Roshan Gunathilake MD

John Hunter Hospital Newcastle, Australia

DELIRIUM IN THE WARD

Case scenario

You are the evening RMO. You have been asked to see a 84-year-

old man on D2 post-elective R/TKR. Nurses state that he is confused since

1800, spitting out his medications, yelling at the staff, and wandering in the ward.

Background

84-year-old man Lives with wife in a retirement village Independent in ADLs Admitted for elective R/ TKR

Background

Previous R/ PACI (2010) Mild cognitive impairment Hearing impairment Stable CAD Hypertension T2DM (metformin) OA Alcohol 1-2 Units/day

Medications

Aspirin Metoprolol Perindopril + indapamide Atorvastatin Meformin Vitamin D Temazepam Prophylactic SC heparin Regular paracetamol, PRN Oxycodone

Physical Examination

Agitated but cooperative Confused Disoriented Vitals P 104, BP 110/72, RR18, spO2 98 RA Chest clear Abdomen SNT No focal neurology, pupils normal Clean surgical wound No DVT

Questions

What is the likely diagnosis? What might be the cause? What are his risk factors? What investigations will you request? How will you manage him? What is his prognosis?

Delirium

Derived from Latin term meaning “off track”

Not a disease, but a syndrome with multiple causes that result in a similar constellation of symptoms

An acute syndrome characterized by altered attention, cognition and consciousness

May be the only sign of a serious medical illness in an older person

Clinical hall marks

1. Acute onset + Waxing and waning symptoms

2. ↓ Attention span3. Disorganized thinking4. Altered LOC

Incidence/ prevalence

Very common but is often not detected or misdiagnosed

Prevalence and incidence varies across patient populations and health care settingso Prevalent delirium 10 - 24% o Incident delirium up to 56%

among older hospitalized patients

Risk factors for delirium

advanced age dementia Hx of delirium neurological

damage functional

disability visual and hearing

impairment

polypharmacy psychoactive

drugs alcoholism multiple / severe

chronic medical conditions

dehydration depression

Precipitating factors

Metabolic – hypoxaemia, hypoglycaemia, electrolyte & acid-base derangements

Infective – urinary tract infection, pneumonia, CNS infection

Structural – Cerebrovascular event, urinary retention

Toxic – drugs (incl. withdrawal) or poisons Environmental – being in hospital or ICU,

physical restraints, bladder catheter, multiple procedures, surgery, pain

Medications known to cause delirium

Anticholinergics Antihistamines Narcotics Benzodiazepines Antiparkinson agents Digoxin Lithium Steriods

Risk factors & precipitating factors

Moderate to high risk

Very High Risk

Low risk Moderate to high risk

Low High

High

Vulnerability

Level of insult

Inouye SK, Charpentier PA, Precipitating factors for delirium in hospitalized elderly persons. Predictive model and interrelationship with baseline vulnerability. JAMA 1996; 275(11): 852-7

Clinical features

Fluctuation of symptoms Clouding of consciousness Cognitive deficits (disorientation,

inattention) Psychomotor abnormalities:

floridly agitated, hyperactive drowsy, hypoalert, quiet (Hypoactive delirium)

Sleep–wake cycle disturbance Perceptual & thought disturbances (e.g.

misinterpretations, illusions, hallucinations)

Diagnosis

Clinical features Collateral history Medication review Focused physical exam CAMI

Several instruments for evaluating delirium are available.

The Confusion Assessment Method (CAM) is used widely

It has reported sensitivity > 94% and specificity > 90%

Further Investigation

FBC EUC, Ca++, LFTs Random BSL ECG, cardiac enzymes CXR Urinalysis Brain imaging, CSF Drug levels

Differential diagnosis

Dementia Depression Psychotic illness Sun downing

FEATURE DELIRIUM DEMENTIA

ONSET Acute GradualDURATION Hours – weeks Months – years

COURSE Fluctuating Progressive deterioration

CONSCIOUSNESS Impaired NormalPERCEPTUAL

DISTURBANCECommon Occurs in late

stagesSLEEP-WAKE CYCLE Disrupted Usually normal PROGNOSIS Potentially

reversible Not reversible

PRIMARILY AFFECTS Attention Memory MEDICAL EMERGENCY? Yes No

Management of delirium

Delirium is best managed by clinicians with expertise in delirium management, and in most cases should involve a multidisciplinary team.

