Proactive management of extreme prematurity: disagreement between obstetricians and neonatologists

OBJECTIVE

To verify, in extremely preterm infants, if disagreement between obstetricians and neonatologists regarding proactive management is associated with early death.

STUDY DESIGN

Prospective cohort of 484 infants with 23(0/7) to 26(6/7) weeks, without malformations, born from January 2006 to December 2009 in eight Brazilian hospitals. Pro-active management was defined as indication of ≥1 dose of antenatal steroid or cesarean section (obstetrician) and resuscitation at birth according to the international guidelines (neonatologist). Main outcome was neonatal death in the first 24  h of life.

RESULT

Obstetricians and neonatologists disagreed in 115 (24%) patients: only neonatologists were proactive in 107 of them. Disagreement between professionals increased 2.39 times the chance of death in the first day (95% confidence interval 1.40 to 4.09), adjusted for center and maternal/neonatal clinical conditions.

CONCLUSION

In infants with 23 to 26 weeks of gestation, disagreement between obstetricians and neonatologists, translated as lack of antenatal steroids and/or vaginal delivery, despite resuscitation procedures, increases the odds of death in the first day.

Cerebellar growth in very low birth weight infants

OBJECTIVE

The aim of this study was to assess cerebellar growth of very low birth weight infants from birth to discharge and compare it with term infants.

STUDY DESIGN

Very low birth weight infants were matched by gender, adequacy of weight to gestational age at birth and postmenstrual ages at hospital discharge to term newborns. Exclusion criteria were central nervous system malformation, peri-intraventricular hemorrhage, cerebellar hemorrhage and meningitis. Transverse cerebellar diameter was measured by cranial ultrasound at birth and at hospital discharge in cases, and at birth in matched controls. Very low birth weight infants had magnetic resonance imaging done in the first year.

RESULT

Cerebellar growth was similar in very low birth weight infants without periventricular leukomalacia and controls, and smaller in cases with periventricular leukomalacia than in controls.

CONCLUSION

We suggest that cerebellar growth is normal in the absence of supratentorial injury.

Score for Neonatal Acute Physiology and Perinatal Extension II as a predictor of retinopathy of prematurity: study in 304 very-low-birth-weight preterm infants

AIM

To evaluate the use of the Score for Neonatal Acute Physiology and Perinatal Extension (SNAPPE-II) at admission to predict the development of retinopathy of prematurity (ROP) among very-low-birth-weight preterm babies.

METHODS

A prospective cohort study included 304 infants screened for ROP from July 2004 to October 2007. The main outcomes were the development of any stage ROP and severe ROP. The main variable was the SNAPPE-II obtained at admission. Seventeen risk factors for ROP were studied by univariate analysis (chi(2) and Student's t test). A simple descriptive analysis was used for the SNAPPE-II (mean, median, standard deviation and interquartile range: p25-p75). Logistic regression and receiver-operating characteristic (ROC) curve were calculated for SNAPPE-II. Ophthalmological examinations started at the 6th week of life and were repeated until the 45th week of corrected gestational age (GA).

RESULTS

The mean GA and mean birth weight of the whole cohort were 30.3 weeks (+/-2.2) and 1,209.2 g (+/-277.7), respectively. The median SNAPPE-II among non-ROP and ROP patients were 6.0 and 15.0, respectively (p = 0.001). When compared with severe ROP patients (25.0) there was also a significant difference (p = 0.003). After logistic regression, the SNAPPE-II adjusted odds ratio for ROP was 1.024. The area under the ROC curve was 0.62 (95% confidence interval: 0.55-0.70, p < 0.001). The best discriminative cutoff value was 8.5 (sensitivity: 68%; specificity: 54%; positive predictive value: 37.3%; negative predictive value: 80.6%).

CONCLUSIONS

The SNAPPE-II values at admission were significantly higher among babies with ROP, suggesting a positive association between higher scores with the development of ROP, but after adjusted logistic regression and ROC curve results, the SNAPPE-II scores at admission did not enhance the assessment of risk for ROP.

Cortisol and 17-alpha-hydroxy-progesterone levels in infants with refractory hypotension born at 30 weeks of gestation or less

Refractory hypotension is frequent in very low-birth weight infants, whose hypothalamic-pituitary-adrenal axis has been suggested to be immature. The objective of the present study was to evaluate basal cortisol and 17-alpha-OH-progesterone in the first 36 h of life in preterm infants with and without refractory hypotension (mean arterial blood pressure below the lower limit for gestational age throughout the study despite aggressive volume expansion and use of vasopressors). Thirty-five infants with <or=30 weeks of gestation and a birth weight <or=1250 g, with no postnatal use of corticosteroid or death in the first 48 h were studied. Mean arterial pressure was measured every 4 h during the first 48 h. Cortisol and 17-alpha-OH-progesterone were determined at 12 and 36 h and patients were divided into refractory hypotensive (N = 15) and control (N = 20) groups. The groups were not different regarding type of delivery, use of prenatal corticosteroid, requirement of mechanical ventilation, use of vasopressor drugs, morphine, fentanyl, prophylactic indomethacin, and mean sample timing. Although refractory hypotensive newborns were more immature, were smaller, suffered more deaths after 48 h of life and had a higher SNAPPE-2 score, their cortisol and 17-alpha-OH-progesterone levels were not different from controls at 12 h and at 36 h. The increase of cortisol in newborns with refractory hypotension 36 h after birth was significantly higher than in controls. Despite the fact that refractory hypotensive very low-birth weight neonates were submitted to a very stressful condition, their cortisol and 17-alpha-OH-progesterone levels were similar to controls.

Incidence and risk factors for retinopathy of prematurity in very low and in extremely low birth weight infants in a unit-based approach in southern Brazil

AIMS

To analyse the incidence and risk factors for retinopathy of prematurity (ROP) and survival rates among extremely low birth weight (ELBW) and very low birth weight (VLBW) preterm infants.

