with 24-hour access to a primary caregiver; n = 446). MAIN OUTCOME MEASURES: Life-threatening illnesses (ie, causing death or hospital admission for pediatric intensive care) occurring between nursery discharge and age 1 year, assessed by blinded evaluators from inpatient charts and state Medicaid and vital statistics records; and hospital costs (estimated from department-specific cost-to-charge ratios). RESULTS: Comprehensive care resulted in a mean of 3.1 more clinic visits and 6.7 more telephone conversations with clinic staff (P<.001 for both). One-year outcomes were unknown for fewer comprehensive-care infants than routine-care infants (9 vs 28; P =.001). Identified deaths were similar (11 in comprehensive care vs 13 in routine care; P =.68). The comprehensive-care group had 48% fewer life-threatening illnesses (33 vs 63; P<.001), 57% fewer intensive care admissions (23 vs 53; P =.003), and 42% fewer intensive care days (254 vs 440; P =.003). Comprehensive care did not increase the mean estimated cost per infant for all care ($6265 with comprehensive care and $9913 with routine care). CONCLUSION: Comprehensive follow-up care by experienced caregivers can be highly effective in reducing life-threatening illness without increasing costs among high-risk inner-city infants. JAMA. 2000;284:2070-2076.

Acute Disease↗

Minimal enteral nutrition for promoting feeding tolerance and preventing morbidity in parenterally fed infants.

BACKGROUND: Because of concern that feedings may increase the risk of necrotizing enterocolitis, some high-risk infants have received prolonged periods of parenteral nutrition without enteral feedings. Providing minimal enteral feedings during this period of parenteral nutrition was developed as a strategy to enhance feeding tolerance and decrease time to reach full feedings. OBJECTIVES: For high-risk neonates receiving parenteral feedings, to assess the effect of minimal enteral nutrition (MEN) compared to no enteral nutrient intake on measures of feeding tolerance and neonatal outcome. SEARCH STRATEGY: Searches were performed of the Oxford Database of Perinatal Trials, MEDLINE, abstracts and conference proceedings, references from relevant publications in the English language, and studies identified by personal communication. SELECTION CRITERIA: Only randomized or quasi-randomized clinical trials were considered. Trials were included if they enrolled high-risk infants randomly assigned to receive minimal enteral feedings (defined as dilute or full strength feedings providing <= 25 kcal/kg/d for >= 5d) or no enteral nutrient intake (no feedings or water only). DATA COLLECTION AND ANALYSIS: The two reviewers reached consensus for inclusion of trials. Data regarding clinical outcomes were extracted and evaluated by the two reviewers independently of each other. Authors were contacted as needed and feasible to clarify or provide missing data. The specific data that were needed were requested in writing. MAIN RESULTS: Among infants given minimal enteral nutrition (MEN), there was an overall reduction in days to full enteral feeding, total days that feedings were held, and total hospital stay. There was no discernible effect on necrotizing enterocolitis. REVIEWER'S CONCLUSIONS: The evidence of benefit from MEN in these analyses is not convincing for a variety of reasons--the inherent difficulty of assessing enteral feedings in high-risk infants, the small size and methodologic limitations of the studies to date, unexplained heterogeneity with respect to some of the apparent benefits, the potential for bias to affect the findings in unblinded studies, and the unexcluded possibility that MEN might increase necrotizing enterocolitis. For these reasons, it is unclear whether MEN should be used in lieu of an equal period of time without enteral feedings.

Enteral Nutrition↗

Rapid versus slow rate of advancement of feedings for promoting growth and preventing necrotizing enterocolitis in parenterally fed low-birth-weight infants.

