Acute Organic Reactions

Acute Confusional StateAcute Brain Syndrome

Prototype e.g. Delirium

Organic disorders-features

Diseases that affect the brain▪ 10 Disease of the brain▪ Systemic conditions that 20 affect the brain

Disrupts normal brain function through biochemical, electrical or mechanical disturbances

Delirium is the extreme form of organic reaction from dulling to Coma ( Glasgow Coma scale)

Delirium is a transient, organic mental syndrome of acute onset, characterized by disturbances in cognition, attention, perception, thinking, consciousness, psycho motor activity and sleep wake cycle.

Acute Organic Reaction -features

Aetiologically diverse but with similar syndrome

(manifestation): common final pathway Common at the extremes of age Commonly seen in general hospital settings or in

geriatric wards Occurs at rates ranging from 10% to 30% of all

hospital admissions (usually unrecognized) Usually acute in onset, fluctuating in nature and

lasts for few hours, days to weeks Reversible when cause treated It carries a high mortality rate (up to 25% ) when

untreated

Aetiology

Systemic conditions- 20 affects brain function Drug intoxication

▪ Anticholinergics, Psychotropics, Anticonvulsants, Antiparkinsonian, antiarrythmics, Steroids, Salicylate, Lithium, Alcohol, Cannabis, Ecstasy, …

Drug withdrawal▪ Alcohol, Benzodiazepines

Infections/ inflammations▪ Chest infections, UTI, Systemic infections- Typhoid, cerebral malaria,

Septicaemia, rheumatic chorea, influenza, streptococcal infection ▪ Meningitis, Encephalitis, HIV, Neurosyphilis, (10 affects brain)

Hypoxia ▪ Respiratory disease- bronchoneumonia, Heart disease (cardiac dysrhythmias,

CCF, silent coronary infarction), CO poisoning, Post anaesthesia, silent GI bleeding,

Metabolic causes ▪ Uraemia, Hepatic encephalopathy, Electrolyte imbalance, hypoglycaemia,

ketoacidosis, alkalosis, hypercapnia Endocrine

▪ Thyroid (hyperthyroid crisis, myxoedema madness), Adrenal, Pituitary problems, Addisonian crisis, Diabetic pre-coma

Aetiology ctd..

Nutritional ▪ Vitamin deficiencies (B12, Thiamine (Wernicke’s

encephalopathy), Pellagra, Folic acid..) Other rare causes

▪ Heavy metal poisoning▪ Non-metastatic effect of CA▪ SLE▪ Porphyria

Primary CNS conditions▪ Head injury- EDH, SDH▪ Cerebro vascular causes – CVA, TIA, SAH, hypertensive

enchephalopathy▪ Epilepsy- CPS, Post ictal confusion, petit mal status ▪ SOL

Clinical features

Impairment of consciousness▪ Dulling of awareness to …….coma

▪ Fluctuations, lucid intervals

▪ Diurnal variation

Disorientation▪ Time, place, person

Disturbances in attention and concentration▪ Difficulty in focusing and keeping attention

Memory impairment

▪ Amnesic gaps

Perceptual disorders

▪ Illusions

▪ Hallucinations –visual, tactile, auditory …..

Clinical features ctd.. Disorders of thinking

▪ Incoherence, fragmentation

▪ Stereotype thinking, preservation, impaired grasp

▪ Mental fatigue , defective reality testing, incomprehension

▪ Delusions – persecutory, occupational (delirium), others

Emotions

▪ Apathy and withdrawn

▪ Fear, anxiety, panic, terror..

▪ Depression

▪ Labile emotions

Psychomotor

▪ Hyper - hypo alertness (agitation or retardation) or mixed

▪ Diurnal fluctuation

Disturbance in sleep wake cycle

▪ Reversal

▪ Disturbing dreams and nightmares

Differential diagnosis

Chronic confusional state – Dementia

Acute on chronic

Psychotic illness

Dissociative illness

Investigations

Routine investigations▪ FBC, BP, BU, SE, FBS, LFT, Culture, ECG, CXR

….

Specific investigations▪ Drug levels, vitamins levels▪ TFT, Other endocrine levels▪ LP, Skull X ray▪ EEG▪ CT, MRI, PET…

Management - General

Find out the aetiology and treat it

General measures▪ Nutrition, fluid, electrolytes, other general health

measures

Nursing ▪ Quite, well lighted area▪ Simple environment with familiar objects – not having

any harmful objects▪ Keep under close observation▪ Risk assessment▪ Avoid changing staff▪ Clear instructions, adequate explanations, repeated

orientation▪ Be supportive

Vitamin B, Broad spectrum Antibiotics ?

Management - Pharmacological

Some general principles when prescribing medication use one drug at a time; Look for side-effects of prescribed medications keep the use of sedatives and antipsychotics to a

minimum; tailor dose according to age, body size and degree of

agitation; titrate dose to effect; increase scheduled doses if regular ‘as needed’ doses

are required all medication should be reviewed at least every 24

hours.

Agitation, Psychotic features & Sleep problems▪ Typical Antipsychotics – Haloperidol▪ Atypical antipsychotis – Risperidone, Olanzapine▪ Beware of QTc interval – ECG monitoring▪ Benzodiazepines – Lorezepam▪ Others

THANK YOU

References

Lishman’s Organic Psychiatry, 4th Edition, Wiley-Blackwell, 2009

Brain images from http://health.howstuffworks.com/human-body/systems/nervous-system/brain-pictures4.htm