1
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Morin C, Simard É, See W, Sage M, Imane R, Nadeau C, Samson N, Lavoie PM, Chabot B, Marouan S, Tremblay S, Praud JP, Micheau P, Fortin-Pellerin É. Total liquid ventilation in an ovine model of extreme prematurity: a randomized study. Pediatr Res 2024; 95:974-980. [PMID: 37833531 DOI: 10.1038/s41390-023-02841-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/16/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023]
Abstract
BACKGROUND This study aimed at comparing cardiorespiratory stability during total liquid ventilation (TLV)-prior to lung aeration-with conventional mechanical ventilation (CMV) in extremely preterm lambs during the first 6 h of life. METHODS 23 lambs (11 females) were born by c-section at 118-120 days of gestational age (term = 147 days) to receive 6 h of TLV or CMV from birth. Lung samples were collected for RNA and histology analyses. RESULTS The lambs under TLV had higher and more stable arterial oxygen saturation (p = 0.001) and cerebral tissue oxygenation (p = 0.02) than the lambs in the CMV group in the first 10 min of transition to extrauterine life. Although histological assessment of the lungs was similar between the groups, a significant upregulation of IL-1a, IL-6 and IL-8 RNA in the lungs was observed after TLV. CONCLUSIONS Total liquid ventilation allowed for remarkably stable transition to extrauterine life in an extremely preterm lamb model. Refinement of our TLV prototype and ventilation algorithms is underway to address specific challenges in this population, such as minimizing tracheal deformation during the active expiration. IMPACT Total liquid ventilation allows for remarkably stable transition to extrauterine life in an extremely preterm lamb model. Total liquid ventilation is systematically achievable over the first 6 h of life in the extremely premature lamb model. This study provides additional incentive to pursue further investigation of total liquid ventilation as a transition tool for the most extreme preterm neonates.
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Affiliation(s)
- Christophe Morin
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Émile Simard
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Wendy See
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Michaël Sage
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Roqaya Imane
- Department of Pediatrics, Université de Montréal, Montreal, QC, Canada
| | - Charlène Nadeau
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Nathalie Samson
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Pascal M Lavoie
- Division of Neonatology, Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada
| | - Benoît Chabot
- Department of Microbiology and Infectiology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Sofia Marouan
- Department of Pathology, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Sophie Tremblay
- Department of Pediatrics, Université de Montréal, Montreal, QC, Canada
| | - Jean-Paul Praud
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada
- Department of Pediatrics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Philippe Micheau
- Department of Mechanical Engineering, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Étienne Fortin-Pellerin
- Department of Pharmacology-Physiology, Université de Sherbrooke, Sherbrooke, QC, Canada.
- Department of Pediatrics, Université de Sherbrooke, Sherbrooke, QC, Canada.
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2
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Fallon BP, Lautner-Csorba O, Major TC, Lautner G, Harvey SL, Langley MW, Johnson MD, Saveski C, Matusko N, Rabah R, Rojas-Pena A, Meyerhoff ME, Bartlett RH, Mychaliska GB. Extracorporeal life support without systemic anticoagulation: a nitric oxide-based non-thrombogenic circuit for the artificial placenta in an ovine model. Pediatr Res 2024; 95:93-101. [PMID: 37087539 PMCID: PMC10600655 DOI: 10.1038/s41390-023-02605-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 01/26/2023] [Accepted: 03/20/2023] [Indexed: 04/24/2023]
Abstract
BACKGROUND Clinical translation of the extracorporeal artificial placenta (AP) is impeded by the high risk for intracranial hemorrhage in extremely premature newborns. The Nitric Oxide Surface Anticoagulation (NOSA) system is a novel non-thrombogenic extracorporeal circuit. This study aims to test the NOSA system in the AP without systemic anticoagulation. METHODS Ten extremely premature lambs were delivered and connected to the AP. For the NOSA group, the circuit was coated with DBHD-N2O2/argatroban, 100 ppm nitric oxide was blended into the sweep gas, and no systemic anticoagulation was given. For the Heparin control group, a non-coated circuit was used and systemic anticoagulation was administered. RESULTS Animals survived 6.8 ± 0.6 days with normal hemodynamics and gas exchange. Neither group had any hemorrhagic or thrombotic complications. ACT (194 ± 53 vs. 261 ± 86 s; p < 0.001) and aPTT (39 ± 7 vs. 69 ± 23 s; p < 0.001) were significantly lower in the NOSA group than the Heparin group. Platelet and leukocyte activation did not differ significantly from baseline in the NOSA group. Methemoglobin was 3.2 ± 1.1% in the NOSA group compared to 1.6 ± 0.6% in the Heparin group (p < 0.001). CONCLUSIONS The AP with the NOSA system successfully supported extremely premature lambs for 7 days without significant bleeding or thrombosis. IMPACT The Nitric Oxide Surface Anticoagulation (NOSA) system provides effective circuit-based anticoagulation in a fetal sheep model of the extracorporeal artificial placenta (AP) for 7 days. The NOSA system is the first non-thrombogenic circuit to consistently obviate the need for systemic anticoagulation in an extracorporeal circuit for up to 7 days. The NOSA system may allow the AP to be implemented clinically without systemic anticoagulation, thus greatly reducing the intracranial hemorrhage risk for extremely low gestational age newborns. The NOSA system could potentially be applied to any form of extracorporeal life support to reduce or avoid systemic anticoagulation.
