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Functional, Metabolic and Morphologic Results of Ex Vivo Donor Lung Perfusion with a Perfluorocarbon-Based Oxygen Carrier Nanoemulsion in a Large Animal Transplantation Model. Cells 2020; 9:cells9112501. [PMID: 33218154 PMCID: PMC7698917 DOI: 10.3390/cells9112501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/06/2020] [Accepted: 11/09/2020] [Indexed: 01/01/2023] Open
Abstract
Background: Ex vivo lung perfusion (EVLP) is a technology that allows the re-evaluation of questionable donor lung before implantation and it has the potential to repair injured donor lungs that are otherwise unsuitable for transplantation. We hypothesized that perfluorocarbon-based oxygen carrier, a novel reconditioning strategy instilled during EVLP would improve graft function. Methods: We utilized perfluorocarbon-based oxygen carrier (PFCOC) during EVLP to recondition and improve lung graft function in a pig model of EVLP and lung transplantation. Lungs were retrieved and stored for 24 h at 4 °C. EVLP was done for 6 h with or without PFCOC. In the transplantation groups, left lung transplantation was done after EVLP with or without PFCOC. Allograft function was assessed by means of pulmonary gas exchange, lung mechanics and vascular pressures, histology and transmission electron microscopy (TEM). Results: In the EVLP only groups, physiological and biochemical markers during the 6-h perfusion period were comparable. However, perfusate lactate potassium levels were lower and ATP levels were higher in the PFCOC group. Radiologic assessment revealed significantly more lung infiltrates in the controls than in the PFCOC group (p = 0.04). In transplantation groups, perfusate glucose consumption was higher in the control group. Lactate levels were significantly lower in the PFCOC group (p = 0.02). Perfusate flavin mononucleotide (FMN) was significantly higher in the controls (p = 0.008). Post-transplant gas exchange was significantly better during the 4-h reperfusion period in the PFCOC group (p = 0.01). Plasma IL-8 and IL-12 levels were significantly lower in the PFCOC group (p = 0.01, p = 0.03, respectively). ATP lung tissue levels at the end of the transplantation were higher and myeloperoxidase (MPO) levels in lung tissue were lower in the PFCOC group compared to the control group. In the PFCOC group, TEM showed better tissue preservation and cellular viability. Conclusion: PFCOC application is safe during EVLP in lungs preserved 24 h at 4 °C. Although this strategy did not significantly affect the EVLP physiology, metabolic markers of the donor quality such as lactate production, glucose consumption, neutrophil infiltration and preservation of mitochondrial function were better in the PFCOC group. Following transplantation, PFCOC resulted in better graft function and TEM showed better tissue preservation, cellular viability and improved gas transport.
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Dodecafluoropentane Emulsion (DDFPE) as a Resuscitation Fluid for Treatment of Hemorrhagic Shock and Traumatic Brain Injury: A Review. Shock 2020; 52:50-54. [PMID: 29176401 DOI: 10.1097/shk.0000000000001060] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Dodecafluoropentane emulsion (DDFPe) is a novel nanotechnology for oxygen delivery with therapeutic potential for hemorrhagic shock and/or traumatic brain injury (TBI). DDFPe demonstrates efficacy at smaller doses than previously tested perfluorocarbon oxygen therapeutics. This smaller dose potentially eliminates toxicities exhibited by previous oxygen therapeutics, whereas anti-inflammatory properties of DDFPe may alleviate damage from ischemia reperfusion injury. This minireview summarizes our progress in developing a battlefield-ready product to prevent combat death due to hemorrhagic shock and/or TBI. Preclinical studies, for both indications, show promising effects of DDFPe as a resuscitation fluid. DDFPe may become a part of the toolkit for tactical healthcare professionals in battlefield and domestic emergency medicine.
