Causes of Delirium
Being confused because of an acute medical condition is not “failing to cope!”, ‘Failure to cope’ usually means ‘failure on the part of the physician to make an adequate diagnosis’!
The acute confusional state is merely the symptom of the underlying condition. It is the Emergency physician’s job to diagnose the underlying condition.
Almost any medical illness, intoxication, or medication can cause delirium. Delirium is often multifactorial in etiology and each potential cause should be investigated. The cause of a geriatric delirium cannot always be identified. Failure to find a cause does not mean that delirium is not present, but that the cause has yet to be determined.
- Infections (Think PUS: pneumonia, urinary, skin/soft tissue)
- ACS (often does not present with chest pain – the elderly are more likely to complain of “weakness” dyspnea or as being “just not themselves”),
- Hepatic encephalopathy
- Fluid/electrolyte abnormalities (hypo-/hyper-natremia, hypoglycemia, hyper/hypocalcemia)
Infections are the most commonly encountered cause of geriatric delirium.
- Even seemingly non-psychotropic meds
- Accidental or intentional discontinuation of any medications (even seemingly non-psychotropic meds)
- Alcohol, sedative hypnotics. OTC
- Subdural hematoma – occult traumatic or spontaneous
- Seizures – nonconvulsive statis, postical
- Hypertensive encephalopathy
Mnemonics for Causes of Delirium
To reiterate: almost any medical illness, intoxication, or medication can cause delirium. Delirium is often multifactoral in aetiology and each potential cause should be investigated.
Below are some mnemonics for remembering causes of delirium.
I Watch Death Mnemonic
I– Infections – PUS, pneumonia, urinary, skin/soft tissue, CNS
W– Withdrawl – often unintentional, from alcohol, sedatives, barbiturates
A– Acute metabolic changes – altered pH, hypo/hyper Na+ Ca++, acute liver or renal failure
T– Trauma – brain injury, subdural hematoma
C– CNS pathology – post-ictal, stroke, tumour, brain mets
H– Hypoxia – CHF, anemia
D– Deficiencies – thiamine, niacin, B12 (e.g. chronic G and T alcoholics)
E– Endocrinopathies – hypo-/hyper-cortisol, hypoglycemia
A– Acute vascular – hypertensive encephalopathy, septic hypotension
T– Toxins and Drugs – especially anti-cholinergics, opioids, benzodiazepines
H– Heavy metals
D– Drugs, dehydration, detox, deficiencies, discomfort (pain)
E– Electrolytes, elimination abnormalities, environment
L– Lungs (hypoxia), liver, lack of sleep, long ED stay
I– Infection, iatrogenic events, infarction (cardiac, cerebral)
R– Restraints, restricted movement/mobility, renal failure
I– Injury, impaired sensory input, intoxication
U– UTI, unfamiliar environment
M– Metabolic abnormalities (glucose, thyroid), metastasis (brain), medications
Discussion: Causes of Delirium
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Delirum can be hard to find an underlying cause. Going through a good family history, etc. will be important
i watch death
The I watch death one is so long is not really helpful
Long hospital stay
continuing to learn more info.
Poniant and timely. Provided a whole new dynamic with respect to geriatric emergency medicine. Well received, will definitely incorporate in my assessment of the elderly with-in my scope of practice.
very helpful mnemonics
– a thorough history with help from family will provide a better picture when investigating a delirium
agree for sure
Obtain history, listen to patient,
Causes of delirium can very from patient to patient but most common is a source of infection like a uti or even skin or wound infection. other more causes like stroke or cardiac tend to be more symptomatic and acute.
very cleaver way to word things
very useful mnemonics
The input of the family plays a significant role in he diagnosis of a delirium pt. The mnemontics helps out a lot. I like I watch death it helps out a lot in the ED setting.
team work is importent
Great review. Important to remember that delirium can be many things and reversible. Its important to dig your heels in and figure out what it is. I can not say enough about getting a full assessment.
Often UTI or polypharm
I enjoyed this
Question — it says: Infections are the most commonly encountered cause of geriatric delirium. Then it says: Medications are the most common reversible causes of geriatric delirium.
Which is it? Aren’t infections reversible?
UTIs are common
home care Para medicine may help with trips to er
I like the mnemonics but that’s a lot of info to remember!
yes it is
really useful to know
This is helpful
so very useful
love these mnemonics
Discussion also helpful
Fantastic way to present the information- makes it much easier to identify and remember!
helpful review and mnemonics for assessing geriatrics in the community health care team.
Great info to have-especially if working closely with the elderly.
The acronyms are the most useful part of the course so far. Will definitely use these
better to admit for safety concern then to come back with worse condition if missed.
These are very helpful
I WATCH DEATH. some valuable things to assess there.
The mnemonics are helpful. The short rule I learned was “Bugs and Drugs” as being the most common reasons for delirium
Love the mnemonics I feel like I’m back in med school.
I like the acronyms
“i watch death” is a pretty interesting and detailed way to rmb causes of dementia
i agree, it goes too show how important assessment is in order to identify these possibilities
HELFUL, GREAT INFORMATION TO USE DAILY WHEN DEALING WITH PATIENT.
helpful and easy to remember
can’t say I have seen all these before
helpful list of reasons may cut down on re-visits
great memory aids…
Important to remember the wide differential. Just recently, I assessed a patient in the ED with acute onset delirium with no real neurological deficits, CT ended up confirming acute stroke.
Great way to remember
As a paramedic and an ER nurse I love and depend on mnemonics.
Wow – “I WATCH DEATH” – I won’t forget that one!
Excellent review and mnemonics
Memorizing mnemonics is pointless (except maybe for exam purposes). How is anyone going to remember that “A” stands for “acute metabolic abnormalities”?
Instead, use a checklist routinely.
checklist is a great idea. Agree that these mnemonics are too long and cumbersome to be clinically useful.
Many potential causes which may require alot of investigations to rule out specific causes
excellent way to remember
While mnemonics are often useful, a good clinical history should guide your thought process and keep you out of the ‘weeds’, thus avoiding excessive testing without cause/indication.
The most common cause may be a UTI in women but not necessarily in men. Mnemonics provide the medical provider with the opportunity to be thorough.
I’m curious about your thoughts on women vs. men. Certainly there are many older men who present to ED with urinary retention, often due to obstruction, but possibly with co-infection present.
The meneumonics are helpful
Yet another good screening tool and prompt for specific line of questioning
Causes of delirium are so widespread. I do think that menomics are a useful way of remembering the lists, but I don’t think they should be used directly on patients – often it is more helpful just to take a history and listen carefully to the patients and their relatives, and then go back to your mnemonic and check that you’ve covered the possibilities.
use a mnemonic
often multifactorial even if infection present
ever think in the possible easy reversible causes of delirium
think of infectious diseases and dehydration
Most common cause I see is UTI
common cause is UTI
We find frequently in the ed that UTIs are a common cause of delirium
I agree with Aghazam. Too often I see investigations and dispositions based on the cc without a proper Hx and PE being done.
Collaboration of the team to care for these patients is imperative.
collaborative history from family members will be important
Whenever an elderly patient in ER we shoulder screen for IWATCHDEATH alway,that will give us a good screening tool to provide enormus information about those patients.
When you think it is delirium best to go through a mnemonic of your choice so as not to miss anything and at times there several causes at play.
Obtaining a decent history is the cornerstone to determining the patient’s baseline and potenial underlying causes. Triage note/”CC” may be very different from the real story.
research has proven quality geriatric care takes a team of various health care professionals
Diagnosing the underlying cause of delirium in home-bound seniors can be challenging, but trips to ER can often be averted.