<prompt> Oxygen dissociation curve shifts to left in all except:AlkalosisHypercapniaFetal HbCO poisoning  <response>: When the O2 affinity for Hb is increased, the dissociation curve shifts to the left. O2 has less affinity for Hb which is in T-state. When Hb is snapped into R-state, O2 affinity for it increases. Increased affinity of O2 for Hbshift to the left Decreased Halkalosis Decreased PCO2 Decreased temperature Decreased 2,3-DPG HbF CO poisoning Stored blood 2,3-DPG decreases NO H2S bind to Hb; snap it into R-state 