Blood Transfusion in ICU


  • anaemia common in ICU
  • tendency to more restrictive strategy c/o increased morbidity associated with transfusion
  • general attempts to minimize the requirement for blood transfusion should be pursued


  • stopping bleeding early
  • stop unnecessary anticoagulation and antiplatelet agents
  • minimising venesection
  • use blood conservation devices when sampling from arterial lines
  • correct the lethal triad of hypothermia, acidosis and coagulopathy
  • GI prophylaxis and enteral nutrition
  • haemantinics: Fe2+, B12, folate, nutrition
  • use tranexamic acid early in traumatic haemorrhage
  • consideration of EPO therapy
  • consider use of FVIIA


Transfusion triggers are dependent on many variables:

1. evidence of bleeding and stability of patient
2. reason for admission (trauma, GIH)
3. patient wishes (Jehovah’s witness)
4. comorbid conditions (such as ischaemic heart disease)


Other controversial issues include the prophylactic use of erythropoeitin, routine use of filters / leukodepletion of red cells prior to transfusion, reinfusion of autologous blood (eg cell saver), and the approach to those patients unwilling to be transfused.  A strategy should also be in place to deal with the potential complications associated with massive transfusion (eg coagulopathy).

  • lower threshold to transfuse
  • adults: aim to keep Hb > 100 g/L until bleeding controlled
  • trauma patient:

-> haemostatic resuscitation: early products in a 1-2:1:1 ratio (RBC:platelets:plasma)
-> permissive hypotension
-> damage control surgery
-> avoid hypothermia, acidosis and coagulopathy


  • based on TRICC 1999 and current NBA guidelines in transfusion in critical care:
    — Hb <70 is usual trigger for transfusion (though patients who are well compensated may not need transfusion)
    — 70 to 100 should be transfused if evidence of ischemia or impaired oxygen delivery
    — Hb >100 rarely if ever need transfusion
  • post CAGS Hb 80 is non-inferior to Hb 90
  • higher thresholds if elderly or ischemic heart disease (e.g. Hb 100)
  • permissive approach also shown to be acceptable in hip fracture patients

TRICC trial (NEJM, 1999)

  • critically ill, normovolaemic, non-bleeding
  • MRCT
  • n = 838
  • restrictive (70g/L) vs liberal groups (100g/L) as transfusion thresholds
  • no difference in mortality
  • increased complications in liberal strategy group (APO, ARDS)
  • under powered (so the study was unlikely to find a difference anyway)
  • prior to leukodepletion

TRACS trial (JAMA, 2010)

  • post cardiac surgical patients
  • RCT
  • n = 502
  • HCT 30% vs HCT > 24%
  • no difference in mortality and severe morbidity
  • large separation between groups not achieved
  • high base line event rate
  • number of RBC’s transfused was an independent risk factor for clinical complications


Storage lesions

  • transfusion of RBCs >2-3 weeks old may have additional risks due to storage lesions
  • See Storage Lesions


  • all RBCs for transfusion in Australia and New Zealand are now leukodepleted
  • this is thought to decrease many transfusion risks; the highest quality evidence available is based only on observational data
  • See Leukodepleted blood


  • decreases transfusion requirements
  • increased thrombotic complications
  • being investigated in trauma and traumatic brain injury


  • stops bleeding but increased risk of thrombosis and embolic disease

Undefined threshold for IHD patients

  • ? Hb target of 100

Use of autologous blood if possible

  • use cell saver device

Patients who refuse transfusion (e.g. Jehovah’s Witnesses)

  • prevent bleeding and anemia
  • consider EPO
  • consider blood substitutes


  • minimise transfusion requirements using other means
  • if bleeding: transfuse aggressively until bleeding controlled (avoid hypothermia, acidosis and coagulopathy).
  • if not bleeding: restrictive strategy in those who can tolerate it and more liberal in those that have evidence of ischaemic end-organ dysfunction.
  • ideally use new, leukodepleted blood

References and Links


FOAM and web resources

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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