Significance of hemoglobin concentration in determining blood CO2 binding capacity in critical illness

This study was performed to provide simplified quantitative evidence of the impact of hemoglobin concentration on bloodCO2 binding and transport capacity. Linear regression equations were obtained for gas analyses data obtained from 85 surgical patients with sepsis and various degrees of illness. Venoarterial CO2 concentration differences were calculated by a complex procedure, and then simplified equations were derived to highlight the impact of hemoglobin concentration on blood CO2 binding and the Haldane effect. The results showed that, although in normal conditions the impact of hemoglobin concentration is less evident, it becomes relevant in extreme conditions, also protecting against venous and tissue hypercapnia and acidosis.