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Chioma R, Finn D, Healy DB, Herlihy I, Livingstone V, Panaviene J, Dempsey EM. Impact of cord clamping on haemodynamic transition in term newborn infants. Arch Dis Child Fetal Neonatal Ed 2024; 109:287-293. [PMID: 38071517 DOI: 10.1136/archdischild-2023-325652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 10/27/2023] [Indexed: 04/20/2024]
Abstract
OBJECTIVE To assess the haemodynamic consequences of cord clamping (CC) in healthy term infants. DESIGN Cohort study. SETTING Tertiary maternity hospital. PATIENTS 46 full-term vigorous infants born by caesarean section. INTERVENTIONS Echocardiography was performed before CC, immediately after CC and at 5 min after birth. MAIN OUTCOME MEASURES Pulsed wave Doppler-derived cardiac output and the pulmonary artery acceleration time indexed to the right ventricle ejection time were obtained. As markers of loading fluctuations, the myocardial performance indexes and the velocities of the tricuspid and mitral valve annuli were determined with tissue Doppler imaging. Heart rate was derived from Doppler imaging throughout the assessments. RESULTS Left ventricular output increased throughout the first minutes after birth (mean (SD) 222.4 (32.5) mL/kg/min before CC vs 239.7 (33.6) mL/kg/min at 5 min, p=0.01), while right ventricular output decreased (306.5 (48.2) mL/kg/min before vs 272.8 (55.5) mL/kg/min immediately after CC, p=0.001). The loading conditions of both ventricles were transiently impaired by CC, recovering at 5 min. Heart rate progressively decreased after birth, following a linear trend temporarily increased by CC. The variation in left ventricular output across the CC was directly correlated to the fluctuation of left ventricular preload over the same period (p=0.03). CONCLUSIONS This study illustrates the cardiovascular consequences of CC in term vigorous infants and offers insight into the haemodynamic transition from fetal to neonatal circulation in spontaneously breathing newborns. Strategies that aim to enhance left ventricular preload before CC may prevent complications of perinatal cardiovascular imbalance.
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Affiliation(s)
- Roberto Chioma
- University College Cork, INFANT Research Centre, Cork, Ireland
- Università Cattolica del Sacro Cuore, Roma, Italy
| | - Daragh Finn
- University College Cork, INFANT Research Centre, Cork, Ireland
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland
| | - David B Healy
- University College Cork, INFANT Research Centre, Cork, Ireland
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland
| | - Ita Herlihy
- University College Cork, INFANT Research Centre, Cork, Ireland
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland
| | - Vicki Livingstone
- University College Cork, INFANT Research Centre, Cork, Ireland
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland
| | - Jurate Panaviene
- University College Cork, INFANT Research Centre, Cork, Ireland
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland
| | - Eugene M Dempsey
- University College Cork, INFANT Research Centre, Cork, Ireland
- Department of Paediatrics and Child Health, University College Cork, Cork, Ireland
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2
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Zeng Y, Wang H, Zhang L, Tang J, Shi J, Xiao D, Qu Y, Mu D. The optimal choices of animal models of white matter injury. Rev Neurosci 2019; 30:245-259. [PMID: 30379639 DOI: 10.1515/revneuro-2018-0044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/16/2018] [Indexed: 12/25/2022]
Abstract
White matter injury, the most common neurological injury in preterm infants, is a major cause of chronic neurological morbidity, including cerebral palsy. Although there has been great progress in the study of the mechanism of white matter injury in newborn infants, its pathogenesis is not entirely clear, and further treatment approaches are required. Animal models are the basis of study in pathogenesis, treatment, and prognosis of white matter injury in preterm infants. Various species have been used to establish white matter injury models, including rodents, rabbits, sheep, and non-human primates. Small animal models allow cost-effective investigation of molecular and cellular mechanisms, while large animal models are particularly attractive for pathophysiological and clinical-translational studies. This review focuses on the features of commonly used white matter injury animal models, including their modelling methods, advantages, and limitations, and addresses some clinically relevant animal models that allow reproduction of the insults associated with clinical conditions that contribute to white matter injury in human infants.
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Affiliation(s)
- Yan Zeng
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China
| | - Huiqing Wang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China
| | - Li Zhang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China
| | - Jun Tang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China
| | - Jing Shi
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China
| | - Dongqiong Xiao
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China
| | - Yi Qu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China
| | - Dezhi Mu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, No. 20, section 3, Renmin South Road, Chengdu, Sichuan 610041, China.,Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects, Ministry of Education, Sichuan University, Chengdu 610041, China, Telephone: +86-28-85503226, Fax: +86-28-85559065
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3
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Badurdeen S, Roberts C, Blank D, Miller S, Stojanovska V, Davis P, Hooper S, Polglase G. Haemodynamic Instability and Brain Injury in Neonates Exposed to Hypoxia⁻Ischaemia. Brain Sci 2019; 9:E49. [PMID: 30818842 PMCID: PMC6468566 DOI: 10.3390/brainsci9030049] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/24/2019] [Accepted: 02/26/2019] [Indexed: 11/23/2022] Open
Abstract
Brain injury in the asphyxic newborn infant may be exacerbated by delayed restoration of cardiac output and oxygen delivery. With increasing severity of asphyxia, cerebral autoregulatory responses are compromised. Further brain injury may occur in association with high arterial pressures and cerebral blood flows following the restoration of cardiac output. Initial resuscitation aims to rapidly restore cardiac output and oxygenation whilst mitigating the impact of impaired cerebral autoregulation. Recent animal studies have indicated that the current standard practice of immediate umbilical cord clamping prior to resuscitation may exacerbate injury. Resuscitation prior to umbilical cord clamping confers several haemodynamic advantages. In particular, it retains the low-resistance placental circuit that mitigates the rebound hypertension and cerebrovascular injury. Prolonged cerebral hypoxia⁻ischaemia is likely to contribute to further perinatal brain injury, while, at the same time, tissue hyperoxia is associated with oxidative stress. Efforts to monitor and target cerebral flow and oxygen kinetics, for example, using near-infrared spectroscopy, are currently being evaluated and may facilitate development of novel resuscitation approaches.
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Affiliation(s)
- Shiraz Badurdeen
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
- Newborn Research Centre, The Royal Women's Hospital, Melbourne 3052, Australia.
| | - Calum Roberts
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Douglas Blank
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Suzanne Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Vanesa Stojanovska
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Peter Davis
- Newborn Research Centre, The Royal Women's Hospital, Melbourne 3052, Australia.
| | - Stuart Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Graeme Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
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4
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Rhee CJ, da Costa CS, Austin T, Brady KM, Czosnyka M, Lee JK. Neonatal cerebrovascular autoregulation. Pediatr Res 2018; 84:602-610. [PMID: 30196311 PMCID: PMC6422675 DOI: 10.1038/s41390-018-0141-6] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 06/04/2018] [Accepted: 07/27/2018] [Indexed: 12/12/2022]
Abstract
Cerebrovascular pressure autoregulation is the physiologic mechanism that holds cerebral blood flow (CBF) relatively constant across changes in cerebral perfusion pressure (CPP). Cerebral vasoreactivity refers to the vasoconstriction and vasodilation that occur during fluctuations in arterial blood pressure (ABP) to maintain autoregulation. These are vital protective mechanisms of the brain. Impairments in pressure autoregulation increase the risk of brain injury and persistent neurologic disability. Autoregulation may be impaired during various neonatal disease states including prematurity, hypoxic-ischemic encephalopathy (HIE), intraventricular hemorrhage, congenital cardiac disease, and infants requiring extracorporeal membrane oxygenation (ECMO). Because infants are exquisitely sensitive to changes in cerebral blood flow (CBF), both hypoperfusion and hyperperfusion can cause significant neurologic injury. We will review neonatal pressure autoregulation and autoregulation monitoring techniques with a focus on brain protection. Current clinical therapies have failed to fully prevent permanent brain injuries in neonates. Adjuvant treatments that support and optimize autoregulation may improve neurologic outcomes.
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Affiliation(s)
- Christopher J. Rhee
- Baylor College of Medicine, Texas Children’s Hospital, Department of Pediatrics, Section of Neonatology, Houston, TX, USA
| | | | - Topun Austin
- Neonatal Unit, Rosie Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Ken M. Brady
- Baylor College of Medicine, Texas Children’s Hospital, Department of Pediatrics, Critical Care Medicine and Anesthesiology, Houston, TX, USA
| | - Marek Czosnyka
- Department of Academic Neurosurgery, Addenbrooke’s Hospital, University of Cambridge, Cambridge, UK
| | - Jennifer K. Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
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5
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Polglase GR, Blank DA, Barton SK, Miller SL, Stojanovska V, Kluckow M, Gill AW, LaRosa D, Te Pas AB, Hooper SB. Physiologically based cord clamping stabilises cardiac output and reduces cerebrovascular injury in asphyxiated near-term lambs. Arch Dis Child Fetal Neonatal Ed 2018; 103:F530-F538. [PMID: 29191812 DOI: 10.1136/archdischild-2017-313657] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/23/2017] [Accepted: 11/05/2017] [Indexed: 11/03/2022]
Abstract
BACKGROUND Physiologically based cord clamping (PBCC) has advantages over immediate cord clamping (ICC) during preterm delivery, but its efficacy in asphyxiated infants is not known. We investigated the physiology of PBCC following perinatal asphyxia in near-term lambs. METHODS Near-term sheep fetuses (139±2 (SD) days' gestation) were instrumented to measure umbilical, carotid, pulmonary and femoral arterial flows and pressures. Systemic and cerebral oxygenation was recorded using pulse oximetry and near-infrared spectroscopy, respectively. Fetal asphyxia was induced until mean blood pressure reached ~20 mm Hg, where lambs underwent ICC and initiation of ventilation (n=7), or ventilation for 15 min prior to umbilical cord clamping (PBCC; n=8). Cardiovascular parameters were measured and white and grey matter microvascular integrity assessed using qRT-PCR and immunohistochemistry. RESULTS PBCC restored oxygenation and cardiac output at the same rate and in a similar fashion to lambs resuscitated following ICC. However, ICC lambs had a rapid and marked overshoot in mean systemic arterial blood pressure from 1 to 10 min after ventilation onset, which was largely absent in PBCC lambs. ICC lambs had increased cerebrovascular injury, as indicated by reduced expression of blood-brain barrier proteins and increased cerebrovascular protein leakage in the subcortical white matter (by 86%) and grey matter (by 47%). CONCLUSION PBCC restored cardiac output and oxygenation in an identical time frame as ICC, but greatly mitigated the postasphyxia rebound hypertension measured in ICC lambs. This likely protected the asphyxiated brain from cerebrovascular injury. PBCC may be a more suitable option for the resuscitation of the asphyxiated newborn compared with the current standard of ICC.
