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Last updated: ACS (Acute Coronary Syndrome)
on September 06, 2010

Acute Confusional State

Key facts:


Authors: Damian Mayo and Kris Ghosh
Top Tips: Commonest cause is sepsis (urinary tract and chest). Not TIA/CVA. Don't forget encephalitis

Key differential diagnoses

Dementia (chronic confusion)
Learning difficulties
Hysterical confusion 

Key investigations

Glucose (BM), dipstick
O2 saturation ± ABG if low
FBC, ESR, CRP [Ref]
U+E, LFT/GGT, Bone, Glucose, ± B12/folate, TFTs, TPHA
BC, MSU
CXR ± CT head (± LP)

Key Treatment

OXYGEN high flow, if hypoxic
IV ANTIBIOTICS, if infected (if source unclear, IV BENZYLPENICILLIN 1.2 g qds + IV GENTAMICIN 5 mg/kg od)
Remove drug cause
± IV GLUCOSE, 20 mls 50%, if BG < 4 mmol/L
± Alcohol withdrawal regime, if appropriate
± O/IM HALOPERIDOL 2-10 mg (start as low as possible,
even 0.5 mg)

Key Management
Decisions

CT head (± LP) (encephalitis)

 

 


Background


First of all, ascertain whether the confusion is really acute; ie does the patient have chronic confusion (dementia)?; or is this acute on chronic confusion

Introduction

• An acute confusion state is a neuropsychiatric syndrome which is difficult to define but involves abnormalities of perception, thought and awareness levels. Patients may appear confused or 'not with it' when talking to them. It may be their family or carer who notice the confusion, alternatively
• It is very common, especially in the elderly, and not a benign syndrome. Many of these patients subsequently do not return to their baseline function and some even require long-term institutionalisation. 20% medical and surgical acute admissions have some confusion; 10% of elderly admissions primarily due to confusion (often due to drugs). 5% in-hospital mortality, 10% mortality (+25% functional decline) at 3 mths. 50% diagnosed dementia in 2y
• It can occur acutely or subacutely. Characteristically symptoms fluctuate
• Sepsis, drugs/alcohol (excess/withdrawal) and metabolic disturbance are the 'big 3' ie three commonest causes of an acute confusional state
• TIA/CVA rarely presents as confusion. But hyponatraemia is a common cause in the frail elderly
• First of all, check the blood glucose. Record Mental Test Score (MTS; partly as baseline)
• Removal from home can cause acute confusion. The skills are not to admit the frail elderly unless its necessary (or make their stay as short as possible), and accident prevention
• Pain and opiates can both cause confusion (think about post-op, especially post #NOF). Think about nursing issues and it's important to sedate only if essential. This is a good review: [Ref]

Medicolegal aspects

• Patients are vulnerable
• It is a common scenario for errors, eg missing the diagnosis and poor management. This is why it has the potential to rapidly become serious
• So, do a full examination, and a full set of bloods, BC, CXR, and CT head, if necessary
• Do not assume confusion is due to long-term dementia or learning difficulties, even in the elderly and those with learning difficulties. In other words, check previous level of function from relative/carer/home circumstances
Note: if this is not possible treat as acute confusion until proven otherwise; not doing this is medicolegally dangerous; do not go there; you need to make great efforts to find out their baseline mental state; ring family, GP, anyone; 2am, 2pm, anytime

Definitions

• Neuropsychiatric syndrome characterised by disorientation in time and place, impaired short-term memory, and impaired consciousness; occuring over hours/days, with a tendency to fluctuate over the course of the day
• Delirium = in addition, there are disorders of perception (hallucination, illusion, delusion)
• Importantly, confusion and delerium are reversible

DSM-IV Diagnostic Criteria for Delirium Due to a General Medical Condition (2000) 1. Disturbance of consciousness (ie, reduced clarity of awareness of the environment) with reduced ability to focus, sustain, or shift attention
2. A change in cognition (such as memory deficit, disorientation, language disturbance, or all 3), or development of a perceptual disturbance that is not better accounted for by a pre-existing, established, or evolving dementia
3. The disturbance develops over a short period of time (usually hours to days) and tends to fluctuate during the course of the day
4. There is evidence from the history, physical examination, or laboratory findings that the disturbance is caused by the direct physiological consequences of a general medical condition

Epidemiology

20% medical and surgical acute admissions have some degree of confusion; 10% of elderly admissions primarily due to confusion often due to drugs: [Ref] ; ie its very common, just ask the questions
Note: only 10% of admissions with confusion have a primary neurological problem (vs sepsis, drugs and metabolic; which are the most important groups of causes)