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Deuchar GA, van Kralingen JC, Work LM, Santosh C, Muir KW, McCabe C, Macrae IM. Preclinical Validation of the Therapeutic Potential of Glasgow Oxygen Level Dependent (GOLD) Technology: a Theranostic for Acute Stroke. Transl Stroke Res 2018; 10:583-595. [PMID: 30506268 PMCID: PMC6733820 DOI: 10.1007/s12975-018-0679-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 11/13/2018] [Accepted: 11/14/2018] [Indexed: 12/20/2022]
Abstract
In acute stroke patients, penumbral tissue is non-functioning but potentially salvageable within a time window of variable duration and represents target tissue for rescue. Reperfusion by thrombolysis and/or thrombectomy can rescue penumbra and improve stroke outcomes, but these treatments are currently available to a minority of patients. In addition to the utility of Glasgow Oxygen Level Dependent (GOLD) as an MRI contrast capable of detecting penumbra, its constituent perfluorocarbon (PFC) oxygen carrier, combined with normobaric hyperoxia, also represents a potential acute stroke treatment through improved oxygen delivery to penumbra. Preclinical studies were designed to test the efficacy of an intravenous oxygen carrier, the perfluorocarbon emulsion Oxycyte® (O-PFC), combined with normobaric hyperoxia (50% O2) in both in vitro (neuronal cell culture) and in vivo rat models of ischaemic stroke. Outcome was assessed through the quantification of lipid peroxidation and oxidative stress levels, mortality, infarct volume, neurological scoring and sensorimotor tests of functional outcome in two in vivo models of stroke. Additionally, we investigated evidence for any positive or negative interactions with the thrombolytic recombinant tissue plasminogen activator (rt-PA) following embolus-induced stroke in rats. Treatment with intravenous O-PFC + normobaric hyperoxia (50% O2) provided evidence of reduced infarct size and improved functional recovery. It did not exacerbate oxidative stress and showed no adverse interactions with rt-PA. The positive results and lack of adverse effects support human trials of O-PFC + 50% O2 normobaric hyperoxia as a potential therapeutic approach. Combined with the diagnostic data presented in the preceding paper, O-PFC and normobaric hyperoxia is a potential theranostic for acute ischaemic stroke.
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Affiliation(s)
- Graeme A Deuchar
- Aurum Biosciences Ltd, 20-23 Woodside Place, Glasgow, Scotland, G3 7QL, UK.
- Institute of Neuroscience & Psychology, College of Medicine, Veterinary, and Life Sciences, University of Glasgow, Glasgow, Scotland, UK.
| | - Josie C van Kralingen
- Institute of Cardiovascular and Medical Sciences, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Lorraine M Work
- Institute of Cardiovascular and Medical Sciences, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Celestine Santosh
- Aurum Biosciences Ltd, 20-23 Woodside Place, Glasgow, Scotland, G3 7QL, UK
- Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow, Scotland, G51 4TF, UK
| | - Keith W Muir
- Institute of Neuroscience & Psychology, College of Medicine, Veterinary, and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
- Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow, Scotland, G51 4TF, UK
| | - Chris McCabe
- Institute of Neuroscience & Psychology, College of Medicine, Veterinary, and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - I Mhairi Macrae
- Institute of Neuroscience & Psychology, College of Medicine, Veterinary, and Life Sciences, University of Glasgow, Glasgow, Scotland, UK
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Abutarboush R, Mullah SH, Saha BK, Haque A, Walker PB, Aligbe C, Pappas G, Tran Ho LTV, Arnaud FG, Auker CR, McCarron RM, Scultetus AH, Moon-Massat P. Brain oxygenation with a non-vasoactive perfluorocarbon emulsion in a rat model of traumatic brain injury. Microcirculation 2018; 25:e12441. [DOI: 10.1111/micc.12441] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 01/12/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Rania Abutarboush
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
| | - Saad H. Mullah
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
| | - Biswajit K. Saha
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
| | - Ashraful Haque
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
| | - Peter B. Walker
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
| | - Chioma Aligbe
- Department of Surgery; Uniformed Services University of the Health Sciences; Bethesda MD USA
| | - Georgina Pappas
- Department of Surgery; Uniformed Services University of the Health Sciences; Bethesda MD USA
| | | | - Francoise G. Arnaud
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
- Department of Surgery; Uniformed Services University of the Health Sciences; Bethesda MD USA
| | - Charles R. Auker
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
| | - Richard M. McCarron
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
- Department of Surgery; Uniformed Services University of the Health Sciences; Bethesda MD USA
| | - Anke H. Scultetus
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
- Department of Surgery; Uniformed Services University of the Health Sciences; Bethesda MD USA
| | - Paula Moon-Massat
- NeuroTrauma Department; Naval Medical Research Center; Silver Spring MD USA
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Pericytes impair capillary blood flow and motor function after chronic spinal cord injury. Nat Med 2017; 23:733-741. [PMID: 28459438 PMCID: PMC5716958 DOI: 10.1038/nm.4331] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 03/28/2017] [Indexed: 12/19/2022]
Abstract
Blood vessels in the central nervous system (CNS) are controlled by neuronal activity. For example, widespread vessel constriction (vessel tone) is induced by brainstem neurons that release the monoamines serotonin and noradrenaline, and local vessel dilation is induced by glutamatergic neuron activity. Here we examined how vessel tone adapts to the loss of neuron-derived monoamines after spinal cord injury (SCI) in rats. We find that, months after the imposition of SCI, the spinal cord below the site of injury is in a chronic state of hypoxia owing to paradoxical excess activity of monoamine receptors (5-HT1) on pericytes, despite the absence of monoamines. This monoamine-receptor activity causes pericytes to locally constrict capillaries, which reduces blood flow to ischemic levels. Receptor activation in the absence of monoamines results from the production of trace amines (such as tryptamine) by pericytes that ectopically express the enzyme aromatic L-amino acid decarboxylase (AADC), which synthesizes trace amines directly from dietary amino acids (such as tryptophan). Inhibition of monoamine receptors or of AADC, or even an increase in inhaled oxygen, produces substantial relief from hypoxia and improves motoneuron and locomotor function after SCI.
