Response to hepatitis B vaccine in preterm infants: four-dose schedule.

The objective of this study is to test a four-dose Hepatitis B vaccine schedule in premature infants (PI) and assess the immunogenicity of the vaccine with this schedule. We studied 29 PI who received the vaccine against Hepatitis B at birth, 1, 5, and 9 months of age. Antibodies against surface antigen (Anti-HBs) were measured before the third and fourth doses and 12 weeks after the fourth dose. Levels higher than 10 mIU/mL were considered protective, whereas more than 100 mIU/mL was an excellent response. Twenty-nine PI were studied. The average weight at the time of the initial dose was 1398 g, gestational age of 32.5 weeks, and a postnatal age of 9 days. Since the initial measurement, protective levels were achieved in all patients. The response was excellent in 24.1, 75.9, and 89.7%, after the second, third, and fourth doses, respectively. No correlation was found between the type of response and the infants' weight or the postnatal age. The Anti-HBs geometrical levels were 51.9, 133, and 133 mIU/mL after the second, third, and fourth doses, respectively. The favorable results obtained might be due to: the four-dose schedule itself, the dose we used (10 microg), the time interval between the doses, and even a race factor. Our schedule seems to be useful for PI infants and probably is no longer necessary to delay the vaccination, although this should be confirmed by further studies.

The accuracy of references in paediatric journals.

We analysed the reference error rate of four paediatric journals. The overall rate was 29.7%. Individual rates were as follows: Acta Paediatr 36%, Arch Dis Child 22%, J Pediatr 29%, Pediatrics 32%; the rate of major errors was 1%, 1%, 2%, and 4%, respectively.

[Evaluation of fetal well-being using a modified Doppler flowmetric profile]. / Valoración del bienestar fetal mediante el perfil flujométrico Doppler modificado.

Decreasing perinatal morbimortality rates still represents an essential objective of antenatal care, so better diagnostic test for detecting fetal well-being are needed. The aim of this study was to compare a modified Doppler Ultrasonography Profile (DUP) with the Manning Fetal Biophysical Profile (FBP). One hundred and thirty eight high risk pregnant women between 38 and 42 gestational age, were prospectively studied with the proposed technique. The modified DUP is a quick-easy method that included five variables: umbilical Doppler velocimetry, amniotic fluid volume, fetal movements, placental grading and fetal growth pattern. The modified DUP diagnostic accuracy was compared with FBP diagnostic accuracy and a logistical regression analysis was performed to find predictors of fetal well-being. The sensitivity, specificity, and positive and negative predictive values of DUP in predicting perinatal outcome were 28%, 97%, 40% and 96.2%, respectively. On the other hand sensitivity, specificity, and positive and negative predictive values of the FBP were: 20%, 91%, 11% and 95.6%, respectively. The 95% confidence intervals for sensitivity and specificity wore 20.7-25.2 and 94.5-99.4, for the modified DUP whereas were obtained for FBP 12.2-27.7 and 85.6-96.3. The concordance between evaluated tests was 89%, with a Kappa value of 0.80. The multivariate logistical analysis showed two predictor variables as significant in the modified DUP model (umbilical Doppler velocimetry, P < 0.05, and fetal growth pattern, P < 0.05) but in the FBP no parameter reached statistical significance. Although the modified DUP had better diagnostic values an overlapping was clearly found in 95% confidence intervals, therefore it was concluded that the modified DUP proposed had similar diagnostic accuracy as FBP and could be alternatively used for assessing fetal well-being in high-risk pregnancies.

Asymmetrical septal hypertrophy in newborn infants of diabetic mothers.

The objective of this paper is to determine the frequency and outcome of asymmetrical septal hypertrophy (ASH) in large-for-gestational-age infants (LGA) born to diabetic (DM) and nondiabetic mothers (NDM), and to establish the relationship between ASH and maternal diabetes control. A comparative study was design to assess ASH in infants born to DM and NDM. The study was conducted in the Departments of Neonatology and Pediatric Cardiology of the "Hospital de Gineco-Pediatria 48", Instituto Mexicano del Seguro Social from January to December 1997. Eighty-five full-term infants of DM (group A) and 85 LGA infants of NDM (group B) were included. As a control group (group C), we studied 85 healthy, full-term infants. In all cases a Doppler echocardiogram was obtained in the first 48 h after birth, and for the ASH infants, at 2 and 4 months. Chest X ray, electrocardiogram, and laboratory tests were performed as complementary studies. ASH was present in 38.8% of LGA infants of DM and in 7.1% of NDM. The difference was significant (p < 0.01). Interventricular septum (IVS) and IVS/ posterior wall of left ventricle ratio were significantly different between groups A and B with C. There was no correlation between Hb A1 level and the presence of ASH in group A. ASH is a common finding in infants of DM. We could not find a relationship between the degree of metabolic control during pregnancy and the incidence and severity of ASH.

