2. The rate of transfusion may be increased to 10 to

20 mL/kg/h to replace acute blood loss.

3. 120 to 150 micron inline filters often used for complex

mechanical procedure.

Platelet Transfusions

A. Indications (Table 43.3)

The platelet count at which transfusion is recommended

has to be individualized because hemostatic competence is

determined not only by the quantity of platelets but also by

platelet function, vascular integrity, levels of coagulation

factors, and underlying disorder/disease.

B. Contraindications (33)

1. Autoimmune thrombocytopenic purpura (neonatal

ITP)

2. Heparin-induced thrombocytopenia (HIT)

3. Bleeding due to coagulopathy only (i.e., vitamin K deficiency)

4. Bleeding due to anatomic defect

5. Bleeding controllable with direct pressure/local measures (i.e., surgical bleeding)

C. Precautions

1. Use type-specific (Rh-negative) platelets when potential

for sensitization is present (i.e., in Rh-negative female).

Although platelets do not have Rh antigens, all products have some RBC contamination (less in plateletpheresis), which may cause Rh sensitization (34).

2. Use platelets from donor with ABO-compatible plasma.

Isohemagglutinins in ABO-incompatible plasma may

result in hemolysis, a positive direct antiglobulin test,

and poorer in vivo platelet survival than anticipated.

3. Transfuse platelets as soon after preparation as possible. Platelets should never be refrigerator-stored or

warmed.