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Affiliation(s)
- Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Douglas A Blank
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, UK
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, UK
| | - Vanesa Stojanovska
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Martin Kluckow
- Department of Neonatology, Royal North Shore Hospital and University of Sydney, Sydney, New South Wales, Australia
| | - Andrew W Gill
- Centre for Neonatal Research and Education, The University of Western Australia, Subiaco, Western Australia, Australia
| | - Domenic LaRosa
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Arjan B Te Pas
- Division of Neonatology, Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
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6
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Rhee CJ, Kibler KK, Easley RB, Andropoulos DB, Czosnyka M, Smielewski P, Varsos GV, Brady KM, Rusin CG, Fraser CD, Gauss CH, Williams DK, Kaiser JR. The Diastolic Closing Margin Is Associated with Intraventricular Hemorrhage in Premature Infants. ACTA NEUROCHIRURGICA. SUPPLEMENT 2017; 122:147-50. [PMID: 27165896 DOI: 10.1007/978-3-319-22533-3_30] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Premature infants are at an increased risk of intraventricular hemorrhage (IVH). The roles of hypotension and hyperemia are still debated. Critical closing pressure (CrCP) is the arterial blood pressure (ABP) at which cerebral blood flow (CBF) ceases. When diastolic ABP is equal to CrCP, CBF occurs only during systole. The difference between diastolic ABP and CrCP is the diastolic closing margin (DCM). We hypothesized that a low DCM was associated with IVH. One hundred eighty-six premature infants, with a gestational age (GA) range of 23-33 weeks, were monitored with umbilical artery catheters and transcranial Doppler insonation of middle cerebral artery flow velocity for 1-h sessions over the first week of life. CrCP was calculated linearly and using an impedance model. A multivariate generalized linear regression model was used to determine associations with severe IVH (grades 3-4). An elevated DCM by either method was associated with IVH (p < 0.0001 for the linear method; p < 0.001 for the impedance model). Lower 5-min Apgar scores, elevated mean CBF velocity, and lower mean ABP were also associated with IVH (p < 0.0001). Elevated DCM, not low DCM, was associated with severe IVH in this cohort.
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Affiliation(s)
- Christopher J Rhee
- Department of Pediatrics, Section of Neonatology, Texas Children's Hospital/Baylor College of Medicine, 6621 Fannin Street, W6-104, Houston, TX, USA.
| | - Kathleen K Kibler
- Departments of Anesthesiology, Critical Care Medicine, and Pediatrics, Texas Children's Hospital/Baylor College of Medicine, Houston, TX, USA
| | - R Blaine Easley
- Departments of Anesthesiology, Critical Care Medicine, and Pediatrics, Texas Children's Hospital/Baylor College of Medicine, Houston, TX, USA
| | - Dean B Andropoulos
- Departments of Anesthesiology, Critical Care Medicine, and Pediatrics, Texas Children's Hospital/Baylor College of Medicine, Houston, TX, USA
| | - Marek Czosnyka
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Peter Smielewski
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Georgios V Varsos
- Department of Academic Neurosurgery, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Ken M Brady
- Departments of Anesthesiology, Critical Care Medicine, and Pediatrics, Texas Children's Hospital/Baylor College of Medicine, Houston, TX, USA
| | - Craig G Rusin
- Department of Cardiology, Texas Children's Hospital/Baylor College of Medicine, Houston, TX, USA
| | - Charles D Fraser
- University of Texas at Houston School of Medicine, Houston, TX, USA
| | - C Heath Gauss
- Department of Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - D Keith Williams
- Department of Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Jeffrey R Kaiser
- Department of Pediatrics, Section of Neonatology, Texas Children's Hospital/Baylor College of Medicine, 6621 Fannin Street, W6-104, Houston, TX, USA
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7
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Ong T, Sobotka KS, Siew ML, Crossley KJ, van Vonderen JJ, Polglase GR, Hooper SB. The cardiovascular response to birth asphyxia is altered by the surrounding environment. Arch Dis Child Fetal Neonatal Ed 2016; 101:F540-F545. [PMID: 27059073 DOI: 10.1136/archdischild-2015-309596] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 03/10/2016] [Accepted: 03/14/2016] [Indexed: 11/04/2022]
Abstract
BACKGROUND A sustained bradycardia is used as a major indicator of severe perinatal asphyxia. However, lambs asphyxiated ex utero do not exhibit the same bradycardic response as lambs asphyxiated in utero. It is possible that the local in utero environment may influence the initial cardiovascular response to asphyxia. We assessed the effect of facial immersion in water on the cardiovascular response to birth asphyxia. METHODS Pregnant ewes (138±1 days gestation) were anaesthetised and fetuses were exteriorised and instrumented for measurement of cardiopulmonary haemodynamics. The lamb's head either remained in air (n=5) or was placed in water that was either warm (40±1°C; n=5) or at room temperature (21±1°C; n=5) before the umbilical cord was clamped to induce asphyxia. RESULTS Heart rate after bradycardia onset was reduced in lambs asphyxiated with their head in cool water (-34±2%) and warm water (-25±4%) compared with those in air (-11±5%; p<0.05). Similarly, the decrease in blood pressure was faster in lambs with water around the face compared with those in air. From 75 s after asphyxia onset, mean and end-diastolic carotid blood flow was higher in the group asphyxiated in air (25±4 mL/kg/min), compared with the groups in water (13±3 mL/kg/min, warm water; 16±2 mL/kg/min, cool water; p<0.05). CONCLUSIONS The cardiovascular response to birth asphyxia is altered by the presence and temperature of water surrounding the head. The previous understanding of the vagally mediated bradycardia associated with birth asphyxia may include components of the diving reflex.
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Affiliation(s)
- Tracey Ong
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Kristina S Sobotka
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Melissa L Siew
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Kelly J Crossley
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | | | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
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8
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Intubation Attempts Increase the Risk for Severe Intraventricular Hemorrhage in Preterm Infants-A Retrospective Cohort Study. J Pediatr 2016; 177:108-113. [PMID: 27470688 DOI: 10.1016/j.jpeds.2016.06.051] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 05/06/2016] [Accepted: 06/14/2016] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To evaluate whether neonates exposed to multiple intubation attempts within the first 4 days after birth have an increased incidence of intraventricular hemorrhage (IVH). STUDY DESIGN This is a retrospective cohort study of infants intubated during the first 4 days after birth. Infants had birth weights (BWs) less than 1500 g and were admitted to the neonatal intensive care unit (NICU) at the University of California, San Diego, between January 1, 2005, and July 30, 2009. A subgroup analysis was done for infants with BW less than 750 g. RESULTS A total of 308 infants with BW <1500 g, including 102 with a BW <750 g, were intubated within the first 4 days of life. The number of intubation attempts was significantly greater in infants with a BW <750 g who had severe IVH compared with those with mild or no IVH (OR 1.395, 95% CI 1.090-1.786, P = .008). For infants with BW <1500 g, the number of intubation attempts in the delivery room was significantly greater for infants with severe IVH (OR 1.317, 95% CI 1.052-1.649, P = .016). CONCLUSION Increased intubation attempts were associated with increased incidence of severe IVH in infants with BW less than 750 g and in infants less than 1500 g who were intubated only in the delivery room. Prospective studies are needed to further evaluate the relationship between intubation attempts and severe IVH.
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9
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Te Pas AB, Sobotka K, Hooper SB. Novel Approaches to Neonatal Resuscitation and the Impact on Birth Asphyxia. Clin Perinatol 2016; 43:455-67. [PMID: 27524447 DOI: 10.1016/j.clp.2016.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Historically, recommendations for neonatal resuscitation were largely based on dogma, but there is renewed interest in performing resuscitation studies at birth. The emphasis for resuscitation following birth asphyxia is administering effective ventilation, as adequate lung aeration leads not only to an increase in oxygenation but also increased pulmonary blood flow and heart rate. To aerate the lung, an initial sustained inflation can increase heart rate, oxygenation, and blood pressure recovery much faster when compared with standard ventilation. Hyperoxia should be avoided, and extra oxygen given to restore cardiac function and spontaneous breathing should be titrated based on oxygen saturations.
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Affiliation(s)
- Arjan B Te Pas
- Division of Neonatology, Department of Pediatrics, Leiden University Medical Centre, J6-S, PO Box 9600, Leiden 2300 RC, The Netherlands.
| | - Kristina Sobotka
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Box 432, Göteborg 405 30, Sweden
| | - Stuart B Hooper
- The Ritchie Centre, MIMR-PHI Institute of Medical Research, Monash Institute of Medical Research, Monash University, 27-31 Wright Street, Clayton, Melbourne, Victoria 3168, Australia
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10
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Lamberska T, Luksova M, Smisek J, Vankova J, Plavka R. Premature infants born at <25 weeks of gestation may be compromised by currently recommended resuscitation techniques. Acta Paediatr 2016; 105:e142-50. [PMID: 26341533 DOI: 10.1111/apa.13178] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 03/29/2015] [Accepted: 09/01/2015] [Indexed: 01/07/2023]
Abstract
AIM Standard resuscitation guidelines are based on data from a range of gestational ages. We sought to evaluate the effectiveness of our delivery room resuscitation protocol across a range of gestational ages in preterm infants born at <29 weeks. METHODS We performed an observational study of prospectively collected video recordings of 73 preterm infants. The percentage of bradycardic patients, time to reach target oxygen saturation and the extent of all interventions were compared between three gestational age groups: 22-24 weeks (n = 22), 25-26 weeks (n = 27) and 27-28 weeks (n = 24). RESULTS Although the same resuscitation protocol was followed for all infants, bradycardic infants born <25 weeks responded poorly and required significantly longer to reach oxygen saturation targets of >70%, >80% and >90% (p < 0.03). They required significantly more interventions and had higher rate of death (p < 0.05) and severe intraventricular haemorrhage (p < 0.03). Significantly lower heart rate and oxygen saturation values were found in infants with intraventricular haemorrhage. CONCLUSION Current recommendations for resuscitation may fail to achieve timely lung aeration in infants born at the borderline of viability, leading to higher mortality and morbidity. Sustained inflation and delayed cord clamping may be effective alternatives.
