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Lorthe E, Marchand-Martin L, Letouzey M, Aubert AM, Pierrat V, Benhammou V, Delorme P, Marret S, Ancel PY, Goffinet F, L'Hélias LF, Kayem G. Tocolysis after preterm prelabor rupture of membranes and 5-year outcomes: a population-based cohort study. Am J Obstet Gynecol 2024; 230:570.e1-570.e18. [PMID: 37827270 DOI: 10.1016/j.ajog.2023.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/29/2023] [Accepted: 10/06/2023] [Indexed: 10/14/2023]
Abstract
BACKGROUND The administration of tocolytics after preterm prelabor rupture of membranes remains a controversial practice. In theory, reducing uterine contractility should delay delivery and allow for optimal antenatal management, thereby reducing the risks for prematurity and adverse consequences over the life course. However, tocolysis may be associated with neonatal death or long-term adverse neurodevelopmental outcomes, mainly related to prolonged fetal exposure to intrauterine infection or inflammation. In a previous study, we showed that tocolysis administration was not associated with short-term benefits. There are currently no data available to evaluate the impact of tocolysis on neurodevelopmental outcomes in school-aged children born prematurely in this clinical setting. OBJECTIVE This study aimed to investigate whether tocolysis administered after preterm prelabor rupture of membranes is associated with neurodevelopmental outcomes at 5.5 years of age. STUDY DESIGN We used data from a prospective, population-based cohort study of preterm births recruited in 2011 (referred to as the EPIPAGE-2 study) and for whom the results of a comprehensive medical and neurodevelopmental assessment of the infant at age 5.5 years were available. We included pregnant individuals with preterm prelabor rupture of membranes at 24 to 32 weeks' gestation in singleton pregnancies with a live fetus at the time of rupture, birth at 24 to 34 weeks' gestation, and participation of the infant in an assessment at 5.5 years of age. Exposure was the administration of any tocolytic treatment after preterm prelabor rupture of membranes. The main outcome was survival without moderate to severe neurodevelopmental disabilities at 5.5 years of age. Secondary outcomes included survival without any neurodevelopmental disabilities, cerebral palsy, full-scale intelligence quotient, developmental coordination disorders, and behavioral difficulties. A propensity-score analysis was used to minimize the indication bias in the estimation of the treatment effect on outcomes. RESULTS Overall, 596 of 803 pregnant individuals (73.4%) received tocolytics after preterm prelabor rupture of membranes. At the 5.5-year follow-up, 82.7% and 82.5% of the children in the tocolysis and no tocolysis groups, respectively, were alive without moderate to severe neurodevelopmental disabilities; 52.7% and 51.1%, respectively, were alive without any neurodevelopmental disabilities. After applying multiple imputations and inverse probability of treatment weighting, we found no association between the exposure to tocolytics and survival without moderate to severe neurodevelopmental disabilities (odds ratio, 0.93; 95% confidence interval, 0.55-1.60), survival without any neurodevelopmental disabilities (odds ratio, 1.02; 95% confidence interval, 0.65-1.61), or any of the other outcomes. CONCLUSION There was no difference in the neurodevelopmental outcomes at age 5.5 years among children with and without antenatal exposure to tocolysis after preterm prelabor rupture of membranes. To date, the health benefits of tocolytics remain unproven, both in the short- and long-term.
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Affiliation(s)
- Elsa Lorthe
- Unit of Population Epidemiology, Department of Primary Care Medicine, Geneva University Hospitals, Geneva, Switzerland; Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France.
