Hematological alterations after acute exposure to hyperbaric oxygen in rats

Area of Science:

• Physiology
• Biomedical Engineering

Background:

• Acute hyperbaric oxygen (HBO) exposure is known to increase hematocrit.
• The effects of HBO on blood viscosity and oxygen delivery require further investigation.

Purpose of the Study:

• To investigate the impact of acute hyperbaric oxygen (HBO) exposure on blood viscosity and oxygen delivery in Sprague-Dawley rats.
• To assess changes in blood parameters influencing viscosity post-HBO exposure and recovery.

Main Methods:

• Three groups of rats were used: control (CON), immediate post-HBO exposure (HBO), and 24-hour recovery post-HBO (REC).
• Whole blood, plasma, and red blood cell (RBC) suspension viscosity were measured.
• Blood parameters including plasma colloid oncotic pressure, platelet count, fibrinogen, and leukocytic count were evaluated.

Main Results:

• Whole blood viscosity significantly increased in both HBO and REC groups compared to CON (P < 0.05).
• Plasma and RBC suspension viscosity showed no significant changes.
• A significant decrease in oxygen delivery index was observed in the REC group (P < 0.05).
• Increased plasma colloid oncotic pressure, platelet count, fibrinogen concentration, and total leukocytic count were noted in HBO and/or REC groups.

Conclusions:

• Acute HBO exposure elevates whole blood viscosity, an effect sustained after 24-hour recovery.
• HBO exposure alters blood parameters, potentially contributing to increased viscosity and reduced oxygen delivery.
• Further research is needed to understand the long-term implications of HBO-induced hemorheological changes.