Oxygen dissociation curve shifts to right in the following condition:

Most forms of anemia do not affect the oxyhemoglobin dissociation curve if the association of oxygen and hemoglobin is expressed as percent saturation. It is the amount of hemoglobin that decreases, not the percent saturation or even the aerial PO2. The aerial content of oxygen, however, in milliliters of oxygen per 100 mL of blood, is reduced, because the decreased amount of hemoglobin per 100 mL of blood decreases the oxygen-carrying capacity of the blood. Anemia severe enough to increase tissue anaerobic metabolism causes metabolic acidosis and a rightward shift of the oxyhemoglobin dissociation curve. Ref: Levitzky M.G. (2013). Chapter 7. Transpo of Oxygen and Carbon Dioxide in the Blood. In M.G. Levitzky (Ed), Pulmonary Physiology, 8e.