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Dieldrin and DDx removal through wastewater treatment, ozonation, and microfiltration was assessed for a water reuse project for groundwater replenishment in Monterey, California, USA. Full-scale sampling was conducted at the wastewater treatment plant, and physical wastewater treatment processes, ozonation, and microfiltration were tested at the bench scale. Removals observed through wastewater treatment, ozonation, and microfiltration were 84%, 44% to 63%, and 97% to 98%, respectively, for dieldrin, and 93%, 36% to 48%, and 92% to 94% for DDx. These were sufficient to meet California Ocean Plan water quality objectives after wastewater treatment alone. Levels in the secondary effluent, ahead of ozonation, microfiltration, reverse osmosis and advanced oxidation in the advanced water purification facility, met drinking water standards. Removal of dieldrin and DDx through wastewater treatment occurred by physical treatment processes; removal through the full-scale wastewater treatment plant, which included biological and physical treatment processes, matched removal through the physical bench-scale wastewater treatment processes. Dieldrin and DDx removal correlated with removal of volatile suspended solids, suggesting that volatile suspended solids could be used as an indicator for pesticide removal through wastewater treatment. Dieldrin and DDx concentrations were highest in the solids contact process, where biomass is accumulated for carbon removal. [ABSTRACT FROM AUTHOR]

Thirty nine very low birthweight neonates (with a birth weight of 820 to 1500 g and gestation of 27 to 34 weeks) who required total parenteral nutrition were randomly assigned to one of three regimens of administration of fat emulsion for a period of eight days. Groups 1 and 2 received the emulsion at a constant rate over 24 and 16 hours, respectively, beginning with a daily dosage of 1 g/kg and increasing daily by 1 g/kg to a maximum of 4 g/kg. Group 3 received the emulsion at a constant rate of 4 g/kg a day over 24 hours. Plasma concentrations of free fatty acids and serum concentrations of total bilirubin, apparent unbound bilirubin, and albumin were measured at regular intervals. Effects of the three regimens on serum bilirubin measurements were determined. The regimen of fat infusion and rate of infusion seemed to have no effect on serum concentrations of total and apparent unbound bilirubin, although there was a trend towards greater variability in apparent unbound concentrations with the intermittent regimen. [ABSTRACT FROM AUTHOR]

The effect of postnatal age on serum bilirubin binding measurements was studied prospectively in extremely premature infants of 25-28 weeks' gestation. Serum was obtained from 10 infants at birth, 2-4 days of age, 1 week, 2 weeks, 4 weeks, 8 weeks, and 10-13 weeks. Using peroxidase oxidation, the apparent unbound bilirubin concentration (AUBC) was measured and plotted versus the molar ratio of total bilirubin:albumin (R) using the empiric power curve AUBC = aRb. The apparent unbound bilirubin concentration at bilirubin:albumin ratio 0.6 was used to compare relative binding ability among specimens. This value, as well as the apparent association constants, showed dramatic deterioration after birth, which persisted without improvement until 8 weeks of age. This pattern of recovery correlated in general with the resolution of clinical problems. Binding values equivalent to adult serum were achieved by 10-13 weeks. This study emphasises that diminished bilirubin binding by the sera of premature infants can persist for a prolonged period. [ABSTRACT FROM AUTHOR]

It has been suggested that the serum of infants with ABO hemolytic disease contains hematin which might interfere with bilirubin binding to albumin, increasing the risk of kerincterus. Using the horseradish peroxidase assay, we investigated this possibility. Cord serum from healthy term infants was enriched with bilirubin to a bilirubin/albumin molar ratio of 0.6, and then varying amounts of hematin were added. Hematin had a significant adverse effect on bilirubin binding when present in half to equimolar ratios with bilirubin. This high concentration of hematin does not appear to be present in serum from infants with ABO hemolytic disease and no difference was seen when comparing the dilute and the undilute peroxidase assays. These data suggest that hematin can alter bilirubin binding in neonatal serum but is not os physiologic importance for infants with ABO-isoimmune hemolysis.

Sixty-two high-risk acidemic premature newborn infants, given maintenance intravascular infusions of 10% glucose, were assigned to liberal or restricted sodium bicarbonate treatment groups. Those infants in the liberal group received 5 to 15 mEq bicarbonate/dl 10% glucose, depending on the degree of acidosis. Among infants given bicarbonate, correction of pH was not more rapid and mortality was not decreased. Instead, there was a small increase in the number of deaths, but the incidence of intraventricular hemorrhage was similar to that in infants not given bicarbonate.

