Discuss the management of massive blood loss in a hospital setting
Massive blood loss
Definition
- 1 blood volume within 24 hours (Adult blood volume 7% of ideal body weight ie. about 5 litres)
- 50% blood volume within 3 hours
- >150ml/minute
General principles
- Maintain tissue perfusion and oxygenation
- Arrest bleeding
- Correct coagulopathy with blood products
Communication
- Between haematology and clinical specialties (surgery, anaesthetics, interventional radiology for embolisation), lab, blood service,
- Dedicated team member to co-ordinate
- Early senior involvement
Local protocols – role of the hospital transfusion committee
- Other roles include analysis of events
- Contingency plan for national blood shortage and emergencies
General principles
- Restore circulating volume / monitor signs of poor tissue oxygenation
- Venous access
- Warming of fluids and blood products (hypothermia increase coagulopathy)
- Monitor UO/ BP
- Treat acidosis
- Arrest bleeding
- Surgical/ obstetric / interventional radiology
- Investigations
- Group and Ab screen
- Baseline haem, coag and biochemistry
- Consider near patient testing such as TEG
Haematology targets
1. HB >8
- Consider cell salvage
- O neg in emergency - ABO group specific – fully cross matched
- Use blood warmer, rapid infuser (level 1)
- HCT 0.35 may be required to sustain haemostasis in massive blood loss
- 30-40% blood loss, PRCs usually required
2. Plts >75 (margin of safety, shouldn’t fall below 50)
- Anticipate plt <50 after 2 x blood volume replacement
3. PTT and APTT <1.5
- FFP 12-15mls/ kg (1L in adults)
- Anticipate need after 1-1.5 x blood volume - now probably would instigate earlier particularly if there has been trauma or there is pre-existing coagulopathy. Concept of 1:1 FFP to blood ratios.
- Lasts for 24 hours once thawed, therefore should start to dethaw immediately
- 30 minute thaw time
1. Fibrinogen >1
- 2 packs for an adult, usually only needed if DIC
- 30 minute thaw time
Other agents
- PCC if secondary to warfarin
- Not enough evidence to support antifibrinolytics
- rVIIa – off license, consider if continued bleeding despite correction of other parameters
- Fibrinogen concentrate
Risks
- Wrong unit transfused
- DIC – cardinal sign is microvascular oozing
- Hypocalcaemia, hyperkalaemia, TRALI