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Seno S, Wang J, Cao S, Saraswati M, Park S, Simoni J, Ma L, Soltys B, Hsia CJC, Koehler RC, Robertson CL. Resuscitation with macromolecular superoxide dismutase/catalase mimetic polynitroxylated PEGylated hemoglobin offers neuroprotection in guinea pigs after traumatic brain injury combined with hemorrhage shock. BMC Neurosci 2020; 21:22. [PMID: 32404052 PMCID: PMC7222507 DOI: 10.1186/s12868-020-00571-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 05/09/2020] [Indexed: 12/21/2022] Open
Abstract
Background Polynitroxylated PEGylated hemoglobin (PNPH, aka SanFlow) possesses superoxide dismutase/catalase mimetic activities that may directly protect the brain from oxidative stress. Stabilization of PNPH with bound carbon monoxide prevents methemoglobin formation during storage and permits it to serve as a carbon monoxide donor. We determined whether small volume transfusion of hyperoncotic PNPH is neuroprotective in a polytrauma model of traumatic brain injury (TBI) plus hemorrhagic shock. Guinea pigs were used because, like humans, they do not synthesize their own ascorbic acid, which is important in reducing methemoglobin. Results TBI was produced by controlled cortical impact and was followed by 20 mL/kg hemorrhage to a mean arterial pressure (MAP) of 40 mmHg. At 90 min, animals were resuscitated with 20 mL/kg lactated Ringer’s solution or 10 mL/kg PNPH. Resuscitation with PNPH significantly augmented the early recovery of MAP after hemorrhagic shock by 10–18 mmHg; whole blood methemoglobin was only 1% higher and carboxyhemoglobin was 2% higher. At 9 days of recovery, unbiased stereology analysis revealed that, compared to animals resuscitated with lactated Ringer’s solution, those treated with PNPH had significantly more viable neurons in the hippocampus CA1 + 2 region (59 ± 10% versus 87 ± 18% of sham and naïve mean value) and in the dentate gyrus (70 ± 21% versus 96 ± 24%; n = 12 per group). Conclusion PNPH may serve as a small-volume resuscitation fluid for polytrauma involving TBI and hemorrhagic shock. The neuroprotection afforded by PNPH seen in other species was sustained in a species without endogenous ascorbic acid synthesis, thereby supporting potential translatability for human use.
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Affiliation(s)
- Soichiro Seno
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 600 North Wolfe Street, Blalock 1404, Baltimore, MD, USA.,Division of Traumatology, Research Institute, National Defense Medical College, Saitama, Japan
| | - Jun Wang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 600 North Wolfe Street, Blalock 1404, Baltimore, MD, USA
| | - Suyi Cao
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 600 North Wolfe Street, Blalock 1404, Baltimore, MD, USA
| | - Manda Saraswati
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 600 North Wolfe Street, Blalock 1404, Baltimore, MD, USA
| | - Sharon Park
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 600 North Wolfe Street, Blalock 1404, Baltimore, MD, USA
| | - Jan Simoni
- AntiRadical Therapeutics, Sioux Falls, SD, USA
| | - Li Ma
- Department of Physics, Georgia Southern University, Statesboro, GA, USA
| | | | | | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 600 North Wolfe Street, Blalock 1404, Baltimore, MD, USA.
| | - Courtney L Robertson
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, 600 North Wolfe Street, Blalock 1404, Baltimore, MD, USA
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Alomari E, Ronda L, Bruno S, Paredi G, Marchetti M, Bettati S, Olivari D, Fumagalli F, Novelli D, Ristagno G, Latini R, Cooper CE, Reeder BJ, Mozzarelli A. High- and low-affinity PEGylated hemoglobin-based oxygen carriers: Differential oxidative stress in a Guinea pig transfusion model. Free Radic Biol Med 2018; 124:299-310. [PMID: 29920341 PMCID: PMC6191936 DOI: 10.1016/j.freeradbiomed.2018.06.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/11/2018] [Accepted: 06/15/2018] [Indexed: 12/26/2022]
Abstract
Hemoglobin-based oxygen carriers (HBOCs) are an investigational replacement for blood transfusions and are known to cause oxidative damage to tissues. To investigate the correlation between their oxygen binding properties and these detrimental effects, we investigated two PEGylated HBOCs endowed with different oxygen binding properties - but otherwise chemically identical - in a Guinea pig transfusion model. Plasma samples were analyzed for biochemical markers of inflammation, tissue damage and organ dysfunction; proteins and lipids of heart and kidney extracts were analyzed for markers of oxidative damage. Overall, both HBOCs produced higher oxidative stress in comparison to an auto-transfusion control group. Particularly, tissue 4-hydroxynonenal adducts, tissue malondialdehyde adducts and plasma 8-oxo-2'-deoxyguanosine exhibited significantly higher levels in comparison with the control group. For malondialdehyde adducts, a higher level in the renal tissue was observed for animals treated with the high-affinity HBOC, hinting at a correlation between the HBOCs oxygen binding properties and the oxidative stress they produce. Moreover, we found that the high-affinity HBOC produced greater tissue oxygenation in comparison with the low affinity one, possibly correlating with the higher oxidative stress it induced.