BACKGROUND: Very premature infants fed by gavage are unable to regulate their own enteral intake. Therefore the rate at which feedings are advanced must be determined by caregivers. While advancing feedings too rapidly may increase the risk of necrotizing enterocolitis, advancing feedings too slowly might result in undernutrition or prolonged hospital stay. OBJECTIVES: For low-birth-weight premature infants receiving parenteral fluids, to assess the effect of different rates of advancement of enteral feedings beginning at the same age on measures of feeding tolerance and neonatal outcome. SEARCH STRATEGY: Search strategies included a Medline search and a search of the Oxford Database of Perinatal Trials; additional references were sought in review articles, relevant chapters of textbooks, a previous systematic review, recent American Pediatric Society - Society for Pediatric Research abstracts, personal files, and personal communication. SELECTION CRITERIA: Only randomized or quasi-randomized trials were considered. Trials were included if premature low-birth-weight infants were studied and if the strategies being compared were different rates of advancement of feedings (accomplished by either differences in volume or concentration) with the onset of feedings at the same postnatal age in each group. DATA COLLECTION AND ANALYSIS: The two reviewers reached consensus for inclusion of trials. Data regarding clinical outcomes were extracted and evaluated by the two reviewers independently of each other. Authors were contacted as needed and feasible to clarify or provide missing data. The specific data that were needed were requested in writing. MAIN RESULTS: Among infants randomized to more rapid rates of advancement of feedings, there was an overall reduction in days to full enteral feeding and days to regain birth weight. There was no effect on necrotizing enterocolitis (relative risk = 0.90, 95% confidence interval = 0. 46-1.77). REVIEWER'S CONCLUSIONS: There are suggested advantages of more rapid rates of advancing feedings in premature low-birth-weight infants (shorter time to regain birth weight and shorter time to achieve full feedings). It is unclear whether this strategy should be adopted as routine practice because of limited information regarding safety (broad confidence intervals for the incidence of necrotizing enterocolitis) and the effect on length of hospital stay (broad confidence intervals). Because different birth weight ranges and different rates of advancement were used in each of these studies, the ideal rate of advancement remains unclear, particularly for extremely-low-birth-weight infants.

Enteral Nutrition↗

Early versus delayed initiation of progressive enteral feedings for parenterally fed low birth weight or preterm infants.

BACKGROUND: Enteral feedings in very-low-birth-weight or sick preterm infants are often delayed for several days or weeks after birth even though delayed enteral feeding could diminish the functional adaptation of the gastrointestinal tract and result in feeding intolerance later. Early initiation of feedings, if well-tolerated, may promote growth and shorten the duration of parenteral nutrition and hospital stay without increasing the risk for necrotizing enterocolitis (NEC). OBJECTIVES: For parenterally fed low-birth-weight infants, to assess the effects of early enteral feedings initiated shortly after birth compared to delayed enteral feedings (with similar schedules for advancing feedings in each group). SEARCH STRATEGY: Searches were performed of the Oxford Database of Perinatal Trials, the Cochrane Neonatal Review Group registry, MEDLINE, abstracts and conference proceedings, references from relevant publications in the English language, and studies identified by personal communication. SELECTION CRITERIA: Only randomized or quasi-randomized clinical trials were considered. Trials were included if 1) they enrolled low birth weight or preterm infants who were all given parenteral nutrition; 2) the infants were randomly assigned to either early enteral feedings (mean or median age <=4 days) or late enteral feedings (>4 days) of formula or breast milk; 3) except when feeding intolerance developed, the feedings were progressively advanced starting within 72 hours after initiating feedings; and 4) the goals for total nutrient intake were similar for both groups. (We did not require the duration or total intake of parenteral nutrients to be similar for both groups because these variables may be affected by the age at which feedings are initiated.) DATA COLLECTION AND ANALYSIS: The two reviewers reached consensus for inclusion of trials. Data regarding clinical outcomes were extracted and evaluated by two reviewers (JET and KAK) independently. Authors were contacted as needed and feasible to clarify or provide missing data. The specific data that were needed were requested in writing and by telephone. MAIN RESULTS: Only two small studies were identified (one with 60 patients and one with 12 patients). Five randomized trials were excluded because parenteral nutrition was not provided or because the groups were assigned to receive different parenteral intakes as well as different enteral intakes. An additional unpublished small trial was excluded because both groups were fed "late" according to our categorization. Because there were no clinical outcomes which were reported in both of the included studies, no meta analysis of the results was performed. Based on the results of the individual studies, early feedings had no significant effect on weight gain, necrotizing enterocolitis, mortality, or age at discharge, although important effects cannot be excluded with the small number of patients studied. Some benefits of early feedings were noted in the larger trial (Davey) -- fewer days on parenteral nutrition, fewer infants who were treated with gastric suction and interruption of feedings, fewer infants with sepsis evaluations, and fewer infants with percutaneous central venous catheters. REVIEWER'S CONCLUSIONS: The benefits and hazards of early and delayed feedings have received very little study in clinical trials, and the effects on major clinical outcomes, including necrotizing enterocolitis and death, remain uncertain. With the availability of parenteral nutrition in contemporary neonatal units, it is unclear whether high-risk infants should receive early or delayed feedings.

