 Hello everyone, welcome back to another session in dentistry and more today. We have hemostatic agents in oral surgery so normally blade circulation through intact Masculature happening without any trombus formation. Okay, so this hemostasis is the state of fluid equilibrium in the vessel so hemostatic agents are The products or materials we apply to cause the bleeding to stop so there are various mechanisms by which the bleeding can be stopped so the Methods what we can apply are classified as mechanical methods thermal or energy based methods then chemical methods and also we have Topical agents Topical hemostatic agents which can be again classified as passive and active agents passive Active agents So let's learn the process of hemostasis and hemostatic agents So the natural process of hemostasis or coagulation we already learned There are mechanisms such as intrinsic pathway extrinsic pathway all this Intrinsic and extrinsic pathway and the coagulation cascade How the fibrant load is formed with the help of various coagulation factor? So we know everything coagulation factors Factor number 1 to 13. So this we learned in physiology textbook So there are natural inhibitors of coagulation cascade which is protein C protein S tissue factor pathway inhibitor Antithrombin or thrombomodulin these are the natural inhibitors of coagulation cascade So why to use hemostatic agents? It is mainly to minimize the blood loss and improve visualization It also saves operative time so It reduces the post operative drainage and infection and it decreases hospital length of stay So what are the characteristics of hemostatic agents? So first thing is its capability to stop large vessel arterial and venous bleeding within minutes of application and There should not be any requirement for mixing or pre application preparation And it should be simple to apply It should be lightweight and durable It should have long shelf life in extreme environment And it should be safe to use with no risk of injury to tissues or Transmission of infection and it should also be cost effective So we have various mechanisms Mechanical methods thermal or energy based methods chemical methods topical hemostatic agents which can be passive and active agents and Some other methods are also there. So we'll start with the mechanical methods. So mechanical methods. We have Direct pressure mechanism that is direct pressure Then in mechanical we have fabric parts and sponges fabric Sponges Goses Then we have sutures staples or ligating clips So these comes under mechanical methods So the direct pressure direct pressure is the simplest and fastest method So it is a surgeon's first choice because arterial bleeding Can better be controlled than the venous bleeding. So that is a direct pressure method. Then we have fabric pads Goses and sponges so application of direct pressure concept Packaging of this body cavity or the surgical area and a number of sponges used during surgery Needs to be counted and these are like temporary measures Then sutures staples and ligating clips So sutures and ties used as a ligature to tie off the blood vessels chances of tissue reaction And injury and allergic reactions are there For staples, we need to have stapling device. Nowadays staples are gaining much popularity Efficient method it is when we have a moving tissue Then ligature clips are quick and easy to apply We need to have a applicator and Site of application should be very clearly visible for to apply this So now let's move to the thermal methods So in thermal or energy based methods our first one we have electro surgery electro surgery Then we have Ultrasonic devices, then we have Laces So electro surgery The use of high-frequency Alternative current for cutting coagulating or Wepracing tissues, but there are potential risks for this because it can cause injury Patient injury user injury and there will be chances of fires and electromagnetic interference So there are two methods one is monopolar and bipolar bipolar So the monopolar is the most frequently used bipolar is better on delicate tissues or small anatomic structures So bipolar vessels ceiling device which applies heat with high compression And which is capable of simultaneously sealing and transfecting vessels up to 7 Millimeter in diameter So large tissues can be managed using bipolar devices The second one is ultrasonic devices which converts electrical energy to mechanical energy Okay electrical energy to mechanical energy Which simultaneously cuts and coagulates the tissues and it needs less Thermal power, so it is less damaged to the tissues compared to electro surgery and the last one is lasers So laser energy delivered to the target sites And it can be reflected scattered transmitted or absorbed. So this is a very newer technique Used for haemostasis. So this all comes under thermal or energy based electro surgery Ultrasonic devices and lasers. Now, let's move on to the chemical methods In chemical methods, we have the most common epinephrine or adrenaline epinephrine is Vasoconstrictor then we have the vitamin K Vitamin K is involved in That coagulation, you all know Then we have Potamine Then we have Desmopressin It's a very commonly asked question the hemostatic agents The last one we have lysine Analogues So the epinephrine epinephrine is the most commonly used which causes direct vasoconstriction and Increases the heart rate. Okay, so the problem is with it is not good for heart patients or patients with heart problems Because it increases the systolic and diastolic pressure. So it can be applied topically or Interacted with Local anesthesia. So most of the local anesthetic agents has epinephrine in one is to 80,000 Next we have the vitamin K So it is administered Pre-operatively to reverse the effect of warfarin and to avoid need of transfusion of FFP to avoid the need of transfusion of FFP That is nothing but fresh frozen plasma. Next we have protamine Protamine is the only agent with ability to reverse Heparin anticoagulation. Okay, so this is a parent and warfare in our anticoagulants So this proton can reverse the haparin anticoagulation effect Which can cause an afl axis Acute pulmonary vasoconstriction and right ventricular failure. So it should be used cautiously Next we have desmopressin. So it stimulates the release of one will brand factor and enhances the primary Hemostatic mechanism Then lastly, we have lysine analogues So they are amino caproic acid Amino caproic acid then Tran Semic acid Semic acid Then they are anti-fibrolytic agents and competitively inhibit the activation of Plasminogen, okay Plasminogen So they inhibit activation of Plasminogen and They are variable in effect That is the lysine analogues. So these are the