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Affiliation(s)
- Brian P Fallon
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Orsolya Lautner-Csorba
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Terry C Major
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Gergely Lautner
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Stephen L Harvey
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Mark W Langley
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Matthew D Johnson
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Claudia Saveski
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Niki Matusko
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Raja Rabah
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Alvaro Rojas-Pena
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Surgery, Section of Transplantation, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Mark E Meyerhoff
- Department of Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Robert H Bartlett
- Department of Surgery, ECLS Laboratory, University of Michigan Medical School, Ann Arbor, MI, USA
| | - George B Mychaliska
- Department of Surgery, Section of Pediatric Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
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3
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Kukora SK, Mychaliska GB, Weiss EM. Ethical challenges in first-in-human trials of the artificial placenta and artificial womb: not all technologies are created equally, ethically. J Perinatol 2023; 43:1337-1342. [PMID: 37400494 DOI: 10.1038/s41372-023-01713-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 06/07/2023] [Accepted: 06/21/2023] [Indexed: 07/05/2023]
Abstract
Artificial placenta and artificial womb technologies to support extremely premature neonates are advancing toward clinical testing in humans. Currently, no recommendations exist comparing these approaches to guide study design and optimal enrollment eligibility adhering to principles of research ethics. In this paper, we will explore how scientific differences between the artificial placenta and artificial womb approaches create unique ethical challenges to designing first-in-human trials of safety and provide recommendations to guide ethical study design for initial human translation.
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Affiliation(s)
- Stephanie K Kukora
- Division of Neonatology, Department of Pediatrics, Children's Mercy Hospital, Kansas City, MO, USA.
- Children's Mercy Bioethics Center, Children's Mercy Hospital, Kansas City, MO, USA.
| | - George B Mychaliska
- Department of Surgery, Section of Pediatric Surgery, Fetal Diagnosis and Treatment Center, University of Michigan, Michigan Medicine, Ann Arbor, MI, USA
| | - Elliott Mark Weiss
- Division of Neonatology, Department of Pediatrics, University of Washington School of Medicine, Seattle, WA, USA
- Treuman Katz Center for Pediatric Bioethics, Seattle Children's Research Institute, Seattle, WA, USA
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4
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Flake AW, De Bie FR, Munson DA, Feudtner C. The artificial placenta and EXTEND technologies: one of these things is not like the other. J Perinatol 2023; 43:1343-1348. [PMID: 37393398 DOI: 10.1038/s41372-023-01716-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/15/2023] [Accepted: 06/23/2023] [Indexed: 07/03/2023]
Abstract
The so called "Artificial Placenta" and "Artificial Womb" (EXTEND) technologies share a common goal of improving outcomes for extreme premature infants. Beyond that goal, they are very dissimilar and, in our view, differ sufficiently in their technology, intervention strategy, demonstrated physiology, and risk profiles that bundling them together for consideration of the ethical challenges in designing first in human trials is misguided. In this response to the commentary by Kukora and colleagues, we will provide our perspective on these differences, and how they impact ethical clinical study design for first-in-human trials of safety/feasibility, and subsequently efficacy of the two technologies.
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Affiliation(s)
- Alan W Flake
- Department of Surgery, Center for Fetal Research, Children's Hospital of Philadelphia, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Felix R De Bie
- Department of Surgery, Center for Fetal Research, Children's Hospital of Philadelphia, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David A Munson
- Division of Neonatology, Children's Hospital of Philadelphia, Department of Pediatrics, Perelman School of Medicine, Universityof Pennsylvania, Philadelphia, PA, USA
| | - Chris Feudtner
- Department of Medical Ethics, Children's Hospital of Philadelphia, and Departments of Pediatrics and of Medical Ethics and Health Policy, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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5
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Dahm SI, Kenna KR, Stewart D, Pereira-Fantini PM, McCall KE, Perkins EJ, Sourial M, Tingay DG. Aeration strategy at birth does not impact carotid haemodynamics in preterm lambs. Pediatr Res 2023; 93:1226-1232. [PMID: 35974157 PMCID: PMC10132978 DOI: 10.1038/s41390-022-02244-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/21/2022] [Accepted: 07/26/2022] [Indexed: 11/09/2022]
Abstract
BACKGROUND The impact of different respiratory strategies at birth on the preterm lung is well understood; however, concerns have been raised that lung recruitment may impede cerebral haemodynamics. This study aims to examine the effect of three different ventilation strategies on carotid blood flow, carotid artery oxygen content and carotid oxygen delivery. METHODS 124-127-day gestation apnoeic intubated preterm lambs studied as part of a larger programme primarily assessing lung injury were randomised to positive pressure ventilation with positive end-expiratory pressure (PEEP) 8 cmH2O (No-RM; n = 12), sustained inflation (SI; n = 15) or dynamic PEEP strategy (DynPEEP; maximum PEEP 14 or 20 cmH2O, n = 41) at birth, followed by 90 min of standardised ventilation. Haemodynamic data were continuously recorded, with intermittent arterial blood gas analysis. RESULTS Overall carotid blood flow measures were comparable between strategies. Except for mean carotid blood flow that was significantly lower for the SI group compared to the No-RM and DynPEEP groups over the first 3 min (p < 0.0001, mixed effects model). Carotid oxygen content and oxygen delivery were similar between strategies. Maximum PEEP level did not alter cerebral haemodynamic measures. CONCLUSIONS Although there were some short-term variations in cerebral haemodynamics between different PEEP strategies and SI, these were not sustained. IMPACT Different pressure strategies to facilitate lung aeration at birth in preterm infants have been proposed. There is minimal information on the effect of lung recruitment on cerebral haemodynamics. This is the first study that compares the effect of sustained lung inflation and dynamic and static positive end-expiratory pressure on cerebral haemodynamics. We found that the different ventilation strategies did not alter carotid blood flow, carotid oxygen content or carotid oxygen delivery. This preclinical study provides some reassurance that respiratory strategies designed to focus on lung aeration at birth may not impact cerebral haemodynamics in preterm neonates.
