Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Persistent Fetal Circulation Syndrome”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources
PubMed1995

Pathophysiology of congenital diaphragmatic hernia. XVI: Elevated pulmonary collagen in the lamb model of congenital diaphragmatic hernia.

The pathophysiologic features of congenital diaphragmatic hernia (CDH) include pulmonary hypoplasia, pulmonary hypertension, surfactant deficiency, and decreased pulmonary compliance. When the surfactant deficiency is corrected using exogenous surfactant therapy, the pulmonary compliance improves, but does not reach normal values. Quasistatic saline pressure-volume measurements, which eliminate the air-liquid interface, confirm that CDH lungs are intrinsically less compliant than control lungs. The authors hypothesized that this abnormal lung compliance results from elevated concentrations of collagen and/or elastin in the lung. Therefore, they measured the collagen and elastin concentrations in CDH and control lung tissue. Also measured was the collagen concentration in the kidney, intestine, and dissected third-generation arterioles, venules, and bronchioles, to characterize further the pathology of CDH. The CDH model was created on the left side of fetuses in pregnant ewes at 80 days' gestation. The fetuses were delivered and killed at 140 days (full term, 145). The concentrations of collagen (as hydroxyproline), elastin, DNA, and total protein were measured using standard techniques. Although there was significantly more collagen per gram of lung tissue in the CDH lungs (1.334 mg/g v 0.885 mg/g in the controls) the elastin concentrations were not different. The elevated collagen concentration was not associated specifically with the conducting airways or vasculature. The collagen concentrations in CDH kidneys and intestines were the same as those of controls. The DNA/total protein ratios in the CDH and control lungs were identical. The results suggest that the elevated collagen concentration was present only in the lungs of CDH lambs, and that it was not attributable to atrophy or hypertrophy of the lungs. Thus, increased collagen in the lung parenchyma may be responsible for the intrinsic stiffness and decreased compliance of the CDH lungs.

Animals↗
PubMed1990

Serum PAF acetylhydrolase increases during neonatal maturation.

Acetylhydrolase is an acid-labile, 43 kd protein that catalyzes the degradation of platelet activating factor (PAF), a potent phospholipid inflammatory mediator, to its biologically inactive metabolite lysoPAF. PAF has a short half-life, thus acetylhydrolase plays an important role in its regulation. Since previous work suggests that PAF may be involved in certain neonatal diseases such as necrotizing enterocolitis, we studied the effect of age on acetylhydrolase activity. Serum acetylhydrolase activity was quantified using radio-labelled PAF and measuring reaction products. Serum samples were obtained prospectively from 70 subjects ranging in age from 4 hr to 48 yr. Acetylhydrolase activity was lower for newborns (less than 3 wk) than all other age ranges (8.2 +/- 1.4 nmole/ml/min vs 30.0 +/- 1.6 nmole/ml/min, p less than .01). Furthermore, enzyme activity increased linearly with respect to the natural logarithm of age from 0 days to 6 weeks (r = 0.65, p less than .001). By 6 weeks of life acetylhydrolase activity approached values of older children and adults. Newborn acetylhydrolase activity was similar between term and preterm infants (8.6 +/- 1.9 nmole/ml/min vs 7.2 +/- 2.4 nmole/ml/min, p = NS). We conclude that acetylhydrolase activity is low in human neonates and increases during the first 6 weeks of life. These results suggest that newborn infants may be at increased risk for pathophysiologic processes mediated by PAF.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed1992

Inhaled nitric oxide in persistent pulmonary hypertension of the newborn.

Nitric oxide (NO) has vasodilatory effects on the pulmonary vasculature in adults and animals. We examined the effects on systemic oxygenation and blood pressure of inhaling up to 80 parts per million by volume of NO at FiO2 0.9 for up to 30 minutes by 6 infants with persistent pulmonary hypertension of the newborn (PPHN). In all infants this treatment rapidly and significantly increased preductal oxygen saturation (SpO2); in 5 infants postductal SpO2 and oxygen tensions also increased. Inhalation of NO did not cause systemic hypotension or raise methaemoglobin. These data suggest that low levels of inhaled NO have an important role in the reversal of hypoxaemia due to PPHN.

Administration, Inhalation↗
PubMed1992

Low-dose inhalation nitric oxide in persistent pulmonary hypertension of the newborn.

We studied the effects of inhaled nitric oxide (NO) in 9 newborn infants with severe persistent pulmonary hypertension (PPHN) who were candidates for extracorporeal membrane oxygenation treatment. With low doses of NO (10-20 ppm) all showed rapid improvement in oxygenation without reduction of systemic blood pressure. In 6 infants treated with inhaled NO for 24 h, clinical improvement was sustained at 6 ppm.

Administration, Inhalation↗
PubMed1996

Delayed post-neonatal intensive care unit hearing disturbance.

