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Query: UMLS:C0728731 (prematurity)
 7,134 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Retinopathy of prematurity (ROP) is a major problem in both highly developed countries and countries with emerging technology. The incidence of ROP has been stable over the last 2 decades despite improvements in neonatology. Threshold ROP occurs in about 5% of premature infants in the US with birthweights <1.25kg. Despite treatment, a sizable minority will become blind (up to 20 to 30%). The pathophysiology of ROP can be separated into 2 phases. Phase I is hyperoxia-vasocessation. Phase II is hypoxia-vasoproliferation. The former occurs immediately following premature birth. The provision of supplemental oxygen causes retinal hyperoxia, a down regulation of vascular endothelial growth factor (VEGF) and a consequent cessation of normal retinal vascularisation. Systemic factors and increasing retinal metabolic demands cause a shift to phase II when a relative retinal hypoxia develops. This hypoxia stimulates VEGF production, leading to renewed vascularisation. This can be the resumption of normal vascularisation or abnormal neovascularisation, depending on local retinal responses. The management of ROP begins with a reliable evidence-based screening protocol. All interested parties must cooperate in developing and implementing foolproof screening protocols. Hospital officials, nursery personnel, neonatologists and ophthalmologists all have areas of responsibility in ensuring adequate screening. ROP management involves prevention, interdiction and correction. Prevention includes: adequate prenatal care which minimises premature birth, and appropriate systemic intensive care which lessens the tissue hyperoxia/hypoxia swings. Pharmacological vitamin E supplementation has largely been abandoned and ambient light reduction has been shown to be ineffective. The value of inositol supplementation and angiogenesis inhibitors in preventing ROP is presently under investigation. Interdiction concentrates on ablation of the peripheral avascular retina, thus dramatically decreasing VEGF production. Both cryotherapy and laser photocoagulation are effective; however, unfortunately, poor outcomes persist despite treatment. Supplemental oxygen administration has so far proven ineffective in limiting ROP progression. Finally, correction focuses on vitrectomy/retinal detachment repair. While anatomically successful, this procedure is often unsuccessful in terms of restoration of vision (<5% success rate). In conclusion, despite improvements in neonatology, ROP, potentially leading to blindness, continues to be a common problem associated with prematurity. Future management success must concentrate on discovering new modes of treatment, especially prevention.
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PMID:The management of retinopathy of prematurity. 1135 98

The study analyses the incidence of the retinopathy of prematurity (ROP) and its correlation with the most important risk factors in neonates with gestational age (GE) < or = 32 weeks and/or with birth weight (BW) < or = 1500 g. The cohort of our study is composed by 305 preterms with Mean GE of 29.8 weeks and Mean BW of 1312 g, studied at the Neonatal Intensive Care Unit of the University of Parma during January 1993-December 1999. The incidence of ROP resulted 19.7% in our group and was inversely proportional to the GE and BW. No preterms with GE < or = 32 weeks presented retinopathy, while there has been an incidence of the 65% in the subjects with GE lower than 26 weeks. The most severe grade of ROP was mainly seen in the newborns with the lowest GE (31%), whilst only the 1.5% of the preterms with GE of 30-31 weeks developed ROP of stage 3 or 3+. Similar results were seen when the data were compared with the birth weight. However a direct relation was seen with the duration of the O2 therapy and with the typical pathologies of the prematurity, namely respiratory distress syndrome (RDS) and intraventricular haemorrhages (IVH). Among the other risk factors evaluated, the blood transfusion was the most relevant.
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PMID:[Retinopathy of prematurity: incidence and risk factors]. 1142 16