| | - Laetitia Marchand-Martin
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France
| | - Mathilde Letouzey
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France; Department of Neonatal Pediatrics, Poissy Saint Germain Hospital, Poissy, France
| | - Adrien M Aubert
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France
| | - Véronique Pierrat
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France; Department of Neonatology, Centre Hospitalier Intercommunal Créteil, Créteil, France
| | - Valérie Benhammou
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France
| | - Pierre Delorme
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France; Department of Gynecology and Obstetrics, Armand Trousseau Hospital, APHP, FHU Prema, Paris Sorbonne University, Paris, France
| | - Stéphane Marret
- Department of Neonatal Pediatrics, Intensive Care, and Neuropediatrics, Rouen University Hospital, Rouen, France; Inserm Unit 1245, Team Perinatal Handicap, School of Medicine of Rouen, Normandy University, Normandy, France
| | - Pierre-Yves Ancel
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France; Clinical Research Unit, Center for Clinical Investigation P1419, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - François Goffinet
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France; AP-HP Centre, Maternité Port-Royal, Department of Obstetrics and Gynaecology, Université Paris Cité, FHU PREMA, Paris, France
| | - Laurence Foix L'Hélias
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France; Department of Neonatal Pediatrics, Armand Trousseau Hospital, APHP, FHU Prema, Paris Sorbonne University, Paris, France
| | - Gilles Kayem
- Université Paris Cité, Inserm, INRAE, Centre for Research in Epidemiology and Statistics (CRESS), Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), Paris, France; Department of Gynecology and Obstetrics, Armand Trousseau Hospital, APHP, FHU Prema, Paris Sorbonne University, Paris, France
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Nijman TAJ, Goedhart MM, Naaktgeboren CN, de Haan TR, Vijlbrief DC, Mol BW, Benders MJN, Franx A, Oudijk MA. Effect of nifedipine and atosiban on perinatal brain injury: secondary analysis of the APOSTEL-III trial. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2018; 51:806-812. [PMID: 28452086 DOI: 10.1002/uog.17512] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 04/03/2017] [Accepted: 04/11/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVE Brain injury in neonates born prematurely is associated strongly with poor neurodevelopmental outcome. The aim of this study was to evaluate whether tocolysis with nifedipine or atosiban in women with threatened preterm birth can reduce the incidence of overall brain injury in neonates born prematurely. METHODS This was a secondary analysis of the APOSTEL-III trial (Dutch Clinical Trial Registry, no. NTR2947), a randomized clinical trial in which women with threatened preterm labor between 25 and 34 weeks of gestation were allocated to treatment with nifedipine or atosiban. In this secondary analysis, women delivered at ≤ 32 weeks of gestational age in the two main contributing centers were included. Primary outcome was the presence of neonatal brain injury, which was defined as presence of abnormalities on ultrasound investigation and classified into mild and severe. To evaluate type and severity of brain injury, all neonatal ultrasounds performed during neonatal intensive and medium care admission were analyzed. To test the robustness of our results, a sensitivity analysis was performed assessing differences in baseline or known risk factors for brain injury. RESULTS A total of 117 neonates (from 102 women) were studied, of which 51 had been exposed to nifedipine and 66 to atosiban. Brain injury was observed in 22 (43.1%) neonates in the nifedipine group compared with 37 (56.1%) in the atosiban group (OR, 0.60; 95% CI, 0.29-1.24). Presence of mild brain injury was comparable between the nifedipine (33.3%) and atosiban (48.5%) groups (OR, 0.53; 95% CI, 0.25-1.13). Severe brain injury was also comparable between the groups, observed in 9.8% of neonates in the nifedipine vs 7.6% of those in the atosiban group (OR, 1.33; 95% CI, 0.36-4.85). Intraventricular hemorrhage (≥ Grade I) was the most frequently seen ultrasound abnormality, observed in 18 (35.3%) neonates in the nifedipine group vs 25 (37.9%) in the atosiban group (OR, 0.90; 95% CI, 0.42-1.91). The sensitivity analysis, with adjustment for maternal age and gestational age at randomization, showed no statistical difference between the groups for presence of brain injury (OR, 0.58; 95% CI, 0.27-1.27). CONCLUSION In children born before 32 weeks of gestation after the use of tocolytics, the prevalence of brain injury was high. No significant differences were found with respect to overall brain injury between neonates exposed to nifedipine and those exposed to atosiban. However, as this study was a secondary analysis of the APOSTEL III trial, it was underpowered for brain injury. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