The effect of gestational age on bilirubin binding was studied using cord serum from 22 preterm infants and 13 term infants and serum from 17 adults. Using the peroxidase oxidation method, a bilirubin titration curve was obtained by adding bilirubin to serum and measuring the apparent unbound bilirubin concentration. The resultant curve was analyzed using the least-squares fit of the empiric equation Y = aXb. After correction for albumin concentration by plotting the apparent unbound bilirubin concentration against the molar ratio of total bilirubin/albumin, term and preterm infants had identical titration curves, which remained inferior to that of adults. In addition, the apparent primary bilirubin association constant Ka'1 was similar for all infants but was two to three times less than that for adults. We conclude that bilirubin binding by cord serum is equivalent regardless of gestational age. However, adult serum binds bilirubin qualitatively better than does serum from infants of all gestational ages. We suggest that the adverse effect of prematurity on bilirubin binding noted in previous studies may have reflected postnatal complications rather than gestational age as such.

The primary objective of this study was the establishment of a postnatal growth curve for the very low-birth-weight infant. Only infants whose size was appropriate for gestational age and whose predominant form of nourishment was enteral were included in the study. Two growth curves were constructed: one for infants weighing less than 900 g (group A, birth weight 799 +/- 79 [SD] g, mean gestational age 26.5 weeks), and one for infants weighing 901 to 1,100 g (group B, birth weight 1,023 +/- 53 [SD] g, mean gestational age 28.5 weeks). Growth was followed over the first 50 postnatal days. Group A infants gained an average of 10.2 g/d overall during the first 50 postnatal days and group B infants gained an average of 17.1 g/d over the same period. Because the major objective of this study was construction of a growth curve for infants weighing less than 900 g, direct comparison is made with the Dancis grid (1948) as this is the only standard for this group. The growth rates of our infants were found to be more than twice that of the original prediction of Dancis.

We used Guttman scaling procedures to devise a quantitative, reproducible measure among pediatric residents of attitude change concerning neonatal resuscitation. Preliminary cross-sectional testing of an incoming group of pediatric level 1 residents and graduating pediatric level 3 residents indicated that pediatric level 3 residents were more reluctant to resuscitate high-risk infants. This reluctance was not due to age differences. The pediatric level 1 residents were retested at the completion of each year of training. Residents showed significantly increased reluctance to resuscitate infants at the end of the first year of training and again at the end of the third year of training. These attitude changes were unrelated to gender, marital status, religious preference, or ethnic background. Data acquired both cross-sectionally and longitudinally indicated that attitudes toward neonatal resuscitation changed during residency training.

A self-administered questionnaire concerning various neonatal ethical issues was completed by 39 ICU and 36 intermediate care unit (INT) nurses. Guttman scale analysis indicated that ICU nurses were more reluctant than INT nurses to resuscitate certain high-risk newborn infants. Work experience and a stated religious preference accentuated an INT nurse's disinclination to resuscitate high-risk babies. ICU nurses were more likely than INT nurses to favor passive and active euthanasia. Further, ICU nurses were more likely than INT nurses to view termination of life support for a sick infant as a necessity. ICU nurses were less likely than INT nurses to favor physician intervention in the care of all acutely sick neonates. ICU and INT nurses agreed, however, that the decision to terminate a baby's life support should be made jointly by the child's parents and physicians. Although differences in ICU and INT nursing attitudes may reflect quantitative and qualitative differences in work experience, these findings suggest a common need for emotional support and continuing education programs for nurses who care for high-risk newborns.

To test the hypothesis that intarpartum acidosis has a role in the etiology of hyaline membrane disease (HMD), blood was collected from the umbilical artery (UA) at birth from 110 premature infants and analyzed for hydrogen ion concentration ([H+]), PCO2, standard bicarbonate, and lactic acid. The infants were followed until a definite diagnosis was made of HMD (33 infants), type II respiratory distress syndrome (16 infants) or the absence of respiratory distress (61 infants). In general, infants with HMD were more premature and had lower Apgar scores than nondistressed infants; however, there were no significant differences between the two groups in any acid-base measurement. Only in those patients of 32 to 37 weeks' gestational age was it possible to detect a significant increase in UA [H+] in infants with HMD compared to those without respiratory distress. There was evidence that the reduced Apgar score of infants with HMD may be due to immaturity and abnormal pulmonary function secondary to lung disease. It is concluded that acidosis at birth is not a factor in the development of HMD except possibly in more mature infants.