METHODS

A prospective cohort study of 352 infants admitted at a teaching hospital, Hospital de Clinicas de Porto Alegre, Brazil, between October 2002 and December 2006, was screened for ROP. The ELBW group comprised infants whose birth weight (BW) was < or = 1000 g and the VLBW group comprised those infants whose BW were > 1000 g and < or = 1500 g. Perinatal risk factors for ROP were assessed using univariate and multivariate analysis.

RESULTS

Of the 352 neonates screened, 88 were ELBW babies. Survival rates among ELBW and VLBW were 47.8 and 88.7%, respectively. ROP affected 48.9% of ELBW infants and 18.2% of VLBW babies. Threshold disease occurred in 21 patients, 15 of whom were born weighing < 1000 g. Only 2.3% of the neonates born with more than 1000 g developed treatable disease. Univariate analysis showed that gestational age (GA), BW, use of indomethacin and erythropoietin, blood transfusions, and intraventricular haemorrhage were associated with ROP. After logistic regression, the most important adjusted risk factors were BW (OR: 1.002;95% CI: 1.001-1.003; P=0.003), GA (OR: 1.254;95% CI: 1.082-1.455; P=0.003), and use of erythropoietin (OR: 2.486;95% CI: 1.182-5.231; P=0.016).

CONCLUSION

This study showed reduced survival rates, high incidence of ROP, and a greater need of treatment among ELBW infants as compared to VLBW babies admitted in this institution.

Umbilical cord blood and neonatal endothelin-1 levels in preterm newborns with and without respiratory distress syndrome

Increased pulmonary vascular resistance in preterm newborn infants with respiratory distress syndrome is suggested, and endothelin-1 plays an important role in pulmonary vascular reactivity in newborns. We determined umbilical cord blood and neonatal (second sample) levels of endothelin-1 in 18 preterm newborns with respiratory distress syndrome who had no clinical or echocardiographic diagnosis of pulmonary hypertension and 22 without respiratory distress syndrome (gestational ages: 31.4 +/- 1.6 and 29.3 +/- 2.3 weeks, respectively). Umbilical cord blood and a second blood sample taken 18 to 40 h after birth were used for endothelin-1 determination by enzyme immunoassay. Median umbilical cord blood endothelin-1 levels were similar in both groups (control: 10.9 and respiratory distress syndrome: 11.4 pg/mL) and were significantly higher than in the second sample (control: 1.7 pg/mL and respiratory distress syndrome: 3.5 pg/mL, P < 0.001 for both groups). Median endothelin-1 levels in the second sample were significantly higher in children with respiratory distress syndrome than in control infants (P < 0.001). There were significant positive correlations between second sample endothelin-1 and Score for Neonatal Acute Physiology and Perinatal Extension II (r = 0.36, P = 0.02), and duration of mechanical ventilation (r = 0.64, P = 0.02). A slower decline of endothelin-1 from birth to 40 h of life was observed in newborns with respiratory distress syndrome when compared to controls. A significant correlation between neonatal endothelin-1 levels and some illness-severity signs suggests that endothelin-1 plays a role in the natural course of respiratory distress syndrome in preterm newborns.

Effect of perinatal asphyxia on thyroid-stimulating hormone and thyroid hormone levels

AIM

To compare serum concentrations of thyroid hormones--T4, T3, free T4 (FT4) and reverse T3 (rT3)--and thyroid-stimulating hormone (TSH) found in the umbilical cord blood of term newborns with and without asphyxia and those found in their arterial blood collected between 18 and 24 h after birth. A further aim of the study was to assess the association between severity of hypoxic-ischemic encephalopathy and altered thyroid hormone and TSH levels, and between mortality and FT4 levels in the arterial blood of newborns between 18 and 24 h of life.

METHODS

A case-control study was carried out. The case group comprised 17 term newborns (Apgar score < or = 3 and < or = 5 at the first and fifth minutes; umbilical cord blood pH < or = 7.15) who required bag and mask ventilation for at least one minute immediately after birth. The control group consisted of 17 normal, term newborns (Apgar score > or = 8 and > or = 9 at the first and fifth minutes; umbilical cord blood pH > or = 7.2). Cord blood and arterial blood samples were collected immediately after birth and 18 to 24 h after birth, respectively, and were used in the blood gas analysis and to determine serum concentrations of T4, T3, FT4, rT3 and TSH by radioimmunoassay. All newborns were followed-up until hospital discharge or death.

RESULTS

Gestational age, birthweight, sex, size for gestational age, mode of delivery and skin color (white and non-white) were similar for both groups. No differences were found in mean levels of cord blood TSH, T4, T3 and FT4 between the groups. In the samples collected 18 to 24 h after birth, mean levels of TSH, T4, T3 and FT4 were significantly lower in the asphyxiated group than in the control group. Mean concentrations of arterial TSH, T4 and T3 between 18 and 24 h of life were lower than concentrations found in the cord blood analysis in asphyxiated newborns, but not in controls. In addition, asphyxiated newborns with moderate/severe hypoxic-ischemic encephalopathy presented significantly lower mean levels of TSH, T4, T3 and FT4 than those of controls. None of the asphyxiated newborns with FT4 > or = 2.0 ng/dl died; 6 out of the 11 asphyxiated newborns with FT4 < 2.0 ng/dl died.

CONCLUSIONS

Serum concentrations of TSH, T4, T3 and FT4 are lower in asphyxiated newborns than in normal newborns between 18 and 24 h of life; this suggests central hypothyroidism secondary to asphyxia. Asphyxiated newborns with moderate/severe hypoxic-ischemic encephalopathy present a greater involvement of the thyroid function and consequently a greater risk of death.

