Persistent Pulmonary Hypertension and Histologic Chorioamnionitis in Preterm Infants: Controlled Study

Persistent pulmonary hypertension (PPHN) of the newborn is one of the most challenging acute disorders of postnatal transition with substantial morbidity and mortality. The aim of the study was to find if there is an association between persistent pulmonary hypertension and histologic chorioamnionitis in preterm infants. 27 preterm infants with echocardiographic evidence of PPHN within the first 3 days of life were eligible for the study. A matched control group of 27 patients was chosen according to gestational age, date of birth, and gender. Data collection included the need for respiratory support, use of nitric oxide oxygen supplementation, duration of rupture of membranes, blood culture, blood count, and C-reactive protein levels at birth and 12 h. Maternal clinical and laboratory data suggesting clinical chorioamnionitis Placentas of both groups were examined. Differences between groups were analyzed using two-tail t test, Kolmogorov-Smirnov test, Chi-square test. No statistically differences were found in all parameters compared between groups, except for a higher number of patients in the PPHN group who were treated by oxygen supplementation. An association was not found between the incidence of HCA and echocardiographic PPHN in preterm infants in the first 3 days of life.

Inflammatory Response in Preterm Newborns Born after Prolonged Premature Rupture of Membranes: Is There a Correlation with Placental Histological Findings?

BACKGROUND

Preterm birth is the leading cause of morbidity and mortality among neonates in the United States. Early recognition of sepsis in this population is a challenging task since overt clinical signs can be difficult to determine. C-reactive protein (CRP), one of the most frequently non-specific used laboratory test, can indirectly aid the diagnosis of neonatal sepsis.

OBJECTIVES

To evaluate the relationship between histological findings in the placenta of preterm newborns born after prolonged rupture of membranes, CRP levels, and blood cultures.

METHODS

Medical records were reviewed of all preterm newborns born after prolonged premature rupture of membranes at a medical center in Israel between 2011 and 2014.

RESULTS

Of 128 newborns with prolonged rupture of membranes, 64 had evidence of histological chorioamnionitis (HCA). Gestational age, birth weight, and Apgar scores were significantly lower, while CRP levels (on admission and 10-12 hours post-delivery) were significantly higher in preterm newborns born to mothers with histological evidence of chorioamnionitis, but values were within normal ranges. Duration of the rupture of membranes and white blood cell counts did not differ between groups.

CONCLUSIONS

CRP levels taken on admission and 10-12 hours after delivery were higher when HCA was present, but since there was a substantial overlap between those with and without HCA and the values for most were within normal range, the differences were not enough to serve as a tool to diagnose placental histological chorioamnionitis in preterm infants born after prolonged premature rupture of membranes and exposed to intrapartum antibiotics.

Rehospitalization Through Childhood and Adolescence: Association with Neonatal Morbidities in Infants of Very Low Birth Weight

OBJECTIVE

To evaluate the impact of major neonatal morbidities on the risks for rehospitalization in children and adolescents born of very low birth weight.

STUDY DESIGN

An observational study was performed on data of the Israel Neonatal Network linked together with the Maccabi Healthcare Services medical records. After discharge from the neonatal intensive care unit, 6385 infants of very low birth weight born from 1995 to 2012 were registered with Maccabi Healthcare Services and formed the study cohort. Multivariable negative binomial regression models were calculated to estimate the adjusted relative risk (aRR) and 95% CI for hospitalization.

RESULTS

Up to 18 years following discharge, 3956 infants were hospitalized at least once. The median age of follow-up was 10.7 years with total of follow-up of 67 454 patient years and 10 895 hospitalizations. The risks for rehospitalization were increased significantly for each of the neonatal morbidities: surgical necrotizing enterocolitis (NEC), aRR 2.71 (95% CI 2.08-3.53), intraventricular hemorrhage grades 3-4, 2.13 (1.85-2.46), periventricular leukomalacia (PVL), 1.83 (1.58-2.13), bronchopulmonary dysplasia, 1.94 (1.72-2.17), and retinopathy of prematurity stages 3-4, 1.59 (1.36-1.85). During the first 4 years, children with surgically treated NEC, intraventricular hemorrhage, PVL, or bronchopulmonary dysplasia had 1.5- to 2.5-fold greater risks for hospitalization compared with those without the specific morbidity. In the 11th-14th and 15th-18th years, respectively, surgically treated NEC was associated with a 3.05 (1.32-7.04) and 3.26 (0.99-10.7) aRR for hospitalization, and PVL was associated with a 2.67 (1.79-3.97) and 3.47 (2.03-5.92) aRR for hospitalization.

CONCLUSIONS

Specific major neonatal morbidities as well as the number of morbidities were associated with excess risks of rehospitalization through childhood and adolescence.

Timing of external ventricular drainage and neurodevelopmental outcome in preterm infants with posthemorrhagic hydrocephalus

OBJECTIVE

To delineate the impact of early (≤ 25 days of life) versus late (> 25 days) external ventricular drainage (EVD) on the neurodevelopmental outcome of preterm infants with posthemorrhagic hydrocephalus (PHH) following intraventricular hemorrhage (IVH).

METHODS

We retrospectively categorized 32 premature infants with PHH into two groups according to whether they underwent early (n = 10) or late (n = 22) EVD. We administered the Battelle Developmental Inventory II and a neuromotor examination (median age, 73 months, range: 29-100).