Enteral Nutrition↗

Sex differences in outcomes of very low birthweight infants: the newborn male disadvantage.

OBJECTIVE: To determine the differences in short term outcome of very low birthweight infants attributable to sex. METHODS: Boys and girls weighing 501-1500 g admitted to the 12 centres of the National Institute of Child Health and Human Development Neonatal Research Network were compared. Maternal information and perinatal data were collected from hospital records. Infant outcome was recorded at discharge, at 120 days of age if the infant was still in hospital, or at death. Best obstetric estimate based on the last menstrual period, standard obstetric factors, and ultrasound were used to assign gestational age in completed weeks. Data were collected on a cohort that included 3356 boys and 3382 girls, representing all inborn births from 1 May 1991 to 31 December 1993. RESULTS: Mortality for boys was 22% and that for girls 15%. The prenatal and perinatal data indicate few differences between the sex groups, except that boys were less likely to have been exposed to antenatal steroids (odds ratio (OR) = 0.80) and were less stable after birth, as reflected in a higher percentage with lower Apgar scores at one and five minutes and the need for physical and pharmacological assistance. In particular, boys were more likely to have been intubated (OR = 1.16) and to have received resuscitation medication (OR = 1.40). Boys had a higher risk (OR > 1.00) for most adverse neonatal outcomes. Although pulmonary morbidity predominated, intracranial haemorrhage and urinary tract infection were also more common. CONCLUSIONS: Relative differences in short term morbidity and mortality persist between the sexes.

Apgar Score↗

Persistent pulmonary hypertension of the newborn in the era before nitric oxide: practice variation and outcomes.

OBJECTIVES: In the era before widespread use of inhaled nitric oxide, to determine the prevalence of persistent pulmonary hypertension (PPHN) in a multicenter cohort, demographic descriptors of the population, treatments used, the outcomes of those treatments, and variation in practice among centers. STUDY DESIGN: A total of 385 neonates who received >/=50% inspired oxygen and/or mechanical ventilation and had documented evidence of PPHN (2D echocardiogram or preductal or postductal oxygen difference) were tracked from admission at 12 Level III neonatal intensive care units. Demographics, treatments, and outcomes were documented. RESULTS: The prevalence of PPHN was 1.9 per 1000 live births (based on 71 558 inborns) with a wide variation observed among centers (.43-6.82 per 1000 live births). Neonates with PPHN were admitted to the Level III neonatal intensive care units at a mean of 12 hours of age (standard deviation: 19 hours). Wide variations in the use of all treatments studied were found at the centers. Hyperventilation was used in 65% overall but centers ranged from 33% to 92%, and continuous infusion of alkali was used in 75% overall, with a range of 27% to 93% of neonates. Other frequently used treatments included sedation (94%; range: 77%-100%), paralysis (73%; range: 33%-98%), and inotrope administration (84%; range: 46%-100%). Vasodilator drugs, primarily tolazoline, were used in 39% (range: 13%-81%) of neonates. Despite the wide variation in practice, there was no significant difference in mortality among centers. Mortality was 11% (range: 4%-33%). No specific therapy was clearly associated with a reduction in mortality. To determine whether the therapies were equivalent, neonates treated with hyperventilation were compared with those treated with alkali infusion. Hyperventilation reduced the risk of extracorporeal membrane oxygenation without increasing the use of oxygen at 28 days of age. In contrast, the use of alkali infusion was associated with increased use of extracorporeal membrane oxygenation (odds ratio: 5.03, compared with those treated with hyperventilation) and an increased use of oxygen at 28 days of age. CONCLUSIONS: Hyperventilation and alkali infusion are not equivalent in their outcomes in neonates with PPHN. Randomized trials are needed to evaluate the role of these common therapies.

Administration, Inhalation↗

Incidence of neonatal seizures in Harris County, Texas, 1992-1994.

