Oscar G. Casiro

Deficits in the processing of local and global motion in very low birthweight children

This study evaluated the impact of premature birth on the development of local and global motion processing in a group of very low birthweight (<1500 g), 5- to 8-year-old children. Sensitivity to first- and second-order local motion stimuli and coherence thresholds for global motion in random dot kinematograms were measured. Relative to full-term controls, premature children showed deficits on all three aspects of motion processing. These problems could not be accounted for by stereo deficits, amblyopia, or attentional problems. A history of mild retinopathy of prematurity and/or intraventricular hemorrhage increased risk, but deficits were observed in some children with no apparent ocular or cerebral pathology. It is important to note that, despite the observed group differences, individual profiles of performance did vary; the results suggest that these three forms of motion processing may involve separate neural mechanisms. These findings serve to increase our understanding of the organization and functional development of motion-processing subsystems in humans, and of the impact of prematurity and associated complications on visual development.

Alveolar capillary dysplasia. Report of a case of prolonged life without extracorporeal membrane oxygenation (ECMO) and review of the literature

We describe an unusual infant with the diagnosis of alveolar capillary dysplasia who had a relatively prolonged life without extracorporeal membrane oxygenation (ECMO). We have used this case as a springboard for a thorough review of the literature. This was a full-term female infant who presented with a picture of persistent pulmonary hypertension of the newborn. She was treated as such, with various ventilatory modes, alkalinizing agents, surfactant therapy, tolazoline, prostacyclin and nitric oxide. Because of the prolonged clinical course the possibility of alveolar capillary dysplasia was raised. The parents refused ECMO. Despite all efforts she progressively deteriorated and died at 22 days of age. Macro- and microscopic examination of the lung at autopsy were diagnostic of alveolar capillary dysplasia. A detailed review of 39 cases published in the literature with comments regarding incidence, etiology, pathophysiology, clinical picture, diagnosis and treatment is presented.

Language development of very low birth weight infants and fullterm controls at 12 months of age

Twenty-eight very low birth weight (VLBW) and 32 full term infants were prospectively assessed at one year of age for hearing, language development and neurological status. The prevalence of conductive hearing deficits was the same in both groups. Language scores in VLBW infants were significantly lower than in fullterm controls and 39% had significant language delays. VLBW infants exhibited a shorter attention span and were less likely to understand simple questions, to recognize objects or body parts when named, to initiate speech-gesture games, to follow simple commands and to imitate or use words consistently. Language quotients were directly associated with gestational age and five minute Apgar scores and inversely associated with severity of intraventricular hemorrhage, bronchopulmonary dysplasia and length of hospital stay. VLBW small for gestational age infants exhibited more advanced language skills than VLBW appropriate for gestational age infants. Language delays were more prevalent among, but not limited to, infants with mild to moderate neurological abnormalities. The influence of prematurity and VLBW on language development is complex and multifactorial and research is continuing to determine the predictive validity and long term significance of the early language delays described in this study.

One-year follow-up of 89 infants with birth weights of 500 to 749 grams and respiratory distress syndrome randomized to two rescue doses of synthetic surfactant or air placebo☆☆☆★

Abstract Double-blind neurodevelopmental and physical evaluations were conducted at 1-year adjusted age in 89 infants with birth weights of 500 to 749 gm who had respiratory distress syndrome in the neonatal period and were randomized to receive two rescue doses of a synthetic surfactant (Exosurf Neonatal, Burroughs Wellcome Co., Research Triangle Park, N.C.) or air placebo. The trial used a common protocol and was conducted at 13 hospitals; patients were entered in the trial between February 1988 and September 1990. Ninety-five percent of surviving infants were assessed. Growth and development in the two groups were equivalent. Mean Bayley Scales of Infant Development scores were comparable (mental development index, 79 ± 22 vs 87 ± 20; psychomotor development index, 73 ± 18 vs 81 ± 19 for air placebo and synthetic surfactant, respectively). The incidence of severe retinopathy of prematurity was significantly decreased in the surfactant group compared with the air placebo group (15% vs 34%; relative risk 0.428; 95% confidence interval 0.2 to 0.9). Overall, administration of surfactant appeared to increase the probability of a favorable outcome. Confirmation of the trends observed in this study would provide a strong rationale for the rescue use of synthetic surfactant in extremely low birth weight infants with respiratory distress syndrome even if overall mortality is not reduced. (J P EDIATR 1995;126:S53-60)