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Affiliation(s)
- T A J Nijman
- Department of Obstetrics and Gynecology, University Medical Center Utrecht, Utrecht, The Netherlands
- Department of Obstetrics and Gynecology, Haaglanden Medical Center, The Hague, The Netherlands
| | - M M Goedhart
- Department of Obstetrics and Gynecology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - C N Naaktgeboren
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - T R de Haan
- Department of Neonatology, Academic Medical Center, Amsterdam, The Netherlands
| | - D C Vijlbrief
- Department of Neonatology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - B W Mol
- The Robinson Research Institute, School of Pediatrics and Reproductive Health and The South Australian Health and Medical Research Institute, University of Adelaide, Adelaide, Australia
| | - M J N Benders
- Department of Neonatology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - A Franx
- Department of Obstetrics and Gynecology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - M A Oudijk
- Department of Obstetrics and Gynecology, University Medical Center Utrecht, Utrecht, The Netherlands
- Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, The Netherlands
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Berger R, Garnier Y, Jensen A. Perinatal Brain Damage: Underlying Mechanisms and Neuroprotective Strategies. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/107155760200900601] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Richard Berger
- Department of Obstetrics and Gynecology, University of Bochum, Bochum, Germany; Universitätsfrauenklinik Bochum, Knappschaftskrankenhaus, In der Schornau 23-25, 44982 Bochum, Germany
| | | | - Arne Jensen
- Department of Obstetrics and Gynecology, University of Bochum, Bochum, Germany
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Efficacy and Tolerability of Topical 0.05% Flunarizine in Patients With Open-angle Glaucoma or Ocular Hypertension—A Pilot Study. J Glaucoma 2011; 20:519-22. [DOI: 10.1097/ijg.0b013e3181f3eb34] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Fan X, Kavelaars A, Heijnen CJ, Groenendaal F, van Bel F. Pharmacological neuroprotection after perinatal hypoxic-ischemic brain injury. Curr Neuropharmacol 2011; 8:324-34. [PMID: 21629441 PMCID: PMC3080590 DOI: 10.2174/157015910793358150] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Revised: 03/31/2010] [Accepted: 04/08/2010] [Indexed: 11/22/2022] Open
Abstract
Perinatal hypoxia-ischemia (HI) is an important cause of neonatal brain injury. Recent progress in the search for neuroprotective compounds has provided us with several promising drugs to reduce perinatal HI-induced brain injury. In the early stage (first 6 hours after birth) therapies are concentrated on prevention of the production of reactive oxygen species or free radicals (xanthine-oxidase-, nitric oxide synthase-, and prostaglandin inhibition), anti-inflammatory effects (erythropoietin, melatonin, Xenon) and anti-apoptotic interventions (nuclear factor kappa B- and c-jun N-terminal kinase inhibition); in a later stage stimulation of neurotrophic properties in the neonatal brain (erythropoietin, growth factors) can be targeted to promote neuronal and oligodendrocyte regeneration. Combination of pharmacological means of treatment with moderate hypothermia, which is accepted now as a meaningful therapy, is probably the next step in clinical treatment to fight post-asphyxial brain damage. Further studies should be directed at a more rational use of therapies by determining the optimal time and dose to inhibit the different potentially destructive molecular pathways or to enhance endogenous repair while at the same time avoiding adverse effects of the drugs used.
