Perinatal and infant outcome of pregnant patients undergoing chronic hemodialysis.

Recently, perinatal outcome in patients undergoing chronic hemodialysis has been improved. But the conditions that will most likely result in successful pregnancy are still obscure. We retrospectively analyzed 15 pregnant patients who were undergoing chronic hemodialysis before pregnancy treated in our perinatal center. We divided these 15 cases into 2 groups: one group of 11 patients whose infants survived and the other group of 4 patients whose infants died 6 h to 8 months after birth due to prematurity. The rate of successful pregnancies having a surviving infant was 73.3% (11/15). We compared the maternal conditions and the progress of pregnancy in the 2 groups. Significant differences (p<0.01) were seen as follows. The patients in the group whose infants survived underwent hemodialysis for a shorter term before pregnancy (1-6 years), most of them (9/11) could produce urine (> or =50 ml/day), and the period of gestation was extended (33.3+/-4.7 weeks), so the infants were heavier (1,782.9+/-678.3 g). All the patients who underwent more than 9 years of hemodialysis could not have a surviving infant. From this we can assume that the shorter the period of dialysis before pregnancy, the better the condition is that is likely to result in women giving birth and the better is their infant's chance of survival.

Neonatal hypoglycemia in infants with intrauterine growth retardation due to pregnancy-induced hypertension.

The early-onset type (onset earlier than 28 gestational weeks) of pregnancy induced hypertension (PIH) has the clinical characteristics of a high incidence of intrauterine growth retardations (IUGR), fetal distress, neonatal hypoglycemia and hypertensive disposition. Moreover, the infants from early-onset type of PIH mothers showed a statistically significant higher incidence of neurological handicap (cerebral palsy, mental retardation and epilepsy) than late onset type. The infants with a neurological handicap had severe IUGR and intractable hypoglycemia in the early neonatal period, probably due to low storage of glucose in the liver and fetal hypoxia. Appropriate perinatal management, including proper evaluation of fetal well-being and good timing of delivery, could improve the outcome of infants from early-onset type of PIH mothers.

Follow-up study of neonatal hypoglycemia.

A follow-up study was done on the neurological handicap and intellectual development of high-risk infants with neonatal hypoglycemia. The frequency of neonatal hypoglycemia in high-risk infants is 8.6%, and the incidence of a major neurological handicap in high-risk infants with neonatal hypoglycemia is 11%. Risk factors for the handicap group are very low birthweight, intrauterine growth retardation, perinatal asphyxia and mothers with pregnancy-induced hypertension. Average DQ at 1.5 and 2.5 years and IQ at 4 and 6 years of very low birthweight infants with neonatal hypoglycemia showed no significant difference, in contrast to the control group.

Application of nasal continuous positive airway pressure to early extubation in very low birthweight infants.

Using a preset protocol for early extubation, 50 babies were randomly selected to post-extubation headbox or post-extubation nasal continuous positive airway pressure (N-CPAP). All infants weighed less than 1500 g, had a gestational age of less than 34 weeks, and had been weaning from mechanical ventilation within seven days of life. The criteria for extubation included stable condition, fraction of inspired oxygen (FIO2) of < or = 35%, peak inspiratory pressure (PIP) of < or = 15 cm H2O (1.47 kPa), and ventilator rate of 6/minute. Before extubation, a loading dose of aminophylline was given followed by maintenance treatment. If reintubation was not required within 72 hours of the initial extubation the procedure was considered successful. The reintubation criteria included FIO2 > or = 70% to maintain arterial oxygen tension (PaO2) of > or = 50 mm Hg (6.67 kPa) or pulse oximetry between 90-96% and pH of < 7.25, and arterial carbon dioxide tension (PACO2) of > 60 mm Hg (8.00 kPa) and severe or recurring apnoea. The overall success rate of early extubation was 66% (33/50). The individual successful extubation rate of post-extubation in the N-CPAP group and the post-extubation headbox group were 84% (21/25) and 48% (12/25), respectively (p = 0.017; chi 2). There were no significant differences in clinical characteristics between the two groups. The most common cause of failure in early extubation was apnoea, and most occurred in the headbox group (9/12). These results suggest that application of N-CPAP to a preset protocol for extubation can achieve a better success rate of early extubation in very low birthweight (VLBW) infants.

A multicenter randomized trial of high frequency oscillatory ventilation as compared with conventional mechanical ventilation in preterm infants with respiratory failure.