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Affiliation(s)
- Tereza Lamberska
- Division of Neonatology; Department of Obstetrics and Gynaecology; General Faculty Hospital and 1st Faculty of Medicine; Charles University in Prague; Prague Czech Republic
| | - Marketa Luksova
- Division of Neonatology; Department of Obstetrics and Gynaecology; General Faculty Hospital and 1st Faculty of Medicine; Charles University in Prague; Prague Czech Republic
| | - Jan Smisek
- Division of Neonatology; Department of Obstetrics and Gynaecology; General Faculty Hospital and 1st Faculty of Medicine; Charles University in Prague; Prague Czech Republic
| | - Jana Vankova
- Division of Neonatology; Department of Obstetrics and Gynaecology; General Faculty Hospital and 1st Faculty of Medicine; Charles University in Prague; Prague Czech Republic
| | - Richard Plavka
- Division of Neonatology; Department of Obstetrics and Gynaecology; General Faculty Hospital and 1st Faculty of Medicine; Charles University in Prague; Prague Czech Republic
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11
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Sobotka KS, Hooper SB, Crossley KJ, Ong T, Schmölzer GM, Barton SK, McDougall ARA, Miller SL, Tolcos M, Klingenberg C, Polglase GR. Single Sustained Inflation followed by Ventilation Leads to Rapid Cardiorespiratory Recovery but Causes Cerebral Vascular Leakage in Asphyxiated Near-Term Lambs. PLoS One 2016; 11:e0146574. [PMID: 26765258 PMCID: PMC4713062 DOI: 10.1371/journal.pone.0146574] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/18/2015] [Indexed: 11/19/2022] Open
Abstract
Background A sustained inflation (SI) rapidly restores cardiac function in asphyxic, bradycardic newborns but its effects on cerebral haemodynamics and brain injury are unknown. We determined the effect of different SI strategies on carotid blood flow (CaBF) and cerebral vascular integrity in asphyxiated near-term lambs. Methods Lambs were instrumented and delivered at 139 ± 2 d gestation and asphyxia was induced by delaying ventilation onset. Lambs were randomised to receive 5 consecutive 3 s SI (multiple SI; n = 6), a single 30 s SI (single SI; n = 6) or conventional ventilation (no SI; n = 6). Ventilation continued for 30 min in all lambs while CaBF and respiratory function parameters were recorded. Brains were assessed for gross histopathology and vascular leakage. Results CaBF increased more rapidly and to a greater extent during a single SI (p = 0.01), which then decreased below both other groups by 10 min, due to a higher cerebral oxygen delivery (p = 0.01). Blood brain barrier disruption was increased in single SI lambs as indicated by increased numbers of blood vessel profiles with plasma protein extravasation (p = 0.001) in the cerebral cortex. There were no differences in CaBF or cerebral oxygen delivery between the multiple SI and no SI lambs. Conclusions Ventilation with an initial single 30 s SI improves circulatory recovery, but is associated with greater disruption of blood brain barrier function, which may exacerbate brain injury suffered by asphyxiated newborns. This injury may occur as a direct result of the initial SI or to the higher tidal volumes delivered during subsequent ventilation.
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Affiliation(s)
- Kristina S. Sobotka
- The Ritchie Centre, Monash University, Melbourne, Australia
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- * E-mail:
| | - Stuart B. Hooper
- The Ritchie Centre, Monash University, Melbourne, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Kelly J. Crossley
- The Ritchie Centre, Monash University, Melbourne, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Tracey Ong
- The Ritchie Centre, Monash University, Melbourne, Australia
| | - Georg M. Schmölzer
- Department of Pediatrics, Medical University, Graz, Austria
- Centre for the Studies of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Edmonton, Canada
- Department of Pediatrics, University of Alberta, Edmonton, Canada
| | | | | | - Suzie L. Miller
- The Ritchie Centre, Monash University, Melbourne, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Mary Tolcos
- The Ritchie Centre, Monash University, Melbourne, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Claus Klingenberg
- Department of Paediatrics, University Hospital of North Norway, Tromsø, Norway
- Paediatric Research Group, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
| | - Graeme R. Polglase
- The Ritchie Centre, Monash University, Melbourne, Australia
- Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
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Barton SK, McDougall ARA, Melville JM, Moss TJM, Zahra VA, Lim T, Crossley KJ, Polglase GR, Tolcos M. Differential short-term regional effects of early high dose erythropoietin on white matter in preterm lambs after mechanical ventilation. J Physiol 2015; 594:1437-49. [PMID: 26332509 DOI: 10.1113/jp271376] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 08/13/2015] [Indexed: 11/08/2022] Open
Abstract
Inadvertently injurious ventilation of preterm neonates in the delivery room can cause cerebral white matter (WM) inflammation and injury. We investigated the impact of an early high dose of recombinant human erythropoietin (EPO) on ventilation-induced WM changes in preterm lambs. Injurious ventilation, targeting a V(T) of 15 ml kg(-1) with no positive end-expiratory pressure, was initiated for 15 min in preterm lambs (0.85 gestation). Conventional ventilation was continued for a further 105 min. Lambs received either 5000 IU kg(-1) of EPO (EPREX®; Vent+EPO; n = 6) or vehicle (Vent; n = 8) via an umbilical vein at 4 ± 2 min. Markers of WM injury and inflammation were assessed using quantitative real-time PCR (qPCR) and immunohistochemistry and compared to a group of unventilated controls (UVC; n = 4). In Vent+EPO lambs compared to Vent lambs: (i) interleukin (IL)-1β and IL-6 mRNA levels in the periventricular WM and IL-8 mRNA levels in the subcortical WM were higher (P < 0.05 for all); (ii) the density of microglia within the aggregations was not different in the periventricular WM and was lower in the subcortical WM (P = 0.001); (iii) the density of astrocytes was lower in the subcortical WM (P = 0.002); (iv) occludin and claudin-1 mRNA levels were higher in the periventricular WM (P < 0.02 for all) and (vi) the number of blood vessels with protein extravasation was lower (P < 0.05). Recombinant human EPO had variable regional effects within the WM when administered during injurious ventilation. The adverse short-term outcomes discourage the use of early high dose EPO administration in preterm ventilated babies.
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Affiliation(s)
- Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Annie R A McDougall
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3168, Australia
| | - Jacqueline M Melville
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Timothy J M Moss
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, 3168, Australia
| | - Valerie A Zahra
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Tammy Lim
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Kelly J Crossley
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, 3168, Australia
| | - Mary Tolcos
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, 3168, Australia
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13
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Effects of chest compressions on cardiovascular and cerebral hemodynamics in asphyxiated near-term lambs. Pediatr Res 2015; 78:395-400. [PMID: 26086644 DOI: 10.1038/pr.2015.117] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 03/16/2015] [Indexed: 11/08/2022]
Abstract
BACKGROUND Chest compressions (CC) and adrenaline administration are recommended in asphyxiated newborns with persistent bradycardia despite effective ventilation. The effects of CC on cerebral blood flow in newborns at birth are unknown. Our aim was to determine the effects of CC, with or without adrenaline administration, on the return of spontaneous circulation, carotid blood flow (CBF), and carotid arterial pressure (CAP) in asphyxiated near-term lambs. METHODS Asphyxia was induced in near-term lambs by clamping the umbilical cord and delaying ventilation onset until spontaneous circulation ceased. Lambs were then resuscitated by positive pressure ventilation along with CC followed by adrenaline administration. CAP and CBF were continuously recorded. RESULTS Mean CAP did not increase significantly during CC and only increased following adrenaline administration. CC did not increase mean CBF but increased CBF amplitude due to increased peak flow and the onset of retrograde flow during diastole. Adrenaline increased mean CBF from 1 ± 2 to 15 ± 5 ml/kg/min and abolished retrograde diastolic CBF, leading to the return in spontaneous circulation. CONCLUSION We conclude that CC with adrenaline administration was required to increase CBF and restore spontaneous circulation in asphyxiated lambs. Low CBF and retrograde diastolic CBF during CC indicate hypoperfusion to the brain.
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14
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Sobotka KS, Ong T, Polglase GR, Crossley KJ, Moss TJM, Hooper SB. The effect of oxygen content during an initial sustained inflation on heart rate in asphyxiated near-term lambs. Arch Dis Child Fetal Neonatal Ed 2015; 100:F337-43. [PMID: 25922189 DOI: 10.1136/archdischild-2014-307319] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 03/22/2015] [Indexed: 11/03/2022]
Abstract
OBJECTIVE At birth, an initial sustained inflation (SI) uniformly aerates the lungs, increases arterial oxygenation and rapidly improves circulatory recovery in asphyxiated newborns. We hypothesised that lung aeration, in the absence of an increase in arterial oxygenation, can increase heart rate (HR) in asphyxiated near-term lambs. INTERVENTIONS Lambs were delivered and instrumented at 139±2 days of gestation. Asphyxia was induced by umbilical cord clamping and then delaying the onset of ventilation until mean carotid arterial pressures (CAPs) had decreased <20 mm Hg. Lambs then received a single 30-s SI using nitrogen (N2; n=6), 5% oxygen (O2; n=6), 21% O2 (n=6) or 100% O2 (n=6) followed by ventilation in air for 30 min. MAIN OUTCOME MEASURES HR, CAP and pulmonary blood flow (PBF) were continuously recorded. RESULTS HR and PBF increased more quickly in lambs resuscitated with 100% and 21% O2 than with 5% O2 or N2. HR and PBF recovery in the 5% O2 group was delayed relative to all other oxygen SI groups. HR in 5%, 21% and 100% O2 groups reached 100 bpm before the SI was complete. HR and PBF in the N2 group did not increase until 10 s after the SI was completed and ventilation was initiated with air. CAP tended to increase quicker in all O2 groups than in N2 group. CONCLUSIONS Oxygen content during an SI is important for circulatory recovery in asphyxiated lambs. This increase in HR is likely driven by the increase in PBF and venous return to the heart.
