OP-POISONING CLINICAL FEATURES AND MANAGEMENT.pptx

A BRIEF PRESENTATION ON ORGANOPHOSPHATE POISINING, CLINICAL FEATURES AND MANAGEMENT

1. OP-POISONING PRESENTATION ON

2. ORGANO-PHOSPHATES? Diverse group of chemicals used in domestic & industrial settings. Example(s) 1.Insecticides~Malathion,Parathion,diazinon,fanthio,dichlorvos,ethion. 2.Nerve gases~soman,sarin,tabun & VX. 3.Ophthalmic agents~echothiophate,isoflurophate . 4.Antihelmithes~trichorfon 3.tribufor,merphos. 4.Herbicides~tribufor,merphos. ^.Industrial chemicals~tricrosyl phosphate A POISON

3. INCIDENCE OF One of the Top cause of poisoning in the world Annual incidence of poisoning in agricultural countries 3-10% Poisoning?

4. PROPORTION OF DIFFERENT TYPES OF POISONING BMP Statistics

5. MECHANISM OF TOXICITY OF OP This leds to building-up of acetylcholinesterase in synaptic clefts & hyperexcitation of voluntary & involuntary muscles.

6. FATAL DOSE Malathion 1 g Parathion 125-175mg ora,80mg I/V or I/M. FATAL PERIOD fatal period 0.5-3 hours.

7. MUSCARINIC-LIKE EFFECTS PULMONARY Dyspnea,cough,cyanosis,froth at mouth & nose. GIT Nausea,vomiting,abdominal cramps,epigastric & substernal tightness,tenesmus,involuntary defecation. CVS Slight bradycardia Secretory Glands Excessive salivation,lacrimation & sweating EYE PINPOINT PUPILS,chromogenic tears(red tears){in some cases}. URINARY BLADDER Increase frequency of micturition & involuntary micturition

8. NICOTINIC-LIKE-EFFECTS Striated Muscle Muscle weakness,twitching,fasiculations,generalized weakness of muscles of respiration. CVS Tachycardia,hypertension

9. ACUTE CHOLINERGIC PHASE S/S Vomiting Diarhoea Pinpoint pupils Garlicky/kerosene-like- odour BBB;Bradycardia,ronchoconstriction & bronchorrhoea Muscular fasiculations Ataxia Coma In severe cases,flaccid paralysis leading to respiratory failure. Starts within few minutes of exposure. lasts for 48-72 hour .

10. MANAGEMENT ECG O2 SATURATION BLOOD GASES SERUM ELECTROLYTES SERUM AMYLASE SERUM GLUCOSE INVESTIGATIONS

11. TREATMENT Maintain A,B & C. High-flow oxygen. Maintain an IV- acess . External decontamination. Gastric Lavage. Atropine,2-5mg IV/IM/IO bolus in adults,double the dose every 3-5 minutes until signs 0f atropinization i.e wheezing and bronchial secretions stop. TACHYCARDIA & MYDRIASIS ARE NOT CONTRAINDICATIONS TO ATROPINE USE. HUNDREDS OF MILLIGRAM MAYBE NEEDED OVER SEVEREAL DAYS IN SEVERE POISONING. (In children the dose is 0.015-0.05mg/kg/15mins) Inhaled Ipratropium 0.5mg with parenteral atropine maybe helpful for bronchospasm,may repeat.

12. Cholinestrase reactivation:Pralidoxime,adult dose 1-2g(1 amp=200 mg) IV (slowly over 30 min),in children 25-50 mg/kg. Diazepam(if convulsions are present(10mg dose IV,may repeat if seizures occur)

13. ATROPINE SHOULD BE TAPERED OFF JUDICIOUSLY ,OTHERWISE IT MIGHT LED TO RESPIRATORY FAILURE OR PULMONARY EDEMA WHEN , HR >80 bpm Skin is dry BP is adequate.

14. INCIDENCE:20% Occurs 1-4 days after the episode of original poisoning & may last for 3-4 weeks. P/ C:Muscular weakness that starts from ocular muscles to head & neck to proximal limbs to finally Muscles of respiration. TREATMENT:Physiotherapy . INTERMEDIATE SYNDROME

15. OP-INDUCED DELAYED POLYNEUROPATHY A rare complication. occurs 2-3 weeks after acute exposure. Pathogenesis;affects enzymes other than AChE,thereby it particularly affects the long myelinated neurons. Clinical features: muscle cramps,numbness,paresthesia,flaccid paralysis of lower & upper limbs,sensory loss is variable.

16. Physiotherapy. TREATMENT

17. Thankyou.

18. Davidson’s Principles of Medical Sciences,24 th Edition. Medscape Article on OP-POISONING. UpToDate. RESOURCES