Haemorrhage Flashcards
What is haemorrhage?
Loss of blood from a circulatory system due to traumatic disruption of blood vessels
Why do many surgeons make huge effort to prevent and control haemorrhage?
Because the presence of blood in the operating field obscures the view of the surgical site and increases the difficulty of the surgery
What are the deleterious effects of haemorrhage
- Obscures the surgical field and slows surgery
- Increases chance of wound infection
- clotted blood is an ideal bacterial medium - Creates a barrier to healing
- Compromises patient circulatory status
- can lead to shock
What does a haematoma do?
- Creates space and occupies it
- Prevents correct tissue approximation and healing
What is primary haemorrhage?
Occurs immediately after trauma to blood vessel
What are the body’s initial local defense mechanisms against haemorrhage?
- Vasoconstriction
- Platelet plug formation, the fibrin clot via intrinsic coagulation cascade
- Changes in intra and extr luminal pressure
What are the body’s initial systemic defense mechanisms against decreased blood volume?
- Vasoconstriction of skin
- Increased heart rate
- Interstitial fluid movement into vascular space
What are the clinical signs of the body’s initial response to haemorrhage?
- Pale mucous membranes and skin
- Cold extremities
- Tachycardia
- Deep, rapid respirations
- Decreased pulse pressure as systolic pressure diminishes
- Depressed and immobile patient
- Swollen surgical site
What occurs in the body later after prolonged haemorrhage?
- Fluid conservation
- The RAA system promotes Na+ conservation
- ADH is released from the posterior pituitary gland causing water resorption
- Thirst stimulus at medullary centres
How is haemorrhage classified?
- Arterial, venous or capillary
- External or internal
- Primary, intermediate or secondary
How do you differentiate between arterial, venous and capillary haemorrhage?
Arterial: Bright red spurting blood
Venous: Darker, less vigorous and not spurting
Capillary: Oozing
How do you differentiate between internal and external haemorrhage?
External: bleeding through the surface of the body
Internal: blood which accumulates within the body
How do you differentiate between primary, secondary and intermediate haemorrhage?
Primary: occurs immediately after vessel is opened
Intermediate: Bleeding within 24 hours of trauma
Secondary: occurs at least 24 hours after the vascular injury
What are the signs of a post-op infection?
- Pale Mucous Membranes
- Cold extremities
- Tachycardia
- Deep respiration, tachypnoea
- Poor pulse pressure
- Depressed patient
What do you do if a blood vessel cannot be avoided in surgery?
Recognise it prior to transection
Ligate it and divide it between the ligatures