Delirium Flashcards
Define delirium?
- Disturbance in attention
- Change in cognition, e.g: memory deficity, disorientation, language disturbance, perceptual disturbance
- Develops over a SHORT PERIOD (usually hours-days) and tends to FLUCTUATE during the day
Distinguishing between delirium and dementia?
Delirium develops over a short period of time, unlike dementia
Causes of delirium?
Always MULTI-FACTORIAL
Direct physiologic consequences of:
- A general medical condition, e.g: infection, MI, electrolyte imbalance,
- Intoxicating substances
- Medications
- Multi-factorial
It often represents an atypical presentation of an acute medical illness, e.g: MI in an older patient
Consqeuences of delirium?
Prolonged hospital stay and thus more hospital-acquired complications, e.g: falls and pressure sores
Increased mortality
Increased incidence of subsequent dementia; in fact, dementia itself increases the risk of delirium, due to the initial lower level of cognition, creating a cycle
Types of delirium?
Hyperactive delirium (easier to diagnose) - wandering, agitated and restless patients
Hypoactive delirium - withdrawn, apathetic, sleepy and slow patients, who are often missed; this has higher mortality
Hypoactive delirium is most common but it can also be mixed
Differences in the features of dementia, delirium and depression?
Pathophysiology of delirium?
Poorly understood; there is variable derangement of multiple neurotransmitters, part. ACh
Clear factors are direct toxic insults to the brain, e.g: drugs, hypoxia, low Na+ and low glucose
Other potential factors include aberrant stress responses, e.g: cortisol (hospital is a stressful environment), PGs, cytokines, serum cholinesterase
What is a common misdiagnosis when an older patient is confused?
UTI (confusion does not automatically mean this)
Steps in developing delirium?
Often a patient who has predisposing factors, and is at risk of delirium, is exposed to precipitating factors and develops delirium
Precipitating factors for delirium?
Drugs and intoxicating substances, e.g: alcohol
General medical issues, e.g: infections (pneumonia, UTI, etc) hypoxia, constipation, MI, urinary retention
Electrolyte imbalance, glucose issues
Being in an unfamiliar environment
Pain and irriation, e.g: fractured hip, urinary catheterisation
Fever (may also cause delirium in children)
• Dehydration
4 hallmarks of delirium?
- Acute and fluctuating
- Inattention
- Altered level of consciousness
- Disorganised thinking
Diagnostic tool for delirium?
CAM
4AT scoring system
What do the 4AT scores mean?
4/above = possible delirium +/- cognitive impairment
1-3 = possible cognitive impairment
0 = delirium or severe cognitive impairment unlikely but delirium is still possible if the info under 4. is incomplete
Describe the Confusion Assessment Method (CAM) for the diagnosis of delirium
- Acute change in mental status and fluctuating mental status over the course of the day
AND
- Inattention - use backward months test or digit span test (<7 is abnormal)
AND
- Disorganised thinking, e.g: rambling
OR
- Altered LoC, i.e: hyperalert/irritable OR drowsy/sleepy
Management of delirium?
Identify and correct all underlying causes:
- Check bloods, correct electrolytes and glucose
- Check for and correct hypoxia
- Ensure good hydration
- Stop drugs with neurotoxic effects
- Relieve pain (beware of too much opioid)
- Treat constipation
- Septic screen
- ECG (rule out MI/arrhythmia)
- Avoid a urinary catheter, unless in retention
- Consider alcohol withdrawal