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Affiliation(s)
- Xiyong Fan
- Department of Neonatology, University Medical Center, Utrecht, the Netherlands
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Effect of flunarizine, a calcium channel blocker, on intraocular pressure and aqueous humor dynamics in monkeys. J Glaucoma 2008; 17:73-8. [PMID: 18303390 DOI: 10.1097/ijg.0b013e318133a845] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the effects of flunarizine, a nonselective calcium channel blocker, on intraocular pressure (IOP) in monkeys with laser-induced unilateral glaucoma and on aqueous humor dynamics in normal monkeys. METHODS The IOP was measured before and hourly for 6 hours after single-dose administration of 0.5%, 1%, or 2% flunarizine to the glaucomatous eye of 8 monkeys with unilateral laser-induced glaucoma. In a separate multiple-dose study, 0.5% flunarizine was applied twice daily for 5 consecutive days to the glaucomatous eye of the same 8 monkeys. IOP was measured at untreated baseline, after treatment with vehicle only, and on treatment days 1, 3, and 5. Tonographic outflow facility and fluorophotometric flow rates of aqueous humor were measured in 7 normal monkeys before and after the fifth dose of twice-daily treatment with 0.5% flunarizine. RESULTS Unilateral application of 50 microL of 0.5%, 1%, or 2% flunarizine reduced IOP bilaterally. In the treated glaucomatous eyes, flunarizine reduced the IOP for 2, 3, or 5 hours, with a maximum reduction of 2.5+/-0.5 (mean+/-SEM) mm Hg (9%), 3.0+/-0.4 mm Hg (10%), and 5.0+/-0.8 mm Hg (18%) following the 0.5%, 1%, and 2% concentrations, respectively (P<0.01). The maximum reductions in IOP in the contralateral untreated eyes were 1.3+/-0.5 mm Hg, 1.5+/-0.3 mm Hg, and 2.9+/-0.7 mm Hg following the 0.5%, 1%, and 2% concentrations, respectively (P<0.05). Both the magnitude and duration of the ocular hypotensive effect of 0.5% flunarizine were enhanced with twice-daily administration for 5 days. Outflow facility in normal monkey eyes was increased (P<0.05) by 39% in the treated eyes compared with vehicle-treated contralateral eyes and by 41% compared with baseline values, and aqueous humor flow rates were unchanged (P>0.30). CONCLUSIONS Flunarizine reduces IOP in a dose-dependent manner when administered to glaucomatous monkey eyes, but also has an ocular hypotensive effect on the contralateral untreated eyes. An increase in tonographic outflow facility seems to account for the IOP reduction in normal monkey eyes.
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Gabriel R, Grolier F, Graesslin O. Can obstetric care provide further improvement in the outcome of preterm infants? Eur J Obstet Gynecol Reprod Biol 2005; 117 Suppl 1:S25-8. [PMID: 15530712 DOI: 10.1016/j.ejogrb.2004.07.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Reducing the incidence of cerebral damage in preterm infants has become a major objective of perinatal medicine. Recent studies have shown that intrapartum hypoxia is implicated in only 10% of cases, whereas prenatal factors are significantly linked with such damage. The main risk factors associated with cerebral palsy are preterm birth, multiple pregnancy, intrauterine infection, serious hypoxaemic and haemodynamic disorders and, possibly, thrombophilic disorders. Recent progress in recognition of the pathogenesis of cerebral white matter damage has underlined the roles of cytokines, including interleukins 1 and 6 and tumour necrosis factor alpha (TNFalpha), and of a massive release of glutamate, which leads to the excitotoxic cascade. Three measures have had demonstrable benefits in improving neonatal outcome in preterm infants: a policy of prenatal transfers to tertiary level care units, antenatal corticosteroid therapy, and administration of antibiotics to women with preterm premature rupture of membranes. The influence of tocolysis is usually considered to be relatively minor, but further studies in very preterm pregnancies may be required. The recent development of tocolytics without major adverse effects will probably facilitate such studies. The mode of delivery of early preterm infants is another important area of controversy. Recent studies have suggested that a policy of elective caesarean section in PPROM and in the case of breech presentation of fetuses weighing less than 1000-1500 g would be beneficial. Lastly, in vitro and animal studies have shown that several pharmacological agents can prevent white matter disease by interacting with cytokine and the excitotoxic cascade. This will probably constitute an important area of research in the future.
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Affiliation(s)
- René Gabriel
- Institut Mère Enfant Alix de Champagne, Centre Hospitalier Universitaire, 51092 Reims Cedex, France.