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Mullah SH, Abutarboush R, Moon-Massat PF, Saha BK, Haque A, Walker PB, Auker CR, Arnaud FG, McCarron RM, Scultetus AH. Sanguinate's effect on pial arterioles in healthy rats and cerebral oxygen tension after controlled cortical impact. Microvasc Res 2016; 107:83-90. [PMID: 27287870 DOI: 10.1016/j.mvr.2016.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 05/23/2016] [Accepted: 06/06/2016] [Indexed: 01/18/2023]
Abstract
Sanguinate, a polyethylene glycol-conjugated carboxyhemoglobin, was investigated for cerebral vasoactivity in healthy male Sprague-Dawley rats (Study 1) and for its ability to increase brain tissue oxygen pressure (PbtO2) after controlled cortical impact (CCI) - traumatic brain injury (TBI) (Study 2). In both studies ketamine-acepromazine anesthetized rats were ventilated with 40% O2. In Study 1, a cranial window was used to measure the diameters of medium - (50-100μm) and small-sized (<50μm) pial arterioles before and after four serial infusions of Sanguinate (8mL/kg/h, cumulative 16mL/kg IV), volume-matched Hextend, or normal saline. In Study 2, PbtO2 was measured using a phosphorescence quenching method before TBI, 15min after TBI (T15) and then every 10min thereafter for 155min. At T15, rats received either 8mL/kg IV Sanguinate (40mL/kg/h) or no treatment (saline, 4mL/kg/h). Results showed: 1) in healthy rats, percentage changes in pial arteriole diameter were the same among the groups, 2) in TBI rats, PbtO2 decreased from 36.5±3.9mmHg to 19.8±3.0mmHg at T15 in both groups after TBI and did not recover in either group for the rest of the study, and 3) MAP increased 16±4mmHg and 36±5mmHg after Sanguinate in healthy and TBI rats, respectively, while MAP was unchanged in control groups. In conclusion, Sanguinate did not cause vasoconstriction in the cerebral pial arterioles of healthy rats but it also did not acutely increase PbtO2 when administered after TBI. Sanguinate was associated with an increase in MAP in both studies.
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Affiliation(s)
- Saad H Mullah
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Rania Abutarboush
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Paula F Moon-Massat
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Biswajit K Saha
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Ashraful Haque
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Peter B Walker
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Charles R Auker
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Francoise G Arnaud
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA; Uniformed Services University of the Health Sciences, Department of Surgery, Bethesda, MD 20814, USA.
| | - Richard M McCarron
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA; Uniformed Services University of the Health Sciences, Department of Surgery, Bethesda, MD 20814, USA.
| | - Anke H Scultetus
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA; Uniformed Services University of the Health Sciences, Department of Surgery, Bethesda, MD 20814, USA.