Ten children, who developed hearing disturbance after discharge from the neonatal intensive care unit (NICU), are reported. All were born at full term, between November 1988 and November 1992, weighed at least 2500 g and had normal auditory brainstem response (ABR) at discharge from the NICU. All ten underwent thorough evaluation to determine the cause of the subsequent hearing loss. All had severe cardiovascular and/or pulmonary disorders at birth, and persistent pulmonary hypertension of the newborn (PPHN) was diagnosed in eight. A total of 25 PPHN cases were treated at our facility during the 1988-1992 period, the rate of hearing disturbance in PPHN patients being 32%. The 10 infants in this study were mechanically ventilated for, on average, 30 days. High frequency oxygenation (HFO) was required in five cases, extra corporeal membrane oxygenation (ECMO) in six. During this period, only eight ECMO-treated infants survived. The rate of hearing loss in surviving cases was therefore very high, 75% (6 8). All 10 of our cases were treated with an aminoglycoside, furosemide and a muscle relaxant. We recommend follow-up at 6 and 12 months of age, as these children are at very high risk of developing hearing disturbance.

Age of Onset↗
PubMed1988

Refractory neonatal hypoxemia: diagnostic evaluation and pharmacologic management.

Hypoxemia refractory to oxygen administration and assisted ventilation is found in many clinical conditions and results from a variety of pathophysiologic disorders. Recent clinical and laboratory experience has demonstrated that the choice of therapy for an infant with refractory hypoxemia depends upon identification of the underlying etiologic and pathophysiologic conditions. The ideal therapies for many of these conditions have not yet been defined. We have provided, based on our experience, guidelines for selection of the most appropriate of the currently available therapies for many of these patients.

Blood Pressure↗
PubMedDate not supplied

Seizures and infarction in neonates with persistent pulmonary hypertension.

Seizures and cerebral infarction were observed in 10 near-term (greater than 36 weeks gestation) and term infants who had experienced moderate to severe peripartum asphyxia which resulted in persistent pulmonary hypertension. No patient received extracorporeal membrane oxygenation. Eight were outborn. Five patients were diagnosed initially with seizures during electroencephalography; electrical status epilepticus was demonstrated in five patients. The location of electrical seizures corresponded to the area of infarction in seven patients; the two remaining patients had white matter infarction. Prompt recognition of seizures and infarction in patients with persistent pulmonary hypertension is essential because of the higher probability of later neurodevelopmental difficulties.

Cerebral Infarction↗
PubMedDate not supplied

The transitional circulation: physiology and anesthetic implications.

Over the past decade, several aspects of the physiology of the transitional circulation have been elucidated. The transitional circulation may be viewed as a process divided into four phases. The concept of these phases underscores the fact that the normal transitional circulation should be viewed as an orderly process and not a single event. Within these phases, several mechanisms seem to be involved in the control of pulmonary vascular resistance (PVR). Yet even these mechanisms do not completely explain the process of the normal transition, and very little is understood about why the transition occasionally fails. No doubt other as yet undescribed mechanisms also play a role. Much work remains to be done in the study of the normal and abnormal transitional circulation. The profound hypoxia that characterizes infants with failed transitional circulation from any cause is due to a persistently high PVR, causing right-to-left shunting at the ductal and foramental levels. Clinical care of these infants is based on efforts to simultaneously decrease PVR and increase systemic vascular resistance (SVR). Appropriate measures include the use of supplemental oxygen, hyperventilation, alkalinization, and sedation to decrease PVR and intravenous (IV) fluids and pressors to increase SVR. The rapidly fluctuating nature of the physiologic processes that cause failure of the transitional circulation must be kept in mind when caring for these infants, both during initial stabilization in the delivery room and while administering anesthesia for surgical repair of congenital defects.

Anesthesia, General↗
PubMed2004

New approaches for persistent pulmonary hypertension of newborn.

The management of PPHN entered a new era with the development of inhaled NO therapy for the relief of pulmonary hypertension. The wider application of INO therapy and improved ventilation strategies led to a decrease in the need for invasive life-sustaining therapies such as ECMO. The remarkable advances in the understanding and treatment of PPHN were made possible by the extensive investigations in the laboratory using animal models. Further decreases in morbidity and mortality are possible with specific strategies targeted to correct the alterations in NO and prostacyclin biology and strategies to reduce lung injury. Further research is needed to understand the basis for the biologic susceptibility of some infants to environmental insults such as intra-uterine stressor exposure to NSAIDs in utero.

Administration, Inhalation↗
PubMed2004

Expanding the phenotype of alveolar capillary dysplasia (ACD).

OBJECTIVES: To define the phenotype of congenital alveolar capillary dysplasia (ACD) as a first step toward mapping the responsible gene(s). STUDY DESIGN: Analysis of pathology reports and microscopic slides of 23 subjects with ACD and sequence analysis of two candidate genes. RESULTS: Our review of the pre- and postmortem records delineates both the natural history of this condition and the associated anomalies. Our collection of families corroborates the likely autosomal recessive nature of this condition in some families and provides additional data for genetic and prenatal counseling. Anomalies of many organ systems were detected either in the prenatal period or during the hospital course. However, some major anomalies were not detected until postmortem examination. Left-right asymmetry and gastrointestinal malrotation emerge as important, previously recognized but underappreciated phenotypic features of ACD. Finally, we used sequence analysis to exclude mutations in the coding region of two candidate genes, bone morphogenetic protein type II receptor (BMPR2) and endothelial monocyte-activating polypeptide II (EMAP II), as candidates for ACD. CONCLUSIONS: Understanding the clinical spectrum of ACD and the cloning of an "ACD gene" both have implications for counseling, for prenatal testing, and for understanding the molecular pathophysiology of ACD and other organ malformations that are associated with this condition.

Abnormalities, Multiple↗