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Berger R, Middelanis J, Vaihinger HM, Mies G, Wilken B, Jensen A. Creatine protects the immature brain from hypoxic-ischemic injury. ACTA ACUST UNITED AC 2004; 11:9-15. [PMID: 14706677 DOI: 10.1016/j.jsgi.2003.07.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE We tested the neuroprotective effects of creatine against hypoxic-ischemic injury in the immature brain. METHODS Hippocampal slices were prepared from fetal guinea pigs at 0.9 gestation and incubated in artificial cerebrospinal fluid (aCSF) equilibrated with carbogen. Slices were subjected to oxygen-glucose deprivation (OGD) for 30 or 40 minutes. Two hours after OGD, adenosine triphosphate (ATP) and protein synthesis were analyzed. Creatine (3 mM) was applied to tissue slices of the study groups 2 hours before the insult. In a second set of experiments 7-day-old Wistar rats were anesthetized, and the left carotid artery was ligated. After 1 hour of recovery the pups were subjected to a hypoxic gas mixture (8% oxygen and 92% nitrogen) for 80 minutes. Seven days later the brains of the neonates were removed and analyzed for hypoxic-ischemic injury. The rat pups of the test group were treated with creatine (3 g/kg subcutaneously) before (-64 hours, -40 hours, and -16 hours) and after (+3 hours) the hypoxic-ischemic insult, with zero time corresponding to the start of hypoxia, whereas the animals of the control group received the solvent. RESULTS Creatine significantly improved the recovery of protein synthesis 2 hours after OGD in hippocampal slices but had no effect on ATP levels. Whereas seven animals of the control group developed severe cystic cerebral infarction, only mild to moderate damage was observed in the rat pups of the study group. In contrast to creatine-treated pups, the volume of the ipsilateral hemisphere was considerably smaller than that of the contralateral one in control animals (104 +/- 22 versus 138 +/- 14 mL, P<.001). Except at the frontal level (A 6.0 mm), neuronal cell injury was significantly lower in the cortex of the animals that had received creatine. This was also true for the evaluated subfields in the hippocampus. CONCLUSION We conclude that creatine protects the immature brain from hypoxic-ischemic injury.
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Affiliation(s)
- Richard Berger
- Department of Obstetrics and Gynecology, University of Bochum, Bochum, Germany.
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Jensen A, Garnier Y, Middelanis J, Berger R. Perinatal brain damage--from pathophysiology to prevention. Eur J Obstet Gynecol Reprod Biol 2003; 110 Suppl 1:S70-9. [PMID: 12965093 DOI: 10.1016/s0301-2115(03)00175-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Children undergoing perinatal brain injury often suffer from the dramatic consequences of this misfortune for the rest of their lives. Despite the severe clinical and socio-economic significance, no effective clinical strategies have yet been developed to counteract this condition. This review describes the pathophysiological mechanisms that are implicated in perinatal brain injury. These include the acute breakdown of neuronal membrane potential followed by the release of excitatory amino acids such as glutamate and aspartate. Glutamate binds to postsynaptically located glutamate receptors that regulate calcium channels. The resulting calcium influx activates proteases, lipases and endonucleases which in turn destroy the cellular skeleton. The acute lack of cellular energy during ischemia induces almost complete inhibition of cerebral protein biosynthesis. Once the ischemic period is over, protein biosynthesis returns to preischemic levels in non-vulnerable regions of the brain, while in more vulnerable areas it remains inhibited. A second wave of neuronal cell damage occurs during the reperfusion phase induced by the postischemic release of oxygen radicals, synthesis of nitric oxide (NO), inflammatory reactions and an imbalance between the excitatory and inhibitory neurotransmitter systems. Clinical studies have shown that intrauterine infection increases the risk of periventricular white matter damage especially in the immature fetus. This damage may be mediated by cardiovascular effects of endotoxins leading to cerebral hypoperfusion and by activation of apoptotic pathways in oligodendrocyte progenitors through the release of pro-inflammatory cytokines. Knowledge of these pathophysiological mechanisms has enabled scientists to develop new therapeutic strategies which have been shown to be neuroprotective in animal experiments. The potential of such therapies is discussed here, particularly the promising effects of postischemic induction of mild cerebral hypothermia, the application of the calcium-antagonist flunarizine and the administration of magnesium.
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Affiliation(s)
- Arne Jensen
- Department of Obstetrics and Gynecology, Universitätsfrauenklinik Bochum, Knappschaftskrankenhaus, In der Schornau 23-25, 44982 Bochum, Germany.