RESULTS

In adjusted comparisons, early EVD was associated with better scores than late EVD in adaptive (79 ± 22.6 vs. 58.8 ± 8.1, P = .01), personal social (90.7 ± 26 vs. 67.3 ± 15.9, P = .02), communication (95.4 ± 27.5 vs. 69.6 ± 20.5, P = .04) and cognitive (78.9 ± 24.4 vs. 60.7 ± 11.5, P = .055) functions. Three (30%) early EVD infants had severe (<2.5 standard deviation) cognitive disability compared to 18 (82%) late EVD infants (P = .03). The incidences of cerebral palsy and neurosurgical complications were equal for the two groups. Subgroup analyses suggested that early EVD was beneficial in infants with original grade III IVH (n = 15, P < 0.05), but that it had no beneficial effects in infants with prior parenchymal injury (n = 17, P = NS).

CONCLUSION

In this small retrospective series, early EVD is associated with lower rates of cognitive, communication and social disabilities than later EVD in infants with PHH without prior parenchymal injury. A randomized prospective trial is warranted.

No longer pregnant, not yet a mother: giving birth prematurely to a very-low-birth-weight baby

In this article we present the findings of a qualitative examination of 30 mothers of very-low-birth-weight babies. Interviews conducted with the mothers when the babies were still in neonatal hospitalization show that virtually all the mothers described their delivery both as a traumatic event, and as a nonevent in which they felt that they barely participated. Most of them blamed themselves for not carrying full term, some blamed others, and some believed the premature delivery saved their baby's life. Following their truncated pregnancies, their "nonparticipation" in the delivery, and their separation from their newborn immediately after the delivery, virtually all the women reported difficulty grasping that they were mothers. Many reported a sense of loss, emptiness, and frustration that the baby was no longer inside. The women took a variety of measures, including magical means and parenting behaviors, to safeguard their vulnerable babies and to become mothers within the constraints of the neonatal unit.

Flexible fiberoptic bronchoscopy--a bedside technique for neonatologists

BACKGROUND

Flexible fiberoptic bronchoscopy (FFB) is an under-used technology in neonates, mostly performed by external consultants from either pulmonology or otolaryngology. Modern ultra-thin scopes offer the neonatologist new diagnostic and therapeutic opportunities at the bedside.

OBJECTIVE

To describe the diagnostic value, therapeutic potential, and safety profile of FFB in neonates when performed by neonatologists as a bedside procedure.

METHODS

This was a retrospective case series that included 19 term and preterm infants who underwent FFB in two Neonatal Intensive Care Units (NICU).

RESULTS

Twenty-five procedures were performed for the following indications: suspected airway pathology (15); BAL (8), noisy breathing (4), aid to difficult endotracheal intubation (1), investigation for failure of weaning from ventilation (6), and evaluation of tracheotomy or endotracheal tube patency (5). Thirteen procedures had more than one indication. Airway pathology was observed in 15 of 25 (60%) procedures. Treatment of atelectasis was successful in 7 of 10 cases. BAL culture results influenced antibiotic therapy in 5 of 10 cases (50%). No procedure-related mortality occurred. One serious adverse event (1/25, 4%), namely bilateral pneumothorax occurred 1 h after FFB.

CONCLUSIONS

FFB is a useful and safe procedure that belongs in the neonatologists' armamentarium.

Reducing blood transfusion requirements in preterm infants by a new device: a pilot study

OBJECTIVE

To test a new device designed to salvage red blood cells (RBCs) from blood samples drawn from preterm infants, with the intent of decreasing blood loss and lowering the requirements for RBC transfusions.

DESIGN

A case-controlled pilot study was conducted in two Israeli neonatal intensive care units in large municipal hospitals. Twenty low-birthweight preterm infants were randomly and equally divided into the ErythroSave group or a control group. All blood tests in the study group (except for complete blood count and coagulation parameters) were obtained during the first week of life by the new device in the study group and by ordinary syringes in the control group. The main outcome measure was the total number of units of blood needed.

RESULTS

The average volume of blood obtained for laboratory analyses from each infant was 27 mL in the ErythroSave group and 24 mL in controls (not significant). The average volume of transfused packed cells was 6.4 mL for the ErythroSave group and 21.3 mL for the controls (p = 0.008).

CONCLUSION

The use of ErythroSave for sampling blood significantly reduced blood transfusion requirements in premature infants compared to sampling by conventional syringes.

The outcome of preterm neonates with intraventricular hemorrhage delivered with intravenous meperidine or epidural analgesia

We aimed to study, retrospectively, the neonatal outcome of 45 preterm neonates with intraventricular hemorrhage (IVH) who were delivered vaginally with intravenous meperidine (n = 23) or epidural analgesia (n = 22). Neonates in the epidural group had a better outcome in terms of a first-minute Apgar score of 7 or less, in 31% vs 69% (P = 0.001); 5-min Apgar score of 7 or less, in 18% vs 82% (P = 0.003); a lower incidence of respiratory distress syndrome (RDS; 23% vs 30%; P = 0.03); a lower dopamine requirement during the first neonatal week (13% vs 72%; P = 0.01); and a higher survival rate (91% vs 58%, respectively; P = 0.008). It is concluded that preterm neonates with IVH had a better outcome when delivered to mothers receiving epidural analgesia as compared to those receiving intravenous meperidine.