[Predictive value of SNAP and SNAP-PE for neonatal mortality]

OBJECTIVE: To evaluate the Score for Neonatal Acute Physiology and the Score for Neonatal Acute Physiology Perinatal Extension as neonatal mortality predictors in our neonatal intensive care unit, and to compare their results. METHODS: All newborn infants admitted to our neonatal intensive care unit from March 1997 through December 1998 were prospectively evaluated just at completion of 24 hours of life for SNAP and SNAP-PE. Exclusion criteria were: death or discharge from the neonatal intensive care unit in the first 24 hours of life, congenital malformations incompatible with life, and outborn infants. RESULTS: 553 newborn infants were included in the study and 54 died. The median SNAP and SNAP-PE values were higher in those who died. Infants were allocated to five different raising ranges of SNAP and SNAP-PE severity. SNAP: up to 6, 7-11, 12-15, 16-24, higher than 24 (mortality: 3%, 11%, 29%, 48%,75%, respectively). SNAP-PE: up to 11, 12-23, 24-32, 33-50, higher than 50 (mortality: 3%, 10%, 53%, 78%, 83%, respectively). The optimal cut off points based on ROC curve were 12 for SNAP, and 24 for SNAP-PE. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for death were figured out. SNAP 12: sensitivity 79.6%, specificity 71.7%, PPV 23.4%, NPV 97%. SNAP-PE 24: sensitivity 79.6%, specificity 80%, PPV 30%, NPV 97.3%. The area under the curve (Az) were 81.4% for SNAP, and 85.1% for SNAP-PE, both statistically significant. There were no statistical differences between the two areas under the curve. CONCLUSIONS: SNAP and SNAP-PE are excellent predictors of neonatal survival. Therefore, we recommend their use in Neonatal Intensive Care Units.

[Do newborn infants feel pain when submitted to gastric suctioning?]

OBJECTIVES: Evaluate physiological and behavioral parameters to verify if newborns feel pain when submitted to gastric suctioning. METHODS: 50 healthy newborns over 33 weeks gestational age, weighing more than 1999g, were submitted to gastric suctioning, randomly selected, and divided into two groups: Friction/Lancing and Lancing/Friction. The newborns were assessed through the Neonatal Infant Pain Scale (NIPS) (0-7, pain>3) by two independent observers in three different moments: one minute before, during, and one minute after gastric suctioning, heel lancing and foot friction, with simultaneous monitoring of heart rate, respiratory frequency, and hemoglobin oxygen saturation. RESULTS: The respiratory frequency only decreased during gastric suctioning (P=0.004). The heart rate was lower during gastric suctioning (P<0.0001), during the heel lacing procedure in the Friction/Lancing group (P=0.01), and during friction in the Friction/Lancing group (P=0.022). The hemoglobin oxygen saturation suffered no alterations during the three procedures. The results obtained through NIPS revealed that both groups felt pain during gastric suctioning and heel lancing, and did not feel pain during friction (P<0.0001). CONCLUSION: During the gastric suctioning procedure, newborns responded as if it were a painful stimulus. Physiological alterations were neither specific nor sensitive to pain assessment in newborn infants.

[Hypoxic-ischemic syndrome]

OBJECTIVE: To review the literature on the hypoxic-ischemic syndrome, emphasizing its physiopathology, clinical manifestations, and treatment. SOURCES: Electronic search in the Medline and LILACS databases, with selection of the most relevant articles. SUMMARY OF THE FINDINGS: The hypoxic-ischemic syndrome is a multisystem disease with generalized manifestations. The physiopathology is based on hypoxic-ischemic brain injury and reperfusion with cellular injury caused by failure of ATP production secondary to ischemia, and overproduction of oxidative substances caused by reperfusion. Neurological, cardiovascular, respiratory, metabolic, gastrointestinal, renal, and hematological manifestations are frequent. Multisystem clinical management is complex; the neuroprotective approach is still experimental; and the prognosis is not good for those patients with severe hypoxic-ischemic encephalopathy. CONCLUSIONS: The management of the hypoxic-ischemic syndrome is a great challenge to pediatricians., since treatment requires multisystem intervention.

[Effect of perinatal asphyxia on thyroid hormones]

OBJECTIVE: To verify the effect of perinatal asphyxia on thyroid hormone levels in term newborn infants. METHODS: We carried out a case-control study with 17 term and asphyxiated (A) and 17 term and control (N) newborn infants at the Hospital de Clínicas de Porto Alegre. Patients were paired according to color of skin, sex, type of delivery, gestational age, and weight at birth. We collected umbilical cord plasma T4, T3, free T4, reverse T3, and TSH after 18 to 24 hours of life and from asphyxiated and control newborn infants. RESULTS: There were no differences in thyroid hormones of cord blood, with the exception of reverse T3, which was higher in A than in controls [median (25th-75th percentile): A= 2(1.4-2); N= 1.41 (1.13-1.92); P=0.037)]. Thyroid hormone levels were lower in A than in controls on samples collected within 18-24 hours after birth, except for reverse T3, which was similar in both groups [average -/+ SD: T4 A= 9.79 -/+ 2.59; N=14.68 -/+ 3.05; P<0.001; median T3 A= 40.83 (37.4-80.4); N= 164 (56.96-222.5); P=0.003; average -/+ SD: free T4 A=1.85 -/+ 0.92; N= 2.8 -/+ 0.74; P=0.004; median: reverse T3 A=1.54 (1.16-1.91); N=1.31(0.87-2); P=0.507; TSH A=9.1 (6.34-12.95); N=14.5(12.9-17.85); P=0.008]. CONCLUSIONS: Our data suggest that lower T4, free T4, and T3 levels are secondary to lower TSH levels in asphyxiated newborns; also, peripheral metabolism of T4 in asphyxiated infants can be altered due to low T3 and normal reverse T3 levels.

