correction forumula for HIGH PCV /HCT in coagulation tests.

Correcting high hematocrit coagulation

Packed cells up this high indicates a high hematocrit (ᡯ) the patient may need a custom draw. 

This hematocrit  is 40.5%

Use the following formula to customize a collection for a patient with a hematocrit greater than 55%

Step 1. Solve for “a” where a= 3.2 * (100-the patient’s hematocrit)/ 55 

Step 2. Solve for “y” where y = a * 0.3 / 3.2

y is the volume of 3.2% citrate needed to add

to 2.7 ml of patient’s blood.

Example: Let’s say the patient has a Hct of 63% 

Step 1. Solve for “a” where a= 3.2*(100-63)/ 55

a= 2.15

Step 2. Solve for “y” where y = 2.15 * 0.3 / 3.2

y= 0.2

You would now use 0.2ml of 3.2% citrate for

2.7 ml of patient’s blood.