부산대학교 도서관

A 95-year-old female patient suffering from hypertension and chronic renal failure has been visiting the Internal Medicine Department of our hospital since 20XX - 2. She demonstrated hypoxemia, as shown by her percutaneous oxygen saturation of the peripheral artery (SpO2) of 86% on a vital sign check in August 20XX. She had no significant cardiac or pulmonary symptoms. Further arterial blood gas analysis using ABL800 FLEX (Radiometer Co., Ltd., Tokyo) did not yield data on the partial pressure of arterial oxygen (PaO2). Thus, the arterial saturation (SaO2) and PaO2 values were considered to be inappropriately correlated, and hemoglobinopathy was suspected because no significant respiratory or circulatory abnormality leading to hypoxemia was observed. Finally, genetic testing disclosed a low-affinity abnormal variant or Hb Yuda: codon 130 GCT(Ala)→GAT(Asp) at the α2-globin gene. As in this case, when we encounter a low SpO2 value that does not match clinical symptoms, SaO2 should be confirmed by arterial blood gas analysis. If PaO2 is higher than that expected from the SaO2 level, hemoglobinopathy of the low-affinity variant should be suspected.