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Affiliation(s)
- Sophia I Dahm
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia.
| | - Kelly R Kenna
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia
| | - David Stewart
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Neonatology, The Royal Children's Hospital, Parkville, VIC, Australia
| | - Prue M Pereira-Fantini
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
| | - Karen E McCall
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Neonatology, The Royal Children's Hospital, Parkville, VIC, Australia
| | - Elizabeth J Perkins
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Neonatology, The Royal Children's Hospital, Parkville, VIC, Australia
| | - Magdy Sourial
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia
| | - David G Tingay
- Neonatal Research, Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Neonatology, The Royal Children's Hospital, Parkville, VIC, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
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6
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An Artificial Placenta Experimental System in Sheep: Critical Issues for Successful Transition and Survival up to One Week. Biomedicines 2023; 11:biomedicines11030702. [PMID: 36979681 PMCID: PMC10044909 DOI: 10.3390/biomedicines11030702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 03/03/2023] Open
Abstract
Objective: To describe the development of an artificial placenta (AP) system in sheep with learning curve and main bottlenecks to allow survival up to one week. Methods: A total of 28 fetal sheep were transferred to an AP system at 110–115 days of gestation. The survival goal in the AP system was increased progressively in three consecutive study groups: 1–3 h (n = 8), 4–24 h (n = 10) and 48–168 h (n = 10). Duration of cannulation procedure, technical complications, pH, lactate, extracorporeal circulation (EC) circuit flows, fetal heart rate, and outcomes across experiments were compared. Results: There was a progressive reduction in cannulation complications (75%, 50% and 0%, p = 0.004), improvement in initial pH (7.20 ± 0.06, 7.31 ± 0.04 and 7.33 ± 0.02, p = 0.161), and increment in the rate of experiments reaching survival goal (25%, 70% and 80%, p = 0.045). In the first two groups, cannulation accidents, air bubbles in the extracorporeal circuit, and thrombotic complications were the most common cause of AP system failure. Conclusions: Achieving a reproducible experimental setting for an AP system is extremely challenging, time- and effort-consuming, and requires a highly multidisciplinary team. As a result of the learning curve, we achieved reproducible transition and survival up to 7 days. Extended survival requires improving instrumentation with custom-designed devices.
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7
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Omecinski KS, Frankowski BJ, Federspiel WJ. Design and In Vitro Evaluation of an Artificial Placenta Made From Hollow Fiber Membranes. ASAIO J 2023; 69:e86-e92. [PMID: 36716073 PMCID: PMC9897463 DOI: 10.1097/mat.0000000000001862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
For infants born at the border of viability, care practices and morbimortality rates vary widely between centers. Trends show significant improvement, however, with increasing gestational age and weight. For periviable infants, the goal of critical care is to bridge patients to improved outcomes. Current practice involves ventilator therapy, resulting in chronic lung injuries. Research has turned to artificial uterine environments, where infants are submerged in an artificial amniotic fluid bath and provided respiratory assistance via an artificial placenta. We have developed the Preemie-Ox, a hollow fiber membrane bundle that provides pumpless respiratory support via umbilical cord cannulation. Computational fluid dynamics was used to design an oxygenator that could achieve a carbon dioxide removal rate of 12.2 ml/min, an outlet hemoglobin saturation of 100%, and a resistance of less than 71 mmHg/L/min at a blood flow rate of 165 ml/min. A prototype was utilized to evaluate in-vitro gas exchange, resistance, and plasma-free hemoglobin generation. In-vitro gas exchange was 4% higher than predicted results and no quantifiable plasma-free hemoglobin was produced.
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Affiliation(s)
- Katelin S Omecinski
- From the McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Brian J Frankowski
- From the McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - William J Federspiel
- From the McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
- Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
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8
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Spencer BL, Mychaliska GB. Milestones for clinical translation of the artificial placenta. Semin Fetal Neonatal Med 2022; 27:101408. [PMID: 36437184 DOI: 10.1016/j.siny.2022.101408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Despite significant advances in the treatment of prematurity, premature birth results in significant mortality and morbidity. In particular, extremely low gestational age newborns (ELGANs) defined as <28 weeks estimated gestational age (EGA) suffer from disproportionate mortality and morbidity. A radical paradigm shift in the treatment of prematurity is to recreate fetal physiology using an extracorporeal VV-ECLS artificial placenta (AP) or an AV-ECLS artificial womb (AW). Over the past 15 years, tremendous advances have been made in the laboratory confirming long-term support and organ protection and ongoing development. The major milestones to clinical application are miniaturization, anticoagulation, clinical risk stratification, specialized critical care protocols, a regulatory path and a strategy and platform to translate technology to the bedside. Currently, several groups are addressing the remaining milestones for clinical translation.