Optimizing high-frequency-oscillation ventilation using acoustic parameters of the newborn lung: a feasibility study

Ventilation using high-frequency oscillation (HFO) has become a standard care for the ventilatory management of critically ill newborns. In recent years, there has been growing recognition that maintenance of an optimal lung volume during high-frequency oscillation plays an important role in minimizing ventilator-induced lung injury. The primary variable affecting lung volume is the mean airway pressure (MAP). To effectively maintain lung recruitment and optimal gas exchange without overstretching (or collapsing) the lung, MAP should be set between two well defined points in the pressure-volume curve of the lung. To determine optimal MAP during high frequency ventilation, an acoustic monitoring system was developed and tested. The system was based on transmission of audible acoustic bursts and reception of echoes from the lungs. The results suggest that these acoustic measurements reflect the mechanical properties of the lungs. The acoustic measurements indicated an increase in lung volume following the administration of exogenous surfactant into the lungs as expected. Hysteresis in the amplitude of acoustic reflection was also measured as expected. Despite the fact that we had no "gold standard" to compare with, our results suggest that acoustic properties of the lung as measured by our system, have the potential to indicate the degree of lung recruitment during HFO and to define the optimal region of MAP.

Risk factors for seizures in very low birthweight infants with periventricular leukomalacia

This population-based observational study aimed to determine the perinatal factors that were associated with the occurrence of seizures in very low birthweight infants with periventricular leukomalacia. The study sample consisted of 545 infants from the Israel National Very Low Birthweight Infant Database, gestational age 24 to 36 weeks, who survived beyond 28 days of age, in whom a late cranial ultrasonographic examination was performed and in whom periventricular leukomalacia was diagnosed. To evaluate the association between periventricular leukomalacia and confounding variables on the occurrence of seizures, the chi-square test, univariate analysis, and a logistic regression model were used. Of the 545 infants who developed periventricular leukomalacia, 102 (18.7%) had seizures. Significant independent predictors of seizures among these infants were decreasing gestational age, intraventricular hemorrhage, posthemorrhagic hydrocephalus, sepsis, and necrotizing enterocolitis. Infants with both sepsis and necrotizing enterocolitis had a 4.6-fold increased risk of seizures, further suggesting a possible role of infection in the pathogenesis of brain injury in preterm infants.

An outbreak of new, nonmultidrug-resistant, methicillin-resistant Staphylococcus aureus strain (sccmec type iiia variant-1) in the neonatal intensive care unit transmitted by a staff member

A methicillin-resistant Staphylococcus aureus (MRSA) strain was recovered in a neonatal intensive care unit from 3 blood and 3 sputum specimens with antibiotic susceptibility profile characteristic of community-acquired MRSA. Epidemiologic survey resulted in isolation of an identical strain from the nares of one nurse. All isolates carried a new SCCmec type IIIA variant. Treatment of the nurse with topical mupirocin resulted in cessation of the outbreak.

Neonates with extra-renal pelvis: the first 2 years

Extra-renal pelvis (ERpel) is a common ultrasonographic finding among neonates who have undergone recurrent ultrasound examinations for a better definition of prenatal renal pelvic dilatation. This study tries to determine whether or not ERpel has important prognostic implications. Seventy-nine neonates (17 female) were examined. All had a diagnosis of prenatal renal pelvis dilatation, which was shown by postnatal ultrasound to be ERpel. Sixty ERpel neonates were examined 1.5 months to 2.5 months after the ultrasound (US) diagnosis by both Tc-99m diethylene triamine penta-acetic acid (DPTA) dynamic renal scanning and (99m)Tc-pertechnetate direct cystography. Clinical assessment, urine cultures and renal ultrasound follow-up were maintained for 2 years. The proportion of urinary tract infections (UTIs) in patients with ERpel was compared with that of the total neonatal and infantile population with normal US scans in the region of our hospital. Associated minor congenital malformations were found in 12 of 79 neonates (15.2%). Four had a family history of ERpel. Among 60 neonates who underwent renal scanning, 36 (60%) were found to have urinary retention in the collecting system. Another nine (15%) had vesico-ureteral (VU) reflux, of which seven had urinary retention. Fifteen (25%) showed normal isotope imaging. Urinary tract infection was diagnosed in 16 ERpel neonates in whom only one exhibited VU reflux (grade 2). The incidence of neonatal UTI in the ERpel group was more than that of either neonatal or infantile UTI in those with normal US scans in the local population (20.2% vs 1.2% and 4.3%, respectively). Fifty-three infants completed a 2-year follow-up. Repeat renal ultrasonography indicated that one infant (1.8%) had developed bilateral hydronephrosis, 12 (22.6%) had unchanged findings, 18 (40%) showed an improvement (decrease of ERpel width or resolution in one side) and, in 22 (41.5%) infants, the condition had resolved. No clinical or kidney function deterioration was observed. Seven patients (13.2%) each had one episode of UTI during the 2-year follow-up period; none of them had VU reflux. Neonatal ERpel is more frequent in male infants. It is associated with greater rates of minor congenital malformations, VU reflux and UTI than in the general population of the same ages. The increased UTI incidence is not attributed to VU reflux.

Vacuum extraction and herpes simplex virus infection

OBJECTIVE

To search for an association between delivery by vacuum extraction and an increased neonatal risk for herpes simplex virus (HSV) infection.