[The effect of recombinant human erythropoietin on the treatment of anemia of prematurity]

OBJECTIVE: To assess the efficacy of erythropoietin in the prevention and treatment of anemia of prematurity, correlating the use of this drug with weight gain, length, and head circumference and comparing two administration schemes of he same weekly dose: daily use and twice a week. METHODS: The study comprised 42 premature newborns with gestational age up to 33 weeks, birthweight up to 1550 g, and postnatal age between 10 and 35 days. The newborns were randomized into three groups: patients in group 1 received seven daily doses of 100 U/kg erythropoietin per week; patients in group 2 received two 350 U/kg erythropoietin doses per week; and patients in group 3 did not receive the drug. Hematologic measurements, blood transfusion requirements, and growth rates were followed during therapy. RESULTS: Cases and controls did not differ with respect to weight, length, head circumference, and total time of hospital stay. At the end of the study, no significant difference was observed in the platelet count measurement means, white blood cell count, and ferritin levels in the three groups. However, the final hematocrit and hemoglobin values of patients who did not receive erythropoietin were significantly lower than those of patients who received the drug. The absolute reticulocyte count mean was significantly higher in patients who received erythropoietin after two weeks of treatment when compared with those patients who did not receive the drug. Patients in group 1 e 2 received fewer excessive transfusions (2 or more) than patients in group 3. The administration of 700 U/kg/week erythropoietin significantly reduced the number of excessive blood transfusions. There is no significant difference in blood transfusion volume between patients who received erythropoietin on a daily basis and those who received the drug twice weekly. CONCLUSIONS: the use of erythropoietin did not influence weight gain and growth. The administration of 700 U/kg/week erythropoietin in premature infants with gestational age up to 33 weeks and birthweight up to 1550 g stimulates erythropoiesis and significantly reduces excessive blood transfusion requirements. Erythropoietin showed to be a safe and well tolerated medication, with no short-term side effects in the study population.

A randomized, double-masked, placebo-controlled trial of recombinant granulocyte colony-stimulating factor administration to preterm infants with the clinical diagnosis of early-onset sepsis

OBJECTIVE

We performed a randomized, double-masked, parallel-groups, placebo-controlled trial of recombinant granulocyte colony-stimulating factor (rG-CSF) administration to 44 preterm neonates who had blood cultures obtained and antibiotics begun because of the clinical diagnosis of early-onset sepsis. Two primary outcome variables were tested 1) mortality and 2) development of nosocomial infections over the 2-week period after dosing.

DESIGN AND METHODS

The treatment group (n = 22) received 10 microgram/kg/day of intravenous rG-CSF once daily for 3 days and the placebo group (n = 22) received the same volume of a visually indistinguishable vehicle. Mortality and culture-proven nosocomial infections were recorded. Immediately before the first, second, and third doses, and again 10 days after the first dose, serum concentrations were determined for tumor necrosis factor-alpha, interleukin 6, granulocyte-macrophage colony stimulating factor, and G-CSF, and blood leukocyte counts, absolute neutrophil counts, immature/total neutrophil ratios, platelet counts, and hemoglobin concentrations were measured.

RESULTS

The treatment and placebo groups were of similar gestational age (29 +/- 3 vs 31 +/- 3 weeks) and birth weight (1376 +/- 491 vs 1404 +/- 508 g), and had similar Apgar scores and 24-hour Score for Neonatal Acute Physiology scores. The mortality rate was not different between treatment and placebo groups. However, the occurrence of a subsequent nosocomial infection was lower in the rG-CSF recipients (relative risk:.19; 95% confidence interval:.05-.78). rG-CSF treatment did not alter the serum concentrations of the cytokines measured (except for G-CSF). Serum G-CSF levels and blood neutrophil counts were higher in the treatment than in the placebo group 24 hours and 48 hours after dosing.

CONCLUSIONS

Administration of 3 daily doses of rG-CSF (10 microgram/kg/day) to premature neonates with the clinical diagnosis of early-onset sepsis did not improve mortality but was associated with acquiring fewer nosocomial infections over the subsequent 2 weeks.

[Assessing the efficacy of the recombinant human granulocyte colony-stimulating factor "rhG-CSF" in the treatment of early neonatal sepsis in premature neonates]

OBJECTIVE: To evaluate the efficacy of the recombinant human granulocyte colony-stimulating factor (rhG-CSF) in the treatment of early-onset neonatal sepsis among premature infants.MATERIALS AND METHODS: A double-blind, randomized, placebo-controlled trial was performed among forty-four preterm neonates who had "clinical diagnosis" of early-onset sepsis. The treatment group (n=22) received 10 micro g/kg/d of rhG-CSF, IV once daily for three consecutive days, and the placebo group (n=22) received the same volume of a visually-indistinguishable vehicle. Prior to the first dose, and prior to the second and third doses, and again 10 days after the first dose, we measured tumor necrosis factor-a, interleukin-6, granulocyte-macrophagocyte colony-stimulating factor, G-CSF, leukocyte count, absolute neutrophil count, immature/total neutrophil ratio, platelet count, and hemoglobin concentration. A bone marrow aspiration was performed seven days after the first dose, and both the neutrophil storage pool (NSP) percent and the NSP/NPP (neutrophil proliferative pool) ratios were tabulated.RESULTS: The treatment and placebo groups were of similar gestational age (29-/+ 3 vs 31-/+ 3 weeks) and birth weight (1376 -/+ 491 vs 1404 -/+ 508 grams). They had similar Apgar scores and 24 hour SNAP scores. No deaths occurred during the first week of life among the treatment group while three deaths occurred in the placebo group. RhG-CSF treatment did not alter the serum concentrations of the cytokines measured (except for G-CSF). Serum G-CSF levels, blood leukocyte counts, absolute neutrophil counts, NSP percentages, and NSP/NPP ratios were higher in the treatment group 24 hours and 72 hours after dosing. The occurrence of a subsequent infection over the two week period following dosing was significantly lower in the treatment group (n=2) than in the placebo group (n=9; p<0.02, RR 0.19 [0.05-0.78]). The overall mortality rate during the entire hospitalization was not different between treatment and placebo groups.CONCLUSIONS: Administration of rhG-CSF to premature neonates with the clinical diagnosis of early-onset sepsis was associated with lower incidence of nosocomial infection over the ensuing three weeks period, but it did not change the overall mortality rate.

[Neonatal sepsis: diagnosis and treatment]

OBJECTIVE: Review the literature on diagnosis and treatment of neonatal sepsis. METHODS: The most important articles on neonatal sepsis were selected through MEDLINE. RESULTS: The present review analyzes the different methods of diagnosis, laboratory and clinical, as well as the different therapeutic managements of neonatal sepsis. CONCLUSION: Neonatal sepsis is a severe disease that must be diagnosed early and properly treated in order to avoid lethal outcome.