Assessment of therapy for arterial hypotension in critically ill preterm infants.

The aim of this paper is to assess the efficacy of albumin and dopamine compared with albumin and dobutamine in treating hypotension in preterm newborn infants (PNI). A randomized, open-label, prospective, cross-over study, was designed on 66 PNI whose weights were between 1,000 to 1,500 g, and persistent hypotension, defined as a mean arterial pressure (MAP) of < 30 mmHg. Infants were randomly allocated to two groups and received a 5% albumin infusion at a dosage of 20 mL/kg, in 30 min. Thereafter, one group received dopamine and the other dobutamine at doses of 5 microg/kg/min. If there was not an increase in MAP values > 30 mmHg, the infusions were increased every 20 min by 2.5 microg/kg/min, up to a maximum of 10 microg/kg/min. Treatment failure was considered when there was no pressure response within 2 hr after the infusion started; then patients were changed to the other catecholamine. Statistical analysis was done with student's t-test, x2, and Fisher's exact probability test. There were no differences between groups in initial features. Overall, MAP was normalized with dopamine in 29 of 33 infants and with dobutamine in 25 of 33 infants (p > 0.05). The initial dosage of 5 microg/kg/min, was adequate in 22 infants treated with dopamine and in 13 treated with dobutamine (p < 0.05). The change from dopamine to dobutamine was successful in three out of four patients, while changing from dobutamine to dopamine was adequate in seven out of eight patients. Dopamine is recognized as the drug of choice to treat hypotension in PNI. Since our results showed only small differences in responses, it is proposed that dobutamine is also as efficacious and useful as dopamine.

[Prenatal corticosteroids. Use and attitudes of the gynecology-obstetrics medical staff]. / Corticoesteroides antenatales. Empleo y actitudes del personal médico ginecoobstetra.

OBJECTIVES: 1. To evaluate the frequency of use of antenatal corticosteroids (AC) and the reasons for withholding them. 2. To estimate the knowledge and attitudes, regarding AC, from obstetricians, in a large Women and Babies Hospital. METHODS: Through a prospective, observational and transversal study we evaluated: 1. The frequency of use of AC in pregnant with preterm labor (PL) and in mothers of preterm infants (P1). When AC were not given, the reasons were recorded. 2. With an anonymous inquiry we assessed the knowledge and attitude of obstetricians regarding AC, exploring different concepts such as usefulness, frequency of use, indications, risks and contraindications. Descriptive statistics was used. RESULTS: We studied 364 patients (240 mothers of Pl and 124 pregnant women). The mean gestational age (GA) was 28.9 + 2.4 weeks. The AC were used only in 136 out of 364 (37.4%) women, and diminished to 30.9% (102/330), if are excluded 34 patients who did not receive AC because imminent delivery. Another reasons for not using AC were irregular uterine activity (18.9%), prolonged rupture of membranes without chorioamnioitis (11.4%), and GA lower than 27 weeks (11.4%) and toxemia (9.6%). Only in 43 out of 136 patients (31.6%) who were on tocolytic drugs, received AC. The schedule and doses were correct. According to the inquiry, 48/68 (0.71) of obstetricians considered AC as definitively useful, although only 22/68 (0.32) as very effective. The knowledge level was acceptable, except in signaling with precision the neonatal problems that could be prevented, as well as the lowest gestational age for use the AC. CONCLUSIONS: We considered the use of AC in our institution as suboptimal. We found that the reasons for not using them were not valid in most cases. Physician's attitudes to AC are positive but it is not reflected on their clinical practice. It is necessary a strong promotion of the usefulness of the AC for the preterm infant.

[Anion gap in perinatal asphyxia]. / Brecha aniónica en asfixia perinatal.