METHODS

In a cross-sectional, descriptive, controlled study, the study (vacuum extraction) and control (spontaneous delivery) groups each included 50 consecutive women with no history of HSV infection. Cultures for HSV were obtained from the genital tracts of all parturient women and the scalps of their newborns.

RESULTS

Following operative vaginal delivery, two newborns (4%) had scalp vesicles and cultures were positive for HSV for both mothers and newborns; two newborns (4%) had scalp vesicles and cultures were negative for HSV; and two newborns (4%) without scalp vesicles had cultures positive for HSV. Following spontaneous delivery, cultures were positive for HSV for four women and their newborns (8%).

CONCLUSION

Herpes simplex virus isolated from the scalps of newborns may often result from colonization rather than infection.

Herpes simplex virus infection after vacuum-assisted vaginally delivered infants of asymptomatic mothers

OBJECTIVE

To determine whether vacuum extraction technique is associated with an increased risk of herpes simplex virus (HSV) infection in infants born to asymptomatic mothers.

PATIENTS AND METHODS

We reviewed the charts of all infants born at the Edith Wolfson Medical Center and admitted to the hospital's neonatal intensive care unit from January 1999 to June 2002 diagnosed with HSV infection.

RESULTS

During the study period, 6953 infants were delivered at our institution and 11 infants had HSV infection. The prevalence of neonatal HSV infection was 1.6 per 1000 live births. In 699 infants, vacuum extraction was used for delivery. Five out of the 11 infants delivered vaginally by vacuum extraction developed HSV infection at the site of the vacuum extractor application. They were born to mothers who were asymptomatic at delivery and had no history of HSV genital infection. HSV type 2 was isolated from the vesicular fluid in all infected infants delivered by vacuum extraction, and none had central nervous system involvement. The prevalence of neonatal HSV infection in vacuum-assisted births was seven per 1000 live births as compared to 0.95 in 1000 in infants delivered vaginally or by cesarean section (p<0.0001). The relative risk of HSV infection in infants born in vacuum-assisted births was 7.45 (95% confidence interval (CI) 1.99 to 27.42, p=0.001). All patients were treated with intravenous acyclovir and no recurrences of HSV infection have been noticed at follow-up.

CONCLUSIONS

Laceration of the fetal scalp by vacuum extraction technique may enhance the acquisition and the early appearance of cutaneous infection in infants exposed to HSV shedding in the genital tract of asymptomatic mothers, as the virus gains access through the lacerated scalp.

Esophageal pH study and symptomatology of gastroesophageal reflux in newborn infants

A retrospective study was undertaken to assess the association between esophageal pH monitoring variables and signs such as regurgitation, vomiting, apnea, bradycardia, and cyanotic episodes attributable to gastroesophageal reflux (GER) in neonates. One hundred thirty-four infants with one or more of the above-described signs underwent 24-hour distal esophageal pH monitoring in the neonatal intensive care unit, and were divided into 2 groups by gestational age. Group 1 (preterm infant group) consisted of infants aged 25 to 36 weeks of gestation ( n = 45) and group 2 (term infant group) consisted of infants aged 37 to 42 weeks gestation ( n = 89). Esophageal pH monitoring variables were compared by gestational age group and within preterm infants by theophylline treatment and, separately, by nasogastric tube using the Mann-Whitney U test. Comparisons of nominal data were made using the chi square test. Logistic regression analysis was used to assess the net effect of each independent variable on the risk of developing GER. The prevalence of GER was not influenced by gestational age. The prevalence of gastrointestinal signs did not differ between groups. Cardiorespiratory signs attributed to GER were more frequent in preterm infants than in term infants. The number of episodes with pH < 4 in 24 hours was greater in the term compared with the preterm infant groups. Logistic regression analysis failed to detect an association between acid GER and gestational age, apnea, bradycardia, cyanotic episodes, vomiting, or regurgitation. Theophylline treatment and the presence of a nasogastric tube did not significantly affect the esophageal pH monitoring variables in preterm infants. Preterm infants have a smaller number of reflux episodes compared with term infants. In addition, treatment with theophylline for apnea of prematurity and the presence of a nasogastric tube in preterm infants did not significantly affect pH-monitoring variables in preterm infants.

Risk factors for neonatal seizures in very low birthweight infants: population-based survey

The developing brain has an increased susceptibility to seizure activity, and neonatal seizures can adversely affect neurodevelopmental outcome. This study aimed to determine the incidence of neonatal seizures in very low birthweight infants and to identify perinatal and postnatal factors associated with the occurrence of clinical seizures. A population-based cohort of 6525 very low birthweight infants born from 1995 through 1999 comprised the study group. Maternal, perinatal, or postnatal variables that showed a significant association with neonatal seizures in a univariate analysis were tested by a multiple logistic regression to assess the independent effect of each variable on the risk of seizures. The overall incidence of seizures was 5.6%. Significant independent predictors of neonatal seizures were decreasing gestational age, male gender, respiratory distress syndrome, pulmonary air leak (pneumothorax and pulmonary interstitial emphysema), intraventricular hemorrhage, periventricular leukomalacia, patent ductus arteriosus, surgical ligation of patent ductus arteriosus, necrotizing enterocolitis, and surgical treatment of necrotizing enterocolitis. Neonatal seizures appear to be associated with major morbidities and surgical interventions in very low birthweight infants. Continuous electroencephalographic monitoring could be warranted in infants following surgical treatment.