Large nuchal cystic hygromas were observed in five second-trimester aborted fetuses at autopsy. Two female fetuses with generalized edema were karyotyped as 45,X. One of these was the twin of a 46,XX normal female sibling. The association of generalized edema with large nuchal cystic hygromas was seen only in these two fetuses and represents strong phenotypic evidence of Turner's syndrome. However, the absence of hydrops was not a reliable indicator of normal karyotype. One fetus without generalized edema was karyotyped as 47,XY, +21, inv(9). The remaining cases had normal karyotypes. Placental histology was not useful in discriminating monosomy X from other conditions, but placental tissue culture was important in obtaining a cytogenetic diagnosis. Karyotyping is recommended in all cases of fetal cystic hygroma.

To assess the value of free bilirubin (FB) measurements in predicting kernicterus (KI) in sick premature infants, 91 newborns weighing less than 1,500 gm at birth were observed during the first week of like with twice daily FB and total bilirubin determinations. Autopsies were performed on 30 of the 53 infants who died. Seven had KI and 23 did not. There were no differences between infants with and with out KI in the maximum FB level (KI 18.2 +/- 4.5 [SEM] nm/liter, no KI 11.1 +/- 0.9 nm/liter, P not significant) or the total bilirubin level (KI 7.3 +/- 1.3 mg/100 ml, no KI 6.1 +/- 0.5 mg/100 ml, P not significant). In fact, three kernicteric infants had very low maximum FB levels (less than 10 nm/liter). These three infants had prolonged episodes of acidosis, hypoxemia, or hypothermia during the 24 hours preceding their maximum level of FB. Although elevated levels of FB may be predictive of KI in some infants, other factors may make the blood-brain barrier more permeable to low levels of FB. This may limit the clinical applicability of FB measurements.

To test the hypothesis that birth asphyxia has a role in the etiology of intraventricular hemorrhage (IVH), blood was collected from the umbilical artery (UA) at birth in 28 premature infants of 26 to 29 weeks gestation and analyzed for hydrogen ion concentration [H+], PCO2, standard bicarbonate level, and lactic acid level. The infants were followed up throughout their nursery stay until a diagnosis of IVH could be made or excluded, either by autopsy or clinical findings. Infants with IVH had lower Apgar scores. There were no differences in UA [H+] or bicarbonate or lactic acid levels. However, infants with IVH had a significantly higher UA PCO2. Although the difference appeared relatively small, the increase in PCO2 during labor may have been relatively large. It is concluded that hypercarbia, possibly by increasing cerebral blood flow, may be one important factor in the genesis of IVH.

Five infants with neonatal tetanus were managed with neuromuscular blockade and positive pressure ventilation. All survived. Tetanus was frequently confused with neonatal seizures at time of presentation. All infants were delivered at home. Mean age of onset of symptoms of poor suck, hypertonicity, and generalized spasms was 5.4 days with hospital admission at 6.4 days. Mean duration of mechanical ventilation was 34 days. Although hospital management of tetanus neonatorum may be expected to have a satisfactory outcome, it represents a costly and complex approach to a preventable disease.

Enzymatic peroxidase oxidation was used to study albumin-bilirubin binding in the serum of pregnant women, their term infants, and nonpregnant women. When the bilirubin titration curves were corrected for differing albumin concentrations in the three groups, the bilirubin binding of pregnant women was inferior to that of control women but better than that of their infants. Diminished maternal binding could not be explained by altered affinity. This suggests that the function of albumin during pregnancy is impaired by a factor common to both fetal and maternal circulations that appears to act by decreasing the number of available bilirubin binding sites.

To test the hypothesis that the increased incidence of hyaline membrane disease in second-born twins is related to acidosis at birth, umbilical arterial [H+] was measured in 26 sets of premature twins. Although overall Twin B had a lower Apgar score than Twin A, there was no difference in their [H+]. If the delivery interval was prolonged over 8 minutes then Twin B infants were more acidemic and had lower Apgar scores. Infants with hyaline membrane disease had lower Apgar scores, but were not more acidemic than infants without respiratory distress. Our data suggest that acidosis at birth is not an important factor in the development of hyaline membrane disease.