Evaluation of interleukin-6, tumour necrosis factor-alpha and interleukin-1beta for early diagnosis of neonatal sepsis

The objective of this study was to assess the contribution of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) to an early diagnosis of early-onset neonatal sepsis. A cohort of 117 newborn infants delivered during a 1-y period had IL-6, TNF-alpha and IL-1beta, blood and cerebrospinal fluid (CSF) cultures, leucocyte and platelet count collected on the initial evaluation of possible early-onset sepsis. They were divided into four groups: I, positive blood and/or CSF cultures; II, probably infected with clinical sepsis but negative cultures; III, same as group II but mother received antibiotic antepartum; and IV, newborn infants that did not receive any antibiotic therapy. There were no differences among the four groups with respect to mean gestational ages and birthweights, median Apgar scores, type of delivery, or number of newborn infants with leucocyte count <5000 mm(-3) or >25000 mm(-3), platelet count <100000 mm(-3), immature/total neutrophil ratio >0.2, absolute neutrophil count <1000mm(-3) and median IL-1beta levels. Median IL-6 and TNF-alpha levels were significantly higher in groups with patients with a diagnosis of clinical sepsis than in controls. The optimal cut-off point was 32 pg ml(-1) for IL-6 and 12 pg ml(-1) for TNF-alpha. The combination of both provided a sensitivity of 98.5%. In conclusion, the combination of IL-6 and TNF-alpha is a highly sensitive marker of sepsis in the immediate postnatal period.

[Clinical manifestations in term newborn infants with different degrees of acidemia in umbilical cord blood]

OBJECTIVE: To verify if Apgar score plus umbilical cord pH are adequate to predict which newborn infant will develop multiorgan system disfunction. METHODS: A study including all term newborn infants with Apgar scores in the first and fifth minutes of life < 7 and umbilical cord blood pH < 7.20 born in Hospital de Clínicas de Porto Alegre from March 1995 through March 1998 was performed. Venous umbilical cord blood was collected for blood gas analysis. Newborn infants were divided in two groups: Group A with pH < 7.0, and Group B with pH >/= 7.0 and < 7.20. Patients were evaluated for the presence of pulmonary hypertension, renal failure, inappropriate secretion of antidiuretic hormone, ischemic cardiopathy, early seizures, neurologic injury at hospital discharge and death. RESULTS: Twenty five newborn infants were included in the study.Twelve formed Group A, and 13, Group B. There were no differences between both groups in respect to mode of delivery, gender, color and birth weight. Group B had a lower gestational age than Group A. There were significant differences between both groups in mean cord blood pH, pCO(2) and BE (p<0.05). There was a positive association between umbilical cord blood pH and Apgar score. Higher occurrence of neurologic injury at hospital discharge in Group A was the only statistically significant clinical manifestation (p<0.05). CONCLUSION: Apgar score and umbilical cord pH are not adequate criteria to predict multiorgan system dysfunction.

[Plasmatic levels of interleukin-1beta and interleukin-6 in newborn infants with fever]

OBJECTIVE: To study plasma levels of IL-1beta and IL-6 in order to distinguish the presence of bacterial infection in newborn infants with fever. METHODS: A cohort of 117 newborn infants with postnatal age equal to or less than 5 days, with no previous use of antibiotic therapy, and with clinical suspicion of bacterial infection was studied from July 1995 through August 1996. Those with definite criteria for sepsis were considered infected. Fever was defined as axillar temperature > 37.5 degrees C in three independent measurements. The patients were classified in four different groups: Group 1: infected with fever; Group 2: infected without fever; Group 3: not infected with fever; Group 4: not infected without fever. Complete blood count, platelet count, blood or other fluid cultures, and plasmatic levels of IL-1beta and IL-6 were collected before the beginning of antibiotic therapy. RESULTS: Of the 117 newborn infants studied were 66 infected and 51 not infected. Fever was present in 45 (38.46%). The median values of IL-1beta and IL-6 were significantly higher in newborn infants with fever than in those with no fever. There were significant differences between groups 1 and 2, 1 and 4, and 2 and 3 for IL-1beta. There were no significant differences between groups 2 and 4, and 1 and 3 for IL-1beta. Eight (72%) newborn infants with no infection and no fever had environment heating, and 3 had dehydration. There were no differences in median IL-6 levels between groups 1 and 2, and 3 and 4. There were significant differences in the median IL-6 levels between groups 1 and 3, and 1 and 4. CONCLUSIONS: IL- 6 is a marker of early neonatal sepsis. IL-1beta is related to neonatal fever response independently of the presence of bacterial infection.

[Bronchopulmonary dysplasia]

OBJECTIVE: To review the literature on bronchopulmonary dysplasia. METHODS: The most important articles on bronchopulmonary dysplasia were selected through MEDLINE. RESULTS: The present review analyzes the different concepts, pathogenesis, clinical presentation, treatment and prophylaxis of bronchopulmonary dysplasia. CONCLUSIONS: bronchopulmonary dysplasia is a frequent condition of very low birth weight infants with hyaline membrane disease who require mechanical ventilation. The pathogenic factors are prematurity, oxygen therapy, mechanical ventilation, pulmonary edema, and infection. Treatment is based on good oxygenation, fluid restriction, nutritional support, diuretics, betamimetic drugs, xanthines, and steroids. Prophylaxis includes avoiding prematurity and using pre-natal steroids, superoxide dismutase, and post-natal steroids.

Transient elevation of aldosterone levels in perinatal asphyxia

We measured plasma aldosterone levels in cord blood and peripheral blood collected 18-24 h after birth in 19 asphyxiated and 19 normal term newborn infants. The asphyxiated newborn infants had significantly higher aldosterone levels in cord blood than the normal newborn infants. At 18-24 h after birth there was no difference between the groups with respect to aldosterone levels. There was a positive significant correlation between aldosterone levels and PCO2 in cord blood by multiple linear regression analysis. There is a transient elevation of aldosterone levels in perinatal asphyxia.

