Management of Hemorrhage in Oral Surgery – Key Concepts

These flashcards cover definitions, physiological mechanisms, classifications, diagnostic tests, and local/systemic control methods for hemorrhage management in oral surgery.

What is the definition of hemorrhage?

Escape of blood from blood vessels; synonymous with bleeding.

Why can hemorrhage vary in severity during surgery?

Because it depends on whether the patient’s clotting mechanism is normal or abnormal.

Name the three phases of normal hemostasis.

Vascular phase, platelet phase, and coagulation phase.

What happens during the vascular phase of hemostasis?

Vasoconstriction follows damage to blood vessels.

Describe the platelet phase of hemostasis.

Platelets adhere to the damaged surface and form a temporary plug.

What major event defines the coagulation phase?

Conversion of fibrinogen to fibrin via intrinsic and extrinsic pathways to form a stable clot.

Which pathway of coagulation is triggered by collagen exposure?

The intrinsic pathway.

Which pathway of coagulation is triggered by tissue thromboplastin?

The extrinsic pathway.

List five key factors that affect hemostasis.

Vascular integrity, platelet quantity, platelet quality, adequate clotting-factor levels, proper fibrinogen pathway function.

Give two characteristic features of arterial hemorrhage.

Pulsatile, brisk flow of bright red blood.

What color and flow pattern are typical of venous hemorrhage?

Dark red blood that flows steadily in an even stream.

How does capillary hemorrhage usually present?

Bluish bright-red oozing that is controlled by simple pressure.

Define primary hemorrhage.

Bleeding that occurs at the time of injury or surgery and lasts a short duration.

When does reactionary hemorrhage occur, and give one cause.

Within a few hours after surgery; caused by clot dislodgement or systemic coagulation problems/anticoagulants.

What is secondary hemorrhage, and list one common cause.

Bleeding 4–10 days after surgery; often due to wound infection.

Differentiate internal and external bleeding.

Internal is confined to body cavities; external is visible on skin or mucosal surfaces.

What two broad tissue sources can bleeding originate from in oral surgery?

Bony and soft-tissue hemorrhage.

Name four history elements important in hemorrhage assessment.

Demographic data, family history, dental history, past surgery history.

Mention three clinical signs suggesting systemic bleeding disorders.

Petechiae, ecchymosis, telangiectasia (others: splenomegaly, hepatomegaly, etc.).

What is petechiae?

Small pinpoint mucocutaneous hemorrhages indicating capillary bleeding.

State the normal bleeding time.

Less than 10 minutes.

Give the normal platelet count range.

150,000–450,000/mm³.

Which coagulation test evaluates the extrinsic pathway?

Prothrombin time (PT).

Name three factors assessed by PT.

Factors V, VII, and X (also I and II).

List two causes of prolonged PT.

Warfarin therapy or vitamin K deficiency (also factor deficiencies).

What is the normal PT value?

12–14 seconds.

Which test evaluates the intrinsic pathway?

Partial Thromboplastin Time (PTT).

State three local mechanisms that naturally control hemorrhage.

Vessel contraction, retraction, and clot formation.

What is the simplest mechanical method to stop bleeding locally?

Firm pressure with gauze for about 5 minutes.

Give two uses of hemostats in bleeding control.

Clamping vessels for ligation or serving as a conductor for electrocautery.

What is embolization and name one material used.

Blocking a bleeding vessel via angiographic catheter; example agents: steel coils, PVA foam, etc.

How does cautery achieve hemostasis?

Heat denatures tissue proteins, coagulating large areas.

What principle underlies electrosurgery?

Heat from an alternating current induces coagulation at the bleeding point.

At what temperature range does cryosurgery operate, and what is its effect?

–20 °C to –180 °C; causes cryogenic necrosis of tissue and vessels.

State one key precaution when using an argon beam coagulator.

Keep the tip ~1 cm from tissue to avoid gas embolism.

How do astringent agents like Monsel’s solution work?

Precipitate proteins to promote clot formation.

What is the function of bone wax?

Mechanical occlusion of bleeding bony canals.

How does topical thrombin aid hemostasis?

Converts fibrinogen to fibrin at the bleeding site.

Describe the action of gelatin sponge (Gelfoam).

Absorbs blood, swells to exert pressure, and provides a scaffold for fibrin clot.

Why is Oxycel not suitable on epithelial surfaces?

It inhibits epithelialization despite forming clots via oxidized cellulose.

What advantage does Surgicel have over Oxycel?

It does not inhibit epithelialization while still stabilizing the clot.

List the main components of fibrin glue.

Thrombin, fibrinogen, Factor XIII, and aprotinin.

Why is adrenaline applied topically during surgery?

To induce local vasoconstriction and reduce bleeding.

When is whole-blood transfusion indicated in oral surgery hemorrhage?

Massive blood loss with hypovolemic shock when blood components are unavailable.

How long is platelet-rich plasma (PRP) viable after collection?

Approximately 3 days.

Name two key coagulation factors supplied by one unit of fresh frozen plasma (FFP).

About 200 µ of Factor VIII and 200 µ of Factor V (also ~400 mg fibrinogen).

What does one 15 ml vial of cryoprecipitate provide?

~100 µ Factor VIII, 250 µ fibrinogen, and von Willebrand factor.

How does ethamsylate reduce surgical bleeding?

Improves abnormal platelet adhesion and reduces capillary bleeding with normal platelet counts.

Which anesthetic strategy can lower intra-operative bleeding?

Use of hypotensive anesthesia.