Hemorrhage and Haemodynamics

Question 1

What is haemodynamic?

Answer 1

• The physiology of blood flow and the forces involved in circulation

Question 2

How is Haemodynamic measured?

Answer 2

• HR, BP, perfusion

Question 3

What is the two-part process of perfusion?

Answer 3

• Oxygen and nutrients go in and waste comes out

Question 4

What is oxygenation?

Answer 4

• Oxygen reaching a tissue or cell

Question 5

What three components of the body need to be functional and working adequately for the body to perfuse?

Answer 5

• Lungs, heart and Vessels

Question 6

Lung Perfusion

Answer 6

• Adequate O2 reaching alveoli

- Adequate oxygenation and ability to diffuse across the alveoli membrane

Question 7

What are all vasculature lined with?

Answer 7

• Smooth endothelial cells

Question 8

What mechanisms are a feature of vessels bigger than capillaries?

Answer 8

• They have elastic layers, tunicae, these regulate pressure

Question 9

What determines the nature of flow through the body?

Answer 9

• The difference in pressure at two ends of a vessel.

Question 10

Define Haemorrhage.

Answer 10

-	Disruption or leakage from the circulatory system, it can be broken down into three subtypes.
o	External
o	Internal (concealed)
	Bleeding into tissue or organs, but not visible
o	Internal (revealed)
	Becomes visible through passage or orophas of the body.

Question 11

What types of external haemorrhage may occur?

Answer 11

• Arterial
  o Will be seen as pulses, and spurts of bright red blood, denoting that it is oxygenated
• Venous
  o Will be a steady flow from the wound and will present with a dark red colour, denoting that it is deoxygenated.
• Capillary
  o Small volume of blood and will ooze out

Question 12

What determines how serious a haemorrhage is?

Answer 12

the amount of the vasculature is disrupted and the amount of blood loss.

Question 13

What body cavity will an internal haemorrhage from illness, disease or rupture tend to occur in?

Answer 13

• Chest
• Abdomen
• Pelvis
• Retroperitoneal
• Skull

Question 14

What is the natural control of bleeding?

Answer 14

• Haemostasis, the prevention of blood loss.

Question 15

What are platelets function in the clotting mechanism?

Answer 15

• Forming a temporary plug that helps seal breaks or ruptures that have occurred in blood vessels.

Question 16

What is the clotting process?

Answer 16

• A injury occurs, LAC, Blunt injury etc.
• Vascular spasm occurs
  o This is to reduce the level of blood lost through the hole
• Platelet plug formation
  o Clotting cascade occurs
• Blood coagulation
  o The formation of scabs and scars

Question 17

Platelet plug formation

Answer 17

• Platelets adhere to the collagen under the epithelium
• Platelets become enlarge and irregular
• Platelets become sticky and attracts other platelets forming a temporary plug

Question 18

Blood coagulation

Answer 18

• Blood coagulation is a complex process, it not only involves platelets but also substances that secrete vessel walls and blood proteins that initiate clotting.

Question 19

What pathways are involved in the clotting process?

Answer 19

• Extrinsic and intrinsic pathways

Question 20

Explain the Extrinsic pathway

Answer 20

• The extrinsic pathway takes effect within seconds of damage occurring.
• It is initiated with liquid blood contacting damaged tissue.
• It starts with damage to the vessel wall and surrounding tissue

Question 21

Explain the Intrinsic pathway

Answer 21

• The intrinsic process is initiated by liquid blood contacting a foreign surface, i.e. something that is not a part of the body, occurs minutes after the wound has occurred.

Question 22

What are the stages of the common pathway?

Answer 22

-	Stage one
o	Formation of prothrombin activator
-	Stage two
o	Conversion of prothrombin
-	Stage three
o	Conversion of soluble fibrinogen

Question 23

How does the formation of Pro thrombin activator occur?

Answer 23

• The process occurs differently in the intrinsic and extrinsic pathways.
• Involves the activation of 4 other factors.

Question 24

What is factor 1?

Answer 24

• Fibrinogen

Question 25

What is factor 2>

Answer 25

- Prothrombin

Question 26

What is Factor 3?

Answer 26

- Tissue thromboplastin

Question 27

What is Factor 4?

Answer 27

- Calcium

Question 28

What is Factor 5?

Answer 28

- Proaccelerin labile factor: AC-globulin

Question 29

What is factor 8?

Answer 29

- Antihemophilic factor | - Antihemophilic Factor A

Question 30

What is Factor 10?

Answer 30

- Stuart Factor, Stuart-power factor.

Question 31

How does clot retraction and Dissolution work?

Answer 31

- As the cloth retracts, it pulls the edges of the broken blood vessel together, opening the blood vessel and increasing the blood flow.

Question 32

What is Fibrinolysis?

Answer 32

- The break down of the clot so that the vessels don’t become blocked. o Occurs through the breakdown of fibrin.

Question 33

What forms of drugs have an effect on clotting?

Answer 33

- Platelet inhibitors o Aspirin – Stops production of thromboxane A, required in platelet plug formation.  Prevents the clot growing larger. - Anticoagulants o Warfarin – Interferes with Vitamin K dependent clotting factors, for example, prothrombin (factor 2). - Streptokinase – convert plasminogen into active plasmin o Clot dissolving

Question 34

What patient pathologies may affect the clotting process?

Answer 34

- Excessive bleeding. - Liver disease o Preventing the synthesis of clotting factors - Vitamin K deficiency o Required for clotting factor synthesis - Haemophilia o Commonly due to deficiency of factor VIII (Antihemophilic factor), Haemophilia A - Thrombocytopenia o Abnormally low levels of circulating platelets - Von Willebrand’s disease o Compound defect involving both platelet function and clotting factor deficiency. - Thromboembolic conditions o Unwanted clots are formed - Disseminated intravascular coagulation DIC o Spontaneous clots form as a failure of multiple systems.  These create blocked blood flow and may create severe bleeding.

Question 35

What types of internal haemorrhage can be considered?

Answer 35

- Haematemesis - Haemoptysis o Associated with tuberculosis or cancer - Haematuria o Related to trauma of urinary tract and kidney stones - Vaginal bleeds o Spontaneous abortion, intrapartum haemorrhage - Rectal bleeds o heemraads - Melaena o Dark and highly offensive smell Stools. Indicative of ulcer/tumour. Small and upper GIT bleeds.

Question 36

How might a patient with an internal haemorrhage present?

Answer 36

- Light headed - Nausea or vomiting - Rapid, weak, thready pulse - Rapid respirations - Pale, cold, and clammy - Thirsty

Question 37

What are exceptions of bad cavity bleeds?

Answer 37

- Menstruation - Haemorrhoids - Some epistaxis

Question 38

What is the treatment of Epistaxis?

Answer 38

- Firm pressure to the soft part of the nose for 10 minutes - Sit upright, head forward - Don’t blow the nose o This will disturb the clotting process - Cold compress on the back of the neck - If bleed continues for > 10 minutes transport