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Affiliation(s)
- K S Sobotka
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Australia
| | - T Ong
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Australia
| | - G R Polglase
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Australia Department of Obstetrics and Gynaecology, Monash University, Clayton, Australia
| | - K J Crossley
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Australia
| | - T J M Moss
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Australia Department of Obstetrics and Gynaecology, Monash University, Clayton, Australia
| | - S B Hooper
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Australia Department of Obstetrics and Gynaecology, Monash University, Clayton, Australia
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15
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Ventilation onset prior to umbilical cord clamping (physiological-based cord clamping) improves systemic and cerebral oxygenation in preterm lambs. PLoS One 2015; 10:e0117504. [PMID: 25689406 PMCID: PMC4331493 DOI: 10.1371/journal.pone.0117504] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 12/26/2014] [Indexed: 11/23/2022] Open
Abstract
Background As measurement of arterial oxygen saturation (SpO2) is common in the delivery room, target SpO2 ranges allow clinicians to titrate oxygen therapy for preterm infants in order to achieve saturation levels similar to those seen in normal term infants in the first minutes of life. However, the influence of the onset of ventilation and the timing of cord clamping on systemic and cerebral oxygenation is not known. Aim We investigated whether the initiation of ventilation, prior to, or after umbilical cord clamping, altered systemic and cerebral oxygenation in preterm lambs. Methods Systemic and cerebral blood-flows, pressures and peripheral SpO2 and regional cerebral tissue oxygenation (SctO2) were measured continuously in apnoeic preterm lambs (126±1 day gestation). Positive pressure ventilation was initiated either 1) prior to umbilical cord clamping, or 2) after umbilical cord clamping. Lambs were monitored intensively prior to intervention, and for 10 minutes following umbilical cord clamping. Results Clamping the umbilical cord prior to ventilation resulted in a rapid decrease in SpO2 and SctO2, and an increase in arterial pressure, cerebral blood flow and cerebral oxygen extraction. Ventilation restored oxygenation and haemodynamics by 5–6 minutes. No such disturbances in peripheral or cerebral oxygenation and haemodynamics were observed when ventilation was initiated prior to cord clamping. Conclusion The establishment of ventilation prior to umbilical cord clamping facilitated a smooth transition to systemic and cerebral oxygenation following birth. SpO2 nomograms may need to be re-evaluated to reflect physiological management of preterm infants in the delivery room.
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16
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van den Broek MPH, van Straaten HLM, Huitema ADR, Egberts T, Toet MC, de Vries LS, Rademaker K, Groenendaal F. Anticonvulsant effectiveness and hemodynamic safety of midazolam in full-term infants treated with hypothermia. Neonatology 2015; 107:150-6. [PMID: 25572061 DOI: 10.1159/000368180] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 09/03/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND Midazolam is used as an anticonvulsant in neonatology, including newborns with perinatal asphyxia treated with hypothermia. Hypothermia may affect the safety and effectiveness of midazolam in these patients. OBJECTIVES The objective was to evaluate the anticonvulsant effectiveness and hemodynamic safety of midazolam in hypothermic newborns and to provide dosing guidance. METHODS Hypothermic newborns with perinatal asphyxia and treated with midazolam were included. Effectiveness was studied using continuous amplitude-integrated electroencephalography. Hemodynamic safety was assessed using pharmacokinetic-pharmacodynamic modeling with plasma samples and blood pressure recordings (mean arterial blood pressure) under hypothermia. RESULTS No effect of therapeutic hypothermia on pharmacokinetics could be identified. Add-on seizure control with midazolam was limited (23% seizure control). An inverse relationship between the midazolam plasma concentration and mean arterial blood pressure could be identified. At least one hypotensive episode was experienced in 64%. The concomitant use of inotropes decreased midazolam clearance by 33%. CONCLUSIONS Under therapeutic hypothermia, midazolam has limited add-on clinical anticonvulsant effectiveness after phenobarbital administration. Due to occurrence of hypotension requiring inotropic support, midazolam is less suitable as a second-line anticonvulsant drug under hypothermia.
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17
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Rhee CJ, Fraser CD, Kibler K, Easley RB, Andropoulos DB, Czosnyka M, Varsos GV, Smielewski P, Rusin CG, Brady KM, Kaiser JR. The ontogeny of cerebrovascular pressure autoregulation in premature infants. J Perinatol 2014; 34:926-31. [PMID: 25010225 PMCID: PMC4383263 DOI: 10.1038/jp.2014.122] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 04/01/2014] [Accepted: 05/16/2014] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To quantify cerebrovascular autoregulation as a function of gestational age (GA) and across the phases of the cardiac cycle. STUDY DESIGN The present study is a hypothesis-generating re-analysis of previously published data. Premature infants (n=179) with a GA range of 23 to 33 weeks were monitored with umbilical artery catheters and transcranial Doppler insonation of the middle cerebral artery for 1-h sessions over the first week of life. Autoregulation was quantified by three methods, as a moving correlation coefficient between: (1) systolic arterial blood pressure (ABP) and systolic cerebral blood flow (CBF) velocity (Sx); (2) mean ABP and mean CBF velocity (Mx); and (3) diastolic ABP and diastolic CBF velocity (Dx). Comparisons of individual and cohort cerebrovascular pressure autoregulation were made across GA for each aspect of the cardiac cycle. RESULTS Systolic, mean and diastolic ABP increased with GA (r=0.3, 0.4 and 0.4; P<0.0001). Systolic CBF velocity was pressure-passive in infants with the lowest GA, and Sx decreased with advancing GA (r=-0.3; P<0.001), indicating increased capacity for cerebral autoregulation during systole during development. By contrast, Dx was elevated, indicating dysautoregulation, in all subjects and showed minimal change with advancing GA (r=-0.06; P=0.05). Multivariate analysis confirmed that both GA (P<0.001) and 'effective cerebral perfusion pressure' (ABP minus critical closing pressure (CrCP); P<0.01) were associated with Sx. CONCLUSION Premature infants have low and usually pressure-passive diastolic CBF velocity. By contrast, the regulation of systolic CBF velocity by pressure autoregulation developed in this cohort between 23 and 33 weeks GA. Elevated effective cerebral perfusion pressure derived from the CrCP was associated with dysautoregulation.
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Affiliation(s)
- Christopher J. Rhee
- Department of Pediatrics, Section of Neonatology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX, USA
| | | | - Kathleen Kibler
- Departments of Pediatrics and Anesthesiology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Ronald B. Easley
- Departments of Pediatrics and Anesthesiology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Dean B. Andropoulos
- Departments of Pediatrics and Anesthesiology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Marek Czosnyka
- Division of Neurosurgery, Addenbrooke’s Hospital, Cambridge University, Cambridge, England
| | - Georgios V. Varsos
- Division of Neurosurgery, Addenbrooke’s Hospital, Cambridge University, Cambridge, England
| | - Peter Smielewski
- Division of Neurosurgery, Addenbrooke’s Hospital, Cambridge University, Cambridge, England
| | - Craig G. Rusin
- Department of Cardiology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Ken M. Brady
- Departments of Pediatrics and Anesthesiology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX, USA
| | - Jeffrey R. Kaiser
- Departments of Pediatrics and Obstetrics and Gynecology, Section of Neonatology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX, USA
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Polglase GR, Miller SL, Barton SK, Kluckow M, Gill AW, Hooper SB, Tolcos M. Respiratory support for premature neonates in the delivery room: effects on cardiovascular function and the development of brain injury. Pediatr Res 2014; 75:682-8. [PMID: 24614803 DOI: 10.1038/pr.2014.40] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 12/16/2013] [Indexed: 02/02/2023]
Abstract
The transition to newborn life in preterm infants is complicated by immature cardiovascular and respiratory systems. Consequently, preterm infants often require respiratory support immediately after birth. Although aeration of the lung underpins the circulatory transition at birth, positive pressure ventilation can adversely affect cardiorespiratory function during this vulnerable period, reducing pulmonary blood flow and left ventricular output. Furthermore, pulmonary volutrauma is known to initiate pulmonary inflammatory responses, resulting in remote systemic involvement. This review focuses on the downstream consequences of positive pressure ventilation, in particular, interactions between cardiovascular output and the initiation of a systemic inflammatory cascade, on the immature brain. Recent studies have highlighted that positive pressure ventilation strategies are precursors of cerebral injury, probably mediated through cerebral blood flow instability. The presence of, or initiation of, an inflammatory cascade accentuates adverse cerebral blood flow, in addition to being a direct source of brain injury. Importantly, the degree of brain injury is dependent on the nature of the initial ventilation strategy used.
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Affiliation(s)
- Graeme R Polglase
- 1] The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia [2] Department of Obstetrics and Gynecology, Monash University, Clayton, Victoria, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
| | - Samantha K Barton
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
| | - Martin Kluckow
- Department of Neonatalogy, Royal North Shore Hospital, University of Sydney, Sydney, New South Wales, Australia
| | - Andrew W Gill
- Centre for Neonatal Research and Education, The University of Western Australia, Western Australia, Australia
| | - Stuart B Hooper
- 1] The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia [2] Department of Obstetrics and Gynecology, Monash University, Clayton, Victoria, Australia
| | - Mary Tolcos
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
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Duerden EG, Brown-Lum M, Chau V, Poskitt KJ, Grunau RE, Synnes A, Miller SP. Resuscitation intensity at birth is associated with changes in brain metabolic development in preterm neonates. Neuroradiology 2013; 55 Suppl 2:47-54. [PMID: 23921419 DOI: 10.1007/s00234-013-1243-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 07/10/2013] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Intensive resuscitation at birth has been linked to intraventricular haemorrhage (IVH) in the preterm neonate. However, the impact of less intensive resuscitation on more subtle alterations in brain metabolic development is largely unknown. Our objective was to determine the relationship between the intensity of neonatal resuscitation following preterm birth on brain metabolic development. METHODS One hundred thirty-three very preterm-born neonates (median gestational age [GA] 27 ± 2 weeks) underwent MR spectroscopic imaging early in life (median postmenstrual age 32 weeks) and again at term-equivalent age (median 40 weeks). Severity of white matter injury, IVH and cerebellar haemorrhage on magnetic resonance imaging were scored. Ratios of N-acetylaspartate (NAA) and lactate to choline (Cho) were calculated in eight regions of interest and were assessed in relation to intensiveness of resuscitation strategy (bag and mask, continuous positive airway pressure [CPAP], intubation, cardiopulmonary resuscitation [CPR]). RESULTS Within the first hour of life, 14 newborns had no intervention, 3 received bag and mask, 30 had CPAP, 79 were intubated and 7 had CPR. Resuscitated infants were more likely to have IVH (p = 0.02). More intensive resuscitation was associated with decreased NAA/Cho maturation (p < 0.001, adjusting for birth GA). Metabolic development was similar in neonates requiring CPAP in comparison to those receiving no intervention. The change in lactate/Cho did not differ across resuscitation categories (p = 0.8). CONCLUSIONS Intensity of resuscitation at birth is related to changes in metabolic brain development from early in life to term-equivalent age. Results suggest that preventing the need for intensive neonatal resuscitation may provide an opportunity to improve brain development in preterm neonates.