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Perfluorocarbon NVX-108 increased cerebral oxygen tension after traumatic brain injury in rats. Brain Res 2016; 1634:132-139. [PMID: 26794250 DOI: 10.1016/j.brainres.2016.01.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 12/23/2015] [Accepted: 01/08/2016] [Indexed: 11/23/2022]
Abstract
BACKGROUND Hypoxia is a critical secondary injury mechanism in traumatic brain injury (TBI), and early intervention to alleviate post-TBI hypoxia may be beneficial. NVX-108, a dodecafluoropentane perfluorocarbon, was screened for its ability to increase brain tissue oxygen tension (PbtO2) when administered soon after TBI. METHODS Ketamine-acepromazine anesthetized rats ventilated with 40% oxygen underwent moderate controlled cortical impact (CCI)-TBI at time 0 (T0). Rats received either no treatment (NON, n=8) or 0.5 ml/kg intravenous (IV) NVX-108 (NVX, n=9) at T15 (15 min after TBI) and T75. RESULTS Baseline cortical PbtO2 was 28±3 mm Hg and CCI-TBI resulted in a 46±6% reduction in PbtO2 at T15 (P<0.001). Significant differences in time-group interactions (P=0.013) were found when comparing either absolute or percentage change of PbtO2 to post-injury (mixed-model ANOVA) suggesting that administration of NVX-108 increased PbtO2 above injury levels while it remained depressed in the NON group. Specifically in the NVX group, PbtO2 increased to a peak 143% of T15 (P=0.02) 60 min after completion of NVX-108 injection (T135). Systemic blood pressure was not different between the groups. CONCLUSION NVX-108 caused an increase in PbtO2 following CCI-TBI in rats and should be evaluated further as a possible immediate treatment for TBI.
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Cox A, Varma A, Banik N. Recent advances in the pharmacologic treatment of spinal cord injury. Metab Brain Dis 2015; 30:473-82. [PMID: 24833553 PMCID: PMC4233197 DOI: 10.1007/s11011-014-9547-y] [Citation(s) in RCA: 36] [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: 02/03/2014] [Accepted: 04/10/2014] [Indexed: 12/16/2022]
Abstract
A need exists for the effective treatment of individuals suffering from spinal cord injury (SCI). Recent advances in the understanding of the pathophysiological mechanisms occurring in SCI have resulted in an expansion of new therapeutic targets. This review summarizes both preclinical and clinical findings investigating the mechanisms and cognate pharmacologic therapeutics targeted to modulate hypoxia, ischemia, excitotoxicity, inflammation, apoptosis, epigenetic alterations, myelin regeneration and scar remodeling. Successful modulation of these targets has been demonstrated in both preclinical and clinical studies with agents such as Oxycyte, Minocycline, Riluzole, Premarin, Cethrin, and ATI-355. The translation of these agents into clinical studies highlights the progress the field has made in the past decade. SCI proves to be a complex condition; the numerous pathophysiological mechanisms occurring at varying time points suggests that a single agent approach to the treatment of SCI may not be optimal. As the field continues to mature, the hope is that the knowledge gained from these studies will be applied to the development of an effective multi-pronged treatment strategy for SCI.
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Affiliation(s)
- April Cox
- Department of Neurosciences, Medical University of South Carolina, 96 Jonathan Lucas ST. MSC606, Charleston, SC, 29425, USA,
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Yacoub A, Hajec MC, Stanger R, Wan W, Young H, Mathern BE. Neuroprotective effects of perflurocarbon (oxycyte) after contusive spinal cord injury. J Neurotrauma 2013; 31:256-67. [PMID: 24025081 DOI: 10.1089/neu.2013.3037] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Spinal cord injury (SCI) often results in irreversible and permanent neurological deficits and long-term disability. Vasospasm, hemorrhage, and loss of microvessels create an ischemic environment at the site of contusive or compressive SCI and initiate the secondary injury cascades leading to progressive tissue damage and severely decreased functional outcome. Although the initial mechanical destructive events cannot be reversed, secondary injury damage occurs over several hours to weeks, a time frame during which therapeutic intervention could be achieved. One essential component of secondary injury cascade is the reduction in spinal cord blood flow with resultant decrease in oxygen delivery. Our group has recently shown that administration of fluorocarbon (Oxycyte) significantly increased parenchymal tissue oxygen levels during the usual postinjury hypoxic phase, and fluorocarbon has been shown to be effective in stroke and head injury. In the current study, we assessed the beneficial effects of Oxycyte after a moderate-to-severe contusion SCI was simulated in adult Long-Evans hooded rats. Histopathology and immunohistochemical analysis showed that the administration of 5 mL/kg of Oxycyte perfluorocarbon (60% emulsion) after SCI dramatically reduced destruction of spinal cord anatomy and resulted in a marked decrease of lesion area, less cell death, and greater white matter sparing at 7 and 42 days postinjury. Terminal deoxynucleotidyl transferase dUTP nick end labeling staining showed a significant reduced number of apoptotic cells in Oxycyte-treated animals, compared to the saline group. Collectively, these results demonstrate the potential neuroprotective effect of Oxycyte treatment after SCI, and its beneficial effects may be, in part, a result of reducing apoptotic cell death and tissue sparing. Further studies to determine the most efficacious Oxycyte dose and its mechanisms of protection are warranted.