To find out whether the cryotherapy for the treatment of the retinopathy of prematurity (ROP) causes structural changes of the extraocular muscle (EOM), and also whether the changes are related with the occurrence of strabismus. To examine the acute stage change, we conducted a transconjunctival cryotherapy around the superior rectus muscle of a rabbit and resected it 0, 3, 7, 14, and 28 days after the cryotherapy. In observing chronic changes, we first categorized patients who had an esotropia surgery into groups, one of which combined prematurity and cryotherapy and one group affected by prematurity but without having had cryotherapy. Then we compared the change of EOM with that of a fullterm infant group. In a rabbit, edema, acute inflammatory cells and a large amount of degenerated muscle fibers were observed immediately after the cryotherapy and on the 3rd day. On the 7th day, regenerated muscle fibers were observed and on the 14th day, the inflammatory cells decreased and the amount of regenerated muscle fiber increased. On the 28th day, abnormal findings were not observed any more and the muscle was found to be normal. When chronic changes of EOM in human on 1 1/2 to 8 1/2 years after cryotherapy, there were no abnormal findings observed in three groups. From the study, we can infer that cryotherapy can cause acute inflammation and necrosis of muscle fiber but such an acute change will improve and does not result in structural change in the long term. Therefore, the occurrence of strabismus in patients with ROP is considered to be attributable to reasons other than injury of EOM.
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PMID:Extraocular muscle changes after cryotherapy for retinopathy of prematurity and the development of strabismus in premature infants. 1181 88

With improving survival of very low birth infants in India, Retinopathy of Prematurity (ROP is likely to emerge as a significant problem. The most important risk factor in the pathogenesis of ROP is prematurity. Other factors like frequent blood transfusions; sepsis, apnea and problems with oxygenation have also been implicated in the causation of ROP. Essentially asymptomatic in the initial stages, a good screening program is essential for the early detection and treatment of this condition. Description of the various stages and threshold ROP has been included in the protocol. Guidelines regarding the procedure of dilatation, ophthalmic examination and treatment (if required) has been provided in the protocols. Close cooperation between the ophthalmologist and neonatologist is essential for a successful program.
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PMID:Retinopathy of prematurity. 1187 27

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 Chi 2 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.
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PMID:Outcome of very-low-birth-weight (< 1,500 grams) infants born to mothers with diabetes. 1236 10

The personal author's experiences has been presented, with regards to the early discovering and adequate preventing of ophthalmology diseases at prematurely born children. Thanks to the development of perinatology, almost every organ can be monitored and functionally examined even before the child is born. Despite all problems, the work of ophthalmo-paediatritians is extremely challenging, because that is the only situation in which embryology of the eye can be seen "In Vitro" and in which the physiological development of the eye's function can been monitored. During the period from 1999 to 2002, it was examined 66 children in total, who had an anamnestical data about prematurity, as well as the data about delivery-weight. Out of these 66 children, there were 40 (60.6%) boys and 26 (39.4%) girls, with 1-4 of age. All children were examined by usual, in daily work available, examination methods. The biggest percentage of children (80%) were sent to us by the paediatritian-neonathologist, and 20% war sent from the Primary Health Care centers, or they were sent from other centers. At 52 (78.7%) of children, the certain changes on the eyes were found, while at 10 (15.1%) children no changes at all were found. At 4 (6.2%) cases, we found minor changes, but we monitored those children as well. Ophthalmology changes were found in almost all forms, from the most complicated (ROP, coloboma horioretinae, congenital glaucoma, congenital cataract), to the simpler ones on which are less difficult to treat (refraction changes, amblyopia, strabismus, ptosis etc). Since these changes are still present with prematuruses, it is necessary to intensively monitor this population, as a part of the multidisciplinary team, made of the experts of the different profiles (paediatritian-neonatologist, otologist, logopedist, ophthalmologist, etc), and which would be possible through the Register of Prematurity. Author introduces her own experience of ophthalmologic diseases in children who are categorized as "risky". A team of different specialists does treatment.
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PMID:[Pathologic ophthalmologic changes in prematurity]. 1276 53

The risk of central nervous, visual, and auditory damage increases from 2/1000 live births in the normal birthweight to > 200/1000 as birthweight falls below 1500 g. Such babies are most likely to be born preterm. Advances in infant care have led to increasing numbers of very-low-birthweight, preterm infants surviving to school age with moderate to severe brain damage. Steroids are one of the current treatments, but they cause significant, long-term problems. The evidence reported here suggests an additional approach to protecting the very preterm infant by supporting neurovascular membrane integrity. The complications of preterm, very-low-birthweight babies include bronchopulmonary dysplasia, retinopathy of prematurity, intraventricular hemorrhage, periventricular leukomalacia, and necrotizing enterocolitis, all of which have a vascular component. Arachidonic acid (AA) and DHA are essential, structural, and functional constituents of cell membranes. They are especially required for the growth and function of the brain and vascular systems, which are the primary biofocus of human fetal growth. Molecular dynamics and experimental evidence suggest that DHA could be the ligand for the retinoid X receptor (RXR) in neural tissue. RXR activation is an obligatory step in signaling to the nucleus and in the regulation of gene expression. Very preterm babies are born with minimal fat stores and suboptimal circulating levels of these nutrients. Postnatally, they lose the biomagnification of the proportions of AA and DHA by the placenta for the fetus. No current nutritional management repairs these deficits. The placental biomagnification profile highlights AA rather than DHA. The resultant fetal FA profile closely resembles that of the vascular endothelium and not the brain. Without this nourishment, cell membrane abnormalities would be predicted. We present a scientific rationale for a common pathogenic process in the complications of prematurity.
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PMID:The potential role for arachidonic and docosahexaenoic acids in protection against some central nervous system injuries in preterm infants. 1284 75

