PubMed Health⌕ Search

PubMed · 11336435

Oxygen therapeutics--current concepts.

Abstract

PURPOSE: In an effort to develop agents that enhance the oxygen-delivery capability of blood without the risks associated with allogeneic blood transfusions, several products are undergoing development and clinical trials. These oxygen transport agents can be divided into two main groups, perfluorocarbon (PFC) emulsions and modified hemoglobin solutions. SOURCE: Articles from the literature on the development and clinical trials of oxygen therapeutic agents were reviewed. PRINCIPAL FINDING: PFCs are synthetic fluorinated hydrocarbons that increase dissolved oxygen in the fluid phase of the blood without binding the oxygen molecule. They enhance oxygen delivery significantly and may be used to augment the technique of intraoperative autologous donation. Two PFC products have been tested in Phase III clinical trials. Hemoglobin-based oxygen carriers (HBOCs) are either cross-linked or microencapsulated hemoglobin molecules. Modification of the human hemoglobin molecule with intra- and inter-molecular cross-linking eliminates renal toxicity and improves the oxygen dissociation characteristics of the molecule. These modifications are necessary because stroma-free hemoglobin (Hb) does not release oxygen in the physiologic range and dissociates into dimers which can be rapidly filtered by the kidney, leading to renal toxicity. In addition to human Hb, bovine hemoglobin is another source of raw material for HBOC products. Recombinant human Hb has also been produced, using an E. coli expression system, for HBOC manufacturing. Four cross-linked hemoglobin products have been tested in Phase III clinical trials. CONCLUSION: While no product has yet been approved for clinical use, preliminary studies with oxygen therapeutics show promising results, with effective oxygen carrying capacity and acceptable side effect profiles. In the future, the formation of a hybrid product which combines the best features from several of the products currently undergoing development may yield the ideal oxygen therapeutic agent.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

S E Hill. 2001. Oxygen therapeutics--current concepts.. https://pubmed.ncbi.nlm.nih.gov/11336435/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Rapid desensitization protocols for patients with cardiovascular disease and aspirin hypersensitivity in an era of dual antiplatelet therapy.

OBJECTIVE: To review the available protocols for rapid desensitization of patients with aspirin hypersensitivity and apply the data for use in patients with cardiovascular disease who would benefit from the dual antiplatelet therapy. DATA SOURCES: A literature search was conducted via MEDLINE from 1966 to December 2006. Main search terms included: aspirin sensitivity, aspirin allergy, aspirin desensitization, aspirin-induced asthma, aspirin therapy, and aspirin intolerance syndrome. STUDY SELECTION AND DATA EXTRACTION: Articles describing rapid aspirin desensitization protocols were selected for review. Literature pertaining to aspirin hypersensitivity, drug desensitization, and the use of aspirin and dual antiplatelet therapy was also examined. Three rapid desensitization protocols were identified and evaluated. DATA SYNTHESIS: While landmark studies demonstrated that dual antiplatelet therapy with aspirin and clopidogrel significantly reduces mortality and morbidity in acute coronary syndromes and coronary stenting, patients with aspirin hypersensitivity are frequently managed with clopidogrel alone with no supporting data. Approximately 10% of the population experiences hypersensitivity to aspirin, which can manifest as asthma exacerbations, rhinorrhea, angioedema, urticaria, and anaphylaxis. The hypersensitivity reaction is mediated through aspirin-directed antibodies or by excessive leukotriene production. The desensitization process involved depletion of these mediators, as well as down-regulation of leukotriene receptors. Two groups of investigators developed rapid protocols to desensitize patients with aspirin hypersensitivity safely and effectively. The rapid protocol developed by Wong provides benefits over other protocols with its low starting dose and completion in less than 3 hours, low incidence of adverse effects, and high success rate in aspirin desensitization. CONCLUSIONS: The Wong protocol is an attractive option for the rapid desensitization of patients requiring dual antiplatelet therapy with aspirin and clopidogrel in the perimyocardial infarction period.

Aspirin↗