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Affiliation(s)
- Adly Yacoub
- 1 Department of Neurosurgery, Virginia Commonwealth University , Richmond, Virginia
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Li H, Wijekoon A, Leipzig ND. Encapsulated Neural Stem Cell Neuronal Differentiation in Fluorinated Methacrylamide Chitosan Hydrogels. Ann Biomed Eng 2013; 42:1456-69. [DOI: 10.1007/s10439-013-0925-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 10/07/2013] [Indexed: 12/15/2022]
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Mahon RT, Hall A, Bodo M, Auker C. The intravenous perfluorocarbon emulsion Oxycyte does not increase hyperbaric oxygen-related seizures in a non-sedated swine model. Eur J Appl Physiol 2013; 113:2795-802. [PMID: 24062008 DOI: 10.1007/s00421-013-2720-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 08/27/2013] [Indexed: 11/30/2022]
Abstract
PURPOSE Standard treatment for decompression sickness (DCS) is recompression therapy with hyperbaric oxygen (HBO). Non-recompressive therapies are needed to address mass casualty scenarios such as a disabled submarine rescue or DCS therapy in remote environments. Intravenously delivered perfluorocarbon (PFC) emulsions improve blood oxygen content and decrease mortality in several animal models of DCS. However, the enhanced oxygen delivery of PFC emulsions may increase CNS oxygen toxicity (seizures) risk when used in conjunction with HBO. We studied seizure latency and duration in swine randomized to receive PFC or normal saline with 6 ATA of oxygen. METHODS Yorkshire swine (n = 31) were fitted with EEG electrodes and randomized to receive 5 ml/kg of the PFC Oxycyte (Oxygen Biotherapeutics Inc., Morrisville, NC) or saline intravenously 1 h before HBO. Unsedated animals were fitted with a snout mask for inhaled gas delivery, positioned inside the hyperbaric chamber, and compressed to 165 ft of sea water (6 ATA). After 2.5 min at 6 ATA, breathing gas was switched to 100 % O2 until signs of seizure were observed and EEG activity was evident. At seizure onset gas was switched back to air for 3 min, then the chamber was decompressed. After 24 h, the dive profile/oxygen exposure was repeated to ensure no secondary effects of PFC drug redistribution or emulsion metabolism. RESULTS/CONCLUSION Intravenous PFC emulsion did not decrease seizure latency or increase duration on initial HBO exposure or after 24 h. This finding demonstrates the safety of PFC use in conjunction with recompression therapy to treat DCS.
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Affiliation(s)
- Richard T Mahon
- Undersea Medicine Department, Naval Medical Research Center, 503 Robert Grant Ave., Silver Spring, MD, 20910-7500, USA,
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Spiess BD. Perfluorocarbon emulsions as a promising technology: a review of tissue and vascular gas dynamics. J Appl Physiol (1985) 2009; 106:1444-52. [PMID: 19179651 DOI: 10.1152/japplphysiol.90995.2008] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Perfluorocarbon (PFC) emulsions are halogen-substituted carbon nonpolar oils with resultant enhanced dissolved respiratory gas (O(2), N(2), CO(2), nitric oxide) capabilities. In the first demonstration of enhanced O(2) solubility, inhaled PFC could sustain rat metabolism. Intravenous emulsions were then trialed as "blood substitutes." In the last 10 yr, biocomputational modeling has enhanced our mechanistic understanding of PFCs. Contemporary research is now taking advantage of these physiological discoveries and applying PFCs as "oxygen therapeutics," as well as ways to enhance other gas movements. One particularly promising area of research is the treatment of gas embolism (arterial and venous emboli/decompression sickness). An expansive understanding of PFC-enhanced diffusive gas movements through tissue and vasculature may have analogous applications for O(2) or other respiratory gases and should provide a revolution in medicine. This review will stress the fundamental knowledge we now have regarding how respiratory gas movements are changed when intravenous PFC is present.
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Affiliation(s)
- Bruce D Spiess
- Department of Anesthesiology and Emergency Medicine, Virginia Commonwealth University Reanimation Engineering Shock Center, Richmond, Virginia, USA.
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