Rx for Hemolytic Reaction

Rx  FOR HEMOLYTIC REACTION

As a result of gross exposure to a hypotonic environment.

Hemolysis of blood samples. Red blood cells without (left and middle) and with (right) hemolysis. If as little as 0.5% of the red blood cells are hemolyzed, the released hemoglobin will cause the serum or plasma to appear pale red or cherry red in color. Note that the hemolyzed sample is transparent, because there are no cells to scatter light.

I.    PROCESS:

A.    What happens to the Erythrocyte?

1.    Red blood cells  suspended in a hypotonic solution (sterile water) may cause the intracellular fluid volume to increase by as much as 60-70%.

2.    Red cells immediately swell  to a spherical shape instead of their normal biconcave disc.

3.    Intracellular tension rises and the cell membrane becomes more permeable.

4.    Cellular constituents begin to leak into the surrounding hypotonic solution until an osmotic equilibrium is attained.

5.    The red cell may return to its normal shape when resuspended in an isotonic environment, but the intracellular constituents are markedly different.

6.    Plasma free hemoglobin in the form of acid hematin circulates in the blood and may precipitate in the distal tubules of the kidneys, causing mechanical blockage which may lead to renal failure.

7.    In order to decrease precipitation, high urine output and elevated urine pH must be maintained.

8.    Plasma free hemoglobin spillage concentrations may appear as follows:

a.    2 mg/dL is a very faint pink
b.    100 mg/dL, the plasma would appear quite red
c.    150 mg/dL, hemoglobinuria occurs as hemoglobin is filtered into the urine.

II.       Treatment

1.    Stop transfusion immediately.

2.    Treat hypotension:

• Crystalloid
• Dopamine (also to increase renal perfusion).
• Other blood if needed.

3.    Maintain adequate urine output (75-100 ml/hr. or 1-2 ml/Kg/hr)

• Mannitol 12.5 – 50 gm. over 5-15 minutes IV
• Iv fluids to maintain hydration
• Furosemide 20-40 mg IV
• Albumin (250 ml-5% or 50 ml-25%) as plasma volume expander

4.    Increase urine pH to 8

• Sodium bicarbonate 40-70 mEq/70 Kg and repeat urine pH every two hours.

5.    Monitor patient plasma and urine hemoglobin concentrations as well as fibrinogen, fibrin split products, platelet count, activated partial thromboplastin time, and serum haptoglobin if DIC is suspected.