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Affiliation(s)
- Brianna L Spencer
- Department of Surgery, University of Michigan, 2101 Taubman Center 1500 E Medical Center Dr, Ann Arbor, MI, 48109, USA.
| | - George B Mychaliska
- Section of Pediatric Surgery, Department of Surgery, Fetal Diagnosis and Treatment Center, C.S. Mott Children's Hospital, 1540 E Hospital Dr, Ann Arbor, MI, 48109, USA.
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9
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Charest-Pekeski AJ, Cho SKS, Aujla T, Sun L, Floh AA, McVey MJ, Sheta A, Estrada M, Crawford-Lean L, Foreman C, Mroczek D, Belik J, Saini BS, Lim JM, Moir OJ, Lee FT, Quinn M, Darby JRT, Seed M, Morrison JL, Haller C. Impact of the Addition of a Centrifugal Pump in a Preterm Miniature Pig Model of the Artificial Placenta. Front Physiol 2022; 13:925772. [PMID: 35941934 PMCID: PMC9356302 DOI: 10.3389/fphys.2022.925772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 06/22/2022] [Indexed: 11/28/2022] Open
Abstract
The recent demonstration of normal development of preterm sheep in an artificial extrauterine environment has renewed interest in artificial placenta (AP) systems as a potential treatment strategy for extremely preterm human infants. However, the feasibility of translating this technology to the human preterm infant remains unknown. Here we report the support of 13 preterm fetal pigs delivered at 102 ± 4 days (d) gestation, weighing 616 ± 139 g with a circuit consisting of an oxygenator and a centrifugal pump, comparing these results with our previously reported pumpless circuit (n = 12; 98 ± 4 days; 743 ± 350 g). The umbilical vessels were cannulated, and fetuses were supported for 46.4 ± 46.8 h using the pumped AP versus 11 ± 13 h on the pumpless AP circuit. Upon initiation of AP support on the pumped system, we observed supraphysiologic circuit flows, tachycardia, and hypertension, while animals maintained on a pumpless AP circuit exhibited subphysiologic flows. On the pumped AP circuit, there was a progressive decline in umbilical vein (UV) flow and oxygen delivery. We conclude that the addition of a centrifugal pump to the AP circuit improves survival of preterm pigs by augmenting UV flow through the reduction of right ventricular afterload. However, we continued to observe the development of heart failure within a matter of days.
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Affiliation(s)
- Alex J. Charest-Pekeski
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Steven K. S. Cho
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, SA, Australia
| | - Tanroop Aujla
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Liqun Sun
- Division of Cardiology, The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, ON, Canada
| | - Alejandro A. Floh
- Division of Cardiology, The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Critical Care Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Mark J. McVey
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Anesthesiology and Pain Medicine, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
- Department of Physics, Ryerson University, Toronto, ON, Canada
| | - Ayman Sheta
- Department of Pediatrics, Division of Neonatology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Marvin Estrada
- Lab Animal Services, Peter Gilgan Center for Research and Learning, The Hospital for Sick Children, Toronto, ON, Canada
| | - Lynn Crawford-Lean
- Division of Cardiovascular Surgery, The Labatt Family Heart Centre, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Celeste Foreman
- Division of Cardiovascular Surgery, The Labatt Family Heart Centre, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Dariusz Mroczek
- Division of Cardiology, The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, ON, Canada
| | - Jaques Belik
- Department of Pediatrics, Division of Neonatology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Brahmdeep S. Saini
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
- Institute of Medical Science, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Jessie Mei Lim
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Olivia J. Moir
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Fu-Tsuen Lee
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Megan Quinn
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, SA, Australia
| | - Jack R. T. Darby
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, SA, Australia
| | - Mike Seed
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Division of Cardiology, The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, ON, Canada
- Institute of Medical Science, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Janna L. Morrison
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, SA, Australia
| | - Christoph Haller
- Division of Cardiovascular Surgery, The Labatt Family Heart Centre, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
- *Correspondence: Christoph Haller,
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10
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Burgos CM, Frenckner B, Broman LM. Premature and Extracorporeal Life Support: Is it Time? A Systematic Review. ASAIO J 2022; 68:633-645. [PMID: 34593681 DOI: 10.1097/mat.0000000000001555] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Early preterm birth < 34 gestational weeks (GA) and birth weight (BW) <2 kg are relative contraindications for extracorporeal membrane oxygenation (ECMO). However, with improved technology, ECMO is presently managed more safely and with decreasing complications. Thus, these relative contraindications may no longer apply. We performed a systematic review to evaluate the existing literature on ECMO in early and late (34-37 GA) prematurity focusing on survival to hospital discharge and the complication intracranial hemorrhage (ICH). Data sources: MEDLINE, PubMed, Web of Science, Embase, and the Cochrane Database. Only publications in the English language were evaluated. Of the 36 included studies, 23 were related to ECMO support for respiratory failure, 10 for cardiac causes, and four for congenital diaphragmatic hernia (CDH). Over the past decades, the frequency of ICH has declined (89-21%); survival has increased in both early prematurity (25-76%), and in CDH (33-75%), with outcome similar to late prematurity (48%). The study was limited by an inherent risk of bias from overlapping single-center and registry data. Both the risk of ICH and death have decreased in prematurely born treated with ECMO. We challenge the 34 week GA time limit for ECMO and propose an international task force to revise current guidelines. At present, gestational age < 34 weeks might no longer be considered a contraindication for ECMO in premature neonates.
