In ER w/ numb cheek+ arm, pallor. CBC + EKG normal. Oximeter showed 99% sat. BUT venous gas blood O2 saturation LOW at 0.34 (ref. Range 0.5-0.8). WHY?

Extraction or anemia. The oximeter only shows the amt of oxygen binding of the existing hemoglobin in the ARTERIES. JUST BECAUSE UR SATS R FINE DOESN'T MEAN EVERYTHING IS FINE. This is a common mistake even docs make. In ur case, the VENOUS blood has lower O2 content. It cd mean the body is using up more O2 (more extraction) d/t infx,, vascular probs, smoking, etc. Or u cd be anemic. Less Hgb = lower O2 content. TTYD!