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Affiliation(s)
- Esra'a Alomari
- Department of Food and Drug, University of Parma, Parma, Italy
| | - Luca Ronda
- Department of Medicine and Surgery, University of Parma, Parma, Italy; Biopharmanet-TEC, University of Parma, Parma, Italy
| | - Stefano Bruno
- Department of Food and Drug, University of Parma, Parma, Italy; Biopharmanet-TEC, University of Parma, Parma, Italy.
| | - Gianluca Paredi
- Department of Food and Drug, University of Parma, Parma, Italy; Interdepartmental Center SITEIA.PARMA, University of Parma, Parma 43121, Italy
| | - Marialaura Marchetti
- Department of Medicine and Surgery, University of Parma, Parma, Italy; Biopharmanet-TEC, University of Parma, Parma, Italy
| | - Stefano Bettati
- Department of Medicine and Surgery, University of Parma, Parma, Italy; Biopharmanet-TEC, University of Parma, Parma, Italy; Istituto Nazionale Biostrutture e Biosistemi, Rome, Italy
| | - Davide Olivari
- Istituto di Ricerche Farmacologiche 'Mario Negri', Milan, Italy
| | | | - Deborah Novelli
- Istituto di Ricerche Farmacologiche 'Mario Negri', Milan, Italy
| | | | - Roberto Latini
- Istituto di Ricerche Farmacologiche 'Mario Negri', Milan, Italy
| | - Chris E Cooper
- School of Biological Sciences, University of Essex, Colchester, United Kingdom
| | - Brandon J Reeder
- School of Biological Sciences, University of Essex, Colchester, United Kingdom
| | - Andrea Mozzarelli
- Department of Food and Drug, University of Parma, Parma, Italy; Biopharmanet-TEC, University of Parma, Parma, Italy; Istituto Nazionale Biostrutture e Biosistemi, Rome, Italy; Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Pisa, Italy
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Schoettker P, Marcucci CE, Casso G, Heim C. Revisiting transfusion safety and alternatives to transfusion. Presse Med 2016; 45:e331-40. [DOI: 10.1016/j.lpm.2016.06.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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Abstract
A hemoglobin (Hb) wrapped covalently by human serum albumins (HSAs), a core-shell structured hemoglobin-albumin cluster designated as "HemoAct", is an O2-carrier designed for use as a red blood cell (RBC) substitute. This report describes the blood compatibility, hemodynamic response, and pharmacokinetic properties of HemoAct, and then explains its preclinical safety. Viscosity and blood cell counting measurements revealed that HemoAct has good compatibility with whole blood. Intravenous administration of HemoAct into anesthetized rats elicited no unfavorable increase in systemic blood pressure by vasoconstriction. The half-life of (125)I-labeled HemoAct in circulating blood is markedly longer than that of HSA. Serum biochemical tests conducted 7 days after HemoAct infusion yielded equivalent values to those observed in the control group with HSA. Histopathologic inspections of the vital organs revealed no marked abnormality in their tissues. All results indicate that HemoAct has sufficient preclinical safety as an alternative material for RBC transfusion.
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Awasthi V, Yadav VR, Goins B, Phillips WT. Modulation of oxidative stability of haemoglobin inside liposome-encapsulated haemoglobin. J Microencapsul 2012; 30:471-8. [PMID: 23231644 DOI: 10.3109/02652048.2012.752535] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The major hurdle in the formulation of liposome-encapsulated haemoglobin (LEH) is the oxidation of haemoglobin (Hb) into methaemoglobin during storage and after administration. In order to reduce this oxidative degradation, we tested various reducing conditions in the presence of catalase. We found that at 37°C more than 50% of Hb oxidized to methaemoglobin within 24 h, whereas in presence of catalase, the oxidation was significantly reduced. The effect of catalase was further enhanced by a reduction mixture containing β-NAD, d-glucose, adenine, inosine, MgCl2, KCl, KH2PO4 and Na2HPO4; only 14% methaemoglobin was generated in the presence of catalase and reduction mixture. Contrary to the expectation, glutathione, deferoxamine and homocysteine enhanced Hb oxidation. The presence of CRM inside liposomes (250 nm) significantly decreased Hb oxidation. The results suggest that catalase and a well-defined mixture of co-factors may help control Hb oxidation for improvement in the functional life of LEH.
