Blood Tranfusion Flashcards
Blood products
Indications:
A) Whole blood: The only option for the first 250 years of transfusion history, but now rarely used.
B) Red cells: (Packed to make haematocrit ~70%.) Use to correct anaemia or blood loss. lu tHb by 10-15g/L. In anaemia, transfuse until Hb ~80g/L.
C) Platelets: (p364.) Usually only needed if bleeding or count is <20 × 10%/L lu should platelet count by >20 × 10°/L. Failure to do so suggests refractory cause: discuss with haematologist. If surgery is planned, get advice if count is <100 × 10%/L
- Platelets:
1- Traumatic bleeds, purpura, and easy bruising occur if platelets <50109/L.
2- Spontaneous bleeding may occur if platelets <20109/L, with intrac- ranial haemorrhage rarely. - Platelets are stored at room temperature (22°C; not in the fridge).
- In marrow transplant or if severely immunosuppressed, platelets may need irradiation before use to prevent transfusion-associated GVHD.
- Platelets must be ABO compatible.
- They are not used in ITP (p345).
• Platelets <10109/L.
•Haemorrhage (eg DIC, p352).
•Before invasive procedures (eg biopsy, lumbar puncture) to increase count to >50109/L. 4U of platelets should raise the count to >40*109/L in adults; check dose needed with lab.
D) Fresh frozen plasma (FFP): Use to correct clotting defects: eg
- DIC (p352);
- warfarin overdosage where vitamin k would be too slow;
- liver disease;
-thrombotic thrombo-cytopenic purpura (p315).
It is expensive and carries all the risks of blood transfu-sion. Do not use as a simple volume expander.
E) Human albumin solution is produced as 4.5% or 20% protein solution and is used to replace protein. 20% albumin can be used temporarily in the hypoproteinaemic patient (eg liver disease; nephrosis) who is fluid overloaded, without giving an excessive salt load. Also used as replacement in abdominal paracentesis (p765).