The aim of this study was to assess the usefulness of the anion gap (AG) for the diagnosis of Perinatal Asphyxia (PA), as well ass to evaluate the relation of AG with umbilical artery cord pH and the outcome of the newborn. We studied 62 infants in whom umbilical artery blood gases were obtained within the first 15 minutes of life. Serum sodium, chloride and potassium were simultaneously measured. AG was calculated according to the following formula: (Na + K) - (Cl + HCO3). Patients were divided in two groups depending on their pH values. Infants with a pH of 7.10 or less, were assigned to the PA group (n = 22); infants with a cord pH higher than this value, were taken as a control group. Additionally, the total group of patients was divided in survivors and non-survivors. Statistical analysis was done with mean comparation tests. Pearson's correlation index, and the sensibility, specificity and predictive values, positive and negative were calculated for a diagnosis test. Both groups were similar in gestational age, birthweight and serum electrolytes. There was significative difference in the Apgar score at one (4 vs 5.5 for PA and control group respectively) and five minutes (6 vs 7.5 respectively), as well as in the pH (6.89 +/- 0.20 vs 7.25 +/- 0.06) and the anion gap (23.4 +/- 8.1 for PA group vs 13.9 +/- 3.1 in control group). 20 mEq/L was considered as the cut-off point for AG normality. The sensibility of the test for diagnosis PA was 0.81, specificity 0.52, positive predictive value 0.48 and negative predictive value 0.84. From 37 infant newborns with a higher value than 20 mEq/L, were 11 nonsurvivors, than from 25 with a lowest measurement was 4 nonsurvivors, without statistically difference between these groups. From the total of 62 patients, were 47 survivors and 15 nonsurvivors, without difference between them in their AG, Apgar score, gestational age or serum ions. We did find statistically significant differences regarding birthweight (p < 0.05), pH (p < 0.05), and bicarbonate (p < 0.001), all these values were higher in the survivors infants. No significant correlation was found between AG and pH, however was positive correlation between AG and HCO3 (r = 0.33, p < 0.01), sodium (r = 0.22, p < 0.01) and chloride (r = 0.33, p < 0.001).

[Acute complications in full term neonates with severe neonatal asphyxia]. / Complicaciones agudas en neonatos de término con asfixia perinatal severa.

The acute systemic complications of perinatal asphyxia, defined as an umbilical artery pH at birth of 7.10 or less, were evaluated in fifty full-term newborn infants. We also investigated the prenatal complications that lead to asphyxia, and the relationship between Apgar score and cord pH. Asphyxia or fetal distress was not identified in 56% of the cases. The most common condition associated with asphyxia was prolonged labor followed by abruptio placentae. About half of the babies studied, suffered some degree of renal and brain dysfunction; 24% had severe respiratory disease. Myocardial failure was present in 24%. Regarding metabolic complications, the most frequent was hypocalcemia, present in 44%. On the other hand, there was no correlation between Apgar score and cord pH. Mortality was 22%. The main cause of death was Persistent Pulmonary Hypertension.

Independent changes in cerebrospinal fluid and in blood pH and lactate concentrations in children with purulent meningitis.

In order to evaluate the relationship of the hydrogen and lactate concentrations in cerebrospinal fluid (CSF) with those in the blood, three groups of children were studied: Group I, (n=20) with purulent meningitis (PM); Group II, (n=20) with metabolic acidosis and Group III, (n=17) with suspicion of septicemia but no metabolic acidosis. In all infants a CSF sample was obtained for cytochemical analysis, culture as well as pH and lactate determinations; the latter two were also measured in a blood sample obtained simultaneously. In group I, the CSF [H+] and [lactate] were higher than in the blood (p less than 0.001 and less than 0.01 respectively) and no significant correlation was observed between the CSF and blood values. In group II, no such differences existed in [H+] and [lactate] between both compartments and again no correlation was disclosed between CSF and blood values. In group III only the [H+] was higher in CSF than in blood (p less than 0.01) and a significant correlation was observed between both compartments (r = 0.486, p less than 0.05). The existence of differences in group I among the CSF and blood [H+] and [lactate], along with the lack of correlation between CSF and blood [H+] or [lactate], could suggest that such compartmental changes are independent from each other. However, the variations were quite large and thus, the biological significance of this observation could be questioned.

La flora intestinal aerobia en la enterocolitis necrosante. / Aerobic intestinal flora in necrotizing enterocolitis

Con el fin de evaluar si la flora intestinal aerobia de neonatos con enterocolitis necrosante (ECN) es diferente en comparacion con la de neonatos sanos se estudiaron 19 ninos con ECN y 19 testigos. Se tomaron cultivos de duodeno y recto al momento del diagnostico de ECN y tras la curacion. En los ninos testigos se obtuvieron en tiempos similares. Al momento del diagnostico los cultivos duodenales fueron positivos en 15 con ECN y seis testigos (p < 0.01). Hubo crecimiento importante (> 105 bacterias/ml aspirado) en 10 con ECN y tres testigos (p < 0.02), con predominio significativo de E. coli y Klebsiella. En la curacion no existieron diferencias entre ambos grupos. Tampoco las hubo en los cultivos rectales en el momento del diagnostico o en la curacion. Se sugiere con estos datos que la flora duodenal aerobia es diferente en ninos con ECN, y se ofrece apoyo a la importancia del hallazg