To get a comprehensive picture of prematurity and neonatal death or survival, all factors on the maternal and fetal records that might be pertinent were recorded. This information, having to do with factors such as age, gravida of the mother, blood group incompatibility, period of gestation, weight at birth, type of delivery, medication and anesthesia administered to the mother, is presented in tabular form. In the study of perinatal mortality it was noted that failure to establish normal pulmonary ventilation is the most common cause of death in the neonatal period. Maternal history of relative infertility, that is, previous abortions, stillbirths and premature deliveries, was the most impressive finding in the stillborn series. In the follow-up study of premature infants who survived the neonatal period, 8.5 per cent were found to be severely handicapped. In four cases the handicap was due to congenital anomalies, in two others probably to infection, leaving 12 with complications possibly ascribable to prematurity. Six of these had retrolental fibroplasia as a major handicap. In seven, mental retardation was the presenting problem. Most of the handicapped children had multiple handicaps, which included spasticity, delayed motor development, strabismus, etc. The incidence of the necessity for corrective measures for feet and legs appeared relatively high. In general, survivors compared favorably with the rest of the childhood population. Complications and twinning were associated inordinately often.
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PMID:A five-year study of prematurity. 1330 92

In the cell, reducing and oxidizing molecules modulate the redox state. In embryonic and fetal growth, increased oxidative stress may be detrimental, but an oxidized state can also be beneficial. This is because redox may also affect key transcription factors that can alter gene expression during development. In addition, redox may impact on placentation and amniotic membrane integrity during pregnancy. Lastly, diseases of prematurity, such as necrotizing enterocolitis, retinopathy of prematurity, and chronic lung disease, may be modulated by redox in the premature. Because antioxidant therapies have not necessarily modified the outcome of these diseases, some debate exists as to this. Nonetheless, sufficient evidence suggests a role for redox throughout embryonic, fetal, and postnatal development. This evidence will be explored here.
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PMID:Role of redox in fetal development and neonatal diseases. 1471 46

Early neonatal intensive care unit (NICU) discharge has been advocated for selected preterm infants to reduce both the adverse environment of prolonged hospital stay and to encourage earlier parental involvement by empowering parents to contribute to the ongoing care of their infant, and thereby reducing costs of care. Randomized trials and descriptive experiences of early discharge programs are critically reviewed over the last 30 years, and the key elements necessary for successful early discharge are reviewed and defined. Early discharge is clearly achievable for a large number of infants. Variations in neonatal care practices are reviewed since these variations have been documented to influence NICU stay. Management of apnea of prematurity and feeding practices is documented to significantly influence NICU length of stay, as is timing of discharge based on institutional factors. Developmentally centered care, use of nutritional supplements pre- and postdischarge, hearing screening programs, evaluation for retinopathy of prematurity, evaluation for apnea and bradycardia events, and cardiopulmonary stability while in a car seat all influence timing of discharge. Programs of early hospital discharge with home nursing and neonatologist support have been successful in lowering the length of NICU stay. However, trends in length of stay in NICUs indicate that for infants >750 g at birth over the last decade there have been insignificant reductions in length of hospital stay. Thus, because of the increase in the percentage of low birth weight infants in the US, there remain opportunities to improve on variations in care that will be translated to fewer NICU days in hospitals for selected infants. Several professional guidelines are summarized, and standards of care as related to discharge of premature infants are reviewed.
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PMID:Early NICU discharge of very low birth weight infants: a critical review and analysis. 1500 Nov 47


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