Shift to right of oxygen dissociation curve is caused by all, EXCEPT:

Three impoant conditions affect the oxygen-hemoglobin dissociation curve: the pH, the temperature, and the concentration of 2,3-biphosphoglycerate (BPG; 2,3-BPG). A rise in temperature or a fall in pH shifts the curve to the right. When the curve is shifted in this direction, a higher PO2 is required for hemoglobin to bind a given amount of O2. Conversely, a fall in temperature or a rise in pH shifts the curve to the left, and a lower PO2 is required to bind a given amount of O2. A convenient index for comparison of such shifts is the P50, the PO2 at which hemoglobin is half saturated with O2. The higher the P50, the lower the affinity of hemoglobin for O2. Ref: Ganong's Review of Medical Physiology 23rd edition, Chapter 36.