Demonstrating the Effects of Pre-Analytical Errors

Expires May 18, 2019


Length: 52 minutes


One of the pre-analytic errors that can most profoundly influence chemical testing is specimen contamination. In this session, audience members will observe blood gas and electrolyte testing on native specimens. The audience will then be asked to predict the impact of deliberate contamination of blood gas specimens with air, or serum specimens with a solution used for total parenteral nutrition.


Upon completion of this activity, participants should be able to:

  • Define major pre-analytical errors leading to specimen contamination for blood gas and chemical testing.
  • List chemical analytes most likely to be impacted by specimen contamination.
  • Predict the impact of air bubbles and total parental nutrition (TPN) contamination on blood gas and electrolyte testing.

Intended Audience

This program is appropriate for clinicians, pathologists, medical technologists, nurses, pharmacists, and other allied health staff.

Level of Instruction



Brad Karon, MD, PhD
Associate Professor of Laboratory Medicine and Pathology
Consultant, Division of Clinical Core Laboratory Services
Department of Laboratory Medicine and Pathology
Mayo Clinic College
Rochester, Minnesota



The following types of credit are offered for our Virtual Lecture programs:

State of California
State of Florida

To obtain credit:

  1. Watch the video.
  2. Complete the posttest and evaluation that launches immediately following the video.
  3. Generate and print your certificate.

For an instruction sheet that describes the process, see

Note: Participants requesting P.A.C.E.® credit, in compliance with ASCLS P.A.C.E. program requirements, must attain a score of 70% or higher on the posttest to obtain a certificate.

Mayo Medical Laboratories is approved as a provider of continuing education programs in the Clinical Laboratory Sciences by the ASCLS P.A.C.E.® program. This program has been approved for a maximum of 1.0 P.A.C.E® contact hour.

Mayo Medical Laboratories is approved as a Continuing Education Accrediting Agency for Clinical Laboratory Science for State of California and State of Florida credit. Florida Board of Clinical Laboratory Personnel has designated this program for General credit. The level of instruction for this program is intermediate. This program has been approved for 1.0 contact hour.


MML Education

This post was developed by our Education and Technical Publications Team.