1. Dr. Mushtaq Talib

2.  Comprises psychiatric disorders that arise from demonstrable abnormalities of brain structure and function.  Cognitive impairments are the most prominent feature, especially in dementia and delirium.  But, behavioral and emotional disturbances are also common, and may be the sole manifestations.

3.  Delirium  Dementia  Amnestic ( or amnesic) syndromes  Epilepsy  Head injury  Other neuro-psychiatric disorders( focal cerebral syndromes, infections, tumors, and multiple sclerosis)  Secondary or symptomatic neuro-psychiatric disorders ( due to other disease in the body)

4.  Amnesia is loss of memory, and amnestic syndromes (disorders) are those in which memory is specifically and persistently affected.  Amnestic disorder( by DSM IV) is defined as a specific impairment of episodic memory, manifesting as inability to learn new information( anterograde amnesia) and to recall past events( retrograde amnesia) accompanied by significant impairment in social or occupational functioning and with evidence of a general medical condition” etiologically related to memory impairment”.

5.  Transient: 1. Transient global amnesia 2. Transient epileptic amnesia 3. Head injury 4. Alcoholic blackouts 5. Post-electroconvulsive therapy 6. Posttraumatic stress disorder (PTSD) 7. Psychogenic fugue

6.  Permanent: 1. Korsakov (Korsakoff) syndrome 2. Encephalitis 3. Posterior cerebral artery and thalamic strokes 4. Head injury

7.  The cardinal feature is profound deficit of episodic memory  Disorientation for time,  loss of autobiographical information  Severe anterograde amnesia for verbal and visual material  Lack of insight to the amnesia  Confabulation: gaps in memory are filled by a vivid and detailed wholly fictitious account of recent activities which the patient believes to be true.

8.  Lesions in the medial thalamus, other midline diencephalic structures, or medial temporal lobes.  Korsakov syndrome: which usually follows an acute neurological syndrome called Wernicke’s encephalopathy. This is caused by thiamin deficiency,secondary to alcohol abuse, although it occasionally results from hyperemesis gravidarum and severe malnutrition.

9.  Inquire about alcohol abuse  Reduced red cell transketolase level ( marker of thiamin deficiency)  Brain MRI: increased MRI signal in midline structures

10.  Korsakov syndrome should be assumed to be the cause of amnestic syndrome until another etiology is demonstrated  Urgent treatment with thiamin should be started without waiting the results of investigations (parenteral thiamine)  Rehydration  General nutritional support  Treatment of alcohol withdrawal  Rehabilitation and support

11.  Sudden onset of isolated anterograde amnesia in a clear sensorium generally lasting for less than 24 hours  Due to dysfunction of the circuits mediating episodic memory  Needs to be considered in the differential diagnosis of paroxysmal neurological and psychiatric conditions that occur in middle and late life.

12.  Characterized by global impairment of consciousness ( clouding of consciousness),resulting in reduced levels of alertness, attention, and perception of the environment.  It occurs in 15-30% of patients in general medical or surgical wards.  Other terms: acute confusional state, acute organic syndrome, acute brain failure

13.  The cardinal feature is disturbed consciousness  Manifested as drowsiness, decreased awareness of surroundings  Disorientation in time and place, and distractibility  In most severe cases ;patient may be unresponsive( stuporose)  May start as mental slowness, distractibility, perceptual anomalies, and disorganization of the sleep-wake cycle.

14.  Symptoms vary at different times of the day and between different patients  Symptoms are worse at night  Some patients are hyperactive,restless, irritable and have psychotic symptoms  Some are hypoactive with psychomotor retardation and perseveration.  Repetitive,purposeless movements are common in both forms  Thinking is slow

15.  Ideas of reference and delusions are common but usually transient  Illusions, misinterpretations and visual hallucinations sometimes with fantastic contents  Anxiety,depression, and emotional lability are common  Patients may appear frightened and perplexed  Attention and registration are often impaired and on recovery there is usually amnesia for the period of the delirium.

16.  Old age, frailty, and prior medical and neurological disorders lower the threshold for developing delirium.  The patho-physiological basis of delirium is unclear.  The neurotransmitters dopamine and acetylcholine are implicated.

17.  Drugs : alcohol intoxication, withdrawal, opiates, drugs with anticholinergic properties, any sedative, digoxin, diuretics, lithium, and steroids.  Medical conditions: febrile illness, septicaemia, organ failure( cardiac, renal, hepatic), hypo or hyperglycaemia, post-operative hypoxia, thiamine deficiency  Neurological conditions: epileptic seizure, head injury, space occupying lesion, encephalitis,cerebral hemorrhage.  Others : constipation, dehydration, pain, sensory deprivation.

18.  Delirium is a medical emergency  It is very essential to identify and treat the cause  Drugs (side effect or withdrawal) should be suspected until there is evidence of another cause.  While doing investigations, measures should be taken to decrease distress and control agitation  These include: frequent explanation, reorientation, and reassurance.  Nursing : minimal number of nurses, quite room, good lightening, relatives should be encouraged to visit regularly.

19.  Medications to control agitation and distress and permit adequate sleep  Drug of choice is usually an antipsychotic  Haloperidol is conventionally used (2-10 mg/day)  Antipsychotics should be avoided in alcohol withdrawal and epilepsy because of the risk of seizure.  All sedative drugs should be used sparingly in liver failure because of the danger of precipitating hepatic coma.