Neonatologists are using much less dexamethasone

Two historical cohorts (1993-1994 and 2001) of preterm infants ventilated for respiratory distress syndrome were compared. Dexamethasone administration fell from 22% to 6%. Chronic lung disease in survivors rose slightly from 13% to 17%, and mortality fell from 21% to 15% (other causes). The effect of restriction of dexamethasone use on chronic lung disease and mortality remains to be seen.

Nitric oxide inhalation and high frequency oscillatory ventilation for hypoxemic respiratory failure in infants

BACKGROUND

High frequency oscillatory ventilation has proved valuable in recruiting and sustaining lung volume; the combined treatment may augment nitric oxide delivery to target vessels. NO therapy lowers pulmonary resistance and improves oxygenation.

OBJECTIVE

To retrospectively review data on changes in oxygenation-indicated by arterial/alveolar PO2 ratio, oxygenation index, and outcome--in a cohort of 10 infants with hypoxemic respiratory failure in whom nitric oxide inhalation was instituted in a compassionate-use protocol after deteriorated oxygenation.

METHODS

NO inhalation was administered at a range of 0.12-122 days of life using the SensorMedics system in 10 infants who developed hypoxemic respiratory failure associated with a variety of lung diseases while on HFOV.

RESULTS

The infants' birthweight was 1,717 +/- 1,167 g and their gestational age 31.1 +/- 6.5 weeks. Mean exposure to NO inhalation was 14.2 days and ranged from 3-59 days. Oxygenation index decreased from 39.3 +/- 13.2 to 12.7 +/- 6.9 (P < 0.0002) after NO therapy. Despite an initial prompt response to NO inhalation, two patients died of progressive intractable respiratory failure and one term infant died of extrapulmonary complications (hypoxic ischemic encephalopathy grade III and multiorgan failure).

CONCLUSION

Our results indicate that the combined treatment of HFOV and NO inhalation is superior to HFOV alone for improving oxygenation in a selected cohort of infants ventilated for a variety of lung diseases.

Survival of a 300-g infant ventilated by high-frequency oscillatory ventilation for respiratory distress syndrome

We report a case of an infant delivered before the completion of 26 wks' gestation, weighing 300 g at birth, and treated with high-frequency oscillatory ventilation for respiratory distress syndrome. Her neurologic examination at 18 months of age is compatible with mild delay in gross and fine motor skills.

Massage therapy by mothers and trained professionals enhances weight gain in preterm infants

BACKGROUND

The method of "massage therapy" has consistently shown increased weight gain in preterm infants. The weight gain was apparent during massages administered by professionals.

AIMS

To replicate the results of increased weight gain in the course of "massage therapy" in preterm infants, and utilize a new, cost-effective application of this method by comparing maternal to nonmaternal administration of the therapy.

STUDY DESIGN

Random cluster design.

SUBJECTS

The study comprised 57 healthy, preterm infants assigned to three groups: two treatment groups--one in which the mothers performed the massage, and the other in which a professional female figure unrelated to the infant administered the treatment. Both these groups were compared to a control group.

RESULTS

Over the 10-day study period, the two treatment groups gained significantly more weight compared to the control group (291.3 and 311.3 vs. 225.5 g, respectively). Calorie intake/kg did not differ between groups.

CONCLUSIONS

Mothers are able to achieve the same effect size as that of trained professionals, allowing cost-effective application of the treatment within the neonatal intensive care unit.

[Survival of a 300 gram infant]

Despite progress in neonatal medicine and the development of new methods of treatment such as surfactant administration and new modalities of ventilation, mortality remains significant among newborn infants weighing less than 500 gram. Neurodevelopmental outcome of infants born before 26 weeks gestation is perceived as very poor. As the result of recent reports, there have been calls for limitation of medical care for these infants. We report of only 4 infants weighing less than 400 grams, who have survived. Two of these infants developed respiratory failure and required aggressive conventional mechanical ventilation. We report on the survival of an infant delivered before the completion of 26 weeks gestation period and weighing 300 grams. The infant was ventilated by high frequency oscillatory ventilation for respiratory distress syndrome. She is the second smallest infant reported in the medical literature.

Variations in neutrophil count in preterm infants with respiratory distress syndrome who subsequently developed chronic lung disease

Neutrophil counts were studied in 62 preterm infants receiving mechanical ventilation for neonatal respiratory distress syndrome (NRDS). Exploratory analysis indicated that the severity of NRDS, as demonstrated by fractional inspired oxygen (FiO2), mean airway pressure (MAP), arterial-alveolar PO2 ratio (a/APO2) and oxygenation index (OI), was correlated with percentage change of neutrophil counts during the first 5 days of life. Further analysis demonstrated that infants with NRDS who subsequently developed chronic lung disease (CLD) (n = 21) had statistically significant differences in variation of neutrophil counts when compared with the remainder (n = 41) without CLD (-35.0% +/- 4.3 vs. -16.9% +/- 5.8, p < 0.02). It is concluded that significant variations in neutrophil counts during the first 5 days of life may be found in infants with NRDS who subsequently develop CLD and that these changes may have predictive value regarding the development of CLD.

