Specimen

Plasma

Collection Medium:

Alternate
Collection Media:

Light Green top tube (Lithium Heparin)

Minimum:

Adult preferred minimum: 4 mL plasma
Adult absolute minimum: 2.5 mL plasma
Pediatric minimum: 1.5 mL plasma
Patient must be calm and supine for 30 minutes pre-collection.

Delivery Instructions:

Mix well and place on wet ice.  Keep on ice and deliver to
laboratory immediately.

Specimen
Instructions:

With patient supine for 30 minutes, collect blood into heparinized
tube.  Indicate on requisition if patient is supine or upright.  Plasma 
must be separated from cells as soon as possible, within one hour of 
collection.

Analytic Time:

1 week

Reference Range:

Epinephrine
2-10 days          36-400 pg/mL
11 days-3 months   55-200 pg/mL
4-11 months        55-440 pg/mL
12-23 months       36-640 pg/mL
24-35 months       18-440 pg/mL
3-17 years         18-460 pg/mL
18 years and older 10-200 pg/mL

Norepinephrine
2-10 days           170-1180 pg/m
11 days-3 months    370-2080 pg/m
4-11 months         270-1120 pg/mL
12-23 months        68-1810 pg/mL
24-35 months        170-1470 pg/mL
3-17 years          85-1250 pg/m
18 years and older  80-520 pg/mL

Dopamine
2 days and older:   0-20 pg/mL

Interpretive Data:

Small increases in catecholamines (less than 2 times the upper 
reference limit) are usually the result of physiological stimuli, 
drugs, or improper specimen collection. Significant elevation of one or 
more catecholamines (2 or more times the upper reference limit) is 
associated with an increased probability of a neuroendocrine tumor. 
Measurement of plasma or urine fractionated metanephrines provides 
better diagnostic sensitivity than measurement of catecholamines.

Comments:

Medications which may interfere with catecholamines and
metabolites include amphetamines and amphetamine-like compounds,
appetite suppressants, bromocriptine, buspirone, caffeine,
carbidopa-levodopa (Sinemet), clonidine, dexamethasone,
diuretics (in doses sufficient to deplete sodium), ethanol,
isoproterenol, methyldopa (Aldomet), MAO inhibitors, nicotine,
nose drops, propafenone (Rythmol), reserpine, theophylline,
tricyclics and vasodilators.  The effects of drugs on
catecholamine results may not be predictable.

Test
Limitations:

Children, particularly those under two years of age, often show an 
elevated catecholamine response to stress.

Methodology:

High Performance Liquid Chromatography

CPT Code:

82384

See Additional Information:
Specimens Requiring Immediate Delivery