[Coagulase-negative Staphylococcus sp. in blood cultures from infants less than 60 days old: infection versus contamination]

OBJECTIVE

The aim of this study was to determine the prevalence of infection versus the prevalence of contamination in infants less than 60 days old who had blood cultures positive for CoNS.

MATERIAL AND METHODS

Between February and June - 1993, a number of 45 blood cultures positive for CoNS from 41 patients were studied. Patients were classified in three groups according to their clinical and laboratorial data: I- infected patients, II- non-infected patients and III- dubious.

RESULTS

The results showed that 11 patients (26.8%) were included in group I, 25 (61%) in group II (contaminated blood cultures), and 5 (12.2%) in group III.

CONCLUSION

It is suggested that more than one blood culture should be requested before treatment with antimicrobials, avoiding unnecessary administration of antibiotics.

[The influence of intrapartum antibiotic therapy on the diagnosis of early-onset neonatal sepsis]

OBJECTIVE

To determine the influence of intrapartum antibiotic therapy on blood and secretion cultures of newborn infants suspected of early-onset sepsis.

MATERIAL AND METHODS

From August 1995 through July 1996, 69 sequential newborn infants with early-onset sepsis or septic syndrome were included in the study. All of them were followed for the end point: positivity of blood, urine, CSF, tracheal secretion or umbilical catheter cultures. The sample size was figured out to be 17 for each group, for a significant level of 5%.

RESULTS

Seventeen mothers were treated with antibiotic. Ampicillin alone or in association with other drugs was utilized in 70% of them. Urinary tract infection occurred in 9 mothers (53%), ammonites in 6, one mother had both and another one had erysipelas. Thirteen newborn infants had positive cultures in the group whose the mothers had not received antibiotic (n=52), none of the 17 newborn infants delivered by the mothers treated with antibiotic had any positive culture (p=0.0164). The relative risk of positive culture in a septic neonate if the mother is not treated with antibiotic is 12 times higher than if the mother is treated with antibiotic.

CONCLUSION

The use of intrapartum antibiotic in newborn infants with early-onset sepsis or septic syndrome may cause a negativity of cultural exams, increasing the difficulty of the diagnosis of early-onset neonatal sepsis.

Aldosterone cord levels in preterm newborn infants

We measured umbilical cord aldosterone concentrations in 64 premature newborn infants. The median serum aldosterone level was 74.5 ng dl-1 (range 22-280 ng dl-1). Of the studied perinatal factors, only gestational age and birthweight presented a significant influence on the umbilical cord aldosterone levels. Newborn infants with a gestational age of over 34 weeks and a birthweight of over 2000 g had a significantly higher aldosterone cord level than those aged 34 weeks or younger and 2000 g or less in weight.

[Evaluation of umbilical cord pH and its relationship with Apgar score in term newborn infants]

The value of the Apgar score as an index of birth asphyxia has been recently questioned. The purpose of the present study is to evaluate the relationship between cord blood pH and Apgar score in term newborn infants.A cross-sectional study involving 76 term newborn infants was performed from March through September 1995 at the Obstetric Unit of Hospital de Clínicas de Porto Alegre. The blood samples were obtained from umbilical cord artery and vein at the moment of delivery. Infants were divided in three different groups according to the Apgar score: Group A (n=60): >or=7 at one and five minutes; Group B (n=13): < 7 at one minute and >or=7 at five minutes; Group C (n=3): < 7 at one and five minutes. The frequency of acidemia in Group A was 18.3% (11 newborn infants) considering arterial pH < 7.20 and 5% considering arterial pH <or= 7.10. Three newborn infants (23%) of Group B had arterial pH >or= 7.20 and nine (56.2%) had arterial pH > 7.10. None of the newborn infants in Group C had arterial pH > 7.10. The sensitivity and specificity values for Apgar score less than 7 at one minute for detection of fetal acidemia were, respectively, 54.1% and 94.1%. This study confirms a poor correlation between Apgar score and umbilical blood cord pH, even in a term newborn, and emphasizes the importance of obtaining umbilical cord pH to consider the diagnosis of perinatal asphyxia.

[Hyperkalemia in very low birthweight infants: incidence and associated factors]

The present study evaluated the incidence of hyperkalemia in premature babies born at the Hospital de Clínicas de Porto Alegre (birthweight <or= 1250 grams and gestational age <or= 32 weeks) during the first 72 hours of life in a one year period. The incidence of hyperkalemia was of 38.5% (potassium levels >or=6 mEq/l) and 15.4% with potassium levels subject to cardiac arrhythmia (>or= 6.7 mEq/l). The population was divided into two groups: group KN with potassium < 6 mEq/l (n=16) and group KE with potassium >or= 6 mEq/l (n=10). The hydroelectrolyte management and maintenance of neutral thermal environment was the same for both groups. Neither group received potassium in the first 36 hours of life. The KE group presented higher potassium levels during all the study. The mean birthweights of the groups were similar (KN = 963 gr; KE = 987 gr). The KN group presented a mean gestational age (29.3 weeks x 30.8 weeks) and Apgar Score in the first minute of life (3.18 x 5.7) significantly lower (p = 0.004 and p = 0,015 respectively) than the KE group. There were no significant differences between both groups in relation to the intraventricular hemorrhage, acidosis, hialine membrane disease, insulin level, glycemia, glycemia/insulin index, glomerular filtration rate, diurese, urinary potassium level, fractional sodium excretion, fractional potassium excretion and aldosterone tubular index. The level of aldosterone was significantly higher in the KE group (p = 0.029) within 24 hours of life (212.8 ng/dl x 110.2 ng/dl). It is suggested that none of the studied factors is responsible for the non-oliguric hyperkalemia of the very low birthweight newborn infant, stressing, however, that the serum potassium level must be carefully controlled in those infants.

