Mary Lou Turgeon, EdD, MLS (ASCP) of Mary L. Turgeon and Associates, posted this question about altitude and blood collection on CLSEduc, the Clinical Laboratory Science educators’ bulletin board on September 1:
How do those of you living in the Mile High City or other high altitudes deal with the effect of altitude on the blood draw into evacuated tubes? Dr. Turgeon (whose name is familiar as the author of Clinical Hematology, Theory and Procedures, 4th Edition, Lippincott, Williams and Wilkins, Philadelphia, 2005) found this statement in the 2009 BD Lab Notes: “In situations where blood is drawn at high altitudes ( over 5,000 feet), the draw volume may potentially be affected. Because the ambient pressure is lower than at sea level, the pressure of the residual gas inside the tube will reach this reduced ambient pressure during filling earlier than if the tube were drawn at sea level. Hence, the draw volume will be correspondingly lower.”
Turgeon goes on to comment “However, they do not state how to remediate this, if it is a problem. I am interested in what happens in real life high altitudes. I’m assuming that they aren’t concerned about drawing protimes on Mt. Everest or in outer space. But this could be an issue for climbers on Coumadin!”
In responses she received from two well-known educators in Denver and Las Vegas, it seems that there is no problem with draw volumes at higher altitudes. I am posting this here to learn if any others have had to make an adjustment.
Educators like me in resource-poor university programs have for years accepted contributions of outdated tubes for venipuncture practice, and both respondents commented that whereas in the past when we were using glass tubes, the outdated ones performed just fine, the new plastic tubes tend to lose vacuum soon after outdating, creating a new challenge.