What are the signs of an oxygen level drop below 8%?

The identification of blue lips and nausea as signs of an oxygen level drop below 8% highlights critical physiological responses to severe hypoxia. When oxygen levels fall significantly, such as to 8% or lower, the body begins to exhibit noticeable symptoms due to inadequate oxygen transport to tissues.

Blue lips, also known as cyanosis, indicate a lack of oxygen in the blood, leading to a bluish discoloration, particularly in areas with high capillary density. This visual cue is often associated with critical conditions of respiratory distress or severe hypoxemia, where the body is struggling to acquire sufficient oxygen.

Nausea may occur as the brain and body begin to react to the stress of poor oxygenation. In severe oxygen deprivation, metabolic processes are disrupted, which can lead to feelings of sickness and discomfort. This effect is often compounded by hypoxia's impact on the central nervous system.

In contrast, while options like rapid heartbeat, dizziness, severe headache, sleepiness, and confusion can indeed be symptoms of varying degrees of oxygen deprivation, they are less distinct indicators of such a dangerously low oxygen saturation level. Blue lips and nausea are more directly indicative of severe hypoxia, making them key signs to recognize in this critical context.