[The influence of the mode of delivery on the umbilical cord serum aldosterone levels in preterm newborn infants]

The influence of the mode of delivery on the umbilical cord serum aldosterone levels in preterm newborn infants was studied. Sixty-four newborn infants gestational age less than 37 weeks were sequentially included in the study. Umbilical cord blood was collected just after birth and the aldosterone level was measured by radioimmunoassay. The median aldosterone level of the whole studied sample was 74.5 ng/dl (range: 22.00-280.00 ng/dl). The aldosterone level of the 31 newborn infants delivered vaginally was similar of the 33 newborn infants delivered by cesarean-section. When the cesarean group was subdivided in presence or not of labor prior to delivery, the aldosterone levels of those delivered after labor was significantly higher than those without labor. It is suggested that some event associated to the mode of delivery or the presence of labor prior to delivery may influence aldosterone levels in preterm newborn infants.

[Decision making about the child in CIU--participation of the family]

This paper focuses attention on the moral and ethical principles in the treatment of a very sick newborn infant and child. Special attention is given to the risk benefit balance of the employment of sophisticated technology with the purpose of prolonging the survival of a possible handicapped child. The authors analyzed the different ways of facing this problem according to different cultural backgrounds. The concept of a terminal patient is not applied to the neonatal period. The principle of autonomy is discussed, and the familiar feelings are analyzed.

Fetal and neonatal cortical adrenal function in birth asphyxia

Eighteen newborn infants, gestational age between 36 and 42 weeks with birth asphyxia were compared with 23 normal newborn infants to determine serum cortisol and dehydroepiandrosterone sulfate levels in cord blood and in venous blood samples collected 12-18 hours after birth. Both groups were similar in gestational age, birthweight, proportion of small for gestational age and large for gestational age infants, proportion of infants delivered by cesarean section with and without labor, and proportion of mothers with pre-eclampsia. There was no antenatal exposure to corticosteroid. The asphyxiated newborn infants had a significantly higher mean cord serum level of cortisol, and a significantly lower mean cord serum level of dehydroepiandrosterone sulfate than the control group. Mean serum cortisol and dehydroepiandrosterone sulfate levels collected 12-18 hours after birth were similar between both groups. It is suggested that elevated cord serum level of cortisol is related to birth asphyxia stress stimulating the adrenal definitive zone, and the low cord serum level of dehydroepiandrosterone sulfate is secondary to a transient hypoxemic-ischemic insult to the adrenal fetal zone.

Early diagnosis of ABO haemolytic disease of the newborn

To assess the usefulness of cord blood tests in diagnosing ABO-haemolytic disease of the newborn (ABO-HDN), 132 term, adequate for gestational age (AGA) neonates were evaluated. The tests studied and their significant results were: quantitative elution test (greater than or equal to 1/16), direct Coombs test (positive), bilirubin concentration (greater than or equal to 4 mg/dl). In none of the 56 O+ newborn infants delivered by O+ women were the results of any test positive. Of the 76 A+ and B+ newborn infants delivered by O+ women, 17 (22%) developed ABO-HDN. When the combined result of any two tests was positive, the sensitivity, the specificity and the positive predictive accuracy for the diagnosis of ABO-HDN was higher than for any one of the isolated tests. The probability that ABO-HDN was present when the results of at least two cord blood tests were positive was 70%, and the probability that ABO-HDN was not present when less than two cord blood tests gave positive results was 93%. It is suggested that the combination of quantitative elution test, bilirubin concentration and direct Coombs test in the cord blood is useful for an early diagnosis of ABO-HDN.

Congenital Wilms' tumor associated with consumption coagulopathy and hyperbilirubinemia

A case of a term newborn infant with a congenital Wilm's tumor who developed severe jaundice and consumption coagulopathy is reported. After the removal of the tumor, the clotting factors became normal and the jaundice resolved. It is suggested that there was an association between the presence of the tumor and hemolysis and consumption coagulopathy.

Umbilical cord dehydroepiandrosterone sulfate and cortisol levels in preterm infants born to pre-eclamptic mothers

The influence of early-onset pre-eclampsia upon the umbilical cord serum levels of cortisol and dehydroepiandrosterone sulfate was studied in fifty-one preterm infants not exposed prenatally to corticosteroids. Preterm infants born to pre-eclamptic mothers (group A) presented lower dehydroepiandrosterone sulfate levels than preterm infants born to non-preeclamptic mothers (group B). The umbilical cord serum levels of cortisol were similar between both groups. It is suggested that the decrease in the cord serum levels of dehydroepiandrosterone sulfate in preterm infants of pre-eclamptic mothers plays an important role in the pathogenesis of the subnormal maternal urinary estriol excretion, and that the accelerated pulmonary and cerebral maturation of preterm infants born to pre-eclamptic mothers is not explained by an increased fetal serum cortisol concentration.

The influence of labor and delivery on preterm fetal adrenal function

The influence of labor and route of delivery upon umbilical cord serum levels of cortisol and dehydroepiandrosterone sulfate in one hundred sixty-nine preterm infants not exposed prenatally to corticosteroids was studied. Vaginally born infants (group A, n = 89) presented a higher mean cord cortisol and dehydroepiandrosterone sulfate concentrations than those delivered by cesarean section (group B, n = 80). Although there were no differences in cortisol and dehydroepiandrosterone sulfate levels between infants delivered by cesarean section after spontaneous onset of labor (group B-I, n = 42) and those without labor (group B-II, n = 38), the mean cortisol and dehydroepiandrosterone sulfate concentrations were higher in group A than in group B-I. There was a correlation between umbilical cord cortisol and dehydroepiandrosterone sulfate levels. It is concluded that there is no association between the presence of labor and high cord serum levels of cortisol and dehydroepiandrosterone sulfate and there is an association between vaginal delivery and high cord cortisol and dehydroepiandrosterone sulfate levels in preterm infants. It is suggested that the stress of vaginal delivery stimulates the secretion of fetal cortisol and dehydroepiandrosterone sulfate in preterm infants.