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Affiliation(s)
- Carmen Mesas Burgos
- From the Department of Pediatric Surgery, Karolinska University Hospital, Stockholm, Sweden
- ECMO Centre Karolinska, Pediatric Perioperative Medicine and Intensive Care, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Björn Frenckner
- From the Department of Pediatric Surgery, Karolinska University Hospital, Stockholm, Sweden
- ECMO Centre Karolinska, Pediatric Perioperative Medicine and Intensive Care, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Lars Mikael Broman
- ECMO Centre Karolinska, Pediatric Perioperative Medicine and Intensive Care, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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11
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Fallon BP, Mychaliska GB. Development of an artificial placenta for support of premature infants: narrative review of the history, recent milestones, and future innovation. Transl Pediatr 2021; 10:1470-1485. [PMID: 34189106 PMCID: PMC8192990 DOI: 10.21037/tp-20-136] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Over 50 years ago, visionary researchers began work on an extracorporeal artificial placenta to support premature infants. Despite rudimentary technology and incomplete understanding of fetal physiology, these pioneering scientists laid the foundation for future work. The research was episodic, as medical advances improved outcomes of premature infants and extracorporeal life support (ECLS) was introduced for the treatment of term and near-term infants with respiratory or cardiac failure. Despite ongoing medical advances, extremely premature infants continue to suffer a disproportionate burden of mortality and morbidity due to organ immaturity and unintended iatrogenic consequences of medical treatment. With advancing technology and innovative approaches, there has been a resurgence of interest in developing an artificial placenta to further diminish the mortality and morbidity of prematurity. Two related but distinct platforms have emerged to support premature infants by recreating fetal physiology: a system based on arteriovenous (AV) ECLS and one based on veno-venous (VV) ECLS. The AV-ECLS approach utilizes only the umbilical vessels for cannulation. It requires immediate transition of the infant at the time of birth to a fluid-filled artificial womb to prevent umbilical vessel spasm and avoid gas ventilation. In contradistinction, the VV-ECLS approach utilizes the umbilical vein and the internal jugular vein. It would be applied after birth to infants failing maximal medical therapy or preemptively if risk stratified for high mortality and morbidity. Animal studies are promising, demonstrating prolonged support and ongoing organ development in both systems. The milestones for clinical translation are currently being evaluated.
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Affiliation(s)
- Brian P Fallon
- Department of Surgery, University of Michigan, Michigan Medicine, Ann Arbor, Michigan, USA
| | - George B Mychaliska
- Department of Surgery, Section of Pediatric Surgery, Fetal Diagnosis and Treatment Center, University of Michigan, Michigan Medicine, Ann Arbor, Michigan, USA
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12
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Darby JRT, Berry MJ, Quinn M, Holman SL, Bradshaw EL, Jesse SM, Haller C, Seed M, Morrison JL. Haemodynamics and cerebral oxygenation of neonatal piglets in the immediate ex utero period supported by mechanical ventilation or ex utero oxygenator. J Physiol 2021; 599:2751-2761. [PMID: 33745149 DOI: 10.1113/jp280803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 03/15/2021] [Indexed: 12/29/2022] Open
Abstract
KEY POINTS The margin of human viability has extended to the extremes of gestational age (<24 weeks) when the lungs are immature and ventilator-induced lung injury is common. Artificial placenta technology aims to extend gestation ex utero in order to allow the lungs additional time to develop prior to entering an air-breathing environment. We compared the haemodynamics and cerebral oxygenation of piglets in the immediate period post-oxygenator (OXY) transition against both paired in utero measures and uniquely against piglets transitioned onto mechanical ventilation (VENT). Post-transition, OXY piglets became hypotensive with reduced carotid blood flow in comparison with both paired in utero measures and VENT piglets. The addition of a pump to the oxygenator circuit may be required to ensure haemodynamic stability in the immediate post-transition period. ABSTRACT Gestational age at birth is a major predictor of wellbeing; the lower the gestational age, the greater the risk of mortality and morbidity. At the margins of human viability (<24 weeks gestation) immature lungs combined with the need for early ventilatory support means lung injury and respiratory morbidity is common. The abrupt haemodynamic changes consequent on birth may also contribute to preterm-associated brain injury, including intraventricular haemorrhage. Artificial placenta technology aims to support oxygenation, haemodynamic stability and ongoing fetal development ex utero until mature enough to safely transition to a true ex utero environment. We aimed to characterize the impact of birth transition onto either an oxygenator circuit or positive pressure ventilation on haemodynamic and cerebral oxygenation of the neonatal piglet. At 112 days gestation (term = 115 days), fetal pigs underwent instrumentation surgery and transitioned onto either an oxygenator (OXY, n = 5) or ventilatory support (VENT, n = 8). Blood pressure (BP), carotid blood flow and cerebral oxygenation in VENT piglets rose from in utero levels to be significantly higher than OXY piglets post-transition. OXY piglet BP, carotid blood flow and carotid oxygen delivery (DO2 ) decreased from in utero levels post-transition; however, cerebral regional oxygen saturation (rSO2 ) was maintained at fetal-like levels. OXY piglets became hypoxaemic and retained CO2 . Whether OXY piglets are able to maintain cerebral rSO2 under these conditions for a prolonged period is yet to be determined. Improvements to OXY piglet oxygenation may lie in maintaining piglet BP at in utero levels and enhancing oxygenator circuit flow.
