After entering the ICU, the subjects who meet the standards will undergo a full-body physical examination and basic vital signs assessment and monitoring, which mainly include specialized examinations of the nervous system, multimodal brain function testing, respiratory system monitoring and management, hemodynamic monitoring, and APACHEⅡ Score, GCS score, and perform routine general circulation, breathing management, sedation and analgesia management, temperature management, osmotic pressure management, lumbar puncture pressure measurement
Observe the changes of TCD/TCCD spectrum shape before and after lumbar puncture in patients with severe neurological disease.~Discuss the TCD/TCCD spectrum shape and parameters of cerebral arteries and neurocritical patients Correlation of intracranial pressure.