Umbilical cord cortisol and prolactin levels in preterm infants. Relation to labor and delivery

The influence of labor and route of delivery upon the umbilical cord serum levels of cortisol and prolactin in ninety-nine preterm infants not exposed prenatally to corticosteroids was studied. Vaginally born infants (group A) presented a higher mean cord cortisol concentration than those delivered by cesarean section (group B); mean prolactin values, however, were not different between both groups. Although there was no difference in cortisol and prolactin levels between infants delivered by cesarean section after spontaneous onset of labor (group B-I) and those without labor (group B-II), the mean cortisol concentration was significantly higher in group A than in group B-I. The mean prolactin levels did not differ among all the studied groups. It is concluded that there is no association between presence of labor or route of delivery and cord serum levels of prolactin, there is no association between spontaneous preterm labor and cord cortisol values and there is an association between vaginal delivery and high cord cortisol levels in preterm infants. It is suggested that the increase in serum cortisol levels does not precede the initiation of preterm parturition but it is secondary to the stress caused by vaginal delivery.

The hyaline membrane disease-intraventricular hemorrhage relationship in the very low birth weight infant: perinatal aspects

A large retrospective clinical study is reported confirming pathologic studies upon the effect of hyaline membrane disease on the occurrence of intraventricular hemorrhage in very low birth weight infants. Two hundred and twenty infants with birth weight less than or equal to 1 500 g and gestational age less than or equal 32 weeks were studied. Infants with hyaline membrane disease (112) had 56% incidence of intraventricular hemorrhage whereas of those without hyaline membrane disease (108) only 31% developed intraventricular hemorrhage (p less than 0.001). When controlled for gestational age, the more immature infants (less than or equal to 1 000 g) exhibited no difference in the occurrence of intraventricular hemorrhage whether hyaline membrane disease coexisted or not. In the 1 001-1 500 g group, the occurrence of hyaline membrane disease with intraventricular hemorrhage was significant (p less than 0.001). The association of lower Apgar scores and the influence of intermittent positive pressure ventilation in infants with intraventricular hemorrhage is discussed. Extreme immaturity negates all perinatal clinical expertise in determining neonatal outcome. Therefore, carrying pregnancies beyond 28 weeks gestation is mandatory. Beyond 28 weeks, pulmonary maturity and the influence of therapeutic modalities and maternal transport become increasingly important.

Blood pesticide concentration in mothers and their newborn infants. Relation to prematurity

An association between high DDT cord blood levels and prematurity was investigated. Pregnant women with good health and nutritional condition, negative history of past occupational exposure to DDT and absence of recent exposure to DDT were investigated as well as their appropriate for gestational age neonates. A total of 54 maternal-infant pairs were studied and divided in two groups: A-term deliveries (30 pairs), B-preterm deliveries (24 pairs). There was no difference in DDT blood levels between pregnant women of both groups. There was, however, a significant difference in DDT cord blood levels between term and preterm infants, as well as between maternal and neonatal blood levels in both groups. DDT cord blood levels correlated negatively with infants' birth weights. We suggest that there is an association between prematurity and high DDT cord blood levels in a non-occupationally exposed population and the amount of fetal adipose tissue is an important factor determining the cord blood level of this pesticide. We cannot rule out a cause-effect association between high DDT cord blood level and prematurity.

An association between retinopathy of prematurity and intraventricular hemorrhage in very low birth weight infants

An association between cicatricial retinopathy of prematurity and intraventricular hemorrhage in very low birth weight infants was investigated retrospectively. Newborns were studied who weighed less than or equal to 1500 g at birth, who were less than or equal to 32 weeks gestational age and appropriate by weight, and admitted in the first 24 hours of life to our Neonatal Intensive Care Unit. Diagnosis of retinopathy of prematurity was made by retinal examination at approximately 4 weeks of age. Diagnosis of intraventricular hemorrhage was made by computerized tomography and clinical findings. A total of 138 infants were studied and divided into two groups: (A) birth weight less than or equal to 1000 g (31); (B) birth weight 1001--1500 g (107). There was a statistically significant association between cicatricial retinopathy of prematurity and intraventricular hemorrhage in both groups. There were no statistical differences between birth weight, gestational age, duration of oxygen therapy, highest oxygen concentration received, Apgar scores, incidence of hyaline membrane disease and patent ductus arteriosus between cicatricial retinopathy of prematurity and no retinopathy of prematurity patients in either group. This association may be an important consideration in the pathogenesis of both vascular diseases.

Hyaline membrane disease and intraventricular haemorrhage in small for gestational age infants

19 small for gestational age (SGA) infants with gestational ages less than or equal to 32 weeks were matched with 19 appropriate for gestational age (AGA) preterm neonates with similar risk factors for intraventricular haemorrhage and hyaline membrane disease. Gestational age, 1- and 5-minute Apgar scores, type of delivery, survival rate, use of corticosteroids before delivery, sex, twinning, presence of premature rupture of membranes, and birth date were comparable in the two groups. Gestational age of both groups was 30 (+/- 1.8) weeks, and birthweights were 919 (+/- 202) g (SGA group) and 1268 (+/- 212) g (AGA group). The incidences of hyaline membrane disease and intraventricular haemorrhage were different: 74 and 42% respectively for AGA neonates, 5 and 11% respectively for SGA infants. We suggest that a stressful environment in utero may enhance maturation and prevent hyaline membrane disease and intraventricular haemorrhage.

Use of indomethacin and its relationship to retinopathy of prematurity in very low birthweight infants

The relationship between the use of indomethacin, a prostaglandin inhibitor, for closure of patent ductus arteriosus (PDA) and the occurrence of retinopathy of prematurity was investigated retrospectively. 63 preterm infants less than or equal to 1500 g who were less than or equal to 32 weeks' gestational age, appropriate weight for gestational age, with a diagnosis of PDA, and admitted during the first 24 hours of life were studied. Diagnosis of retinopathy was made by retinal examination when each infant was about 4 weeks. Diagnosis of PDA was made by clinical, radiological, and echocardiographic findings. 15 patients were treated with indomethacin because of severe congestive heart failure. There were no differences between gestational ages, birthweights, duration of oxygen therapy, or incidence of retinopathy in treated and untreated patients. We suggest that the use of indomethacin for PDA closure does not increase the incidence of retinopathy in very low birthweight infants.