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Affiliation(s)
- Jack R T Darby
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Mary J Berry
- Centre for Translational Physiology, University of Otago, Wellington, New Zealand.,Department of Paediatrics and Child Health, University of Otago, Wellington, New Zealand
| | - Megan Quinn
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Stacey L Holman
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Emma L Bradshaw
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Sarah M Jesse
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Christoph Haller
- Univeristy of Toronto and The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Mike Seed
- Univeristy of Toronto and The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Janna L Morrison
- Early Origins of Adult Health Research Group, Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
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13
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Charest‐Pekeski AJ, Sheta A, Taniguchi L, McVey MJ, Floh A, Sun L, Aujla T, Cho SKS, Ren J, Crawford‐Lean L, Foreman C, Lim JM, Saini BS, Estrada M, Lam A, Belik J, Mroczek D, Quinn M, Holman SL, Darby JRT, Seed M, Morrison JL, Haller C. Achieving sustained extrauterine life: Challenges of an artificial placenta in fetal pigs as a model of the preterm human fetus. Physiol Rep 2021; 9:e14742. [PMID: 33650787 PMCID: PMC7923578 DOI: 10.14814/phy2.14742] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 01/12/2021] [Indexed: 11/24/2022] Open
Abstract
Artificial placenta (AP) technology aims to maintain fetal circulation, while promoting the physiologic development of organs. Recent reports of experiments performed in sheep indicate the intrauterine environment can be recreated through the cannulation of umbilical vessels, replacement of the placenta with a low-resistance membrane oxygenator, and incubation of the fetus in fluid. However, it remains to be seen whether animal fetuses similar in size to the extremely preterm human infant that have been proposed as a potential target for this technology can be supported in this way. Preterm Yucatan miniature piglets are similar in size to extremely preterm human infants and share similar umbilical cord anatomy, raising the possibility to serve as a good model to investigate the AP. To characterize fetal cardiovascular physiology, the carotid artery (n = 24) was cannulated in utero and umbilical vein (UV) and umbilical artery were sampled. Fetal UV flow was measured by MRI (n = 16). Piglets were delivered at 98 ± 4 days gestation (term = 115 days), cannulated, and supported on the AP (n = 12) for 684 ± 228 min (range 195-3077 min). UV flow was subphysiologic (p = .002), while heart rate was elevated on the AP compared with in utero controls (p = .0007). We observed an inverse relationship between heart rate and UV flow (r2 = .4527; p < .001) with progressive right ventricular enlargement that was associated with reduced contractility and ultimately hydrops and circulatory collapse. We attribute this to excessive afterload imposed by supraphysiologic circuit resistance and augmented sympathetic activity. We conclude that short-term support of the preterm piglet on the AP is feasible, although we have not been able to attain normal fetal physiology. In the future, we propose to investigate the feasibility of an AP circuit that incorporates a centrifugal pump in our miniature pig model.
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Affiliation(s)
- Alex J. Charest‐Pekeski
- Department of PhysiologyUniversity of TorontoTorontoOntarioCanada
- Translational MedicineThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Ayman Sheta
- Department of PediatricsDivision of NeonatologyThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Luiza Taniguchi
- Division of CardiologyThe Labatt Family Heart CentreThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Mark J. McVey
- Department of Anesthesia and Pain MedicineDepartment of Anesthesiology and Pain MedicineThe Hospital for Sick ChildrenUniversity of TorontoTorontoOntarioCanada
- Department of PhysicsRyerson UniversityTorontoOntarioCanada
| | - Alejandro Floh
- Division of CardiologyThe Labatt Family Heart CentreThe Hospital for Sick ChildrenTorontoOntarioCanada
- Department of Critical Care MedicineThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Liqun Sun
- Division of CardiologyThe Labatt Family Heart CentreThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Tanroop Aujla
- Department of PhysiologyUniversity of TorontoTorontoOntarioCanada
- Translational MedicineThe Hospital for Sick ChildrenTorontoOntarioCanada
- Early Origins of Adult Health Research GroupHealth and Biomedical InnovationClinical and Health SciencesUniversity of South AustraliaAdelaideSouth AustraliaAustralia
| | - Steven K. S. Cho
- Department of PhysiologyUniversity of TorontoTorontoOntarioCanada
- Translational MedicineThe Hospital for Sick ChildrenTorontoOntarioCanada
- Early Origins of Adult Health Research GroupHealth and Biomedical InnovationClinical and Health SciencesUniversity of South AustraliaAdelaideSouth AustraliaAustralia
| | - Jiaqi Ren
- Department of PhysiologyUniversity of TorontoTorontoOntarioCanada
- Translational MedicineThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Lynn Crawford‐Lean
- Division of Cardiovascular SurgeryThe Labatt Family Heart CentreThe Hospital for Sick ChildrenUniversity of TorontoTorontoCanada
| | - Celeste Foreman
- Division of Cardiovascular SurgeryThe Labatt Family Heart CentreThe Hospital for Sick ChildrenUniversity of TorontoTorontoCanada
