Oxygen-carrying blood substitutes: a microvascular perspective

Area of Science:

• Biomedical Engineering
• Hematology
• Emergency Medicine

Background:

• Hemoglobin (Hb) is crucial for oxygen transport, but natural sources are limited.
• Blood substitutes aim to overcome shortages in transfusional blood availability.
• Previous efforts focused on replicating oxygen-carrying capacity.

Purpose of the Study:

• To develop a blood substitute that addresses limitations of natural hemoglobin supply.
• To improve resuscitation capacity and tissue metabolism during hemorrhage.
• To tailor blood substitute properties for microvascular function over oxygen delivery.

Main Methods:

• Understanding oxygen delivery in microcirculation and consequences of reduced oxygen-carrying capacity.
• Developing high-viscosity hemoglobin solutions with high oxygen affinity.
• Focusing on maintaining microvascular perfusion and shear stress.

Main Results:

• High-viscosity Hb solutions with high oxygen affinity can maintain microcirculation.
• This approach prioritizes microvascular function and perfusion during hemorrhage.
• It supersedes the sole restoration of oxygen-carrying capacity in hemorrhage treatment.

Conclusions:

• A viable blood substitute can be produced by multiplying natural hemoglobin supply.
• Tailoring properties for microvascular function is key for hemorrhage resuscitation.
• This strategy offers improved resuscitation capacity and tissue metabolism.