How does altitude or smoking affect pulse oximeter readings?
海拔高度或吸烟如何影响脉搏血氧计读数？
Altitude can affect oximeter readings because oxygen concentration in the air decreases at higher altitudes. Smoking can lead to lower oxygen saturation levels due to carbon monoxide in the blood, which pulse oximeters cannot differentiate from oxygen.
海拔高度会影响血氧计读数，因为海拔越高，空气中的氧气浓度就越低。由于血液中存在一氧化碳，吸烟会导致血氧饱和度水平降低，而脉搏血氧计无法将其与氧气区分开来。