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Affiliation(s)
- Vibhudutta Awasthi
- College of Pharmacy, University of Oklahoma Health Sciences Center, 1110 North Stonewall Avenue, Oklahoma City, OK 73117, USA.
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Buehler PW, Baek JH, Lisk C, Connor I, Sullivan T, Kominsky D, Majka S, Stenmark KR, Nozik-Grayck E, Bonaventura J, Irwin DC. Free hemoglobin induction of pulmonary vascular disease: evidence for an inflammatory mechanism. Am J Physiol Lung Cell Mol Physiol 2012; 303:L312-26. [PMID: 22728465 DOI: 10.1152/ajplung.00074.2012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Cell-free hemoglobin (Hb) exposure may be a pathogenic mediator in the development of pulmonary arterial hypertension (PAH), and when combined with chronic hypoxia the potential for exacerbation of PAH and vascular remodeling is likely more pronounced. We hypothesized that Hb may contribute to hypoxia-driven PAH collectively as a prooxidant, inflammatory, and nitric oxide (NO) scavenger. Using programmable micropump technology, we exposed male Sprague-Dawley rats housed under room air or hypoxia to 12 or 30 mg per day Hb for 3, 5, and 7 wk. Blood pressure, cardiac output, right ventricular hypertrophy, and indexes of pulmonary vascular remodeling were evaluated. Additionally, markers of oxidative stress, NO bioavailability and inflammation were determined. Hb increased pulmonary arterial (PA) pressure, pulmonary vessel wall stiffening, and right heart hypertrophy with temporal and dose dependence in both room air and hypoxic cohorts. Hb induced a modest increase in plasma oxidative stress markers (malondialdehyde and 4-hydroxynonenal), no change in NO bioavailability, and increased lung ICAM protein expression. Treatment with the antioxidant Tempol attenuated Hb-induced pulmonary arterial wall thickening, but not PA pressures or ICAM expression. Chronic exposure to low plasma Hb concentrations (range = 3-10 μM) lasting up to 7 wk in rodents induces pulmonary vascular disease via inflammation and to a lesser extent by Hb-mediated oxidation. Tempol demonstrated a modest effect on the attenuation of Hb-induced pulmonary vascular disease. NO bioavailability was found to be of minimal importance in this model.
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Affiliation(s)
- Paul W Buehler
- Laboratory of Biochemistry and Vascular Biology, Office of Blood Research and Review, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, Bethesda, MD, USA
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Driessen B, Jahr JS, Lurie F, Gunther RA. Effects of isovolemic resuscitation with hemoglobin-based oxygen carrier Hemoglobin glutamer-200 (bovine) on systemic and mesenteric perfusion and oxygenation in a canine model of hemorrhagic shock: a comparison with 6% hetastarch solution and shed blood. Vet Anaesth Analg 2006; 33:368-80. [PMID: 17083609 DOI: 10.1111/j.1467-2995.2005.00280.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To study Hemoglobin glutamer-200 bovine (Hb-200), 6% hetastarch (HES) and shed whole blood (WB) resuscitation in canine hemorrhagic shock. STUDY DESIGN Prospective laboratory investigation. Animals Twelve adult dogs [29 +/- 1 kg (mean +/- SD)]. METHODS Anesthetized dogs were instrumented for recording systemic and mesenteric hemodynamic parameters and withdrawal of arterial, mixed and mesenteric venous blood, in which hematological, oxygenation, blood gas and acid-bases variables were determined. Recordings were made before [baseline (BL)], after 1 hour of hypovolemia and immediately and 3 hours post-resuscitation with 30 mL kg(-1) of either Hb-200, HES, or WB. RESULTS Blood withdrawal (average 34 +/- 2 mL kg(-1)) caused significant hemodynamic changes, metabolic acidosis and hyperlactatemia characteristic for hemorrhagic shock. Only WB transfusion restored all variables. Hemoglobin glutamer-200 bovine infusion returned most hemodynamic parameters including cardiac output and mesenteric arterial blood flow to BL but increased mean arterial pressure above BL (p < 0.05). However, Hb-200 failed to restore total Hb and arterial oxygen content (CaO2), leaving systemic (DO2I) and mesenteric O2 delivery (DO2Im) below BL (p < 0.05). Nevertheless, acid-base variables recovered completely after Hb-200 resuscitation, and met-hemoglobin (Met-Hb) levels increased (p < 0.05). Hetastarch resuscitation returned hemodynamic variables to or above BL but further decreased total Hb and CaO2, preventing recovery of sDO2I and mDO2I (p < 0.05). Thus, systemic and mesenteric O2 extraction stayed above BL (p < 0.05) while acid-base variables recovered to BL, although slower than in Hb-200 and WB groups (p < 0.05). CONCLUSIONS AND CLINICAL RELEVANCE Resuscitation with Hb-200 seemed to resolve metabolic acidosis and lactatemia more rapidly than HES, but not WB; yet it is not superior to HES in improving DO2I and DO2Im. The hyperoncotic property of solutions like Hb-200 that results in rapid volume expansion with more homogenous microvascular perfusion and the ability to facilitate diffusive O2 transfer accelerating metabolic recovery may be the key mechanisms underlying their beneficial effects as resuscitants.