| | - Jessie Mei Lim
- Department of PhysiologyUniversity of TorontoTorontoOntarioCanada
- Translational MedicineThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Brahmdeep S. Saini
- Translational MedicineThe Hospital for Sick ChildrenTorontoOntarioCanada
- Institute of Medical ScienceUniversity of TorontoTorontoOntarioCanada
| | - Marvin Estrada
- Lab Animal ServicesResearch InstituteThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Anson Lam
- Lab Animal ServicesResearch InstituteThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Jaques Belik
- Department of PhysiologyUniversity of TorontoTorontoOntarioCanada
| | - Dariusz Mroczek
- Division of CardiologyThe Labatt Family Heart CentreThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Megan Quinn
- Early Origins of Adult Health Research GroupHealth and Biomedical InnovationClinical and Health SciencesUniversity of South AustraliaAdelaideSouth AustraliaAustralia
| | - Stacey L. Holman
- Early Origins of Adult Health Research GroupHealth and Biomedical InnovationClinical and Health SciencesUniversity of South AustraliaAdelaideSouth AustraliaAustralia
| | - Jack R. T. Darby
- Early Origins of Adult Health Research GroupHealth and Biomedical InnovationClinical and Health SciencesUniversity of South AustraliaAdelaideSouth AustraliaAustralia
| | - Mike Seed
- Department of PhysiologyUniversity of TorontoTorontoOntarioCanada
- Division of CardiologyThe Labatt Family Heart CentreThe Hospital for Sick ChildrenTorontoOntarioCanada
- Institute of Medical ScienceUniversity of TorontoTorontoOntarioCanada
| | - Janna L. Morrison
- Early Origins of Adult Health Research GroupHealth and Biomedical InnovationClinical and Health SciencesUniversity of South AustraliaAdelaideSouth AustraliaAustralia
| | - Christoph Haller
- Division of Cardiovascular SurgeryThe Labatt Family Heart CentreThe Hospital for Sick ChildrenUniversity of TorontoTorontoCanada
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14
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De Bie FR, Davey MG, Larson AC, Deprest J, Flake AW. Artificial placenta and womb technology: Past, current, and future challenges towards clinical translation. Prenat Diagn 2020; 41:145-158. [PMID: 32875581 DOI: 10.1002/pd.5821] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/24/2020] [Accepted: 08/29/2020] [Indexed: 01/12/2023]
Abstract
Extreme prematurity remains a major cause of neonatal mortality and severe long-term morbidity. Current neonatal care is associated with significant morbidity due to iatrogenic injury and developmental immaturity of extreme premature infants. A more physiologic approach, replacing placental function and providing a womb-like environment, is the foundational principle of artificial placenta (AP) and womb (AW) technology. The concept has been studied during the past 60 years with limited success. However, recent technological advancements and a greater emphasis on mimicking utero-placental physiology have improved the success of experimental models, bringing the technology closer to clinical translation. Here, we review the rationale for and history of AP and AW technology, discuss the challenges that needed to be overcome, and compare recent successful models. We conclude by outlining some remaining challenges to be addressed on the path towards clinical translation and opportunities for future research.
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Affiliation(s)
- Felix R De Bie
- Center for Fetal Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Marcus G Davey
- Center for Fetal Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Abby C Larson
- Center for Fetal Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Jan Deprest
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Alan W Flake
- Center for Fetal Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
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15
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Nitzan M, Nitzan I, Arieli Y. The Various Oximetric Techniques Used for the Evaluation of Blood Oxygenation. SENSORS 2020; 20:s20174844. [PMID: 32867184 PMCID: PMC7506757 DOI: 10.3390/s20174844] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 12/12/2022]
Abstract
Adequate oxygen delivery to a tissue depends on sufficient oxygen content in arterial blood and blood flow to the tissue. Oximetry is a technique for the assessment of blood oxygenation by measurements of light transmission through the blood, which is based on the different absorption spectra of oxygenated and deoxygenated hemoglobin. Oxygen saturation in arterial blood provides information on the adequacy of respiration and is routinely measured in clinical settings, utilizing pulse oximetry. Oxygen saturation, in venous blood (SvO2) and in the entire blood in a tissue (StO2), is related to the blood supply to the tissue, and several oximetric techniques have been developed for their assessment. SvO2 can be measured non-invasively in the fingers, making use of modified pulse oximetry, and in the retina, using the modified Beer–Lambert Law. StO2 is measured in peripheral muscle and cerebral tissue by means of various modes of near infrared spectroscopy (NIRS), utilizing the relative transparency of infrared light in muscle and cerebral tissue. The primary problem of oximetry is the discrimination between absorption by hemoglobin and scattering by tissue elements in the attenuation measurement, and the various techniques developed for isolating the absorption effect are presented in the current review, with their limitations.
