Factors associated with periventricular haemorrhage in very low birthweight infants.

Periventricular haemorrhage was diagnosed in vivo in 20 of 29 consecutively admitted infants of birthweight below 1500 g using an ultrasound scanner. Ten (51%) infants with haemorrhages survived. Mortality was related to the extent of the bleeding. Statistically significant associations with respiratory distress, ventilator therapy, metabolic acidosis, and hypercapnia were observed, lending support to their role in the pathogenesis of periventricular haemorrhage.     

Perinatal factors, periventricular haemorrhage and mortality in very low birthweight infants

In a population of 225 very low birthweight infants born over a 21 month period the cerebroventricular system was scanned by ultrasound. One third of the infants developed a periventricular haemorrhage; in 41% of infants the haemorrhage was detected before an hour of age and 66% of all haemorrhages occurred within the first 24 hours. Statistically significant associations with periventricular haemorrhage included vaginal delivery, endotracheal intubation and intravenous sodium bicarbonate when this was administered in the first 24 hours. In a stepwise regression analysis, however, these and other potentially significant variables added little to the total accountable variance. A similar analysis of perinatal factors and mortality revealed that decreasing gestation was the major association with death.     

Perinatal factors, periventricular haemorrhage and mortality in very low birthweight infants

In a population of 225 very low birthweight infants born over a 21 month period the cerebroventricular system was scanned by ultrasound. One third of the infants developed a periventricular haemorrhage; in 41% of infants the haemorrhage was detected before an hour of age and 66% of all haemorrhages occurred within the first 24 hours.
Statistically significant associations with periventricular haemorrhage included vaginal delivery, endotracheal intubation and intravenous sodium bicarbonate when this was administered in the first 24 hours. In a stepwise regression analysis, however, these and other potentially significant variables added little to the total accountable variance. A similar analysis of perinatal factors and mortality revealed that decreasing gestation was the major association with death.     

Severe liver haemorrhage during laparotomy in very low birthweight infants

A review is presented of severe liver haemorrhage as a serious complication in surgery on very low birthweight (VLBW) infants. Clinical data and pathological findings, as well as the outcome of the treatment, of five VLBW infants (<1000 g) who experienced liver haemorrhage during surgical exploration for necrotizing enterocolitis or spontaneous intestinal perforation were reviewed retrospectively. At the time of surgery, all infants had signs and symptoms of impending sepsis. The bleeding was predominantly "spontaneous" without obvious iatrogenic liver damage. In three infants, severe liver haemorrhage could be stabilized by early liver tamponade using absorbable thrombostatic sponges and polyglactin mesh. Conclusion: Intraoperative liver haemorrhage potentially life-threatening complication of surgery in preterm infants, which is not frequently investigated. Immediate perihepatic liver packing may be used to achieve adequate bleeding control.     

Intraventricular haemorrhage and the renin-angiotensin-aldosterone system in very low birthweight infants

Blood volume, plasma renin activity (PRA) and urine aldosterone excretion (UAE) were measured in ten very low birthweight infants who had a Grade 3 or 4 intraventricular haemorrhage (IVH) during the first 2 days after birth. Mean (range) birthweight was 950 (630-1500) g and gestational age was 27 (23-31) weeks. Nine infants were receiving assisted ventilation and one was breathing spontaneously. Eight IVH occurred on the first postnatal day and two on the second; seven were symptomatic and three asymptomatic. PRA was significantly higher than control values on Day 1 only; median 244 (range 91-654) ng/ml per h vs. 64 (4-259) ng/ml per h (P less than 0.01). Infants with symptomatic IVH in the preceding 8 h (n = 6) all had PRA greater than 300 ng/ml per h; none of these infants had received transfusions or volume expansion between IVH and PRA measurement. PRA was less than 100 ng/ml per h in the three infants with asymptomatic IVH and one infant with greater than 24 h interval between IVH and PRA measurement; three of these four had received transfusions prior to PRA measurement. UAE was not significantly different from control values on either Day 1 or Day 2. Blood volume at 22 +/- 3 h postnatal age ranged from 75 to 107 ml/kg. There was an inverse logarithmic correlation between PRA and blood volume (r = 0.883; P less than 0.005), with PRA values exceeding 300 ng/ml per h when blood volume was less than 90 ml/kg. UAE did not correlate with either PRA or blood volume.(ABSTRACT TRUNCATED AT 250 WORDS)     

