This section will explain to you about discard tubes, its criteria and situations that are appropriate for discard tubes to be used.

What Are Discard Tubes and Its Criteria?

Discard tubes are extra waste tubes used as a discard tube before proceeding with specimen draw. The criteria of discard tubes are:

They do not contain any additives.

Evacuated and sterile on the inside.

Why in certain situations, discard tube usage is important?

Trauma induced via venipuncture releases tissue thromboplastin which contaminates tube sample, causing shorter clotting time, reducing the accuracy of coagulation testing.

Ensures maintenance of the proper anticoagulant:blood ratio in the first tube filled.

When using butterfly needle, the use of discard tube is important to displace any air in the tubing of the needle prior to filling other tubes, preventing underfilling of tubes.

Avoid cross contamination of additives from previous tubes to other tubes.