CPK

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Blood test

Overview

Risks

Results

CPK

Definition:

A CPK is a blood test that measures creatine phosphokinase (CPK), an enzyme found predominantly in the heart, brain, and skeletal muscle. When the total CPK level is substantially elevated, it usually indicates injury or stress to one or more of these areas.

Alternative Names:
CK; Creatine kinase; Creatine phosphokinase
How the test is performed:

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Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic. An elastic band is placed around the upper arm to apply pressure and cause the vein to swell with blood.

A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the band is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

In infants or young children:

The area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. A bandage may be applied to the puncture site if there is any bleeding.

This test may be repeated over 2 or 3 days for a hospitalized patient. The pattern of a rise or fall in CPK (or CPK isoenzymes) can be diagnostically significant.

How to prepare for the test:

Usually, no special preparation is necessary.

Infants and children:

The preparation you can provide for this test depends on your child's age, previous experiences, and level of trust. For general information regarding how you can prepare your child, see the following topics:

Infant test or procedure preparation (birth to 1 year)
Toddler test or procedure preparation (1 to 3 years)
Preschooler test or procedure preparation (3 to 6 years)
Schoolage test or procedure preparation (6 to 12 years)
Adolescent test or procedure preparation (12 to 18 years)

How the test will feel:

When the needle is inserted to draw blood, you may feel moderate pain, or only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed:

When a muscle is damaged, CPK leaks into the bloodstream. Determining which isoenzyme (specific form of CPK) is elevated will help determine which tissue has been damaged.

This test may be used to:

Diagnose heart attack
Evaluate cause of chest pain
Determine the extent of muscle damage caused by drugs, trauma or immobility
Detect early dermatomyositis and polymyositis
Distinguish malignant hyperthermia from a postoperative infection
Help discover carriers of muscular dystrophy (Duchenne)

Repeated checks of CPK levels may be performed. The pattern and timing of a rise or fall in CPK levels can be diagnostically significant, particularly if a heart attack is suspected.