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Coumans ABC, Middelanis JS, Garnier Y, Vaihinger HM, Leib SL, Von Duering MU, Hasaart THM, Jensen A, Berger R. Intracisternal application of endotoxin enhances the susceptibility to subsequent hypoxic-ischemic brain damage in neonatal rats. Pediatr Res 2003; 53:770-5. [PMID: 12621122 DOI: 10.1203/01.pdr.0000059221.40073.82] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Perinatal brain damage is associated not only with hypoxic-ischemic insults but also with intrauterine inflammation. A combination of antenatal inflammation and asphyxia increases the risk of cerebral palsy >70 times. The aim of the present study was to determine the effect of intracisternal (i.c.) administration of endotoxin [lipopolysaccharides (LPS)] on subsequent hypoxic-ischemic brain damage in neonatal rats. Seven-day-old Wistar rats were subjected to i.c. application of NaCl or LPS (5 microg/pup). One hour later, the left common carotid artery was exposed through a midline neck incision and ligated with 6-0 surgical silk. After another hour of recovery, the pups were subjected to a hypoxic gas mixture (8% oxygen/92% nitrogen) for 60 min. The animals were randomized to four experimental groups: 1) sham control group, left common carotid artery exposed but not ligated (n = 5); 2) LPS group, subjected to i.c. application of LPS (n = 7); 3) hypoxic-ischemic study group, i.c. injection of NaCl and exposure to hypoxia after ligation of the left carotid artery (n = 17); or 4) hypoxic-ischemic/LPS study group, i.c. injection of LPS and exposure to hypoxia after ligation of the left carotid artery (n = 19). Seven days later, neonatal brains were assessed for neuronal cell damage. In a second set of experiments, rat pups received an i.c. injection of LPS (5 microg/pup) and were evaluated for tumor necrosis factor-alpha expression by immunohistochemistry. Neuronal cell damage could not be observed in the sham control or in the LPS group. In the hypoxic-ischemic/LPS group, neuronal injury in the cerebral cortex was significantly higher than in animals that were subjected to hypoxia/ischemia after i.c. application of NaCl. Injecting LPS intracisternally caused a marked expression of tumor necrosis factor-alpha in the leptomeninges. Applying LPS intracisternally sensitizes the immature rat brain to a subsequent hypoxic-ischemic insult.
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Affiliation(s)
- Audrey B C Coumans
- Department of Obstetrics and Gynecology, University Hospital Maastricht, The Netherlands
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Abstract
Investigations in animal models of hypoxic-ischemic injury have not translated into clinical trials of success because of the complex pathology of hypoxic-ischemic brain injury in neonates, the difficulty in defining the onset and duration and severity of the injury, the underlying predisposing disorders of the mothers or the infant, the side effects of many of the investigational drugs precluded clinical use, and many of the investigational agents interfered with only one step of the cascade of events that lead to brain injury. It is possible that a combination of therapeutic agents, including those that affect different levels of the cascade to cell death, will have the greatest neuroprotective effects. Modest hypothermia postpones secondary energy failure and can prolong the window while pharmacotherapeutic agents can be used. It is possible that in the future, sequential administration of agents or strategies that are initiated in the intrapartum period and continued postnatally will be the optimum method for treating infants who are at highest risk for brain injury following acute hypoxic-ischemic asphyxia.
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Affiliation(s)
- Seetha Shankaran
- Neonatal-Perinatal Medicine, Wayne State University School of Medicine, 3901 Beaubien Blvd, Detroit, MI 48201, USA.
