For inexperienced providers in the emergency department, the evaluation of the altered patient can be difficult. These patient are often unable to provide an accurate history and one must often rely on the information obtained from family, friends, pre-hospital care providers or nursing home staff. The approach to altered mental status can seem overwhelming when one considers the hundreds of potential causes.
In an attempt to provide some helpful tips for those new to emergency medicine, I will be breaking down the approach to altered mental status into multiple, “bite-size” 60-Second posts.
For some, mnemonics can be a helpful way to remember lists of items. No ‘one’ mnemonic is all inclusive, or better than another. Use whatever helps you remember and learn the basics.
Here are some mnemonics commonly used to often systematically break-down the possible causes for Altered Mental Status :
Alcohol/Acidosis (metabolic disorders)/Arrhythmia (any cardiac cause)
Trauma/Temperature (hyperthermia/hypothermia)/Thiamine (Wernicke)
Poisoning (any medication)/Psychiatric
Stroke/Seizure (or post-octal state)/Syncope/Space occupying lesion/Shunt (VP) Malfunction
Drug Intoxication or Withdrawal: Opiates, Benzos, illicit drugs, Ethanol intoxication or withdrawal
Infection: either Primary CNS (meningitis/encephalitis) or systemic infection (pneumonia, UTI)
Primary Neurologic: (Stroke, Seizure intracranial hemorrhage)
Psychiatric: diagnosis of exclusion
Systemic Disease: Cardiovascular (hypotension, low cardiac output), Pulmonary (hypoxia), Renal (uremia, hypo/hypernatremia, hypercalcemia), Liver (hepatic encephalopathy), Endocrine (hypo/hyperglycemia, thyroid dysfunction)
Or you can try to separate common causes into containers of ‘like items’…..
Brain: Glucose, Oxygen, Blood
Metabolic: Electrolytes, Ammonia
Toxins: Ethanol, Opiates, Cocaine
Infectious: Peripheral vs. Central
Structural: CNS lesion (blood, tumor)
Hopefully some of you will find some of these mnemonics helpful in your initial approach in considering the most common causes of altered mental status.
Watch for Altered Mental Status for DUMMIES – Part II – coming soon