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Affiliation(s)
- B Driessen
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, PA 19348, USA.
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Drobin D, Kjellstrom BT, Malm E, Malavalli A, Lohman J, Vandegriff KD, Young MA, Winslow RM. Hemodynamic response and oxygen transport in pigs resuscitated with maleimide-polyethylene glycol-modified hemoglobin (MP4). J Appl Physiol (1985) 2004; 96:1843-53. [PMID: 14729723 DOI: 10.1152/japplphysiol.00530.2003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cell-free Hb increases systemic and pulmonary pressure and resistance and reduces cardiac output and heart rate in animals and humans, effects that have limited their clinical development as “blood substitutes.” The primary aim of this study was to evaluate the hemodynamic response to infusion of several formulations of a new polyethylene glycol (PEG)-modified human Hb [maleimide PEG Hb (MalPEGHb)] in swine, an animal known to be sensitive to Hb-induced vasoconstriction. Anesthetized animals underwent controlled hemorrhage (50% of blood volume), followed by resuscitation (70% of shed volume) with 10% pentastarch (PS), 4% MalPEG-Hb in lactated Ringer (MP4), 4% MalPEG-Hb in pentastarch (HS4), 2% MalPEG-Hb in pentastarch (HS2), or 4% stroma-free Hb in lactated Ringer solution (SFH). Compared with baseline, restoration of blood volume after resuscitation was similar and not significantly different for the PS (103%), HS2 (99%), HS4 (106%), and MP4 (87%) animals but significantly less for the SFH animals (66%) ( P < 0.05). All solutions that contained MalPEG-Hb restored mean arterial and pulmonary pressure and cardiac output. Systemic vascular resistance was unchanged, and pulmonary arterial pressure and resistance were increased slightly. Both systemic and pulmonary vascular resistance increased significantly in animals that received SFH, despite less adequate blood volume restoration. Oxygen consumption was maintained in all animals that received MalPEG-Hb, but not PS. Base excess improved only with MalPEG-Hb and PS, but not SFH. Red blood cell O2extraction was significantly increased in animals that received Hb, regardless of formulation. These data demonstrate resuscitation with MalPEG-human Hb without increasing systemic vascular resistance and support our previous observations in animals suggesting that the efficacy of low concentrations of PEG-Hb in the plasma results from reduced vasoconstriction.