Factors affecting plasma bilirubin in preterm infants ventilated for respiratory distress syndrome

OBJECTIVE

To evaluate the contribution of various factors to plasma bilirubin level in preterm infants with a birth weight of < 1500 gm in need of mechanical ventilation for respiratory distress syndrome (RDS) during their first week of life.

METHODOLOGY

A total of 50 very low birth weight (< 1500 gm) preterm infants consecutively admitted to the neonatal intensive care unit were studied. Plasma bilirubin levels were determined every 8 hours for the first week of life. Data relating to daily body weight, daily fluid intake, age at onset of gavage feeds, daily caloric intake, and grade of intraventricular hemorrhage (IVH) were collected. Data relating to mechanical ventilation were collected every 4 hours as follows: fractional inspired O2, arterial PO2, arterial PCO2, and mean airway pressure. An arterial/alveolar PO2 ratio and a corrected oxygenation index were computed for the first 2 days of life. A bilirubin index (BI), defined as the ratio of peak plasma bilirubin level to birth weight1/3, was used to study the association between bilirubin and the above variables. A BI was also used as a criterion for starting and discontinuing phototherapy. Multiple linear regression analysis was used to model BI.

RESULTS

IVH (p < 0.0001), age at onset of gavage feeds (p < 0.003), oxygenation index (p < 0.007), and gestational age (p < 0.05) made a significant contribution to variations in BI (37.16%, 43.71%, 48.99%, and 53.33%, respectively).

CONCLUSION

Hyperbilirubinemia in ventilated preterm infants with RDS is most likely multifactorial; entities quite distinct from RDS (such as nutrition and IVH) may significantly contribute to its variation.

A prospective search for urinary tract abnormalities in infants with isolated preauricular tags

OBJECTIVE

To determine whether isolated preauricular tags are associated with urinary tract abnormalities.

METHODOLOGY

Seventy consecutive infants with isolated preauricular tags were examined by ultrasonography for urinary tract abnormalities on day 3 or 4 of life between January 1993 and August 1999, after parental consent and ethics approval. Karyotype analysis was conducted in all infants with urinary tract abnormalities. The study group was compared with a control group of 69 infants without preauricular tags hospitalized during the same period. The control group consisted of infants who underwent urinary tract ultrasonography as part of an investigation for persistent regurgitation and/or vomiting associated with cyanotic spells.

RESULTS

Urinary tract abnormalities were detected in 6 infants with isolated preauricular tags (6/70; 8.6%). Types of anomalies were as follows: hydronephrosis in 5 cases and horseshoe kidney in 1 case. The causes of hydronephrosis were ureteropelvic junction obstruction in 3 cases and vescicoureteric reflux in 2 cases. None of the infants in the control group had such abnormalities. All infants with urinary tract abnormalities had normal chromosomes. No statistically significant differences existed between groups concerning birth weight, gestational age, intrauterine growth, and male-to-female ratio.

CONCLUSIONS

This study suggests a significant prevalence of urinary tract abnormalities in infants with preauricular tags. We recommend, therefore, that urinary tract ultrasonography be conducted in the routine assessment of infants with isolated preauricular tags.

Intrauterine growth retardation and brainstem auditory-evoked response in preterm infants

Intrauterine growth retardation is frequently associated with intrauterine undernutrition, and can deleteriously affect brain function. Twenty-eight premature small for gestational age infants were compared with 28 premature appropriate for gestational age infants to determine whether intrauterine growth retardation was associated with abnormalities in the auditory pathway in the early neonatal period. The auditory pathway was studied between 4-18 wk of life by analysis of brainstem auditory-evoked potentials elicited by a 10/s 75 decibel above normal adult hearing level (dB nHL) click stimulus presented at the infants' ears. Peak latencies of components I, III and V, and interpeak latencies I-III, III-V and I-V, yielded no statistically significant differences between groups. The present study indicates that intrauterine growth-retarded premature infants may not have abnormalities of brainstem auditory-evoked response in the early neonatal period.

Intrauterine growth retardation and brainstem auditory-evoked response in preterm infants

Intrauterine growth retardation is frequently associated with intrauterine undernutrition, and can deleteriously affect brain function. Twenty-eight premature small for gestational age infants were compared with 28 premature appropriate for gestational age infants to determine whether intrauterine growth retardation was associated with abnormalities in the auditory pathway in the early neonatal period. The auditory pathway was studied between 4-18 wk of life by analysis of brainstem auditory-evoked potentials elicited by a 10/s 75 decibel above normal adult hearing level (dB nHL) click stimulus presented at the infants' ears. Peak latencies of components I, III and V, and interpeak latencies I-III, III-V and I-V, yielded no statistically significant differences between groups. The present study indicates that intrauterine growth-retarded premature infants may not have abnormalities of brainstem auditory-evoked response in the early neonatal period.

Brainstem auditory evoked response in newborns and infants

Brainstem auditory evoked response studies were carried out on 105 neonates, with gestational ages ranging from 26 to 43 weeks. The mean chronologic and postconception ages of the subjects were 6.5 weeks and 40.6 weeks, respectively. Statistically significant relationships between brainstem auditory evoked response and gestational age, postconception age (gestational age plus chronologic age), and the 5-minute Apgar score, were demonstrated. Shortening of brainstem auditory evoked response as related to postconception age was demonstrated and this trend was statistically significant. However, of these factors a statistically significant shortening (maturation) of evoked response was demonstrated only in relation to postconception age.

