Coagulants

coagulants in detail with all drugs, mechanism of action, advantages, adverse effect, contraindication with example and pictures.
in simplified manner , easy to understand

1. Coagulants by: bibi umeza

2. Drugs affecting coagulation Haemostasis & blood coagulation involve complex interactions between the injured vessel wall, platelets & coagulation factors For blood to clot, a cascading series of proteolytic reactions is started by. 1. Contact activation of Hageman factor: intrinsic system. Slow and takes several minutes to activate factor X.

3. 2. Tissue thromboplastin - extrinsic system. Needs a tissue factor. Activates factor x in seconds. Clotting factors are present in the plasma in the inactive form. ↓partial proteolysis. Active protease ----→ activates next factor. Antithrombin , protein C, protein S, antithromboplastin and the fibrinolysin system ----  oppose coagulation & lyse formed clot

4. The coagulation cascade

5. Coagulants These are agents which promote coagulation and are indicated in the haemorrhagic states. Fresh whole blood/plasma provide all the factors needed for coagulation.

6. Classification of coagulants

7. Systemic agents Vitamin K: K 1 [ from plants]- phytonadione . K 2 [ from bacteria]- Menaquinones K 3 [ synthetic] Fat soluble- Menadione , - Acetomenaphthone Water soluble- Menadione sod.bisulfite - Menadione sod.diphosphate

8. Vitamin K Fat soluble, required for the synthesis of clotting factors. Daily requirements: it is uncertain, variable amount becomes available from colonic bacteria. 50-100 μ g/day Dietary sources: green leafy vegetables. Liver, cheese etc.

9. Action: acts as a cofactor at a late stage in liver during synthesis of coagulation proteins- II, VII, IX & X.

10. Utilization: Fat soluble forms are absorbed from intestine via lymph and require bile salts for absorption. Stored mainly in liver. Metabolites are excreted in bile or urine.

11. Deficiency: liver disease, obstructive jaundice malabsorption , long term antimicrobial therapy

12. Use Dietary deficiency >5-10mg/day oral/ parenteral vit K Prolonged antimicrobial therapy Obstructive jaundice/ malabsorption syndromes > vit K 10mg/day i.m ./orally Liver disease(cirrhosis, viral hepatitis) Newborns> vit K 1mg i.m . Overdose of oral anticoagulants:K 1 .dose depends on the severity of bleeding & hypoprothrombinaemia Prolonged high dose salicylate therapy.

13. Toxicity Flushing, breathlessness, constriction in chest, fall in BP. Sweating Cyanosis, etc.

14. miscellaneous Fibrinogen - control bleeding in haemophilia , Antihaemophilic globulin (AHG) deficiency & acute fibrinogenemic states

15. Antihaemophilic factor : concentrated human AHG prepared from pooled human plasma. Used to control bleeding in haemophiliacs ADVERSE EFFECTS: fever with chills, headache and skin rashes.

16. Ethamsylate : It decreases capillary bleeding when platelets are adequate; probably exerts antihyaluronidase action & improves capillary wall stability, but does not stabilize fibrin. It is used in capillary bleeding in menorrhagia , after abortion, PPH, epistaxis , haematuria , malena,after tooth extraction. SE:nausea,rash,headache,fall in BP

17. Desmopressin : Releases factor VIII & von Willebrand’s factor from vascular endothelium. Used to control bleeding in haemophilia and von willebrands’s disease

18. Adrenochrome monosemicarbazone : Reduce capillary fragility,control oozing from raw surfaces & prevent microvessel bleeding. e.g. epitaxis , haematuria,etc .

19. Rutin : Plant glycoside. reduce capillary bleeding Used along with vit C

20. Local haemostatics (styptics) These are substances used to stop bleeding from a local & approachable site. Effective on oozing surfaces . E.g. bleeding following tooth extraction, abrasion, epistaxis , etc.

21. Thrombin- obtained from bovine plasma. It is applied as dry powder on the bleeding surface. Used in haemophilia, neurosurgery, skin grafting.

22. 2. Fibrin-obtained from human plasma and is dried; it is used as sheets or foam for covering or packing bleeding surfaces. It is left in situ.

23. 3. Gelatin foam- spongy gelatin. Moistened with saline or thrombin solution & used for packing wounds. Absorbed in 1-2 months. It is left inside.

24. 4. Russels viper venom- applied locally. Acts as thromboplastin . Used to stop external bleeding in haemophiliacs 5. Vasoconstrictors .-0.1% solution adrenaline To stop epistaxis . 6. Astringent- tannic acid or metallic salts. Bleeding gums,bleeding piles.

25. Thank you