Page 567 - ACCCN's Critical Care Nursing

544 P R I N C I P L E S A N D P R A C T I C E O F C R I T I C A L C A R E

• Trauma
• Surgery
Major haemorrhage • Post partum haemorrhage
• GI bleed
• Ruptured aortic aneurysm

• Mild (750mL)
Blood loss • Moderate (750-1500mL)
• Severe (1500+)

• Massive transfusion
protocol (including dose,
Massive timing, ratio of
transfusion RBC’s:FFP:Platelets and
required
when to consider
factor Vlla)

FIGURE 20.2 Indications for massive transfusion.

haemorrhage. Careful consideration of a patient’s clinical severe hypovolaemia is suspected then blood is often
picture will establish a hierarchy and priority of needs. used to improve oxygen-carrying capacity. Further dilu-
Most hospitals have some level of track and trigger tion of blood by volume expanders increases hypoxia
response that escalates care to appropriate levels (e.g. (otherwise known as isovolaemic anaemia) and red cells
MET calling criteria), however nurses are in a position to are usually needed. Use of isotonic saline as a volume
establish first line management such as intravenous expander is common, although resuscitation with large
access where this is a required skill. There are also many volumes of saline solutions can be associated with hyper-
examples of protocols and guidelines for nurses to initi- chloraemic acidosis. Blood and blood components are
40
ate fluid resuscitation where a patient has indications of usually considered necessary where patients exhibit signs
inadequate circulating blood volume; e.g. a fluid bolus up of moderate to severe haemorrhage (see Figure 20.2).
to 20 mL/kg of colloidor 30–40 mL/kg crystalloid may be There is no perfect resuscitation fluid, and selection is
recommended (depending on organisational guidelines). guided by patient condition and the type of fluid lost.
There are a number of factors to consider when admin-
Collaborative Management istering blood products in massive volume. Massive trans-
Selection of the appropriate fluid indications for surgical fusion is defined as replacement of a patient’s total blood
management and ‘permissive hypotension’ (deliberate volume in less than 24 hours (approximately 10 units of
48
limiting or minimising resuscitation until after adequate red cells); 47,48 although the literature is inconsistent. A
surgical control of haemorrhage). 40,42 will be assessed number of complications are evident (e.g. transfusion
3
by the multidisciplinary team. Goal-directed therapy reactions, coagulopathies, hypothermia, sepsis) and is
48
includes prevention of tissue hypoxia, typically through associated with high mortality. Patients receiving
rigorous fluid resuscitation with either crystalloids or col- massive blood transfusions require careful monitoring
loids to achieve specific haemodynamic endpoints (e.g. a for signs of metabolic derangements, hypothermia, citrate
CVP of 8–12 mmHg, MAP >70 mmHg, urine output toxicity, hyperkalaemia and coagulopathies (due to deple-
>0.5 mL/kg/h). Vasopressor and inotrope therapy may be tion of clotting factors). Dilution and clotting factor con-
then added to maintain adequate perfusion pressure; sumption cause microvascular bleeding, often manifesting
noradrenaline is the vasopressor of choice because of as oozing from multiple sites even after surgical correc-
vasoconstrictor effects. 43 tion. 47,48 Massive transfusion of stored blood with high
oxygen affinity adversely affects oxygen delivery to the
Preload management tissues. It is therefore preferable to transfuse blood cells
The colloid versus crystalloid fluid resuscitation debate that are less than 1 week old; 2,3-diphosphoglycerate
(use of albumin-based solutions or colloids) continues levels rise rapidly after transfusion, and normal oxygen
despite findings from the SAFE study conducted in Aus- affinity is usually restored within a few hours of
47
tralasia; crystalloids (isotonic saline based solutions) transfusion.
were as effective as colloids for fluid resuscitation. 44–46 The Each unit of blood contains approximately 3 g of citrate,
scientific rationale for using colloids over crystalloids is which binds to ionised calcium. A healthy adult liver
to preserve plasma oncotic pressure so as to retain intra- metabolises 3 g of citrate every 5 minutes. If blood is
vascular fluid and minimise oedema. Colloids may also transfused rapidly or the liver is impaired, citrate toxicity
20
attenuate the inflammatory response. If moderate to and hypocalcaemia may develop. The patient should