Chapter 9 CoAgulation

blood naturally has?

1. Coags

2. Anticoags

Natural coagulants are for:

For small vessels only

Prevent some blood loss

Natural anticoagulants are for:

• Prevent undesired clotting in undamaged vessels

• Interfere with clotting sequence

BLANK Stages of Clot Formation

Three Stages

Stage 1: Thromboplastin

Stage 2: Thrombin

Stage 3: Fibrin

Stage 1: Thromboplastin

1. Thromboplastin is formed

Stage 2: Thrombin

2. thromboplastin converts pro-thrombin into thrombin

Stage 3: Fibrin

3. thrombin converts fibrinogen to fibrin

Stages of Clot Formation; Stage 1: Two mechanisms

1. Extrinsic

2. Intrinsic

Extrinsic—initiated by:

• Factors outside blood

• produce clot in seconds

• factors outside the blood

Intrinsic—initiated by:

• Factors contained in blood

• produces in several minutes

Examples of clot formation substances:

1. Calcium (Ca+ ) is required at all stages to enable critical steps.

2. Vitamin K is also required to synthesize several factor

Remove one substance = no BLANK = no clot

cascade

Clotting within an unbroken blood vessel is known as BLANK

thrombosis

there are BLANK options to treat thrombosis

medical and surgical

1. Blood contains fibrinolysin, a clot-dissolving enzyme medically

2. Arterial requires surgery-arterial embolectomy.

3. Venous is usually treated medically

Coagulants are?

Drugs that promote, accelerate, or make possible blood coagulation

Hemostatic Coagulants are?

topical

1. are almost exclusively used in surgical setting, enhance or control bleeding at a surgical site, used for minor capillary bleeding

2. serve as adjuncts to natural coagulation.

3. used in surgery and applied topically in the form of films, powders, sponges, or solutions.

BLANK coagulants are generally used in the medical setting

Systemic

Absorbable Gelatin should?

Should never be placed intravascularly

Who am I?

1. Animal in origin – purified porcine skin gelatin

2. Applied topically with pressure to bleeding sites

3. Absorbed completely in 4 – 6 weeks

4. Can be used dry or moistened with saline

Absorbable Gelatin

Absorbable gelatin AND Oxidized Cellulose AND Avitene MCH are agent free of side effects, but it shouldn't be used when BLANK is present

infection

1. Gelfilm

2. Gelfoam powder AND sponge

3. Gelita-Spon

4. Surgiflo / Floseal

5. Surgifoam

Absorbable Gelatin; Types

Gelfilm

dry has the consistency of stiff cellophane. Can be moistened to become pliable to used in desired shapes and sizes

(hint: letter f)

Gelfoam powder

can be made into a paste by mixing with saline. The form promotes tissue granulation so it can be used in skin ulcerations

Gelfoam sponge

comes is various sizes, can be cut

Surgiflo & Floseal

1. “flowable” conforms to uneven bleeding surfaces.

2. They come in kits that contain sterile 0.9% sodium chloride which is used to reconstitute the vial of thrombin.

3. The kit also contains a bowl to mix the thrombin and gelatin matrix. Once mixed, it should be used within 4 hours.

Who am I?

Made from purified bovine collagen

1. Cut to a desired shape and applied with pressure to a bleeding site

Absorbable Collagen Sponge

Examples of Absorbable Collagen Sponge

• Helistat

• Helitene

Collagen SPONGE may BLANK the bonding strength of methyl methacrylate, so it should not be applied to bone before placement of a prosthesis

Reduce

Microfibrillar/"Avitene" Collagen Hemostat

made from purified bovine corium collagen that comes in various forms

Microfibrillar/"Avitene" Collagen Hemostat MUST be applied using BLANK because it will adhere to wet surfaces

dry instruments

Oxidized Cellulose

Its action is not yet clearly understood, but when it’s applied to bleeding surfaces, it swells and serves as a nucleus for clotting.

Examples of Oxidized Cellulose

Surgicel, NuKnit, Gelita-Cel (100% organic, extracted from cotton)

Thrombin

Enzyme that assists in the conversion of fibrinogen to fibrin in the blood-clotting cascade

1. hemostatic agent of bovine origin

Bone Wax

It is a pliable, opaque, waxy substance that is sparingly applied directly onto bone

made from beeswax

Chemical Hemostatic

cauterize bleeding surfaces chemically

• Monsel solution

• Tannic acid

• Silver nitrate

SYSTEMIC COAGULANTS

Agents that replenish deficiencies in the natural clotting mechanism.

1. May be used to replace calcium, vitamin K, or some of the coagulation factors in the blood

CALCIUM SALTS

As the body’s most common mineral, and is crucial to many body functions, including blood coagulation

Remember that ______ is crucial throughout the cascade

VITAMIN K

fat-soluble vitamin that promotes blood clotting by increasing prothrombin synthesis in the liver

Coumadin is

Antagonist for Vitamin K

If Vitamin K is needed, it can be administered by subcutaneous injection BLANK preoperatively

6 to 24 hours

BLANK blood factors administered intravenously

two factors

1. VIII (AHF)

2. IX complex

IX complex

Factor IX complex may be administered preoperatively to patients with hemophilia B

VIII (AHF)

Preoperatively, coagulation factor VIII is administered to patients with hemophilia A

Anticoagulants

agents that prevent or interfere with coagulation

1. Used in surgery to help prevent clot formation as a response to trauma or manipulation of blood vessels

Anticoagulants BLANK dissolve existing clots – Thrombolytics dissolve EXISITING clots

DO NOT

What do anticoags prevent?

1. Pulmonary Embolism (PE), acute coronary occlusions after myocardial infarction (MI), and strokes

2. Thrombosis

Parenteral Anticoagulants

Drugs administered intravenously, subcutaneously, or topically. Prevent or interfere with clotting

Heparin

BLANK – the most commonly used parenteral anticoagulant intra-op

Antagonist for Heparin

Protamine Sulfate

Low-Molecular-Weight Heparins (LMWHS)

Smaller molecules used for same purposes as regular heparin

Enoxaparin (Lovenox)

• Prevents deep vein thrombosis (DVT) following abdominal surgery or hip or knee replacement

• Medical, not surgical, use

(hint: x = do not cut)

Arista

Topical hemostatic agent example?

(hint: skin)

Arixtra

Anticoagulant example?

ORAL Anticoagulants

• Long-term management of thromboembolic disease

• PE, DVT, cardiovascular accident (CVA)

What inhibits vitamin K activity in liver?

Warfarin/"Coumadin"

Aspirin - Acetylsalicylic Acid (ASA)

Prevents clot formation by inhibiting platelet aggregation

NOT for use concurrent with warfarin (Coumadin) therapy

Normal bleeding time may be doubled

Alteplase ("Activase")

It’s a biosynthetic form of a naturally occurring enzyme, human tPA

Thrombolytics

Anticoagulant therapy may be used in conjunction with BLANK agents