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Affiliation(s)
- Emma G Duerden
- Department of Paediatrics, The Hospital for Sick Children and the University of Toronto, Toronto, ON, Canada
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Galinsky R, Moss TJM, Polglase GR, Hooper SB. Intrauterine inflammation alters cardiopulmonary but not cerebral hemodynamics during open endotracheal tube suction in preterm lambs. Pediatr Res 2013; 74:48-53. [PMID: 23618910 DOI: 10.1038/pr.2013.70] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 02/28/2013] [Indexed: 11/09/2022]
Abstract
BACKGROUND Intrauterine inflammation adversely affects cardiopulmonary, systemic, and cerebral hemodynamics in preterm neonates, but its impact on responses to endotracheal tube (ETT) suction, known to affect hemodynamics, is unknown. We hypothesized that intrauterine inflammation would alter the cardiopulmonary and cerebral hemodynamic response to open ETT suction in preterm lambs. METHODS Chronically instrumented fetuses received intra-amniotic lipopolysaccharide (LPS; to induce intrauterine inflammation) or saline at 118 d of gestation (term ~147 d). At 125 d of gestation, lambs were delivered and mechanically ventilated. Open ETT suction was performed 30 min after delivery. Pulmonary and cerebral arterial pressures and flows were recorded continuously. RESULTS Intrauterine inflammation reduced pulmonary blood flow (PBF) and increased pulmonary vascular resistance (PVR) after preterm birth. PBF and left-ventricular output (LVO) increased during and immediately after ETT suction in both groups, but the values were higher in LPS-exposed lambs. Preductal oxygenation significantly decreased during ETT suction but to a greater extent in LPS-exposed lambs. Cerebral blood flow and systemic arterial pressure were increased by open ETT suction similarly in the two groups. CONCLUSION Intrauterine inflammation exacerbates the neonatal hemodynamic response to open ETT suction.
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Affiliation(s)
- Robert Galinsky
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Melbourne, Australia.
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21
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Abstract
PURPOSE OF REVIEW A brief delay in clamping the umbilical cord after birth offers health benefits to the newborn, with no adverse effects to the mother or her infant. Yet, in most obstetric practice, the cord is clamped soon after birth. A summary of the current evidence on delayed cord clamping and some reasons for the disconnect between the evidence and practice are discussed here, along with the recommendations from professional organizations and societies about this practice. RECENT FINDINGS In term infants, umbilical cord clamping between 30 and 180 s after birth results in higher concentrations of hemoglobin and hematocrit during the neonatal period, and increased serum ferritin levels and a lower incidence of iron-deficiency anemia at 4-6 months of age. These are important benefits for children in low and middle income countries where iron-deficiency anemia is highly prevalent. In preterm infants, delayed cord clamping for at least 30 s increases the concentrations of hemoglobin and hematocrit, improves mean systemic blood pressure, urine output, and cardiac function, and decreases the need for vasopressors and blood transfusions during the neonatal period. It also decreases the prevalence of necrotizing enterocolitis, sepsis, and intraventricular hemorrhage (all grades). Milking of the unclamped umbilical cord toward the infant soon after birth also has similar beneficial effects. In some studies, more infants in the delayed cord clamping groups required phototherapy for jaundice. SUMMARY Many professional organizations, societies, and experts recommend at least a 30-s delay before clamping the umbilical cord, especially after preterm births. The value of this practice for term births in resource-rich settings has not been evaluated.
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Bhatt S, Alison BJ, Wallace EM, Crossley KJ, Gill AW, Kluckow M, te Pas AB, Morley CJ, Polglase GR, Hooper SB. Delaying cord clamping until ventilation onset improves cardiovascular function at birth in preterm lambs. J Physiol 2013; 591:2113-26. [PMID: 23401615 DOI: 10.1113/jphysiol.2012.250084] [Citation(s) in RCA: 299] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Delayed cord clamping improves circulatory stability in preterm infants at birth, but the underlying physiology is unclear. We investigated the effects of umbilical cord clamping, before and after ventilation onset, on cardiovascular function at birth. Prenatal surgery was performed on lambs (123 days) to implant catheters into the pulmonary and carotid arteries and probes to measure pulmonary (PBF), carotid (CaBF) and ductus arteriosus blood flows. Lambs were delivered at 126 ± 1 days and: (1) the umbilical cord was clamped at delivery and ventilation was delayed for about 2 min (Clamp 1st; n = 6), and (2) umbilical cord clamping was delayed for 3-4 min, until after ventilation was established (Vent 1st; n = 6). All lambs were subsequently ventilated for 30 min. In Clamp 1st lambs, cord clamping rapidly (within four heartbeats), but transiently, increased pulmonary and carotid arterial pressures (by ∼30%) and CaBF (from 30.2 ± 5.6 to 40.1 ± 4.6 ml min(-1) kg(-1)), which then decreased again within 30-60 s. Following ventilation onset, these parameters rapidly increased again. In Clamp 1st lambs, cord clamping reduced heart rate (by ∼40%) and right ventricular output (RVO; from 114.6 ± 14.4 to 38.8 ± 9.7 ml min(-1) kg(-1)), which were restored by ventilation. In Vent 1st lambs, cord clamping reduced RVO from 153.5 ± 3.8 to 119.2 ± 10.6 ml min(-1) kg(-1), did not affect heart rates and resulted in stable blood flows and pressures during transition. Delaying cord clamping for 3-4 min until after ventilation is established improves cardiovascular function by increasing pulmonary blood flow before the cord is clamped. As a result, cardiac output remains stable, leading to a smoother cardiovascular transition throughout the early newborn period.
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Affiliation(s)
- Sasmira Bhatt
- Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia
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Polglase GR, Miller SL, Barton SK, Baburamani AA, Wong FY, Aridas JDS, Gill AW, Moss TJM, Tolcos M, Kluckow M, Hooper SB. Initiation of resuscitation with high tidal volumes causes cerebral hemodynamic disturbance, brain inflammation and injury in preterm lambs. PLoS One 2012; 7:e39535. [PMID: 22761816 PMCID: PMC3382197 DOI: 10.1371/journal.pone.0039535] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 05/23/2012] [Indexed: 11/21/2022] Open
Abstract
AIMS Preterm infants can be inadvertently exposed to high tidal volumes (V(T)) in the delivery room, causing lung inflammation and injury, but little is known about their effects on the brain. The aim of this study was to compare an initial 15 min of high V(T) resuscitation strategy to a less injurious resuscitation strategy on cerebral haemodynamics, inflammation and injury. METHODS Preterm lambs at 126 d gestation were surgically instrumented prior to receiving resuscitation with either: 1) High V(T) targeting 10-12 mL/kg for the first 15 min (n = 6) or 2) a protective resuscitation strategy (Prot V(T)), consisting of prophylactic surfactant, a 20 s sustained inflation and a lower initial V(T) (7 mL/kg; n = 6). Both groups were subsequently ventilated with a V(T) 7 mL/kg. Blood gases, arterial pressures and carotid blood flows were recorded. Cerebral blood volume and oxygenation were assessed using near infrared spectroscopy. The brain was collected for biochemical and histologic assessment of inflammation, injury, vascular extravasation, hemorrhage and oxidative injury. Unventilated controls (UVC; n = 6) were used for comparison. RESULTS High V(T) lambs had worse oxygenation and required greater ventilatory support than Prot V(T) lambs. High V(T) resulted in cerebral haemodynamic instability during the initial 15 min, adverse cerebral tissue oxygenation index and cerebral vasoparalysis. While both resuscitation strategies increased lung and brain inflammation and oxidative stress, High V(T) resuscitation significantly amplified the effect (p = 0.014 and p<0.001). Vascular extravasation was evident in the brains of 60% of High V(T) lambs, but not in UVC or Prot V(T) lambs. CONCLUSION High V(T) resulted in greater cerebral haemodynamic instability, increased brain inflammation, oxidative stress and vascular extravasation than a Prot V(T) strategy. The initiation of resuscitation targeting Prot V(T) may reduce the severity of brain injury in preterm neonates.
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Affiliation(s)
- Graeme R Polglase
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia.