A multicenter randomised trial was conducted in nine neonatal centers in Japan to re-evaluate the safety and the efficacy of high frequency oscillatory ventilation using the piston type oscillator (Hummingbird) in the treatment of respiratory failure in preterm infants weighing between 750 and 2000 g at birth. A total of 92 infants were enrolled in the study. Forty-six infants were allocated to high frequency oscillatory ventilation and 46 infants to conventional mechanical ventilation. There were no differences in sex, birth weight, gestation and Apgar score between groups. The study was begun 2.0 +/- 1.6 h (mean +/- S.D.) after birth in the high frequency oscillation group and 1.7 +/- 1.5 h after birth in the conventional mechanical ventilation group. The absence of intraventricular hemorrhage was confirmed by echography in all cases before beginning ventilation. Mortality was similar in high frequency oscillatory ventilation and conventional mechanical ventilation (0 and 2%). The incidence of intraventricular hemorrhage was also similar in the high frequency and conventional mechanical ventilation groups (15 and 13% overall; 4 and 2% in grades III and IV, respectively). Nine percent of the infants in high frequency oscillatory ventilation and 13% in conventional mechanical ventilation developed bronchopulmonary dysplasia, but the difference was not significant. The frequency of air leaks was also equal in both groups. Periventricular leukomalacia was detected in 9% of infants on conventional mechanical ventilation and 2% on high frequency oscillation, but the difference was not significant. Mean airway pressure was significantly higher in the high frequency oscillatory ventilation group and the infants on high frequency oscillation showed a significantly higher arterial to alveolar oxygen tension ratio after 6 h of treatment. These results suggest that high frequency oscillatory ventilation does not increase the risk of severe complications such as air leaks, intraventricular hemorrhage or periventricular leukomalacia when it is used by experienced neonatologists. Indeed high frequency oscillatory ventilation helps provide better oxygenation with higher mean airway pressure without increasing the risk of bronchopulmonary dysplasia and severe complications such as air leaks and intraventricular hemorrhage.

Prevention of perinatal transmission of hepatitis B virus carrier state.

By means of passive and active immunization with hepatitis B immunoglobulin and hepatitis B vaccine, 396 of 407 babies born to hepatitis B antigen-positive carrier mothers, were protected from establishing the hepatitis B virus (HBV) carrier state during a follow-up period of 12 months or longer. Four infants developed the HBV carrier state before the completion of the immunoprophylaxis schedule, and another seven developed the state after the completion of the schedule. Seroconversion of anti-HBc was observed in 26.8% of the successfully protected infants. In Japan a nationwide program to prevent the vertical transmission of HBV with these procedures was established in 1986, and so liver diseases due to HBV are expected to be eliminated in the near future.

Prader-Willi syndrome with del(15)(q11,q13) associated with hepatoblastoma.

A case of Prader-Willi syndrome who later developed hepatoblastoma is reported. Prader-Willi syndrome was suspected because of hypotonia, hypopigmentation, and undescended testes when he was a newborn infant. The diagnosis was confirmed by chromosome analysis, which showed 46XY del(15)(q11, q13). When he was 1 year 4 months old, a liver tumor and high serum AFP were found. At operation a large tumor arising from the caudate lobe was found and the tumor was totally resected. After completion of the hepatectomy, he developed circulatory collapse of unknown cause and died shortly after the operation. Histopathologic examination revealed that the tumor was composed of two components, well differentiated cells and poorly differentiated cells. The well differentiated part did not dominate the poorly differentiated part, so it was diagnosed as poorly differentiated hepatoblastoma. This is the first reported case of Prader-Willi syndrome with a pediatric malignant tumor.

Trace elements in human transitory milk. Variation caused by biological attributes of mother and infant.

Multielement analysis was performed on human milk collected on 5-9-d postpartum from 51 Japanese females using inductively coupled plasma (ICP) mass spectrometry (MS), ICP atomic emission spectrometry (ICP-AES) and fluorometry. Thirty-one elements were detected by these analytical methods in milk. Twelve elements (Na, Mg, P, S, K, Ca, Cu, Zn, Se, Sr, Rb, and Mo) were detected in all of the samples. Al, Cs, and Ba were the elements detected by ICP-MS in more than half of the samples. Multiple regression analysis extracted biological attributes of mother and infant, such as maternal stature, maternal wt, or infant's birth wt, as statistically significant factors contributing to the variation in elemental concentration in milk. However, the rates of contribution were small in all cases. It was concluded that the biological attributes of mother and infant examined in this study were not the major factors that contribute to elemental variation in human milk.

Combined passive and active immunization for preventing perinatal transmission of hepatitis B virus carrier state.

Prevention of perinatal transmission of hepatitis B virus carrier state in neonates at high risk was attempted by a combined passive and active immunization. Immediately after delivery, ten babies born to mothers who were asymptomatic carriers of hepatitis B surface antigen (HBsAg) and seropositive for hepatitis B e antigen received an intravenous injection of F(ab')2 fragments (200 IU) derived from hepatitis B immune globulin (HBIG). On the following day, none of them revealed detectable levels of the antibody to HBsAg in their sera, and received an intramuscular injection of HBIG (200 IU) which was repeated at 2 and 4 months of age. Vaccination with 40 micrograms of purified, formalin-inactivated HBsAg particles was given to the nine babies at three months and repeated at 4, 5, and 7 months after birth. All of them maintained detectable levels of the antibody and escaped infection throughout the first 12 months of their lives. The one baby who did not have detectable F(ab')2 in serum for 24 hours developed persistent HBs antigenemia which was noticed as early as seven days after birth.