Which of the following is NOT a sign or symptom of CNS oxygen toxicity?

Extreme fatigue is indeed not typically recognized as a sign or symptom of CNS oxygen toxicity. Central Nervous System (CNS) oxygen toxicity primarily presents with more acute and identifiable neurological symptoms, which include nausea and vomiting, irritability, and visual disturbances.

Nausea and vomiting can occur due to the physiological response to high levels of oxygen, which can lead to a range of disturbances in the body. Irritability may arise as the nervous system becomes overstimulated by elevated oxygen levels. Visual disturbances, such as tunnel vision or changes in perception, reflect how oxygen affects neural pathways related to sight.

In contrast, extreme fatigue does not directly correlate with these acute reactions and is more commonly associated with general exhaustion or other conditions. Therefore, it distinguishes itself from the well-documented symptoms associated with CNS oxygen toxicity. Understanding the specific symptoms associated with conditions like CNS toxicity is crucial for effective recognition and response during scenarios involving high oxygen exposure.