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24
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Haemoglobin transfusion threshold in very preterm newborns: A theoretical framework derived from prevailing oxygen physiology. Med Hypotheses 2012; 78:71-4. [DOI: 10.1016/j.mehy.2011.09.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 09/12/2011] [Accepted: 09/25/2011] [Indexed: 11/20/2022]
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25
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Polglase GR, Nitsos I, Baburamani AA, Crossley KJ, Slater MK, Gill AW, Allison BJ, Moss TJM, Pillow JJ, Hooper SB, Kluckow M. Inflammation in utero exacerbates ventilation-induced brain injury in preterm lambs. J Appl Physiol (1985) 2011; 112:481-9. [PMID: 22052871 DOI: 10.1152/japplphysiol.00995.2011] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cerebral blood flow disturbance is a major contributor to brain injury in the preterm infant. The initiation of ventilation may be a critical time for cerebral hemodynamic disturbance leading to brain injury in preterm infants, particularly if they are exposed to inflammation in utero. We aimed to determine whether exposure to inflammation in utero alters cardiopulmonary hemodynamics, resulting in cerebral hemodynamic disturbance and related brain injury during the initiation of ventilation. Furthermore, we aimed to determine whether inflammation in utero alters the cerebral hemodynamic response to challenge induced by high mean airway pressures. Pregnant ewes received intra-amniotic lipopolysaccharide (LPS) or saline either 2 or 4-days before preterm delivery (at 128 ± 1 days of gestation). Lambs were surgically instrumented for assessment of pulmonary and cerebral hemodynamics before delivery and positive pressure ventilation. After 30 min, lambs were challenged hemodynamically by incrementing and decrementing positive end-expiratory pressure. Blood gases, arterial pressures, and blood flows were recorded. The brain was collected for biochemical and histological assessment of inflammation, brain damage, vascular extravasation, hemorrhage, and oxidative injury. Carotid arterial pressure was higher and carotid blood flow was more variable in 2-day LPS lambs than in controls during the initial 15 min of ventilation. All lambs responded similarly to the hemodynamic challenge. Both 2- and 4-day LPS lambs had increased brain interleukin (IL)-1β, IL-6, and IL-8 mRNA expression; increased number of inflammatory cells in the white matter; increased incidence and severity of brain damage; and vascular extravasation relative to controls. Microvascular hemorrhage was increased in 2-day LPS lambs compared with controls. Cerebral oxidative injury was not different between groups. Antenatal inflammation causes adverse cerebral hemodynamics and increases the incidence and severity of brain injury in ventilated preterm lambs.
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Affiliation(s)
- Graeme R Polglase
- Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia.
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26
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Andersen CC, Pillow JJ, Gill AW, Allison BJ, Moss TJM, Hooper SB, Nitsos I, Kluckow M, Polglase GR. The cerebral critical oxygen threshold of ventilated preterm lambs and the influence of antenatal inflammation. J Appl Physiol (1985) 2011; 111:775-81. [PMID: 21719723 DOI: 10.1152/japplphysiol.00214.2011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Perinatal inflammation is associated with adverse neurodevelopmental outcomes, which may be partly due to changes in the cerebral oxygen delivery/consumption relationship. We aimed to determine the critical oxygen delivery threshold of the brain of preterm, ventilated lambs and to determine whether the critical threshold is affected by exposure to inflammation in utero. Pregnant ewes received intra-amniotic injection of lipopolysaccharide or saline at 125 or 127 days of gestation. Pulmonary and systemic flow probes and catheters were surgically positioned in the fetus immediately before delivery at 129 days of gestation. After delivery, lambs were ventilated for 90 min using a positive end-expiratory pressure recruitment strategy. Cardio-respiratory variables and blood gases were measured regularly. Systemic and cerebral oxygen delivery, consumption (Fick), and extraction were calculated, and the relationship between cerebral delivery and consumption analyzed. Linear regression was used to define the transition or "critical" oxygen threshold as the point at which the slope of the oxygen delivery/consumption curve changed to be > 10°. Four subgroups were defined according to the calculated critical threshold. A total of 150 measurements were recorded in 18 lambs. Fetal cerebral oxygen consumption was increased by antenatal lipopolysaccharide (P < 0.05). The postnatal critical oxygen threshold was 3.6 ml·kg⁻¹·min⁻¹, corresponding to cerebral oxygen consumption of 0.73 ml·kg⁻¹·min⁻¹. High oxygen delivery and consumption were associated with increased pulmonary and carotid blood flow and systemic extraction compared with low oxygen delivery and consumption. No postnatal effect of antenatal inflammation was observed. Inflammation in utero increases fetal, but not postnatal, cerebral oxygen consumption. Adverse alterations to pulmonary blood flow can result in reduced cerebral blood flow, oxygen delivery, and consumption. Regardless of exposure to inflammation, there is a consistent postnatal relationship between cerebral oxygen delivery and consumption.
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Affiliation(s)
- C C Andersen
- Perinatal Medicine, Women's and Children's Hospital, 72 King William Rd., North Adelaide, South Australia, Australia.
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27
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Abstract
Premature infants who experience cerebrovascular injury frequently have acute and long-term neurologic complications. In this article, we explore the relationship between systemic hemodynamic insults and brain injury in this patient population and the mechanisms that might be at play.
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Affiliation(s)
- Adré J. du Plessis
- Department of Neurology, Children's Hospital Boston, Boston, Massachusetts
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28
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du Plessis AJ. Cerebrovascular injury in premature infants: current understanding and challenges for future prevention. Clin Perinatol 2008; 35:609-41, v. [PMID: 19026331 DOI: 10.1016/j.clp.2008.07.010] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cerebrovascular insults are a leading cause of brain injury in premature infants, contributing to the high prevalence of motor, cognitive, and behavioral deficits. Understanding the complex pathways linking circulatory immaturity to brain injury in premature infants remains incomplete. These mechanisms are significantly different from those causing injury in the mature brain. The gaps in knowledge of normal and disturbed cerebral vasoregulation need to be addressed. This article reviews current understanding of cerebral perfusion, in the sick premature infant in particular, and discusses challenges that lie ahead.
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Affiliation(s)
- Adré J du Plessis
- Department of Neurology, Children's Hospital Boston, Boston, MA 02115, USA.
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29
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Yata K, Matchett GA, Tsubokawa T, Tang J, Kanamaru K, Zhang JH. Granulocyte-colony stimulating factor inhibits apoptotic neuron loss after neonatal hypoxia-ischemia in rats. Brain Res 2007; 1145:227-38. [PMID: 17359943 PMCID: PMC1888563 DOI: 10.1016/j.brainres.2007.01.144] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2007] [Revised: 01/27/2007] [Accepted: 01/30/2007] [Indexed: 11/30/2022]
Abstract
Neonatal hypoxia-ischemia (HI) is an important clinical problem with few effective treatments. Granulocyte-colony stimulating factor (G-CSF) is an endogenous peptide hormone of the hematopoietic system that has been shown to be neuroprotective in focal ischemia in vivo and is currently in phase I/II clinical trials for ischemic stroke in humans. We tested G-CSF in a rat model of neonatal hypoxia-ischemia in postnatal day 7 unsexed rat pups. Three groups of animals were used: hypoxia-ischemia (HI, n=67), hypoxia-ischemia with G-CSF treatment (HI+G, n=65), and healthy control (C, n=53). G-CSF (50 microg/kg, subcutaneous) was administered 1 h after HI and given on four subsequent days (five total injections). Animals were euthanized 24 h, 1, 2, and 3 weeks after HI. Assessment included brain weight, histology, immunohistochemistry, and Western blotting. G-CSF treatment was associated with improved quantitative brain weight and qualitative Nissl histology after hypoxia-ischemia. TUNEL demonstrated reduced apoptosis in group HI+G. Western blot demonstrated decreased expression of Bax and cleaved caspase-3 in group HI+G. G-CSF treatment was also associated with increased expression of STAT3, Bcl-2, and Pim-1, all of which may have participated in the anti-apoptotic effect of the drug. We conclude that G-CSF ameliorates hypoxic-ischemic brain injury and that this may occur in part by an inhibition of apoptotic cell death.
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Affiliation(s)
- Kenichiro Yata
- Department of Physiology, Loma Linda University, Loma Linda, CA 92354, USA
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30
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Tamhne S, Tuthill D, Evans A. Should ultrasound be routinely used to confirm correct positioning of nasogastric tubes in neonates? Arch Dis Child Fetal Neonatal Ed 2006; 91:F388. [PMID: 16923942 PMCID: PMC2672852 DOI: 10.1136/adc.2005.088476] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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31
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Abstract
BACKGROUND National reporting of adverse incidents has resulted in a number of clinical alerts being issued. Despite a lack of evidence, these alerts are often accompanied by a mandatory requirement to alter practice. There is likely to be clinician resistance to such a method of change management, particularly where evidence of safety is missing. AIM To determine the level of implementation within neonatal units of an alert requiring the change from litmus to pH paper to test nasogastric tube position. METHOD A questionnaire sent to all neonatal units in the United Kingdom with more than 12 cots. RESULTS From the 207 questionnaires sent, there were 165 (80%) responses. Fifty five percent of units were still using litmus. All continued to use supplementary tests not recommended in best practice statements issued at the time of the alert. There was considerable variation in the pH value at which it was considered safe to feed. CONCLUSIONS Nine months after the alert, more than half the units had not changed to pH paper, and supplementary methods of testing were still being used. The wide range of pH values highlights the uncertainty about the "normal" gastric pH in the newborn. The evidence that, in neonatal units, changing to pH paper is safer than the long established use of litmus is lacking. Recommendations for change in practice must be based on good information and not seen just as a "knee jerk" response to adverse incidents.
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Affiliation(s)
- Y Freer
- Royal Infirmary of Edinburgh, Little France, Edinburgh EH16 4SA, Scotland, UK
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32
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Bari F, Nagy K, Guidetti P, Schwarcz R, Busija DW, Domoki F. Kynurenic acid attenuates NMDA-induced pial arteriolar dilation in newborn pigs. Brain Res 2006; 1069:39-46. [PMID: 16388784 DOI: 10.1016/j.brainres.2005.11.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2005] [Revised: 11/11/2005] [Accepted: 11/14/2005] [Indexed: 11/22/2022]
Abstract
The excitatory amino acid glutamate is a potent vasodilator in the central nervous system. Glutamate-induced vasodilation is mediated primarily by N-methyl-D-aspartate (NMDA) and AMPA/kainate (KAIN) receptors. We have now tested whether two metabolites of the kynurenine pathway of tryptophan degradation acting at the NMDA receptor, the antagonist kynurenic acid (KYNA) and the agonist quinolinic acid (QUIN), are capable of modulating the dilation of pial arterioles. The closed cranial window technique was used, and changes in vessel diameter ( approximately 100 microm) were analyzed in anesthetized newborn piglets. Topical application of NMDA (10(-4) M) or KAIN (5 x 10(-5) M) resulted in marked vasodilation (44 +/- 5% and 39 +/- 4%, respectively). Neither KYNA nor QUIN (both at 10(-5) to 10(-3) M) affected the vessel diameter when applied alone. Co-application of KYNA dose-dependently reduced the vasodilation caused by 10(-4) M NMDA and also attenuated the KAIN-induced response. Ten minutes of global cerebral ischemia did not modify the interaction between KAIN and KYNA. In contrast, KYNA did not affect vasodilation to hypercapnia, elicited by the inhalation of 10% CO2. Moreover, endogenous levels of KYNA and QUIN in the cerebral cortex, hippocampus and thalamus were found to be essentially unchanged during the early reperfusion period (0.5-2 h) following an episode of cerebral ischemia. Our data are relevant for the use of drugs that target the kynurenine pathway for therapeutic interventions in cerebrovascular diseases.
