Abstract
A case of pseudohypoxemia due to acute leukemia is reported. A male patient was admitted with severe anemia and was diagnosed as having both myelodysplastic syndrome and left renal cancer. Respiratory failure occurred after renal tumor resection and led to disturbance of consciousness. After intubation, his consciousness became clear and a pulsoximeter indicated 98% O2 saturation. However, blood gas analysis at that time showed a PaO2 41mmHg and SaO2 79%.
Acute leukemia secondary to myelodysplastic syndrome was diagnosed because his white blood cell count was 257×103·mm-3. The partial oxygen pressure of arterial blood kept at room temperature was 103mmHg just after sampling and decreased to 85mmHg after 2 minutes, 69mmHg after 5 minutes, 52mmHg after 10 minutes, and 36mmHg after 30 minutes. When the white blood cell count decreased to less than 37×103·mm-3 during chemotherapy, a decay in oxygen tension was not observed. Thus, extreme leukocytosis secondary to leukemia can cause spurious hypoxemia. Special attention must be paid to blood gas analysis in patients with leukemia.
