Oxygen–hemoglobin dissociation curve

Oxyhaemoglobin dissociation curve

File:Oxygen-hemoglobin dissociation curve.png

Oxygen-hemoglobin dissociation curve

File:The Oxy-Hemoglobin Dissociation Curve.png

The Oxy-Hemoglobin Dissociation Curve

Error creating thumbnail:

Oxy-Hemoglobin

Oxyhaemoglobin dissociation curve

Fetal hemoglobin chart

The oxygen–hemoglobin dissociation curve is a graphical representation of the relationship between the partial pressure of oxygen (pO2) and the hemoglobin saturation (SaO2). This curve is crucial in understanding how oxygen is transported in the blood and delivered to tissues throughout the body.

Description

The curve is typically sigmoidal (S-shaped), reflecting the cooperative binding of oxygen to hemoglobin. As the partial pressure of oxygen increases, hemoglobin becomes increasingly saturated with oxygen. The steep portion of the curve indicates that small changes in pO2 result in significant changes in hemoglobin saturation, which is essential for efficient oxygen delivery to tissues.

Factors Affecting the Curve

Several factors can shift the oxygen–hemoglobin dissociation curve to the right or left, affecting oxygen binding and release:

• pH: A decrease in pH (acidosis) shifts the curve to the right, enhancing oxygen release to tissues (Bohr effect). Conversely, an increase in pH (alkalosis) shifts the curve to the left, reducing oxygen release.
• Carbon dioxide (pCO2): Increased levels of carbon dioxide shift the curve to the right, while decreased levels shift it to the left.
• Temperature: Higher temperatures shift the curve to the right, while lower temperatures shift it to the left.
• 2,3-Bisphosphoglycerate (2,3-BPG): Increased levels of 2,3-BPG shift the curve to the right, facilitating oxygen release.

Clinical Significance

Understanding the oxygen–hemoglobin dissociation curve is vital in various clinical settings, including anesthesia, critical care, and pulmonology. It helps in assessing the oxygenation status of patients and in making decisions regarding oxygen therapy and ventilatory support.

Related Pages

• Hemoglobin
• Oxygen transport
• Bohr effect
• Hematology
• Pulmonology