Failure of early postnatal dexamethasone to prevent chronic lung disease in infants with respiratory distress syndrome

OBJECTIVE

To study the effect of early postnatal dexamethasone (days 1-3) on the incidence and severity of chronic lung disease in preterm infants with respiratory distress syndrome.

METHODS

A multicentre, randomised, placebo controlled, blinded study was carried out in 18 neonatal intensive care units in Israel. The primary outcome measure was survival to discharge without requirement for supplemental oxygen therapy beyond 28 days of life. The secondary outcome measures were requirement for mechanical ventilation at 3 and 7 days, duration of ventilation or oxygen therapy, need for subsequent steroids for established chronic lung disease and incidence of major morbidities.

RESULTS

The study consisted of 248 infants (dexamethasone n = 132; placebo n = 116). No differences were found in the outcome variables except for a reduction in requirement for mechanical ventilation at age 3 days in treated infants (dexamethasone 44%, placebo 67%; P = 0.001). Gastrointestinal haemorrhage, hypertension, and hyperglycaemia were more common in treated infants, but no life threatening complications, such as gastrointestinal perforation, were encountered.

CONCLUSIONS

These data do no support the routine use of early postnatal steroids, but may justify further study in a selected, high risk group of infants.

Autologous umbilical cord blood transfusion

The purpose of this study was to examine some aspects of umbilical cord blood collection for autologous transfusion in premature infants. All 120 microbacterial cultures (aerobic and anaerobic) of cord blood samples as well as 30 cultures of mycoplasma were treated. Cord prothrombin fragment (F 1 + 2) concentrations were quantified at one and 10 minutes after clamping of the cord. F 1 + 2 concentrations assessed on 25 newborn infants were similar and no linear association with time of clamping could be drawn. This means that cord blood thrombosis is not activated for at least 10 minutes following clamping of the cord. As far as is known, the first newborn infant to benefit from this method of transfusion is reported here. The premature infant received two portions of autologous blood (on days 5 and 7). No untoward effects were noted. Blood, collected from the umbilical cord, is a safe source for autotransfusion, provided that bacteriological testing has been carried out.

Transient neonatal hypothyroxinemia and the auditory brainstem evoked response

Ten premature infants with low serum thyroxine levels (less than 84 nmol/L) were compared with 10 biochemically euthyroid infants to determine whether hypothyroxinemia in such infants can lead to alterations in the auditory pathway. The auditory pathway was studied between 6 and 11 wk of life by analyzing brainstem evoked potentials elicited by a 10/s, 75 dB above normal adult hearing level click stimulus presented at the infant's ears. Peak latencies of components I, III, and V and interpeak latencies I-III, III-V, and I-V did not yield statistically significant differences between groups. The present study indicates that untreated neonatal hypothyroxinemia does not lead to abnormalities of auditory brainstem evoked response.

Predictive inability of cord zinc, magnesium and copper levels on the development of benign hyperbilirubinemia in the newborn

Cord serum concentrations of zinc, magnesium and copper were determined in 90 healthy term infants. The infants were divided by peak bilirubin values into an icteric group (peak bilirubin > 136 mumol/l) (n = 21) and a control group (peak bilirubin < or = 136 mumol/) (n = 69). Mean cord serum zinc, magnesium and copper concentrations in the icteric group did not differ from those of the control group. Furthermore, no significant correlation was found between peak serum bilirubin concentrations and cord serum concentrations of these three elements. We conclude that cord serum concentrations of zinc, magnesium or copper are not useful in predicting which neonates will develop hyperbilirubinemia.

Umbilical ascorbic acid levels in fetal distress

Umbilical arterial and venous blood samples were obtained at birth immediately after clamping the cord in 38 infants. Simultaneously, maternal arterial samples were collected. Arterial blood samples were analyzed for acid-base blood gas content and venous blood samples were analyzed for plasma ascorbic acid levels. The umbilical plasma ascorbic acid level was significantly higher when compared with maternal plasma levels (172.9 +/- 39.2 vs. 57.8 +/- 21.0 mumol/liter, p < 0.0001). Correlations between maternal ascorbic acid levels and umbilical cord levels proved to be insignificant. Umbilical ascorbic acid levels in the 2 groups of infants characterized by the presence or absence of fetal distress showed significantly higher levels in the fetal distressed group (17 infants) when compared to the non-distressed group (21 infants)--191.9 +/- 36.0 vs. 157.4 +/- 34.6 mumol/liter, p < 0.005. The use of an umbilical cord ascorbic acid cut-off point of 95.8 mumol/liter gave a sensitivity of 76% and a specificity of 67% as predictors for the presence or absence of fetal distress (p < 0.025). The results of the present study demonstrate a substantial increase in ascorbic acid levels in infants exposed to intrapartum fetal distress, without any clinical sign of such insult at or after birth.

