I am not sure you need inflammation as an explanation. People in the ICU are there because they are extremely sick. Often they have problems with blood pressure

I am not sure you need inflammation as an explanation. People in the ICU are there because they are extremely sick. Often they have problems with blood pressure and oxygenation. This probably leads to neuron death. In addition, because they are getting checked on continuously they likely have poor sleep and loss of day-night cycles. I am not sure how you can differentiate between very sick people are in the ICU, and very sick people often have a lot of inflammation.