Bleeding Flashcards
What is coffee ground vomit?
Blood has been in contact with gastric acid
This causes the iron in the haem to be oxidised forming what looks like ground coffee
It indicates upper GI bleed
How is haemorrhage classified?
ATLS classification which calculates a % blood loss based on observations: HR, BP, UO, RR, pulse pressure
Type 1: up to 15%
Type 2: 15-30%
Type 3: 30-40%
Type 4: over 40%
What are the aims of resuscitation?
To carry out and maintain ABCDE
Provide optimal blood flow to maintain tissue and organ perfusion
BUT
Not too high that it causes dilution of coagulation factors etc, exsanguination or dislodge a clot
What problems can over-resuscitation with fluid cause?
Exsanguination: too much fluid, too high a BP
Dilutes the coagulation factors, platelets, Hb
Dislodge a clot that’s sealed a wound
What is DIC? Explain the pathophysiology.
Disseminated intravascular coagulation
Normally there’s a balance between new clots forming and fibrinolysis
THROMBOSIS
In serious illness there is release of pro-coagulant which tips balance in favour of clot formation
Widespread clot formation in medium and small blood vessels –> ischaemia, necrosis, damage
BUT ALSO BLEEDING
Depletion of platelets and coagulation factors (all used up!)
Fibrinolysis is trying to keep up. Fibrin degradation (the product of fibrinolysis) is released which interferes with clot formation
So there’s thrombosis and bleeding at the same time
Describe the normal process of haemostasis.
Including primary, secondary and breakdown.
PRIMARY
- Vasoconstriction
- Platelets adhere to vessel wall, activate other platelets, form platelet plug
SECONDARY
- Clotting factors are always circulating in inactive form
- Coagulation cascade starts when first factor is cleaved
- Cascade happens!
- The final stage of cascade is activation of fibrin from fibrinogen
- Fibrin forms a mesh over platelets forming a clot
BREAKDOWN
- As soon as a clot is formed the body starts to break it down to prevent it getting too big (fibrinolysis)
- Produces degradation products such as D dimer
How is DIC treated?
Call the haematologist!
Treat the cause
Transfusion of platelets or plasma
What conditions can cause DIC?
Blood transfusion reaction
Trauma
Cancer, especially certain types of leukemia
Pancreatitis
Sepsis
Liver disease
Pregnancy complications
What blood products can we use to reverse coagulopathy? What do they each contain?
Red blood cells!! (none of the below work if there are no RBCs)
Platelets
Fresh frozen plasma (clotting factors, albumin)
Prothrombin complex concentrate (Beriplex)
Cryoprecipitate (factor VIII, fibrinogen)
Many more!
How much does 1 unit of blood raise Hb by?
1g/dL
Define massive haemorrhage and massive transfusion?
Massive haemorrhage:
- loss of one total blood volume within 24hr
- more than 150ml/min
- 50% total blood volume loss in 3hrs
Massive transfusion:
- transfusion of at least one blood volume over 24hrs
What is the lethal triad?
Acidosis
Hypothermia
Coagulopathy
What are some complications with massive transfusion?
Hypothermia Acid/base derangements Electrolyte abnormalities Citrate toxicity Immunosupression Dilution coagulopathy
Causes of upper GI bleed?
Peptic ulcer Oesophagitis, gastritis Varices Malignancy Mallory- Weiss tear
What is a Mallory Weiss tear?
A tear in the mucosa where oesophagus meets stomach