Risk factors for intraventricular haemorrhage in very low birth weight infants

Objective: In a prospective study at Uludag University Hospital, 120 premature infants with birthweights of 1500 g or less were screened for intraventricular hemorrhage (IVH) using cranial ultrasound. With the purpose of studying the incidence of IVH, the associated risk factors for these neonates were considered.Methods : We studied all the very low birth weight infants admitted in our neonatal unit. We examined the following variables as risk factors for IVH: sex, birth weight, gestational age, Apgar score, mechanichal ventilation, hypercapnia, use of antenatal steroids, tocolytic drugs, vaginalversus cesarean section delivery, and inbornversus outborn status, vasopressor infusion (any vasoactive drug such as dopamine, dobutamine, or epinephrine) not associated with resuscitation, and surfactant administration.Results :The incidence of IVH was 15% (18/120), 50% grade I (9/18), 17% grade II (3/18), 11 % grade III (2/18), and 22% grade IV (4/18). IVH occurred mainly in the first week of life (78%; 14/18). The significant risk factors for IVH were found to be prematurity, outborn status, low 5 minute Apgar score, vaginal delivery, hypercapnia, mechanical ventilation, hypotension, and use of vasopressors on the day of admission. Significant protective factors against IVH included antenatal steroid therapy, cesarean section, magnesium sulfate tocolysis, increasing gestational age, and increasing birth weight.Conclusion: Our results concur with the notion that a tertiary center is the optimal location for delivery of the high risk neonate. Transportation of infantsin utero to a perinatal center specializing in high risk-deliveries results in a decreased incidence of IVH when compared to infants transported postnatally. Aggressive resuscitation, with avoidance of hypercarbia, and rapid restoration of hypovolemia could potentially reduce the incidence of PVH/IVH     

Blood pressure and cerebral haemorrhage and ischaemia in very low birthweight infants

Hourly blood pressures were recorded directly in 131 very low birth weight infants in intensive care during the first 4 days of life. Cranial ultrasound evidence of intraventricular haemorrhage correlated well with periods of hypotension, but not of hypertension. Ischaemic lesions did not correlate with periods of hypotension, but were associated with previous haemorrhage. The findings suggest that hypotension predisposes to primary intraventricular haemorrhage and that later parenchymal ischaemic lesions relate to local factors rather than hypotension.     

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=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.     

Cerebral palsy in very low birthweight infants.

Eighty one very low birthweight survivors with cerebral palsy were matched with controls by sex, gestational age, and place of birth. Using discriminant analysis, the perinatal profiles for infants with cerebral palsy and their controls were shown to differ significantly. When infants with various types of cerebral palsy were analysed with their controls the discriminating variables differed. Diplegic infants could be differentiated from controls on antenatal variables alone, but significant discrimination of hemiplegic and quadriplegic infants required the addition of postnatal variables. Cranial ultrasound appearances differed appreciably between types of cerebral palsy. Future studies should differentiate between types of cerebral palsy and include ultrasound data. Cerebral palsy in very low birthweight infants is unlikely to prove a useful outcome indicator for neonatal intensive care.     

Low prevalence of large intraventricular haemorrhage in very low birthweight infants carrying the factor V Leiden or prothrombin G20210A mutation

The influence of genetic factors that increase coagulation on the extension of intraventricular haemorrhage (IVH) in very low birthweight infants has not been studied previously. This study investigated the frequency and effect of the factor V Leiden and prothrombin G20210A mutations in a population-based cohort of 305 preterm infants with a birthweight below 1500 g. The overall prevalence of IVH was similar in infants with ( n = 43) and without ( n = 262) prothrombotic mutations (18.6% vs 16.4%, respectively). However, infants with prothrombotic mutations had a significantly reduced risk of developing extension to IVH grade II or more [ p = 0.023, odds ratio (OR) 0.11, 95% confidence interval (CI) 0.02-0.5]. The carrier state of a factor V Leiden or prothrombin G20210A mutation was still predictive for a low rate of IVH grade II-IV if possible confounding variables were included in a multivariate regression model (OR 0.12; 95%CI: 0.017- 0.86).     

Central venous catheterisation in very low birthweight infants.

Forty two premature babies (mean birth weight 980 g, mean gestation 27.6 weeks) had central venous lines inserted at a mean age of 10 days through the internal jugular vein because of poor peripheral venous access and for purposes of parenteral feeding and minimal handling. Eight babies died from complications of prematurity and four from septicaemia with a central line in situ, but the other 30 babies had lines in place for a mean of 20 days. A mean weight gain of 17.5 g/kg/day was recorded. Eight babies showed signs of infection at a mean of 22 days after insertion of the line. The other complications were thrombosis related to the catheter (three cases), embolisation (two), and hydrocephalus related to superior vena caval thrombosis (one). The policy of management is outlined, and the risks and benefits of the technique are analysed.     

Phototherapy for hyperbilirubinaemia in very low birthweight infants.

Phototherapy was used to treat 20 newborn babies whose birthweight was below 1500 g and whose plasma bilirubin exceeded 8 mg/100 ml. The plasma bilirubin level was maintained below 13 mg/100 ml except in 4 babies whose level exceeded 13 mg/100 ml before treatment was started. In 60% of an untreated group of larger babies previously reported the plasma bilirubin level exceeded this figure. Phototherapy seems to control the plasma bilirubin level satisfactorily in very low birthweight infants, but frequent measurements on the second and third days of life are advised in order that treatment may be started promptly when it exceeds 8 mg/100 ml.     

Air embolism in ventilated very low birthweight infants.