One-year outcome in 232 premature infants with birth weights of 750 to 1249 grams and respiratory distress syndrome randomized to rescue treatment with two doses of synthetic surfactant or air placebo

A randomized, double-blind, placebo-controlled trial was performed in 13 hospitals in Canada to assess whether two rescue doses of a synthetic surfactant (Exosurf Neonatal) would reduce mortality and morbidity rates in neonates with respiratory distress syndrome who weighed from 750 to 1249 gm. As part of the original trial design, double-blind follow-up evaluations were performed at 1-year adjusted age. A total of 118 patients who received air placebo and 114 patients who received synthetic surfactant were evaluated at 1 year. Growth and development in the two groups were equivalent. Scores on the Bayley Scales of Infant Development were within the normal range for both groups (mental development index, 90 +/- 22 vs 92 +/- 22; psychomotor development index, 81 +/- 19 vs 87 +/- 22 for the air placebo and synthetic surfactant groups, respectively). However, in both groups the proportion of infants with any impairment (air placebo group, 43 of 118 (36%); synthetic surfactant group, 41 of 114 (36%) and severe impairment (air placebo group, 29 of 118 (25%); synthetic surfactant group, 21 of 114 (18%)) was substantial. We conclude that two rescue doses of synthetic surfactant in infants with RDS who weighed 750 to 1249 gm had no detrimental effect on developmental outcome or late morbidity. No long-term benefits to 12-months corrected age were observed with the use of surfactant in this weight class. Larger studies or meta-analyses of existing trials will be required to determine if there are any late outcome advantages associated with rescue use of synthetic surfactant in infants weighing 700 to 1249 gm.

The natural history and predictive value of early language delays in very low birth weight infants.

A cohort of 28 VLBW (less than or equal to 1500 g) infants was assessed at 1 and 3 years of age for hearing, language development and neurological status. Language delays were detected in 11 (39%) infants at 1 year, and in four (15%) at follow up at 3 years of age (P less than 0.05). Language quotients were significantly associated with perinatal variables at 1 but not at 3 years of age. Infants with neurological abnormalities had significantly lower language quotients at the 3-year follow up. No child with a normal language profile at 1 year exhibited a delay at 3 years of age.

Outcome of Very-Low-Birth-Weight (<1,500 Grams) Infants Born to Mothers with Diabetes

Premature delivery is common in pregnancies complicated by maternal diabetes. However, the outcome of very-low-birth-weight infants (VLBWI) born to mothers with diabetes is not known. Employing a matched double-cohort design, we investigated the influence of maternal diabetes on the outcome of VLBWI born in Winnipeg from 1988 to 1994. We compared mortality rates and early and late morbidity rates in VLBWI born to mothers with diabetes mellitus (DM) (cases, n=43, 23 with gestational DM and 20 with pregestational DM) and without DM (controls, n=539). Controls were matched for gestational age (GA), sex, and the year of birth. All subjects were enrolled in the Newborn Follow-Up Program. Relative risks and 95% confidence limits were calculated for each variable and Chi2 analysis, Student t-test, and Mann-Whitney test were used as appropriate for analysis. Diabetes mellitus control was assessed by conventional criteria. There were no differences between cases and controls in mode of delivery, birth weight (mean SD, 1,160±25 g vs 1,110±26 g), GA (29±2.8 wk vs 29±2.4 wk), smallness for gestational age (35% vs 30%), head circumference (26.5±1.9 vs 26.2±2.2 cm), length (38.8±2.8 vs 37.5±3.7 cm), Apgar score <4 at 1 min (42% vs 40%) and <7 at 5 min (37% vs 42%). Incidence of hyaline membrane disease (60% vs 71%), bronchopulmonary dysplasia (33% vs 31%), patent ductus arteriosus (30% vs 43%), necrotizing enterocolitis (12% vs 12%), sepsis (23% vs 25%), acute renal failure (9% vs 10%), intraventricular hemorrhage-all grades (74% vs 64%), retinopathy of prematurity-all stages (30% vs 26%), median days on ventilator (4 vs 4 days), and median days on supplemental oxygen (46 vs 42 days) were similar in both groups (p=NS, 95% confidence limits included 1 for all of these variables). There was no significant difference in mortality (21% vs 15%) or the incidence of major congenital anomalies. Weight, head circumference, and length at 6,12, and 18 months were similar in both groups. There were no group differences in developmental quotients, prevalence of neurodevelopmental impairments, respiratory morbidity, or number of hospitalizations up to the last follow-up (18 months). Our data suggest that with contemporary perinatal care there is no significant increase in mortality rates or early and late morbidity rates between VLBWI born to mothers with DM and VLBWI of nondiabetic mothers. It seems that with reasonable diabetic control, prematurity rather than the diabetic state determines the neonatal outcome, and this knowledge can be useful in parental counselling.