Components of delirium Mx

1. Identify the cause where possible2. Correct the cause / precipitating

factors3. Manage the symptoms of delirium4. Provide a supportive care environment5. Prevent complications6. Educate the patient and their carers

Non-pharmacological management: Environmental Calm, comfortable environment Lighting appropriate to time of day Orientation cues – clock, calendar Familiar objects or photographs from home Encourage family and carer involvement Remove hazards : low bed, secure facility Avoid restraints (aggravate delirium,

increase injuries ) Avoid room changes

Non-pharmacological management: Nursing care-based Use of staff with training in delirium care One-on-one nursing where relevant Same staff members to care for the

patient during and across shifts Minimize sensory deprivation Validation and reality orientation

strategies Providing relaxation strategies to assist

with sleep.

Multicomponent Mx of delirium symptoms

Pharmacological interventions

Cease/ ↓ drugs that cause delirium Manage discomfort or pain Regulation of bowel function Drug therapy is reserved for patients

who are at risk of harming self /others

Pharmacological interventions Understudied area, with only a

limited number of small trials; Very few data comparing different drugs

Even drugs that are used to treat delirium, particularly if given in excess, can prolong or worsen delirium.

Pharmacological interventions: antipsychotics

Antipsychotics are generally the 1st line (except in delirium tremens)

Start low and go slow (e.g. haloperidol 0.5 mg, risperidone 0.5 mg or olanzapine 2.5 mg)

Titrate dose, review periodically, monitor for oversedation

No clear evidence that atypical antipsychotics are more effective > typical

But have fewer extrapyramidal side effects

Pharmacological interventions: benzodiazepines

Benzodiazepines are the treatment of choice for delirium tremens & delirium associated with benzo- withdrawal

Geriatric patient populations are at greater risk of developing complications from benzo- use

Long acting benzo-s, in particular, have been shown to increase the risk of delirium.

Prognosis

Delirium is associated with ↑adverse outcomes:

o Mortalityo Hospital mortality 25 - 33%o independent marker for mortality <

12 months after discharge (HR 2.11) o length of stay (x2)o Complications : falls, bed sores,

incontinence o Cognitive and functional declineo Nursing home admission

Course

Delirium may be very persistent. Unresolved delirium:

60% after 1 week 20% after 2 weeks 15% after 4 weeks 5% persists >4 weeks

Inattention, memory impairment and disorientation may be still present at up to 12 months.

Prevention strategies

Reorient and mobilise the patient Reduce sensory deprivation Ensure the patient is hydrated Implement a non-pharmacologic sleep

regimen Limit catheters and restraints

Summary

Delirium is a common medical emergency, with ↑morbidity and mortality rates, affecting elderly.

Risk for delirium should be assessed in all older persons admitted to a health care setting.

Timely diagnosis, multicomponent intervention and judicious use of medications can improve outcomes.

Antipsychotics are reserved for patients with severe behavioral and psychological symptoms.

References

1. Caplan G. Managing delirium in older patients. Aust Prescr 2011;34:16–18)

2. Inouye AK. Delirium in older persons. NEJM 2006;354: 1157-65

3. Australian Society for Geriatric Medicine; Position Statement No.13 : Delirium in Older People (2005)

4. Delirium Clinical Guidelines Expert Working Group. Clinical Practice Guidelines for the Management of Delirium in Older People. (AHMAC 2006)

5. Inouye SK, Charpentier PA, Precipitating factors for delirium in hospitalized elderly persons. Predictive model and interrelationship with baseline vulnerability. JAMA 1996; 275(11): 852-7