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Calvert JW, Yin W, Patel M, Badr A, Mychaskiw G, Parent AD, Zhang JH. Hyperbaric oxygenation prevented brain injury induced by hypoxia-ischemia in a neonatal rat model. Brain Res 2002; 951:1-8. [PMID: 12231450 DOI: 10.1016/s0006-8993(02)03094-9] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The occurrence of hypoxia-ischemia (HI) during early fetal or neonatal stages of an individual leads to the damaging of immature neurons resulting in behavioral and psychological dysfunctions, such as motor or learning disabilities, cerebral palsy, epilepsy or even death. No effective treatment is currently available and this study is the first to use hyperbaric oxygen (HBO) as a treatment for neonatal HI. Herein, we sought out to determine if HBO is able to offer neuroprotectivity against an HI insult. Seven-day-old rat pups were subjected to unilateral carotid artery ligation followed by 2.5 h of hypoxia (8% O(2) at 37 degrees C). HBO treatment was administered by placing pups in a chamber (3 ATA for 1 h) 1 h after hypoxia exposure. Brain injury was assessed based on ipsilateral hemispheric weight divided by contralateral hemispheric weight, light microscopy, and EM. Sensorimotor functional tests were administered at 5 weeks after hypoxia exposure. After HI, the ipsilateral hemisphere was 52.65 and 57.64% (P<0.001) of the contralateral hemisphere at 2 and 6 weeks, respectively. In HBO treated groups, the ipsilateral hemisphere was 77.77 and 84.19% (P<0.001) at 2 and 6 weeks. There was much less atrophy and apoptosis in HBO treated animals under light or electron microscopy. Sensorimotor function was also improved by HBO at 5 weeks after hypoxia exposure (Chi-square, P<0.050). The results suggest that HBO is able to attenuate the effects of HI on the neonatal brain by reducing the progression of neuronal injury and increasing sensorimotor function.
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Affiliation(s)
- John W Calvert
- Department of Neurosurgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
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Cornette L, Levene MI. Post-resuscitative management of the asphyxiated term and preterm infant. SEMINARS IN NEONATOLOGY : SN 2001; 6:271-82. [PMID: 11520192 DOI: 10.1053/siny.2001.0055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Up until the recent past, the treatment for perinatal asphyxia included only supportive measures. Babies were resuscitated and then observed for signs of multi-organ system dysfunction. Apart from standard supportive management, a new arsenal of potential neuroprotective strategies have emerged over the past years, in order to decrease the severity of brain injury following asphyxia. Today, several neuroprotective therapies are being evaluated in human infants.
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Affiliation(s)
- L Cornette
- Division of Paediatrics and Child Health, Leeds General Infirmary, Leeds, UK.
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14
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Abstract
Perinatal brain damage in the mature fetus is usually brought about by severe intrauterine asphyxia following an acute reduction of the uterine or umbilical circulation. The areas most heavily affected are the parasagittal region of the cerebral cortex and the basal ganglia. The fetus reacts to a severe lack of oxygen with activation of the sympathetic-adrenergic nervous system and a redistribution of cardiac output in favor of the central organs (brain, heart and adrenals). If the asphyxic insult persists, the fetus is unable to maintain circulatory centralization, and the cardiac output and extent of cerebral perfusion fall. Owing to the acute reduction in oxygen supply, oxidative phosphorylation in the brain comes to a standstill. The Na+/K+ pump at the cell membrane has no more energy to maintain the ionic gradients. In the absence of a membrane potential, large amounts of calcium ions flow through the voltage-dependent ion channels, down an extreme extra-/intracellular concentration gradient, into the cell. Current research suggests that the excessive increase in levels of intracellular calcium, so-called calcium overload, leads to cell damage through the activation of proteases, lipases and endonucleases. During ischemia, besides the influx of calcium ions into the cells via voltage-dependent calcium channels, more calcium enters the cells through glutamate-regulated ion channels. Glutamate, an excitatory neurotransmitter, is released from presynaptic vesicles during ischemia following anoxic cell depolarization. The acute lack of cellular energy arising during ischemia induces almost complete inhibition of cerebral protein biosynthesis. Once the ischemic period is over, protein biosynthesis returns to preischemic levels in non-vulnerable regions of the brain, while in more vulnerable areas it remains inhibited. The inhibition of protein synthesis, therefore, appears to be an early indicator of subsequent neuronal cell death. A second wave of neuronal cell damage occurs during the reperfusion phase. This cell damage is thought to be caused by the postischemic release of oxygen radicals, synthesis of nitric oxide (NO), inflammatory reactions and an imbalance between the excitatory and inhibitory neurotransmitter systems. Part of the secondary neuronal cell damage may be caused by induction of a kind of cellular suicide programme known as apoptosis. Interestingly, there is increasing evidence from recent clinical studies that perinatal brain damage is closely associated with ascending intrauterine infection before or during birth. However, a major part of this damage is likely to be of hypoxic-ischemic nature due to LPS-induced effects on fetal cerebral circulation. Knowledge of these pathophysiological mechanisms has enabled scientists to develop new therapeutic strategies with successful results in animal experiments. The potential of such therapies is discussed here, particularly the promising effects of intravenous administration of magnesium or postischemic induction of cerebral hypothermia.
