Known proximate cause of condition
Cerebral unresponsiveness
Absence of<unk>  stem relexes (see below)
Apneic (see below)
Irreversible condition (+/- repeat exam in 6hrs)
Exclusion of complicating medical conditions:
Severe electrolyte abnormalities
Acid-base derrangement
Endocrine disturbance
Hemodynamic compromise, with age-adjusted vital sign "normals" in pediatric patients
Drug intoxication/poisoning
Core temperature < 32 C (90 F)
Locked-in syndrome
Guillain-Barre syndrome involving all peripheral and cranial nerves
Be aware of hospital or state regulations such as:
Two separate clinical exams performed by two different physicians at least one hour apart
Agreement of<unk>  between two physicians documenting findings from exam, apnea testing, confirmatory testing
Observation period between clinical exams varies when<unk>  determined in children < 1 year of age
2 mo - 1 yr, waiting period between exams should be at least 24 hours
7 days - 2 mo, waiting period should be at least 48 hours
No reliable criteria for children < 7 days
Severe electrolyte abnormalities
Acid-base derrangement
Endocrine disturbance
Hemodynamic compromise, with age-adjusted vital sign "normals" in pediatric patients
Drug intoxication/poisoning
Core temperature < 32 C (90 F)
Locked-in syndrome
Guillain-Barre syndrome involving all peripheral and cranial nerves
Two separate clinical exams performed by two different physicians at least one hour apart
Agreement of<unk>  between two physicians documenting findings from exam, apnea testing, confirmatory testing
Observation period between clinical exams varies when<unk>  determined in children < 1 year of age
2 mo - 1 yr, waiting period between exams should be at least 24 hours
7 days - 2 mo, waiting period should be at least 48 hours
No reliable criteria for children < 7 days
2 mo - 1 yr, waiting period between exams should be at least 24 hours
7 days - 2 mo, waiting period should be at least 48 hours
No reliable criteria for children < 7 days
Brain death
Spinal shock
Hemorrhagic shock
Neurogenic shock
Heat exhaustion
Heat stroke
Stroke 
Tumor lysis syndrome