Transcript Fluids and blood products in trauma

Fluids and blood products in trauma
Acute Care Day
Importance
• The two leading causes of death in
trauma are neurological injury and blood
loss
• There is much current research into
optimum fluid therapies in trauma
• There are some differences to major
haemorrhage from other sites
Reasons for debate – competing priorities
Maintain perfusion
• Good tissue perfusion is
dependent upon a good
cardiac output
• Cardiac output is
augmented by high filling
pressures – need blood
volume
• A decent blood pressure
is needed to overcome
tissue resistance
• Solution: give lots of
fluids and blood
Maintain coagulation
• High BP can dislodge
forming clots, leading to
continued clotting factor
consumption
• IV fluids and red-cells
dilute clotting factors
• Fluids can cool a patient
– clotting factors work
less well
• Solution: don’t give any
fluid or blood!
What’s the solution?
• Some middle ground is needed.
• What is worse – hypoperfusion or
coagulopathy?
How bad is hypo-perfusion
• Hypo-perfusion leading to tissue
ischaemia can impair the function of all
organs
• Tissues may start to respire anaerobically,
producing lactic acid.
• Acidosis adversely affects enzymatic
action – including the clotting cascade
• However, the effects of short periods of
relative hypo-perfusion are usually fairly
rapidly correctable
How bad is coagulopathy?
• Trauma patients can have multiple sites of
blood loss that are not immediately
controllable – ie. may need surgery or
interventional radiology to cease bleeding.
• If coagulopathy develops, bleeding is
exacerbated.
• This then worsens any hypoperfusion 
anaerobic respiration and acidosis.
• You need to play “catch-up” – transfusing
blood products which can cool the patient
The Lethal Triad
Coagulopathy
Acidosis
Cold
What’s the solution then?
• A degree of hypo-perfusion is tolerated in
the acute setting, until haemorrhage
control has been achieved.
• In practice, this means a conscious
patient with a palpable radial pulse and a
systolic blood pressure of at least
80mmHg
• If these criteria are not met, 250ml
boluses of fluids (eg. Hartmanns) can be
given to boost blood pressure
• Coagulopathy should be aggressively
avoided.
When should you start giving blood?
• No set rule – but in general you should try
and use as little crystalloid as possible –
certainly give blood if approaching 1 litre
of crystalloids
• Crystalloid versus colloid debate: currently
raging, but there appears to be minimal if
any benefit in giving colloids
• If a trauma patient needs volume
replacement, try to make as much of it
blood as possible.
What blood products are there?
Whole
Blood
Platelets
Fresh Frozen
Plasma
Cryoprecipitate
Red blood cells
• Three options:
- O negative. Available immediately in A&E
or blood bank.
- Group specific. Takes about 15 minutes
from receipt of sample in lab.
- Fully cross-matched. Takes about 40
minutes from receipt of sample in lab.
Red blood cells
• Oxygen carrying component, so most
important aspect of blood.
• However, the bags contain no clotting
factors or platelets.
• These factors must also be replaced.
Fresh Frozen Plasma
• This contains all clotting factors
• Not usually administered until the patient
has received at least 4 units of red cells
Platelets and cryoprecipitate
• Cryoprecipitate – contains a few clotting
factors, but main component is fibrinogen
• These each contain multiple units within
one bag. Bags of these are not usually
given until about 8 units of red cells have
been transfused
• Liaise with haematology regarding
ongoing blood product management.
Is this going to change??
• Evidence from the military supports a
more liberal usage of FFP, platelets and
cryoprecipitate.
• Suggest using 1 unit of FFP with every 1
or 2 units of red cells.
• This is not current practice in UK
hospitals….but things may change!
Clotting augmentation
• Fibrinolysis is the process of clot lysis
• Tranexamic acid is an anti-fibrinolytic: it
inhibits clot breakdown
• It is cheap and very safe
• Good evidence that administering this to
bleeding trauma patients reduces their
mortality. Give this with your first unit of
blood.
Clotting optimisation
• The clotting cascade is a series of
enzymes
• They work best at normal body
temperature and pH
• Critically important to maintain these –
warm all blood products, keep patient
covered.
• Clotting factors also need calcium – levels
can drop in major haemorrhage, so top up
if necessary
What happens once bleeding has stopped?
• Definitive control of bleeding is usually
surgical.
• Once achieved, priority shifts from
coagulation maintenance to perfusion
maintenance
• Aim for higher blood pressure, be more
liberal with administration of blood
products. May also give some IV fluids.
Summary
• Blood and fluid therapy in trauma is not
straight-forward
• Perfusion can be relatively sacrificed to
maintain coagulation
• Try to minimise use of crystalloids or
colloids – especially if large blood loss is
anticipated
• Avoid development of the lethal triad:
cold, acidosis and coagulopathy