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Affiliation(s)
- R Berger
- Department of Obstetrics and Gynecology, Ruhr-University, Bochum, Germany.
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15
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Abstract
Hypoxic-ischemic encephalopathy (HIE) in neonates is often difficult to diagnose in "real time" at the bedside because of the variety of disorders that can cause neonatal seizures and other nonspecific signs of encephalopathy. Standard interventions to support respiratory and cardiovascular disorders associated with HIE are appropriate, but none has been demonstrated to alter neurologic outcome. Anticonvulsants are indicated when seizures are observed, although they are considered a sign of HIE rather than a cause of injury. There is overwhelming evidence that the excitotoxic cascade that evolves during HIE extends over several days after the insult and is modifiable. Clinical trials of potentially neuroprotective interventions such as hypothermia are under way.
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Berger R, Garnier Y. Pathophysiology of perinatal brain damage. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1999; 30:107-34. [PMID: 10525170 DOI: 10.1016/s0165-0173(99)00009-0] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Perinatal brain damage in the mature fetus is usually brought about by severe intrauterine asphyxia following an acute reduction of the uterine or umbilical circulation. The areas most heavily affected are the parasagittal region of the cerebral cortex and the basal ganglia. The fetus reacts to a severe lack of oxygen with activation of the sympathetic-adrenergic nervous system and a redistribution of cardiac output in favour of the central organs (brain, heart and adrenals). If the asphyxic insult persists, the fetus is unable to maintain circulatory centralisation, and the cardiac output and extent of cerebral perfusion fall. Owing to the acute reduction in oxygen supply, oxidative phosphorylation in the brain comes to a standstill. The Na(+)/K(+) pump at the cell membrane has no more energy to maintain the ionic gradients. In the absence of a membrane potential, large amounts of calcium ions flow through the voltage-dependent ion channel, down an extreme extra-/intracellular concentration gradient, into the cell. Current research suggests that the excessive increase in levels of intracellular calcium, so-called calcium overload, leads to cell damage through the activation of proteases, lipases and endonucleases. During ischemia, besides the influx of calcium ions into the cells via voltage-dependent calcium channels, more calcium enters the cells through glutamate-regulated ion channels. Glutamate, an excitatory neurotransmitter, is released from presynaptic vesicles during ischemia following anoxic cell depolarisation. The acute lack of cellular energy arising during ischemia induces almost complete inhibition of cerebral protein biosynthesis. Once the ischemic period is over, protein biosynthesis returns to pre-ischemic levels in non-vulnerable regions of the brain, while in more vulnerable areas it remains inhibited. The inhibition of protein synthesis, therefore, appears to be an early indicator of subsequent neuronal cell death. A second wave of neuronal cell damage occurs during the reperfusion phase. This cell damage is thought to be caused by the post-ischemic release of oxygen radicals, synthesis of nitric oxide (NO), inflammatory reactions and an imbalance between the excitatory and inhibitory neurotransmitter systems. Part of the secondary neuronal cell damage may be caused by induction of a kind of cellular suicide programme known as apoptosis. Knowledge of these pathophysiological mechanisms has enabled scientists to develop new therapeutic strategies with successful results in animal experiments. The potential of such therapies is discussed here, particularly the promising effects of i.v. administration of magnesium or post-ischemic induction of cerebral hypothermia.
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Affiliation(s)
- R Berger
- Department of Obstetrics and Gynecology, University of Bochum, Bochum, Germany. richard.berger2ruhr-uni-bochum.de
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