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Affiliation(s)
- Dan Drobin
- Department of Anesthesiology, Karolinska Institute at Söder Hospital, S-118 83 Stockholm, Sweden
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Wettstein R, Tsai AG, Erni D, Winslow RM, Intaglietta M. Resuscitation with polyethylene glycol-modified human hemoglobin improves microcirculatory blood flow and tissue oxygenation after hemorrhagic shock in awake hamsters. Crit Care Med 2003; 31:1824-30. [PMID: 12794426 DOI: 10.1097/01.ccm.0000069340.16319.f2] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To determine whether resuscitation with polyethylene glycol-modified human hemoglobin (MalPEG-Hb), an oxygen-carrying blood replacement fluid with 4 g/dL Hb, viscosity of 2.5 cP, colloid osmotic pressure of 49 mm Hg, and p50 of 5.5 mm Hg, improves systemic and microvascular variables after hemorrhage compared with shed blood (SB) and 5% hydroxyethyl starch (HES). SETTING Laboratory. SUBJECTS Golden Syrian hamsters. DESIGN Prospective study. INTERVENTIONS Hamsters implemented with a skin fold chamber were hemorrhaged 50% of blood volume and resuscitated with 50% shed blood volume (SB, HES, or MalPEG-Hb). MEASUREMENTS AND MAIN RESULTS Shock and resuscitation were monitored for 1 hr each. Microvascular events were characterized in terms of vessel diameter, flow velocity, functional capillary density, and Po(2) in arterioles, venules, and extravascular tissue. Systemic variables include mean arterial pressure, heart rate, Po(2), Pco(2), pH, and base excess. MalPEG-Hb resuscitation increased functional capillary density to 64% vs. 44% for SB and 32% for HES relative to baseline before shock. Microvascular flow increased 16% for MalPEG-Hb relative to baseline and remained decreased by 44% for SB and 80% for HES. Hemoglobin concentration was 10.4 g/dL with SB, 7.5 (6.8 g/dL in red blood cells and 0.9 g/dL in plasma) with MalPEG-Hb, and 7.5 g/dL with HES, leading to tissue Po(2) of 19, 8, and 5 mm Hg respectively. Calculations of oxygen extraction show that 0.9 g/dL of MalPEG-Hb increased oxygen extraction per gram of red cell hemoglobin in the tissue analyzed compared with SB. These measurements correlate well with a systemic indicator of recovery, base excess, 5.4 +/- 4.7 (MalPEG-Hb), 1.7 +/- 3.8 (SB), and -0.3 +/- 5.7 (HES). CONCLUSION The presence of 0.9 g/dL of high oxygen affinity MalPEG-Hb improves microvascular blood flow and oxygen transport during shock to a significantly greater extent than that attainable with blood or HES.
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Affiliation(s)
- Reto Wettstein
- Department of Bioengineering, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA.
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Ball J, Venn R, Williams G, Forni L. 22nd International Symposium on Intensive Care and Emergency Medicine, Brussels, Belgium, 19-22 March 2002. Crit Care 2002; 6:264-70. [PMID: 12133191 PMCID: PMC137453 DOI: 10.1186/cc1502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Jonathan Ball
- Department of Anaesthesia & Intensive Care, St George's Hospital Medical School, University of London, UK.
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Abstract
Concerns about the infectious and immunosuppressive risks of allogeneic blood products persist, and the increased disproportion of blood donation and consumption has reinforced the search for alternative erythrocyte transfusion strategies in recent years. With the absence of problems such as nephro-toxicity, increased colloid osmotic pressure and sudden renal clearance, modern haemoglobin based oxygen carriers (HBOC) have shown their effectiveness and tolerability in numerous animal and several clinical studies. HBOC can be infused without prior cross-matching and are now available as stable formulations with long shelf-life. Most clinical studies have been performed with human cross-linked haemoglobin (DCLHb) but all trials were stopped two years ago because of an increased mortality in two clinical trials in patients who received DCLHb after stroke and multiple injury shock. However, experimental trials in animals are in progress with DCLHb and recombinant human haemoglobin. In contrast, Phase III studies with polymerised bovine haemoglobin (HBOC-201) are finished or currently under evaluation showing that infusion of HBOC-201 can avoid or reduce allogeneic blood transfusion needs in specific peri-operative settings. As a consequence, HBOC-2001 was actually approved for treatment of peri-operative anaemia in elective adult surgical patients in South Africa. Other human or bovine haemoglobin solutions are currently being investigated in different clinical studies in cardiac surgery patients, sepsis and tumour patients. More recent investigations have shown that HBOC are not only simple erythrocyte transfusion substitutes but highly effective oxygen donators in terms of tissue oxygenation. HBOC open the door for a new therapeutic strategy: plasmatic oxygen delivery with physiological concentrations of inspired oxygen. In specific situations (e.g., ischaemia or arterial stenosis) HBOC have advantages over red blood cells because they can reach post-stenotic or poorly perfused tissues with the plasma stream, where erythrocytes are not able to pass. In addition to significant plasmatic oxygen transport, HBOC also enhance tissue oxygenation because of the facilitated oxygen release by HBOC and from remaining erythrocytes. Further studies will show, if the outcome of patients with impaired perfusion (e.g., stroke or myocardial infarction) can be improved by prophylactic or therapeutic application of HBOC. Whenever these formulations are globally launched, they will find differential indications as potent oxygen-delivering drugs in addition to the globally recognised goal of red cell substitutes in cases of bleeding.
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Affiliation(s)
- T Standl
- Dept. of Anesthesiology, University Hospital Hamburg-Eppendorf, Martini Strasse 52, Germany.
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