 [ Symptoms ] can co2 levels of 73 or 74 mmhg during respiratory failure cause some form of brain damage like permanent short term memory loss [ Disease ] high co2 levels can be associated with low oxygen levels and can cause acidemia which can cause temporary or permanent nerve or brain damage it can cause dizziness delirium hallucinations etc and can be as fatal as coma or death you should be under proper medical management to prevent any sudden fatal symptoms hope this helps regards