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Affiliation(s)
- Ferenc Bari
- Department of Physiology, Faculty of Medicine, University of Szeged, Dóm tér 10, H-6720 Szeged, Hungary.
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33
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Freer Y, Lyon A. Nasogastric tube aspirate pH values associated with typical enteral feeding patterns in infants admitted to an NICU. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.jnn.2005.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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34
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Sun Y, Zhou C, Polk P, Nanda A, Zhang JH. Mechanisms of erythropoietin-induced brain protection in neonatal hypoxia-ischemia rat model. J Cereb Blood Flow Metab 2004; 24:259-70. [PMID: 14747752 DOI: 10.1097/01.wcb.0000110049.43905.ac] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Erythropoietin, a hemotopoietic growth factor, has brain protective actions. This study investigated the mechanisms of Recombinant Human EPO (rhEPO)-induced brain protection in neonates. An established rat hypoxia-ischemia model was used by ligation of the right common carotid artery of 7-day-old pups, followed by 90 minute of hypoxia (8% 02 and 92% N2) at 37 degrees C. Animals were divided into three groups: control, hypoxia-ischemia, and hypoxia-ischemia plus rhEPO treatment. In rhEPO treated pups, 300 units rhEPO was administered intraperitoneally 24 hours before hypoxia. rhEPO treatment (300 units) was administered daily for an additional 2 days. ELISA and immunohistochemistry examined the expression of EPO and EPOR. Brain weight, morphology, TUNEL assay, and DNA laddering evaluated brain protection. rhEPO abolished mortality (from 19% to 0%) during hypoxia insult, increased brain weight from 52% to 88%, reduced DNA fragmentation, and decreased TUNEL-positive cells. Real-time RT-PCR, Western blot, and immunohistochemistry revealed an enhanced expression of heat shock protein 27 (HSP27) in ischemic brain hemisphere. Double labeling of TUNEL with HSP27 showed most HSP27 positive cells were negative to TUNEL staining. rhEPO reduces brain injury, especially apoptotic cell death after neonatal hypoxia-ischemia, partially mediated by the activation of HSP27.
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Affiliation(s)
- Yun Sun
- Department of Neurosurgery, Louisiana State University Health Sciences Center in Shreveport, 71130, USA
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35
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Abstract
The essential role of the primary visual cortex in visual processing has been extensively studied over the last century or more. Injuries to the visual cortex in adult humans can produce blindness, referred to as "cortical blindness". In children some degree of visual recovery has been noted in comparable injuries and for that reason the term "cortical visual impairment" has been suggested as a more appropriate diagnosis in children. This term is, however, inaccurate as a significant number of children with visual loss and neurologic damage have injuries to the noncerebral pathways (for example--optic radiations in children with periventricular leukomalacia). In this study we compare visual outcomes and recovery in children with primary visual cortex lesions vs those with periventricular leukomalacia. We suggest that the poorer outcomes of children with periventricular leukomalacia could have been predicted based on studies of the mechanisms of visual recovery in infant animals following visual cortex ablation.
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Affiliation(s)
- C S Hoyt
- University of California San Francisco, 10 Koret Way, Box 0730, K301 San Francisco, CA, USA.
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36
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Nauli SM, Ally A, Zhang L, Gerthoffer WT, Pearce WJ. Maturation attenuates the effects of cGMP on contraction, [Ca2+]i and Ca2+ sensitivity in ovine basilar arteries. GENERAL PHARMACOLOGY 2000; 35:107-18. [PMID: 11707317 DOI: 10.1016/s0306-3623(01)00100-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The present study explores the hypothesis that age-related variations in cerebrovascular responses to vasodilators reflect corresponding age-dependent differences in the mechanisms coupling changes in cytosolic cGMP to vasorelaxation. The experiments focused on cGMP's ability to decrease either [Ca2+]i or myofilament Ca2+ sensitivity, because both effects can contribute to cGMP-induced vasodilation. Use of the cGMP analog 8-pCPT-cGMP minimized problems associated with limited cell permeation or cGMP hydrolysis. In fetal basilars contracted with 10 microM serotonin, the EC30 for 8-pCPT-cGMP-induced relaxation was 6 microM. In fura-2 loaded fetal basilars, pretreatment with 6 microM 8-pCPT-cGMP significantly depressed the sensitivity of [Ca2+]i to 5HT, and also myofilament sensitivity to calcium, but only in fetal arteries. In fetal basilar arteries contracted with 120 mM potassium, the EC30 for 8-pCPT-cGMP-induced relaxation was 25 microM. In fura-2 loaded ovine arteries, pretreatment with 25 microM 8-pCPT-cGMP had no effect on the ability of graded concentrations of potassium to elevate [Ca2+]i but reduced potassium's ability to induce contraction and attenuated myofilament calcium sensitivity; these latter effects were significant only in fetal arteries. In alpha-toxin permeabilized preparations, 25 microM 8-pCPT-cGMP significantly depressed both basal- and agonist-stimulated myofilament calcium sensitivity, only in fetal but not in adult basilars. Together, these results demonstrate that: (1) sensitivity to cGMP is greater in fetal than adult sheep arteries independent of method of contraction; (2) cGMP can reduce [Ca2+]i but only in agonist-contracted and not in potassium-contracted arteries; (3) and cGMP attenuates myofilament calcium sensitivity regardless of method of contraction. Overall, the data demonstrate that variations in the ability of cGMP to produce vasodilatation reflect age-, artery-, and agonist-dependent differences in the combination of mechanisms mediating responses to cGMP.
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Affiliation(s)
- S M Nauli
- Center for Perinatal Biology, Department of Physiology, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
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37
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Abstract
Septicemia is a growing problem among low birth weight infants. Early identification and treatment of sepsis in these infants would help to reduce the high mortality and morbidity seen with this disorder. Newer techniques may make earlier diagnosis a reality. In the following review article, early-onset sepsis in the premature infant is described, specifically focusing on the neonatal inflammatory response, neutropenia, and its somewhat inconsistent and delayed role as a marker for sepsis risk factors. Physiological signs, laboratory indicators, skin temperature, peripheral perfusion, and the interaction of macro-environmental factors are also discussed. Newer (neoteric) immunologic and cytokine markers of sepsis are reviewed. Finally, thermography, a noninvasive bioinstrument measuring vasoactive peripheral perfusion, which has potential for early recognition of neonatal septicemia, is described.
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MESH Headings
- Age of Onset
- Biomarkers/blood
- Cytokines/blood
- Humans
- Immunologic Tests/methods
- Infant, Newborn
- Infant, Premature, Diseases/blood
- Infant, Premature, Diseases/diagnosis
- Infant, Premature, Diseases/immunology
- Infant, Premature, Diseases/nursing
- Infant, Very Low Birth Weight
- Neonatal Nursing
- Neonatal Screening/methods
- Nurse Practitioners
- Nursing Assessment/methods
- Sepsis/blood
- Sepsis/diagnosis
- Sepsis/immunology
- Sepsis/nursing
- Thermography
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Affiliation(s)
- K M Horns
- College of Nursing, NBICU, University of Utah, Salt Lake City, USA
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38
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Marret S, Zupan V, Gressens P, Lagercrantz H, Evrard P. [Periventricular leukomalacia. I. Histological and pathophysiological aspects]. Arch Pediatr 1998; 5:525-37. [PMID: 9759188 DOI: 10.1016/s0929-693x(99)80319-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The term 'periventricular leukomalacia' (PVL) usually covers necrotic and/or gliotic lesions from perinatal origin occurring in the periventricular ring of telencephalic white matter. PVLs are found post-mortem in one third of brains from autopsies of premature infants; PVLs are diagnosed in 4 to 10% of infants born before 33 weeks of gestation and remaining alive more than 3 days after birth. PVL is very rare in at term infants. The proportion of PVLs from prenatal origin is estimated between one third and one half of cases. Recent progresses in neuroepidemiology, developmental neurobiology and imaging methods permit to revisit the pathophysiology of PVLs on a multifactorial basis. The final result of these multiple factors seem to be calcium influx due to glutamatergic overactivation triggered by cytokines, infection and inflammation, and deficit in neurotrophic factors. Periventricular topography can be explained by properties of intracerebral vascular wall at this stage of angiogenesis and by perfusion failure/hypoxia.
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Affiliation(s)
- S Marret
- Service de médecine néonatale, CHU, Rouen, France
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39
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Longo LD, Pearce WJ. High altitude, hypoxic-induced modulation of noradrenergic-mediated responses in fetal and adult cerebral arteries. Comp Biochem Physiol A Mol Integr Physiol 1998; 119:683-94. [PMID: 9683407 DOI: 10.1016/s1095-6433(98)01006-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In response to high altitude long-term hypoxemia, the cerebral arteries of adult and fetal sheep show decreased contractile responses to norepinephrine and other agonists. In this review, we examine some of the presynaptic and postsynaptic contractile mechanisms that might account for these changes. In addition, we examine cerebral vessel relaxation and the role of pregnancy in altering these responses. In general, high altitude hypoxia is associated with augmented or "upregulation" of presynaptic functions. In contrast, postsynaptic functions tend to be significantly depressed or "downregulated." The results emphasize the role of high altitude, long-term hypoxemia in modulating adrenergic-mediated signal transduction in the cerebral vasculature. They specifically highlight the profound differences in acclimatization responses between common carotid and intracranial arteries, as well as the significant differences between responses in the fetus and adult.
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Affiliation(s)
- L D Longo
- Department of Physiology, Loma Linda University, School of Medicine, California 92350, USA.
