Specimen:

Plasma

Collection Medium:

Alternate
Collection Media:

Call laboratory for additional acceptable specimen collection 
containers.

Minimum:

5 ml; light green top tube or one 0.6 ml microtube.

Testing
Schedule:

24 hrs/day, 7 days a week, including holidays.

Analytic Time:

2 hours (upon receipt in laboratory)

Reference Range:

The parent drug, procainamide (PA) and n-acetyl metabolite are 
quantitated separately.  N-acetyl procainamide (NAPA) will not be done 
unless specifically requested.  NAPA is most useful in renal failure.

Therapeutic range for procainamide is 4-10 mcg/mL with toxicity 
beginning at levels greater than 16 mcg/ml.

Test
Limitations:

Icterus: No significant interference up to an I index of 60 
(approximate bilirubin concentration: 60 mg/dl).

Hemolysis: No significant interference up to an H index of 1000 
(approximate hemoglobin concentration: 1000 mg/dl).

Lipemia (Intralipid): No significant interference from lipemia up to an 
L index of 1000. (approximate triglycerides concentration: 2000 mg/dl).

No significant interference from total protein up to 13 g/dl.

No significant interference from rheumatoid factors up to 66 IU/ml.

As with any assay employing mouse antibodies, the possibility exists 
for interference by human anti-mouse antibodies (HAMA) in the sample, 
which could cause falsely elevated results.

The incidence of patients with antibodies to E. coli beta-galactosidase 
is extremely low. However, some samples containing such antibodies can 
result in artificially high procainamide results that do not fit the 
clinical profile.

Methodology:

Photometric Assay

Sample
Processing:

Centrifuge at 3000 RPM for 10 minutes.
Aliquot plasma into labeled container and cap.

Sample
Storage:

Refrigerate.

Transport
Instructions:

Place specimen into zip-lock type bag, seal bag.
Place requisition into outside pocket of bag.
Transport in cooler with refrigerated coolant packs.

CPT Code:

80190

See Additional Information:
Chemistry Critical Lab Values