Subarachnoid fluid collections: A cause of macrocrania in preterm infants

We report the outcome of 12 very low birth weight infants with macrocrania caused by subarachnoid fluid collections. By the age of 15 to 18 months, head growth had stabilized along a curve above and parallel to the 95th percentile. No infant required neurosurgical intervention, nor was cerebral palsy or mental retardation diagnosed in any of the infants.

Neurodevelopmental outcome of infants exposed to indomethacin antenatally

The use of indomethacin as a tocolytic agent has been limited because of potential fetal and neonatal complications. We investigated the neonatal and neurodevelopmental outcome of preterm infants exposed antenatally to this drug. The records of 779 women admitted in premature labor during a five year period were reviewed. Nineteen women who received indomethacin (initial dose of 50-100 mg followed by 50-100 mg/day) and their 25 infants were identified. Delivery was delayed for a week or longer in 86.6% of the mothers. There were two deaths: a stillborn with multiple congenital anomalies and a neonate with congenital listeriosis. Seven infants were born at term without complications. Fifteen infants born prematurely were compared to 15 control infants not exposed to indomethacin antenatally. There were no statistically significant differences between the two groups in the prevalence or severity of thrombocytopenia, hyperbilirubinemia, intraventricular hemorrhages, patent ductus arteriosus, persistent pulmonary hypertension, bronchopulmonary dysplasia, and necrotizing enterocolitis. Mean BUN, creatine, and urine output for the first three days of life were similar in the two groups. No differences were found at the 6-12 month neurodevelopment assessment. We found no neonatal complications attributable to the antenatal use of indomethacin.

Neurodevelopmental outcome of very low birth weight children requiring chest compressions immediately after birth. |[dagger]| 1160

There is a small body of literature documenting the outcome of premature infants surviving neonatal resuscitation much of which is pessimistic. We investigated the outcome of very low birth weight infants who had chest compressions (CC) in the delivery room compared to infants of similar characteristics who did not require that level of initial intervention. Methods: A search of the computerised Newborn Follow Up database identified all infants meeting the following criteria: born at the Health Sciences Centre in 1992-94, birth weight < 1250g; no evidence of congenital anomalies or maternal substance abuse likely to affect neurodevelopmental outcome; a minimum of 12 months follow up. Chest compressions were initiated following established guidelines for neonatal resuscitation. The study group consisted of survivors of CC in the delivery room. The control group consisted of all other infants meeting the above criteria. The data base contains antenatal and perinatal data extracted from the hospital chart and follow up data collected prospectively. Results: Of the 163 infants born weighing <1250g in the study time period 36(22%) required CC in the delivery room. Mortality for this group was higher(53% vs 24%, p<0.001). The 17 survivors in the CC group were compared to 63 survivors in the non CC group who met the inclusion criteria. There were no differences in birth weight (881±179g vs 962 ±186g) or days of mechanical ventilation(21±13 vs 15 ±22) between the two groups although the CC group was born at a more premature gestation (27.2±1.6 vs 28.1±2.5, p< 0.04) and stayed longer in hospital (99±25 vs 80±39, p<0.01). There were no significant differences in the rates or severity of intraventricular hemorrhage, seizures, hearing loss or clinical diagnosis of cerebral palsy between the two groups. The CC group had a significant increase in retinopathy of prematurity of grade 3 or 4 (37% vs 17%, p<0.03). The gross motor, fine motor, adaptive and language developmental quotients as assessed using the Gessel Scales showed no significant differences between the two groups. Conclusion: In contrast to previous literature our data suggest that infants that require cardiac compressions at birth, although having a higher mortality have a comparable neurodevelopmental outcome to those that do not.