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Affiliation(s)
- Meir Nitzan
- Department of Physics/Electro-Optics Engineering, Jerusalem College of Technology, 21 Havaad Haleumi St., Jerusalem 91160, Israel;
- Correspondence:
| | - Itamar Nitzan
- Monash Newborn, Monash Children’s Hospital, Melbourne 3168, Australia;
- Department of Neonatology, Shaare Zedek Medical Center, Shmuel Bait St 12, Jerusalem 9103102, Israel
| | - Yoel Arieli
- Department of Physics/Electro-Optics Engineering, Jerusalem College of Technology, 21 Havaad Haleumi St., Jerusalem 91160, Israel;
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16
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Chitty LS, Hui L, Ghidini A, Levy B, Deprest J, Van Mieghem T, Bianchi DW. In case you missed it: The Prenatal Diagnosis editors bring you the most significant advances of 2019. Prenat Diagn 2020; 40:287-293. [PMID: 31875323 DOI: 10.1002/pd.5632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 12/18/2019] [Indexed: 12/21/2022]
Affiliation(s)
- L S Chitty
- London North Genomic Laboratory, Great Ormond Street NHS Foundation Trust, and Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, London, UK
| | - L Hui
- Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - A Ghidini
- Antenatal Testing Centre, Inova Alexandria Hospital, Alexandria, VA
| | - B Levy
- Departments of Pathology and Cell Biology, Columbia University, New York, NY
| | - J Deprest
- Departments of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
| | - T Van Mieghem
- Department of Obstetrics and Gynaecology, Mount Sinai Hospital and University of Toronto, Toronto, Ontario, Canada
| | - D W Bianchi
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD
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17
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Church JT, Werner NL, Coughlin MA, Menzel-Smith J, Najjar M, Carr BD, Parmar H, Neil J, Alexopoulos D, Perez-Torres C, Ge X, Beeman SC, Garbow JR, Mychaliska GB. Effects of an artificial placenta on brain development and injury in premature lambs. J Pediatr Surg 2018; 53:1234-1239. [PMID: 29605267 PMCID: PMC5994355 DOI: 10.1016/j.jpedsurg.2018.02.091] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 02/27/2018] [Indexed: 02/07/2023]
Abstract
PURPOSE We evaluated whether brain development continues and brain injury is prevented during Artificial Placenta (AP) support utilizing extracorporeal life support (ECLS). METHODS Lambs at EGA 118days (term=145; n=4) were placed on AP support (venovenous ECLS with jugular drainage and umbilical vein reinfusion) for 7days and sacrificed. Early (EGA 118; n=4) and late (EGA 127; n=4) mechanical ventilation (MV) lambs underwent conventional MV for up to 48h and were sacrificed, and early (n=5) and late (n=5) tissue control (TC) lambs were sacrificed at delivery. Brains were harvested, formalin-fixed, rehydrated, and studied by magnetic resonance imaging (MRI). The gyrification index (GI), a measure of cerebral folding complexity, was calculated for each brain. Diffusion-weighted imaging was used to determine fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in multiple structures to assess white matter (WM) integrity. RESULTS No intracranial hemorrhage was observed. GI was similar between AP and TC groups. ADC and FA did not differ between AP and late TC groups in any structure. Compared to late MV brains, AP brains demonstrated significantly higher ADC (0.45±0.08 vs. 0.27±0.11, p=0.02) and FA (0.61±0.04 vs. 0.44±0.05; p=0.006) in the cerebral peduncles. CONCLUSIONS After 7days of AP support, WM integrity is preserved relative to mechanical ventilation. TYPE OF STUDY Research study.
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Affiliation(s)
- Joseph T. Church
- Extracorporeal Life Support Laboratory, Department of Surgery, Michigan Medicine, Ann Arbor, MI
| | - Nicole L. Werner
- Extracorporeal Life Support Laboratory, Department of Surgery, Michigan Medicine, Ann Arbor, MI
| | - Meghan A. Coughlin
- Extracorporeal Life Support Laboratory, Department of Surgery, Michigan Medicine, Ann Arbor, MI
| | - Julia Menzel-Smith
- Extracorporeal Life Support Laboratory, Department of Surgery, Michigan Medicine, Ann Arbor, MI
| | - Mary Najjar
- Extracorporeal Life Support Laboratory, Department of Surgery, Michigan Medicine, Ann Arbor, MI
| | - Benjamin D. Carr
- Extracorporeal Life Support Laboratory, Department of Surgery, Michigan Medicine, Ann Arbor, MI
| | - Hemant Parmar
- Department of Radiology, Michigan Medicine, Ann Arbor, MI
| | - Jeff Neil
- Department of Neurology, Boston Children’s Hospital, Boston, MA
| | | | - Carlos Perez-Torres
- Biomedical Magnetic Resonance Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO
| | - Xia Ge
- Biomedical Magnetic Resonance Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO
| | - Scott C. Beeman
- Biomedical Magnetic Resonance Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO
| | - Joel R. Garbow
- Biomedical Magnetic Resonance Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO
| | - George B. Mychaliska
- Extracorporeal Life Support Laboratory, Department of Surgery, Michigan Medicine, Ann Arbor, MI
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