Specimen Requirements

A blood specimen must be collected for screening when the baby is between 24 and 48 hours old. If the specimen is collected from an infant before 24 hours of age, a second specimen must be collected no later than the 14th day of life.

Collect specimen on “Minnesota Department of Health PKU Filter Paper” as follows:
1. Do not use capillary tubes to collect blood spot specimen.

2. Sterilize heel side and perform puncture according to procedure described in Nursery’s policy “Newborn Metabolic Screening.”

3. Wipe away first drop of blood with sterile gauze.
4. Allow a large drop of blood to accumulate.
5. Gently touch filter paper against large drop of blood and in 1 step, allow a sufficient quantity of blood to soak through to completely fill circle on filter paper.

Note:  1. Apply blood only to 1 side of filter paper.

2. Avoid repeated applications of blood to filter paper to fill 1 circle. Allow circles to fill by natural flow.

3. Do not milk or squeeze puncture site, this will dilute specimen with tissue fluid.

4. Do not layer successive drops of blood in a circle (this causes caking).

5. If blood flow diminishes so that circles are not completely filled, repeat sampling technique in another circle. Do not apply blood more than once in same collection circle on filter paper.

6. Avoid touching blood collection area of filter paper prior to, during, and following sampling.
7. Completely fill all circles on filter paper.
8. Keep filter paper in the dark until it is brought to the laboratory. Forward promptly.
9. Once in the laboratory, hang “Minnesota Department of Health PKU Filter Paper” in designated area.

Note:  The fee for “Newborn Metabolic Screening, Blood Spot” is paid for in advance when “Minnesota Department of Health PKU Filter Paper” is purchased. Do not throw these slips away! Notify St. Luke’s Hospital Laboratory Client Service Department at 218-249-5200 if an error has been made on a slip.