Causes

HIDEMAP (from GP notebook)
H = hypoxia (CCF, Respiratory Failure, ARF) + head trouble (head injury, SOL (SDH? Brain abscess?); meningitis; rarely .. encephalitis, cerebral malaria)
I = infection (UTI, chest, wound, line, post-op, neutropenic sepsis, especially if immunosuppressed)
D = DRUGS DRUGS DRUGS = recreational or prescribed, excess or withdrawal, eg: benzodiazepines, analgesics (especially opiates), Anticholinergics, Anticonvulsants, anti-parkinsonism medication, steroids
E = endocrine (hyper/hypoglycaemia, hypothyroidism (especially elderly))
M = metabolic (ARF, ALF, hypercalcaemia, hyponatraemia)
A = alcohol (excess or withdrawal) + anaemia (B12/folate deficiency)
3Ps = psychosis + postictal + postop (especially post #NOF; often multifactorial, eg septic, dry and drugs)
Notes: TIA/CVA does not usually present as confusion; steroids can cause 'steroid psychosis'
[Ref]

Risk factors

Dementia (ie worsening confusion)
Alcohol + recreational drugs
Recent surgery (especially neurosurgery); look on back of drug card

Symptoms

History has limited value

Key questions

Vital to get history from witnesses (relative, carer, ambulanceman):
Depression (?overdose); epilepsy; drug/medical history; recent head and neck infection (brain abscess); recent surgery (especially neurosurgery)
; cerebral shunt?
Note: pick up the phone if necessary. Remember, the 'poor historian' is you

Signs

Record mental test score (partly as baseline)
Note: if you are in a hurry, do at least the first three, ie is the patient orientated in time, place and person?. If they know the date, they are not confused
Look for needle tracks, and signs of head injury and alcohol
Check for bladder (retention can cause confusion in elderly)
Note: patient may be a danger to you (aggression or HIV/Hep B/C positive, ie wear gloves)

Investigation


First of all, check the blood glucose. Don't forget the '3 Treatable Ts' = Thyroid(hypo), TPHA + BTwelve deficiency

Blood

FBC, ESR, CRP
U+E, LFTs, GGT, Bone (?calcium), Glucose, B12/folate,TFTs, TPHA/VDRL
Note: don't forget the '3 Ts' (Thyroid(hypo), TPHA + BTwelve deficiency. Even though these are rare causes of acute confusion, they (and subdural haemorrhage) are 4 of the important reversible causes of chronic confusion ie dementia. In fact, many dementia clinics will not take a referral from a GP, unless those 4 things have been excluded
O2 saturation (± ABG, if low), BC
± CK, if has been on floor for long
± Thick/thin films (malaria)
± SLE serology

Other

Urinalysis: leucocytes? nitrites? (catheterise slowly if cannot get sample)
?Urinary toxin screen (overdose?)
MSU
CXR
(pneumonia, ?carcinoma if patient hyponatraemic)
AXR: ?constipation (can cause confusion in elderly)
CT head ± LP , if no obvious diagnosis, or not improving at 24 hrs

Key investigations

Glucose
CT head ± LP

Specialist investigation

EEG

Differential diagnoses

Learning difficulties, dementia (chronic confusion) - all easy to confuse (!)
Drunk
Deafness
Dysphasia/Dysarthria
Depression
Hysterical confusion
Bipolar disorder
Other psychoses eg schizophrenia

Treatment


Admitted or not, such patients are a danger to themselves, and others; ie the most important 'treatment' may be making them safe - so think about nursing issues

Treatment
(first line)

Drugs:
IV GLUCOSE 20 mls 50%, if BG < 4 mmol/L
Note: GLUCOSE increases risk of Wernicke's encephalopathy, so give IV PABRINEX first, if suspect patient is alcohol dependent and hypoglycaemic
IV PABRINEX 2 vials tds, if ?Wernicke's or alcohol withdrawal possible
CHLORDIAZEPOXIDE 20-40 mg qds
, reducing over 5d; if alcohol withdrawal; but benzodiazepines can make confusion worse; so, only Rx with benzodiazepine if sure
Note: larger doses are used in severe withdrawal-eg 40 mg qds, reducing over 10 days

IV NALOXONE 400 mcg,
if small pupils (?opiate OD)
IV FLUMAZENIL 200 mcg, over 15 secs, if ?benzodiazepine OD; then 100 mcg every 60 secs; max 1mg (2mg ITU)
Note: flumazenil is contraindicated in patients with epilepsy on longterm benzodiazepines; you may need to give further doses of naloxone and flumazenil (see BNF)

Procedures
: (see supportive measures below)

IV (+IV fluids, if dry)
OXYGEN, in hypoxic patient (this can quickly calm patient, and reduce confusion); if pulling mask off, try nasal cannulae
Warm up/cool down, as necessary

Supportive measures

Room: don't move about unecessarily, moderately lit side room preferable). Avoid excess noise, avoid over- or under-stimulation
Communication: clear. Avoid speciality jargon. Staff consistency (both doctors and nurses). Use health advocates (eg interpreters) where needed
Orientatation: reminders of the day, time, location and identification of surrounding persons; have a clock visible
Relaxation: eg watch television. Involve family and carers.
Familiarity: have familiar objects from home around patients especially glasses, walking aids and hearing aids. Maintain competence eg maintain walking in ambulant patient
Accidents prevention: nurse on floor if necessary (to prevent falls and fractures). Only use restraints if essential (patient may pull out essential line and exsanguinate)

