Brain injured patients are at high risk of pain due to the illness itself and a variety of nociceptive procedures in intensive care unit. Since the disorder of consciousness, speech, and movement, it is usually difficult for them to self-report the presence of pain reliably. The Critical-Care Pain observation Tool (CPOT) has been recommended for clinical use in the critically ill patients when self-report pain is unavailable. Besides, it seems that the bispectral index (BIS), a quantified electroencephalogram instrument, can be used for pain assessment along with the CPOT tool in some nonverbal critical ill patients (e.g., intubated and deep sedation). However, the validity and reliability of CPOT and BIS for pain assessment in brain injured patients are still uncertain so far. So the aim of this research is to investigate the value of CPOT and BIS for pain evaluation in this specific patient group.

Inclusion Criteria:

• patients with brain injury and artificial airway

Exclusion Criteria:

• age under 18 years,
• quadriplegia,
• administration of paralytic medications within 24 hours,
• if the patient failed the quality test of BIS signal,
• impending death,
• be included in any other research.

Adult patients with brain injury and artificial airway