Neonatal Nurse Practitioner Practice Exam

What is an outcome of decreased hemoglobin affinity for oxygen?

1. Increased oxygen saturation in hemoglobin

2. Facilitated oxygen release to tissues

3. Reduced oxygen delivery to the lungs

4. Increased resistance to oxygen binding

The correct answer is: Facilitated oxygen release to tissues

Decreased hemoglobin affinity for oxygen leads to a physiological condition where hemoglobin is more willing to release its bound oxygen to the tissues. This phenomenon is particularly important in areas of the body where oxygen is needed most, such as in metabolically active tissues that are producing carbon dioxide and other metabolites. When the affinity of hemoglobin for oxygen decreases, hemoglobin changes its configuration in response to the local environment, which often includes increased concentrations of carbon dioxide, lowered pH (increased acidity), and elevated temperatures that are common in active tissues. This is known as the Bohr effect, where the presence of these factors facilitates the unloading of oxygen. Thus, a decreased affinity ensures that hemoglobin effectively transports oxygen from the lungs to areas of the body where it is critically needed, enhancing overall oxygen delivery to tissues that require it for metabolism and energy production.