Stop

Drug cause (especially hyponatraemia secondary to diuretics and/or SSRIs)
Alcohol
Any sedative drug (if in doubt, stop almost everything)

Treatment
(second line)

Drugs:
Have low threshold for broad spectrum IV antibiotics (± antivirals ± antimalarials):
IV BENZYLPENICILLIN 1.2 g qds + GENTAMICIN 5 mg/kg od;
before CT ± LP, if meningitis possible
± IV ACICLOVIR 10 mg/kg tds (infused over 60 mins) for 10-14 days, if encephalitis possibility (reduced dose in renal insufficiency)
± IV QUININE DIHYDROCHLORIDE: loading dose 20 mg/kg (maximum 1.4 g) over 4 hrs; then 8 hrs after loading dose, 10 mg/kg tds (also infused over 4 hrs); doses diluted in 250 mls N Saline, if cerebral malaria possible; watch for toxicity (QT prolongation)

Avoid sedation, unless absolutely necessary. But if extremely agitated/aggressive (ie danger to themselves or others) consider O/IM HALOPERIDOL 2-10 mg (start as low as possible, even 0.5 mg); maximum 18 mg/d; or PO QUETIAPINE 12.5-200 mg od. Start with 12.5mg od especially in elderly; and if more needed than 25 mg bd, please consult psychiatrist-on-call


Procedures
:
If unwell, urinary catheter, CVP, arterial line
Note: but may pull out any of these; so can make situation worse

Prescribing issues If drugs might be the cause (and no other diagnosis made), consider stopping all but essential ones - and inform GP when they go home. Polypharmacy is a problem in the elderly

Admit?

Usually
Note: but if frail elderly, consider alternative management plan, in community; ring GP, if you are doing this plan

Bed plan

Medical admission ward
± ITU

Referrals

Medical:
Depends on cause
± ITU

Other
:
SALT team etc, if CVA (pneumonia, 2o to aspiration?); does patient need NG feed? PEG?

The Rest


Maxim "Sedating a confused patient may make them worse"

Complications

• Hospital acquired infections, eg Clostridium difficile and MRSA
• Pressure sores
• Accidents: eg fractures (femoral or hip fractures from falls)
• Residual psychiatric and cognitive impairment
• Some progress to stupor, coma and eventual death
Note: patient may be a danger to you (aggression or HIV/Hep B/C positive, ie wear gloves)

Follow-up

Nil, usually
But consider HCE follow-up, if thought to be first presentation of dementia
Note that confusion may last longer than the underlying condition, sometimes for up to a year: [Ref] . This means that some patients will be discharged with persisting abnormalities. It is good idea to warn the family (and GP) about this issue. Quicker inpatient recovery is associated with a better outcome

Prognosis

Good, if confusion is mild. 5% in-hospital mort, 10% mort (25% functional decline) at 3 mths. 50% diagnosed dementia in 2y

2° Prevention
+ Health promotion

If alcohol or recreational drugs all/part of problem, refer to appropriate community services

Don't forget

• Encephalitis; DO NOT MISS THIS DIAGNOSIS; it's treatable
• SDH; so is this
• DRUGS DRUGS DRUGS (and look on back of card). If in doubt, stop almost everything. Ring GP, if necessary
• Find out whether this is acute, chronic (dementia), or acute-on-chronic confusion. Not doing this (ie making assumptions in Acute Confusion) is medicolegally dangerous
• Look at vital signs (including oximetry) and glucose
• Record mental test score (important baseline; like GCS in coma; note if fluctuating)
• CT head/LP if no obvious diagnosis, or no better at 24h
• Check for retention and constipation, in the elderly
• '3 treatable Ts' = Thyroid(hypo), TPHA + BTwelve deficiency

Red flags

• Pulling at lines, catheter etc
• Falling out of bed .. ie, may be danger to him/herself (protect them)

References


national guidelines UK/BGS: The prevention, diagnosis and management of delirium in older people: concise guidelines. Potter J et al. Clin Med; 6: 303�8, 2006 (pdf)

UK/Cornwall: Guidelines for the Diagnosis and Management of Acute Confusion (delirium) in the Elderly. Madeleine Purchas M, 2005 (pdf)

UK/RCP: The prevention, diagnosis and management of delirium in older people, 2006 (pdf)

Do guidelines improve the process and outcomes of care in delirium? Young LJ et al. Age and Ageing; 32: 525�528, 2003 (pdf)

UK/UKCPA: Detection, Prevention and Treatment of Delirium in Critically Ill Patients, 2006 (pdf)

review The Evaluation and Management of the Acutely Agitated Elderly Patient. Nassisi D et al. Mount Sinai J Med; 73: 976-984, 2006 (pdf)

Delirium: optimising management. Meagher DJ. BMJ; 322 (7279): 144�149, 2001

Clinical review. ABC of psychological medicine. Delirium. Brown TM et al. BMJ; 325: 644-647, 2002