blood O↓2 difference

例句：

1. 1. The patient's blood oxygen saturation is critically low.
   患者的血氧饱和度严重偏低。
2. 2.The oxygen tension in the room was too low for the child to breathe properly.
   房间里的氧气浓度太低，孩子无法正常呼吸。
3. 3.The doctor measured the patient's blood oxygen saturation and oxygen tension before administering the treatment.
   在给患者治疗之前，医生测量了患者的血氧饱和度和氧气张力。