This study estimated the incidence of clinical neonatal seizures among infants born between 1992 and 1994 in Harris County, Texas, a county with a large and ethnically diverse population. Infants with neonatal seizures were ascertained from four sources: hospital discharge diagnoses, birth certificates, death certificates, and a study of neonatal seizures conducted concurrently with this study at a large tertiary care center in Houston, Texas. There were 207 cases of clinical neonatal seizures among 116,048 live births (an incidence of 1.8 per 1,000 live births). The incidence was highest among infants weighing less than 1,500 g (19/1,000) and decreased as birth weight increased. There was no significant difference in incidence by ethnicity. Twenty-six percent of the seizures (54/207) occurred after the infants had been discharged from the hospital where they were born. The incidence of neonatal seizures in Harris County was lower than the incidence reported recently for Fayette County, Kentucky, for 1985-1989 (3.5/1,000) and for Newfoundland, Canada, for 1990-1995 (2.5/1,000), but was higher than the incidence estimated for Rochester, Minnesota, for 1935-1984 (1/1,000).

Age Factors↗

Vitamin A supplementation for extremely-low-birth-weight infants. National Institute of Child Health and Human Development Neonatal Research Network.

BACKGROUND: Vitamin A supplementation may reduce the risk of chronic lung disease and sepsis in extremely-low-birth-weight infants. The results of our pilot study suggested that a dose of 5000 IU administered intramuscularly three times per week for four weeks was more effective than the lower doses given in past trials. METHODS: We performed a multicenter, blinded, randomized trial to assess the effectiveness and safety of this regimen as compared with sham treatment in 807 infants in need of respiratory support 24 hours after birth. The mean birth weight was 770 g in the vitamin A group and 769 g in the control group, and the respective gestational ages were 26.8 and 26.7 weeks. RESULTS: By 36 weeks' postmenstrual age, 59 of the 405 infants (15 percent) in the vitamin A group and 55 of the 402 infants (14 percent) in the control group had died. The primary outcome - death or chronic lung disease at 36 weeks' postmenstrual age - occurred in significantly fewer infants in the vitamin A group than in the control group (55 percent vs. 62 percent; relative risk, 0.89; 95 percent confidence interval, 0.80 to 0.99). Overall, 1 additional infant survived without chronic lung disease for every 14 to 15 infants who received vitamin A supplements. The proportions of infants in the vitamin A group and the control group who had signs of potential vitamin A toxicity were similar. The proportion of infants with serum retinol values below 20 microg per deciliter (0.70 micromol per liter) was lower in the vitamin A group than in the control group (25 percent vs. 54 percent, P<0.001). CONCLUSIONS: Intramuscular administration of 5000 IU of vitamin A three times per week for four weeks reduced biochemical evidence of vitamin A deficiency and slightly decreased the risk of chronic lung disease in extremely-low-birth-weight infants.

Chronic Disease↗

Inaccuracy of Ballard scores before 28 weeks' gestation. National Institute of Child Health and Human Development Neonatal Research Network.

OBJECTIVE: Ballard scores are commonly used to estimate gestational age (GA). The purpose of this study was to determine the accuracy of the New Ballard Score (NBS) for infants <28 weeks GA by accurate menstrual history and to evaluate NBS as an outcome predictor. METHODS: Infants weighing 401 to 1500 g in 12 National Institute of Child Health and Human Development Neonatal Research Network centers had NBS performed before age 48 hours. Accuracy of NBS estimates of GA was assessed for infants with GA determined by accurate menstrual history. In a larger cohort of infants, NBS was included in regression models of the association of NBS and death, poor outcome, and duration of hospital stay. RESULTS: At each week from 22 to 28 weeks GA by accurate menstrual history, NBS estimates exceeded GA by dates by 1.3 to 3.3 weeks, and estimates varied widely (range of widths of 95% CIs for the observations, 6.8 to 11.9 weeks). NBS did not contribute significantly to regression models of death, poor outcome, or duration of hospital stay. CONCLUSIONS: Inaccuracies in GA determined by the NBS should be considered when treating extremely premature infants, particularly in decisions to forego or administer intensive care. Refinement of GA scoring systems is needed to optimize clinical benefit.

Female↗

Longitudinal growth of hospitalized very low birth weight infants.