Chemical methods epinephrine, vitamin K, Protamine, desmopressin and lysine analogues. Now, let's see what are the topical agents? Topical agents we have both passive and active products So Topical agents which provides a physical lattice like matrix that adheres to bleeding site Okay, there will be a matrix So this matrix activates the extrinsic Cloting pathway Extrinsic coating pathway then platelet aggregates and form a clot so that is a concept this Method that is a passive Topical agents which provides a lattice Matrix Then this matrix activates extrinsic pathway, then there will be platelets and Clote formation So this passive agents which rely on fibrin production and hence can be used only in a patient with Intact coagulation cascade. So there should be no problem with the normal Hey more static mechanism So passive agents can absorb several times its weight in fluid Still this expansion of the agent can cause complications like compression of the surrounding tissues So we have the first one collagen based products collagen based products so Activated these products are activated on contact with pleading and it provide Stable matrix for clot formation which enhances the platelet aggregation degranulation and release of cloting factors So which is basically derived from either bovine tendon or bovine dermal collagen? bovine tendon or bovine dermal collagen normal Collagen so this is derived from one of these one of these materials that is bovine tendon or bovine dermal collagen So the product is micro Fibrillar collagen Hemostat microfibrillar collagen Hemostat which is also known as Avitin A-V-I-T-N-A So this is microfibrillar collagen hemostat or avitin Which is derived from purified bovine dermal collagen it is very effective against when there is capillary venous or small arterial bleeding and It attracts platelets and promote plug formation it inactivates thrombin and And But there are some potential adduous event such as allergic reactions Inflammation or potential for infection and abscess formation. So that is microfibrillar collagen hemostat and the next one in passive group that is Absorbable collagen hemostat sponge Absorbable Collagen Hemostat sponge Which is Instat Okay, this is avitin. This is instat So this is like derived from purified and Liophilized bovine dermal tendon which adheres to the surface when wet and does not stick to the instrument and Collagen sponge which gets absorbed into 8 to 10 weeks which control bleeding in 2 to 5 minutes Next we have oxidized regenerated cellulose Which is known as Surge cell, okay So this reacts with blood increase in size and form say gelatinous mass after 24 to 48 hours and promotes Claude formation So the potential complications and encapsulation of fluid then stenosis of vascular structure burning or The stinging sensations headaches all can be adverse effects Then we have the normal gelatin or gelatin or gel form So these are derived from purified bovine gelatin solutions It can be used in dry or wet form But conforms easily to wounds and therefore can be used for irregular wounds. That is gelatin or gel forms Then we have polysaccharide hemospheres Polysaccharide Spheres Okay So this is derived from vegetable starch And it contains no human or animal component. Okay, so these are the passive Topical agents So it was a first one was avitin that was a microfibre lower collagen hemostat Then the instat which is absorbable collagen hemostat sponge Then we have surge cell which is oxidized regenerated cellulose then gel form which is gelatin's and polysaccharide hemostheres. Now, let's see what are the topical agents in active category So the mechanism of active topical agents is different from passive. In passive it was like providing a physical lattice mattress which adds to bleeding site which is activating the extrinsic float pathway and platelet aggregates and formation of glute But whereas an active method it already has biological activity Biological activities Default so it participates directly at the end of coagulation cascade. So direct involvement And the coagulation mechanism That is a coagulation cascade and it stimulates Fibrillation at the bleeding site to produce a clot So thrombin acts at the end of the clotting clotting cascade Action of agent is not affected by clotting factor deficiencies or platelet malfunctions So it can also be given to patients receiving anti platelets or anti coagulant that I mean that is a waferin heparin Medicines if patient is already taking also we can use active agents So these active topical agents provide hemostasis within 10 minutes and they are more effective in controlling bleeding than the passive agents So the basic Products are thrombin products thrombin products thrombin products So the first one is bovine thrombin bovine thrombin This is an active Topical agent so bovine thrombin applied using a pump or spray kit or in a saturated absorbable gelatin sponge But the adverse effects it has antibody formation to bovine thrombin which can lead to coagulopathy allergic reactions Then we have pooled human plasma thrombin pooled human Plasma thrombin, so this is delivered saturated absorbable gelatin sponge it has risk for viral or viral disease transmission and We have Recombinant thrombin Recombinant so reduce risk of antibody formation and eliminates risk of viral transmission So that is a topical agents and we have one more category that is flowable hemostatic agents Flowable hemostatic agents so these Flowable hemostatic agents combine passive and active hemostatic agents into a single application product which work by Blocking the blood flow and actively converting fibrinogen to fibrin so Two types of products are available in flowable. One is absorbable bovine gelatin and pooled human thrombin the bovine gelatin plus pooled human thrombin and Next is porcine gelatin porcine gelatin and Any of the thrombin types what we learned previously so both the products do not contain fibrinogen and The direct contact with blood is necessary So there are some sealant products are also there in flowable Fibrin sealants Fibrin sealants are there it is Then we have polyethylene glycol polyethylene glycol polymers they are Co-seal Dura seal and Pro gel Okay, so these are the polyethylene glycol polymers and also We have albumin Gluteraldehyde this all comes under flowable hemostatic agents So these are the various hemostatic agents which comes under Flowable hemostatic agents so basically we have mechanical thermal chemical topical Which is again passive active and the last one flowable So hope you understood this topic of hemostatic agents which is very frequently asked Christian and university paper, so I'll come up with a new topic in all surgery. Thank you