title: Oxygen gas-filled microparticles provide intravenous oxygen delivery.
abstract: We have developed an injectable foam suspension containing self-assembling, lipid-based microparticles encapsulating a core of pure oxygen gas for intravenous injection. Prototype suspensions were manufactured to contain between 50 and 90 ml of oxygen gas per deciliter of suspension. Particle size was polydisperse, with a mean particle diameter between 2 and 4 μm. When mixed with human blood ex vivo, oxygen transfer from 70 volume % microparticles was complete within 4 s. When the microparticles were infused by intravenous injection into hypoxemic rabbits, arterial saturations increased within seconds to near-normal levels; this was followed by a decrease in oxygen tensions after stopping the infusions. The particles were also infused into rabbits undergoing 15 min of complete tracheal occlusion. Oxygen microparticles significantly decreased the degree of hypoxemia in these rabbits, and the incidence of cardiac arrest and organ injury was reduced compared to controls. The ability to administer oxygen and other gases directly to the bloodstream may represent a technique for short-term rescue of profoundly hypoxemic patients, to selectively augment oxygen delivery to at-risk organs, or for novel diagnostic techniques. Furthermore, the ability to titrate gas infusions rapidly may minimize oxygen-related toxicity.
authors: Department of Cardiology, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA. john.kheir@childrens.harvard.edu
authors: John N
authors: JN
authors: Kheir
authors: Laurie A
authors: LA
authors: Scharp
authors: Mark A
authors: MA
authors: Borden
authors: Edward J
authors: EJ
authors: Swanson
authors: Andrew
authors: A
authors: Loxley
authors: James H
authors: JH
authors: Reese
authors: Katherine J
authors: KJ
authors: Black
authors: Luis A
authors: LA
authors: Velazquez
authors: Lindsay M
authors: LM
authors: Thomson
authors: Brian K
authors: BK
authors: Walsh
authors: Kathryn E
authors: KE
authors: Mullen
authors: Dionne A
authors: DA
authors: Graham
authors: Michael W
authors: MW
authors: Lawlor
authors: Carlo
authors: C
authors: Brugnara
authors: David C
authors: DC
authors: Bell
authors: Francis X
authors: FX
authors: McGowan
mesh_terms: D000818:Animals; D005260:Female; D007275:Injections, Intravenous / Q000379:methods*; D046529:Microscopy, Electron, Transmission; D010100:Oxygen / Q000008:administration & dosage*; D010316:Particle Size; D011817:Rabbits
chemical_list: D010100:Oxygen