Organic Mental Disorders

1. Organic Mental Disorders

2. Overview of Psychiatric Disorders • Those due to known organic cause • Those in which organic factor has not yet been found • Those that are primarily due to psychosocial factor

3. Contd… • Organic mental disorders are behavioral or psychological disorders associated with transient or permanent brain dysfunction due to cerebral disease either by primary brain pathology or secondary due to systemic disease • Organic mental disorder should be first considered in evaluating patient with any psychological or behavioral clinical syndrome

4. High Index of Organic Mental Disorder • 1st episode • Sudden onset • Older age of onset • H/O drug or alcohol use disorder • Concurrent medical or neurological illness • Neurological symptoms- seizure, impaired consciousness, head injury,confusion,disorientation, memory impairement • Prominent hallucinations

5. Subcatogery of OMD • Delirium • Dementia • Organic amnestic syndrome • Other OMD

6. Delirium • Delirium is a transient, potentially reversible dysfunction in cerebral metabolism, that has an acute or subacute onset and is typically manifested by alterations of levels of consciousness and change in cognition. • It is the most common psychiatric syndrome found in a general medical hospital. • Elderly patients presenting to the emergency room is as high as 80%

7. Delirium by Other Names • Intensive care unit psychosis • Acute confusional state • Acute brain failure • Encephalitis • Encephalopathy • Toxic metabolic state • Central nervous system toxicity • Paraneoplastic limbic encephalitis • Sundowning • Cerebral insufficiency • Organic brain syndrome

8. Causative factors for delirium • Central nervous system disorder • Metabolic disorder • Systemic illness • Medications • Seizure MigraineHead trauma, brain tumor, subarachnoid hemorrhage, subdural, epidural hematoma, abscess, intracerebral hemorrhage, cerebellar hemorrhage, nonhemorrhagic stroke, transient ischemia • Electrolyte abnormalitiesDiabetes, hypoglycemia, hyperglycemia, or insulin resistance • Infection TraumaChange in fluid statusNutritional deficiencyBurnsUncontrolled painHeat strokeHigh altitude (usually >5,000 m) • Pain medications, anti-HTN,anticonvulsantsAntibiotics, antivirals, and antifungalsSteroids,sedatives,alcoholAnesthesia

9. Contd… • Cardiac • Pulmonary • Endocrine • Hematological • Renal • Hepatic • Neoplasm • Drugs of abuse • Toxins • Cardiac failure, arrhythmia, myocardial infarction, cardiac surgery • Chronic obstructive pulmonary disease, hypoxia, acid base disturbance • thyroid abnormality, parathyroid abnormality, Adrenal crisis • Anemia, leukemia, blood dyscrasia, • Renal failure, uremia • Hepatitis, cirrhosis, hepatic failure • Neoplasm (primary brain, metastases, paraneoplastic syndrome) • Intoxication and withdrawal • Heavy metals and aluminum

10. Predisposing Factors • Pre-existing brain damage or dementia • Extremes of age • H/O delirium • Alcohol or drug dependence • Generalized or focal cerebral lesion • Chronic medical illness • Pre-and post-op • Severe psychological symptoms • Rx with psychotropic drugs • H/O head injury • Vision impairment • Use of bladder catheter • Malnutrition • Epidural use

11. The diagnostic features of delirium in the current DSM (DSM-IV) • Disturbance of consciousness • Change in cognition • The disturbance that develops over a short period of time (usually hours to days) and tends to fluctuate during the course of the day. • Evidence from the history,.

12. According to the ICD-10for a definitive diagnosis of delirium symptoms mild or severe,should be present in each one of the following areas:- 1)Impairement of consciousness and attention. 2)Global disturbances of cognition. 3)Psychomotor disturbances. 4)Disturbances of sleep-wake cycle 5)Emotional disturbances, Eg.depression,anxiety,fear,irritability.

13. Delirium due to a general medical condition 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. • Substance intoxication delirium There is evidence from the history, physical examination, or laboratory findings of either 1 or 2: 1 the symptoms developed during substance intoxication 2 medication use is etiologically related to the disturbance. • Substance withdrawal delirium There is evidence from the history, physical examination, or laboratory findings that the symptoms developed during, or shortly after, a withdrawal syndrome. • Delirium due to multiple etiologies There is evidence from the history, physical examination, or laboratory findings that the delirium has more than one etiology • Delirium not otherwise specified

14. Diagnostic features • Discriminating features 1 Waxing and waning awareness. 2 Acute onset of cognitive dysfunction. • Consistent features 1 Disorientation, usually to time. 2 Memory impairment, particularly recent memory. 3 Hallucinations, typically visual, and misperceptions. 4 Language dysfunction, such as an impaired ability to name objects. 5 Definable cause. • Variable features 1 Hyperactivity and/or hypoactivity. 2 Mood disturbance. 3 Alteration in sleep-wake cycle. 4 Delusions. 5 Impaired judgment. 6 Dreamlike experience for patient.

15. 7)diurnal variation is marked,usually worsening of symptoms in evening and night(called sundowning). • 8)speech and thought disturbances like slurring of speech,incoherence,dysarthria. • 9)motor symptoms include asterixis(flapping tremor).

16. Laboratory Workup of the Patient with Delirium • Standard studies   Blood chemistries (including electrolytes, renal and hepatic indexes, and glucose)   CBC   TFT   Serologic tests for syphilis   HIV antibody test   Urinalysis   Electrocardiogram   Electroencephalogram   Chest radiograph   Blood and urine drug screens • Additional tests when indicated   Blood, urine, and cerebrospinal fluid (CSF) cultures   B12, folic acid concentrations   CT & MRI   LP and CSF examination

17. Differential Diagnosis

18. Treatment • The treatment of delirium involves treating the primary causative condition, providing supportive care, and preventing injurious behaviors.e.g. o2 for hypoxia, 100mg of B1 for thiamine deficiency • Emergency psychiatric Rx e.g. benzodiazepines (10mg of diazepam or 2mg of lorazepam IV) or antipsychotics (5mg of haloperidol or 50mg of chlorpromazine IM) • Supportive medical and nursing care • If severe pain or dynpnoea, prescribe opioids for both their analgesic and sedative effects

19. Prognosis • Among delirious hospitalized medical patients mortality is as high as 20–40%.

20. Prevention • Good general medical and nursing care • Recognition and effective treatment • Screening for alcohol dependence is important • Elderly patients unwell physically or having a major procedure, who have pre-existing cognitive problems. • Hypnotics are associated with an increased risk of delirium; routine use should be avoided