BACKGROUND: The interpretation of growth rates for very low birth weight infants is obscured by limited data, recent changes in perinatal care, and the uncertain effects of multiple therapies. OBJECTIVES: To develop contemporary postnatal growth curves for very low birth weight preterm infants and to relate growth velocity to birth weight, nutritional practices, fetal growth status (small- or appropriate-for-gestational-age), and major neonatal morbidities (chronic lung disease, nosocomial infection or late-onset infection, severe intraventricular hemorrhage, and necrotizing enterocolitis). DESIGN: Large, multicenter, prospective cohort study. METHODS: Growth was prospectively assessed for 1660 infants with birth weights between 501 to 1500 g admitted by 24 hours of age to 1 of the 12 National Institute of Child Health and Human Development Neonatal Research Network centers between August 31, 1994 and August 9, 1995. Infants were included if they survived >7 days (168 hours) and were free of major congenital anomalies. Anthropometric measures (body weight, length, head circumference, and midarm circumference) were performed from birth until discharge, transfer, death, age 120 days, or a body weight of 2000 g. To obtain representative data, nutritional practices were not altered by the study protocol. RESULTS: Postnatal growth curves suitable for clinical and research use were constructed for body weight, length, head circumference, and midarm circumference. Once birth weight was regained, weight gain (14.4-16.1 g/kg/d) approximated intrauterine rates. However, at hospital discharge, most infants born between 24 and 29 weeks of gestation had not achieved the median birth weight of the reference fetus at the same postmenstrual age. Gestational age, race, and gender had no effect on growth within 100-g birth weight strata. Appropriate-for-gestational age infants who survived to hospital discharge without developing chronic lung disease, severe intraventricular hemorrhage, necrotizing enterocolitis, or late onset-sepsis gained weight faster than comparable infants with those morbidities. More rapid weight gain was also associated with a shorter duration of parenteral nutrition providing at least 75% of the total daily fluid volume, an earlier age at the initiation of enteral feedings, and an earlier age at achievement of full enteral feedings. CONCLUSIONS: These growth curves may be used to better understand postnatal growth, to help identify infants developing illnesses affecting growth, and to aid in the design of future research. They should not be taken as optimal. Randomized clinical trials should be performed to evaluate whether different nutritional management practices will permit birth weight to be regained earlier and result in more rapid growth, more appropriate body composition, and improved short- and long-term outcomes.

Anthropometry↗

Dexamethasone therapy increases infection in very low birth weight infants.

BACKGROUND: Infection is a major complication of preterm infants, resulting in increased morbidity and mortality. We recently reported the results of a multicenter trial of dexamethasone initiated at 14 or 28 days in very low birth weight (VLBW) infants who were at risk for chronic lung disease; the results showed an increase in nosocomial bacteremia in the group receiving dexamethasone. This study is an in-depth analysis of bacteremia/sepsis and meningitis among infants enrolled in the trial. METHODS: Data on cultures performed and antibiotic therapy were collected prospectively. Infections were classified as definite or possible/clinical. RESULTS: A total of 371 infants were enrolled in the trial. There were no baseline differences in risk factors for infection. For the first 14 days of study, infants received either dexamethasone (group I, 182) or placebo (group II, 189). During this period, infants in group I were significantly more likely than those in group II to have a positive blood culture result (48% vs 30%) and definite bacteremia/sepsis/meningitis (22% vs 14%). Over the 6-week study period, 47% of those cultured had at least one positive blood culture result (53% in group I vs 41% in group II) and 25% of the infants had at least one episode of definite bacteremia/sepsis/meningitis (29% in group I vs 21% in group II). Among infants with definite infections, 46.8% were attributable to Gram-positive organisms, 26.6% to Gram-negative organisms and 26.6% to fungi. The factors present at randomization were evaluated for their association with infection. Group I assignment and H(2) blocker therapy (before study entry) were associated with increased risk of definite infection, whereas cesarean section delivery and increasing birth weight were associated with decreased risk. CONCLUSIONS: Infants who received a 14-day course of dexamethasone initiated at 2 weeks of age were more likely to develop a bloodstream or cerebrospinal fluid infection while on dexamethasone therapy than were those who received placebo. Physicians must consider this increased risk of infection when deciding whether to treat VLBW infants with dexamethasone.

Cross Infection↗