Five cases of air embolism in ventilated very low birthweight infants are reported. In all cases the outcome was fatal with the babies dying at about 15 hours of age.     

Pulmonary interstitial emphysema in very low birthweight infants.

Forty six of 142 infants weighing less than 1500 g at birth, who had chest radiographs in the first 5 days of life, developed pulmonary interstitial emphysema (PIE) and in 19 this occurred in the first 24 hours. PIE was seen more frequently in infants weighing less than 1000 g at birth (24 of 57) than in those weighing 1000-1500 g (22 of 85). Ventilation for hyaline membrane disease was strongly associated with PIE, and only babies who were resuscitated, or ventilated, or had hyaline membrane disease developed the disorder. Most pneumothoraces were preceded by x-ray appearances of PIE (17 of 21). Mortality was increased in ventilated infants who developed PIE and was high in those with severe x-ray changes.     

Bronchopulmonary dysplasia in very low birthweight infants

The incidence, clinical presentation and severity of bronchopulmonary dysplasia (BPD) in 110 consecutive very low birthweight (VLBW) infants admitted to the National University Hospital Neonatal Intensive Care Unit between October 1985 and January 1989 is reviewed. Thirty-two infants died, giving an overall survival rate of 70.9%. Sixty infants (54.4%) required mechanical ventilation in the first week of life; 24 (40%) of these infants died. Of the 36 survivors, 23 required oxygenation at 28 days of life and 21 fulfilled the criteria for BPD (35% of the 60 ventilated and 58% of the survivors). The incidence of BPD in all VLBW infants is 19% and of VLBW survivors 27%. Birthweight and gestational age appear to be important determinants. All the survivors in the 501-750 g birthweight group developed BPD compared to 6.25% in those above 1250 g. None of those greater than 30 weeks gestation developed BPD. Two forms of BPD were observed; the 'severe' group presented radiologically with chest radiographs characteristic of Stage IV BPD, while the 'mild' group with small or normal sized lungs demonstrated irregular strands of radio-densities alternating with areas of normal or increased lucency. The duration of mechanical ventilation and oxygen dependency were significantly longer in the 'severe' group, with the mean maximum peak inspiratory pressure, mean airway pressure, and FiO2 required in the first week of life being also significantly higher. Hyaline membrane disease was the main cause of respiratory failure requiring ventilation. The other causes were persistent pulmonary hypertension (1) and apnoea of prematurity (3); all of the latter developed only mild BPD.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bronchopulmonary dysplasia in very low birthweight infants

Twenty-four (6%) of 375 infants with birthweights less than or equal to 1500g developed bronchopulmonary dysplasia (BPD); 16 (15%) of 107 in those less than or equal to 100g and 8 (3%) of 268 in those greater than 1000g. The incidence was 10% in those who required assisted ventilation. Perinatal asphyxia, significant respiratory distress, pulmonary interstitial emphysema and patent ductus arteriosus were statistically more common in BPD infants compared with the remaining 351 very low birthweight infants. Hyaline membrane disease was the primary respiratory disease in 54% of BPD infants. The mean durations of oxygen and ventilatory therapy were 68 days and 37 days respectively. Twenty-nine percent did not require more than 60% oxygen for over 24 hours. Only 38% required a peak airway pressure of over 30 cmH2O. Early postnatal growth was satisfactory on parenteral nutrition support. No perinatal factor was found to be predictive of death from BPD. The prolonged duration of hospital treatment has obvious implications to the psychosocial and economic costs of BPD.     

Late-onset neutropenia in very low birthweight infants

AIM: To evaluate the incidence and duration of late-onset neutropenia (defined as an absolute neutrophil count (ANC) <1500 mm(-3) at a postnatal age of >3 wk) in a population of infants with birthweight <2000 g, and to determine whether copper deficiency, a possible cause of both anemia and neutropenia, may be associated with this complication. METHODS: Complete blood cell count and differential were assessed in 247 low (LBW) and very low birthweight (VLBW) infants who were discharged after 3 wk of life. In neutropenic infants plasma copper and ceruloplasmin levels were also measured. RESULTS: Late-onset neutropenia was detected in 11 out of 147 VLBW infants (7.5%) and in 7 out of 127 LBW infants (5.5%). A neutrophil count of <1000 mm(-3) was observed in 14 infants (5.1%). A significantly lower gestational age was found in neutropenic infants compared with non-neutropenic infants. In neutropenic infants ANCs were significantly correlated with hemoglobin and hematocrit. In addition, a significant negative correlation was found between neutrophil and reticulocyte counts. Plasma copper concentration was significantly correlated with birthweight. Oral copper sulfate was administered to infants with plasma copper concentration <50 microg dl(-1), and did not seem to affect ANC, hemoglobin, hematocrit or reticulocyte counts. CONCLUSION: Late-onset neutropenia appears to be a benign condition that is not associated with any particular complication and does not require specific treatment. Reference ranges after the early neonatal period and during the first few months of life in LBW and VLBW infants should probably be set at lower values.