Neonatal Nurse Practitioner Practice Exam

A right shift in hemoglobin affinity results in what effect on oxygen?

1. Increased binding of oxygen to hemoglobin

2. Enhanced release of oxygen to tissues

3. Decreased availability of oxygen in circulation

4. Reduced oxygen levels in the lungs

The correct answer is: Enhanced release of oxygen to tissues

A right shift in hemoglobin affinity for oxygen is associated with an increased release of oxygen to tissues. This phenomenon occurs due to several factors, including increased levels of carbon dioxide, decreased pH (more acidic conditions), increased temperature, or increased levels of 2,3-bisphosphoglycerate (2,3-BPG) within red blood cells. Under these conditions, hemoglobin changes its structure, which enhances its ability to release oxygen rather than bind it tightly. When the affinity of hemoglobin is reduced, it facilitates oxygen availability to metabolically active tissues that require more oxygen, particularly in states of high metabolic demand. This is crucial in physiological scenarios, such as during exercise or in areas of the body where oxygen consumption is high. The other potential effects related to the other options—like increased binding of oxygen, decreased availability of oxygen in circulation, or reduced oxygen levels in the lungs—do not accurately represent the physiological outcome of a right shift in the hemoglobin-oxygen dissociation curve. Instead, a right shift emphasizes oxygen delivery rather than retention.