Onset of spontaneous labor and changes in E2 and progesterone levels--possible interrelation

Unlike the findings in animal studies, in which a decline in progesterone levels is clearly associated with the onset of labor, investigation of progesterone levels among human parturients has resulted in controversy. This study was designed to address the issue and evaluate labor-onset related changes of estradiol-progesterone (E2-P) concentration in fetal scalp serum, umbilical vein serum and in the peripheral maternal serum. Seven women in spontaneous labor, were compared to 7 women in whom labor was induced. Our results reveal a significant decrease in the maternal serum P concentration when spontaneous labor is taking place (120.6 +/- 24.5 mg/ml verus 177.3 +/- 61.4 mg/ml, p < 0.05). Significant change in the ratio of the fetal scalp to the maternal serum E2/P ratio in women at spontaneous labor versus induced labor is also shown. We could not demonstrate any changes in the E2 levels in relation to labor. We conclude that the onset of labor in human pregnancy is most probably preceded by local changes in the levels of P and ratio of P to E2. These changes may play an important regulatory role in onset of labor.

Preincubation with intravenous lipid emulsion reduces chemotactic motility of neutrophils in cord blood

Neutrophils from cord blood of healthy term infants were isolated and incubated for 30 min with varying concentrations of intravenous lipid emulsion (ILE) solution (4, 8, 20 mg/ml). In vitro assay of chemotaxis was performed after incubation for 120 min with endotoxin-activated serum (EAS). Neutrophil random motility was unchanged after ILE incubation yet chemotactic factor (EAS)-stimulated motility was significantly reduced in a dose-related pattern.

Effect of gentamicin on the auditory brainstem evoked response in term infants: a preliminary report

Seven essentially healthy term infants who received gentamicin starting on the 1st day of life for prolonged rupture of membranes and maternal fever were compared with nine healthy term infants to determine whether this drug induces alterations in the auditory pathway. The auditory pathway was studied on the 3rd day of life by analyzing brainstem auditory evoked potentials elicited by a click stimulus presented at the infant's ears. Latencies of components III and V, interval I-III, and interval I-V were significantly prolonged in the gentamicin group, indicating impairment of the central component of the auditory pathway. Peak and trough serum gentamicin levels all fell within the recommended therapeutic range. The study indicates that short course gentamicin therapy in healthy newborn infants can lead to abnormality of auditory function.

Reduced platelet counts in neonatal respiratory distress syndrome

Platelet counts were studied in preterm infants with the respiratory distress syndrome (RDS), excluding patients with significant perinatal and postnatal hypoxia. Counts fell to a nadir on day 4 (p less than 0.000). Exploratory analysis indicated that severity of RDS (levels of FiO2 and mean airway pressure), airleak syndrome, grade of intraventricular hemorrhage (IVH) and low platelet count on day 1 were correlated with low platelet count on days 4 and 5. Further analysis by stepwise removal of each variable demonstrated statistically that FiO2 exerted a unique influence on the change in platelet count between day 1 and days 4/5 (p less than 0.002). It is concluded that the severity of RDS is strongly associated with the fall in platelet count in the first few postnatal days. The effect of IVH on platelet count may be secondary to the effect of the RDS.

Platelet counts in maternal and umbilical venous blood at the time of delivery

Platelet count in 38 paired maternal venous and umbilical venous specimens were determined at delivery. Umbilical values were significantly higher than simultaneous maternal values (p = 0.004), and a significant relationship was demonstrated between umbilical values and maternal values (r = 0.54, p = 0.0004). Associations between platelet counts and acid-base variables were found to be insignificant in the mother and the umbilical cord.

High-frequency oscillation in the rescue of infants with persistent pulmonary hypertension

High-frequency oscillatory ventilation (HFOV) was used to treat 41 infants with persistent pulmonary hypertension of the newborn (PPHN). Of the 37 patients who showed early improvement on HFOV, three died. The remaining 34 patients demonstrated, within one hour of the switchover to HFOV, a rise in mean arterial/alveolar oxygen tension ratio (PaO2/PaO2) from 0.093 +/- 0.041 (SD) to 0.132 +/- 0.051 (p less than .001), and a fall in mean PaCO2 from 42 +/- 10 to 34 +/- torr 9 (p less than .01). Mean airway pressure (Paw) fell significantly (p less than .01) within 12 h. The mean duration of conventional mechanical ventilation before starting HFOV was longer in 13 patients who developed bronchopulmonary dysplasia (BPD) than in 21 non-BPD patients (44.7 +/- 32.3 vs. 19.1 +/- 15.6 h, p less than .002), as was the duration of exposure to Paw greater than 15 cm H2O during that treatment mode (31.8 +/- 21.3 vs. 9.5 +/- 6.0 h, p less than .001). HFOV is often effective in the treatment of patients with PPHN, and early initiation of this type of mechanical ventilation may be associated with a reduced incidence of BPD.

Reduction of platelet counts induced by mechanical ventilation in newborn infants

The association between platelet counts and mechanical ventilation was assessed in 61 newborn infants with respiratory distress syndrome, 10 infants with congenital diaphragmatic hernia, and 10 infants with tracheoesophageal fistula. A significant decrease in platelet counts was observed during mechanical ventilation: (mean +/- SD) reduction of 39% +/- 5%, 42% +/- 5.6%, and 11.9% +/- 5.4% in the three groups, respectively, independent of other causes. In the group with congenital diaphragmatic hernia, there was a significant correlation between mean airway pressure and the reduction in platelet counts. In a subsequent series of experiments, platelet counts were recorded before and during ventilation in rabbits. A significant mean decrease of 37.3% in platelet counts was associated with ventilation with either air or pure oxygen. Results of these studies indicate that mechanical ventilation itself may cause a major decrease in platelet count in newborn infants.