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40
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Graziani LJ, Baumgart S, Desai S, Stanley C, Gringlas M, Spitzer AR. Clinical antecedents of neurologic and audiologic abnormalities in survivors of neonatal extracorporeal membrane oxygenation. J Child Neurol 1997; 12:415-22. [PMID: 9373797 DOI: 10.1177/088307389701200702] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Extracorporeal membrane oxygenation is an effective rescue treatment for severe cardiorespiratory failure in term or near term neonates, although cerebral palsy, mental retardation, and sensorineural hearing loss are observed in 10 to 20% of survivors. The objective of the present study was to identify potential risk factors that may explain the neurologic and audiologic sequelae noted in 19% of 181 survivors of neonatal extracorporeal membrane oxygenation from our hospital. Our results suggest the following findings in survivors of severe cardiorespiratory failure treated with neonatal extracorporeal membrane oxygenation: (1) hypotension or the need for cardiopulmonary resuscitation before extracorporeal membrane oxygenation significantly increases the risk of spastic cerebral palsy, (2) profound hypocarbia before extracorporeal membrane oxygenation is associated with a significantly increased risk of hearing loss, (3) mental retardation in the absence of spastic cerebral palsy is unexplained except when due to abnormal fetal brain development, and (4) hypoxemia in the absence of hypotension does not increase the risk of neurologic or audiologic sequelae.
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Affiliation(s)
- L J Graziani
- Department of Pediatrics, Thomas Jefferson University, Jefferson Medical College, Philadelphia, PA, USA
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41
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Pane MA, Traystman RJ, Gleason CA. Ecgonine methyl ester, a major cocaine metabolite, causes cerebral vasodilation in neonatal sheep. Pediatr Res 1997; 41:815-21. [PMID: 9167194 DOI: 10.1203/00006450-199706000-00005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Maternal cocaine abuse has been associated with fetal and neonatal neurologic abnormalities, including hemorrhagic cerebral infarctions, but the mechanisms for cocaine's cerebral effects are unknown. We previously showed that acute cocaine injection causes cerebral vasodilation in cats and immature sheep; others have shown that cocaine causes cerebral vasoconstriction in piglets and in pressurized neonatal sheep arteries. Although methodologic and species differences may explain these conflicting results, we tested another possibility; that is, that ecgonine methyl ester (EME), a major cocaine metabolite in sheep, causes cerebral vasodilation and may account, in part, for cocaine's vascular effects. We studied the cerebral effects of a single i.v. injection of EME (2.5 mg/kg) in eight chronically catheterized, unanesthetized neonatal sheep (4 +/- 2 d old). We measured cerebral hemisphere blood flow (CBF) using radiolabeled microspheres, mean arterial pressure, heart rate, and arteriovenous oxygen content, and we calculated cerebral oxygen consumption (CMRo2) and cerebrovascular resistance at baseline and 0.5, 2, 5, and 60 min after EME injection. EME injection had no systemic effects, including no changes in mean arterial pressure, heart rate, or arterial blood gases. Within 0.5 min of injection, EME caused a 21% decrease in cerebrovascular resistance, which remained decreased for 60 min. CBF increased by 20% at 0.5, 2, and 5 min. Blood flow to brain regions other than the cerebral hemispheres paralleled changes in CBF, with cerebellar flow remaining increased at 60 min. There was no change in CMRo2. There was a small, but physiologically insignificant, decrease in arterial oxygen content. We conclude that EME causes cerebral vasodilation in neonatal sheep and may account, in part, for cocaine's cerebral vascular effects.
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Affiliation(s)
- M A Pane
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287-3200, USA
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Longo LD, Packianathan S. Hypoxia-ischaemia and the developing brain: hypotheses regarding the pathophysiology of fetal-neonatal brain damage. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1997; 104:652-62. [PMID: 9197867 DOI: 10.1111/j.1471-0528.1997.tb11974.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- L D Longo
- Department of Physiology, Loma Linda University, School of Medicine, California, USA
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Greenberg MK, Barsan WG, Starkman S. Neuroimaging in the emergency patient presenting with seizure. Neurology 1996; 47:26-32. [PMID: 8710090 DOI: 10.1212/wnl.47.1.26] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- M K Greenberg
- Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
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45
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Abstract
Intraventricular hemorrhage (IVH) is a common neonatal morbidity among premature infants which is diagnosed by cranial ultrasound in the newborn special care unit. Although very premature infants are more likely to experience the highest grades of hemorrhage, a number of perinatal and postnatal events have been shown to be associated with its occurrence. Factors such as vaginal delivery, labor, and intrapartum asphyxia have been associated with early onset of hemorrhage, whereas antenatal exposure to steroids may be protective. Respiratory Distress Syndrome has also been associated with hemorrhage. Since infants with a history of IVH have increased mortality rates and are at increased risk of seizures, periventricular leukomalacia, hydrocephalus, and neurodevelopmental handicap, many investigators have studied management techniques and pharmacologic interventions to decrease the incidence of IVH, including muscle paralysis, phenobarbital, Vitamin E, indomethacin, ethamsylate and surfactant. Our investigations have shown that low dose indomethacin (0.1 mg/kg i.v.) at 6-12 postnatal hours and every 24 h for two more doses decreases the incidence of all grades of IVH within the first 5 days of life. Although tremendous progress has been made in the understanding of the pathogenesis and prevention of IVH, innovative animal and human studies are needed to further reduce the incidence of this important neonatal morbidity.
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Affiliation(s)
- B Vohr
- Department of Pediatrics, Women and Infants Hospital of Rhode Island, USA
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46
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Abstract
Previous studies suggest that elevated basal levels of cGMP in newborn arteries may help explain why vascular resistance is lower in newborns than adults. To explore the reasons why basal cGMP is higher in neonatal arteries, the present studies examined rates of cGMP synthesis and degradation in newborn and adult ovine common carotid arteries. The measurements were performed in both intact and homogenized arteries, and results were normalized relative to cell water to estimate intracellular concentrations and minimize errors due to compositional differences between newborn and adult arteries. Steady state levels of cGMP measured under baseline conditions averaged 0.11 +/- 0.02 microM in adult arteries and 0.59 +/- 0.11 microM in newborn arteries. These resting cGMP levels were unaffected by endothelium removal. Under baseline conditions, steady state rates of cGMP synthesis (mumol of cGMP/L of cell water/min) were higher in newborn (0.31 +/- 0.06) than in adult (0.15 +/- 0.04) arteries. Maximal rates of cGMP degradation (mumol of cGMP/L of cell water/min) measured in artery homogenates were also much higher in preparations of newborn (106 +/- 6) than of adult (78 +/- 6) arteries. Together, these data suggest that the reason resting cGMP concentrations were higher in newborn than in adult arteries was due at least in part to a higher basal rate of cGMP synthesis in the newborn. Estimates of apparent Km values for PDE were also greater in newborn (2.9 microM) than in adult (1.5 microM) preparations, suggesting that age-related differences in the Km for PDE may also contribute to the elevated basal concentration of cGMP observed in the newborn.
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Affiliation(s)
- C R White
- Department of Physiology, Loma Linda University, California 92350, USA
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47
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Haddad J, Constantinesco A, Brunot B, Messer J. A study of cerebral perfusion using single photon emission computed tomography in neonates with brain lesions. Acta Paediatr 1994; 83:265-9. [PMID: 8038527 DOI: 10.1111/j.1651-2227.1994.tb18091.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In this study we used a single photon emission computed tomography technique (SPECT) with radiolabelled 99mTcHMPAO to assess cerebral perfusion in newborn infants with documented cerebral lesions and to determine to what extent brain SPECT might be useful in the neonatal period. A total of 15 newborn infants with the following cerebral pathologies were enrolled: severe parietal bilateral periventricular leucomalacia (PVL, n = 6); moderate parietal bilateral PVL (n = 2); intraventricular haemorrhage grade II with unilateral parietal parenchymal extension (IHV + PE, n = 3); cerebral infarction (CI, n = 2) in the zone of middle cerebral artery; and post-haemorrhagic hydrocephalus (n = 2). Follow-up was available in all infants. Alterations in cerebral perfusion were seen in only 12 of 15 infants and at the location of severe PVL, PE and CI. We have noted that the regions of diminished perfusion extended beyond the apparent extent of cerebral pathology delineated by ultrasound or magnetic resonance imaging. Markedly diminished perfusion was seen in 1 infant with hydrocephalus, which recovered following placement of ventriculo-peritoneal shunt. Regarding outcome, SPECT data failed to provide additional information than that of neuroradiological investigations. We conclude that the use of SPECT, under these conditions, to assess alteration of cerebral perfusion in the neonatal period will not provide any additional information than that of neuroradiological investigations.
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Affiliation(s)
- J Haddad
- Service de Néonatologie, Hôpital Universitaire de Strasbourg, France
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MESH Headings
- Brain/diagnostic imaging
- Cerebral Hemorrhage/diagnosis
- Cerebral Hemorrhage/diagnostic imaging
- Cerebral Hemorrhage/epidemiology
- Child
- Child, Preschool
- Female
- Humans
- Infant, Newborn
- Infant, Premature, Diseases/diagnosis
- Infant, Premature, Diseases/diagnostic imaging
- Infant, Premature, Diseases/epidemiology
- Leukomalacia, Periventricular/diagnosis
- Leukomalacia, Periventricular/diagnostic imaging
- Leukomalacia, Periventricular/epidemiology
- Magnetic Resonance Imaging
- Male
- Tomography, X-Ray Computed
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Affiliation(s)
- R N Ichord
- Department of Pediatric Neurology, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205
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50
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Abstract
Encephalopathy in the newborn has been classified in a manner suggesting that the etiology is known, such as hypoxic-ischemic and post-asphyxial encephalopathy. In the absence of evidence that most cases of newborn encephalopathy reflect these phenomena, we prefer the simple, descriptive terms, neonatal or newborn encephalopathy. Qualitative and quantitative grading schemes are described in this review and some of their potentially correctable limitations are discussed. The ideal grading scheme continues to be an unattained goal.
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Affiliation(s)
- A Leviton
- Department of Neurology, Children's Hospital, Boston, Massachusetts 02115-5747
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