Altitude and Vacuum Tubes

Altitude and Vacuum Tubes
Sep 4, 2010 4:51am

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Educators like me in resource-poor university programs have for years accepted contributions of outdated tubes for venipuncture practice, and both respondents commented that whereas in the past when we were using glass tubes, the outdated ones performed just fine, the new plastic tubes tend to lose vacuum soon after outdating, creating a new challenge.

2 Comments

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.

By Laura
Mar 19, 2021 12:33pm
Hi George,
I'm not sure if you've received any further insight on this topic since 2014. I work for a health system based in Colorado, and while none of our hospitals in the Denver metro area have an issue with the altitude (approx 5280 ft.), our mountain clinics closer to 9000 ft. use exclusively glass collection tubes for coag. (Though I am unclear how glass vs plastic affects the tube's vacuum.) I've also noticed in order to achieve PPP of <10,000 platelets, the mountain clinic is required to centrifuge for a greater amount of time compared to Denver hospitals, despite using the exact same model centrifuge and RCF. We are exploring purchasing a different model centrifuge with greater RCF capability, but I am concerned about the glass. Are you aware of maximum RCF recommendations for glass tubes?
By Director Dennis Ernst
Mar 24, 2021 11:54am
This is a very interesting discussion. The issue of drawing at high altitudes has been addressed by tube manufacturer who have created special "high altitude" tubes to prevent underfilling. I'd check with them. However, I'm unfamiliar with the phenomenon of altitude impacting the harvesting of PPP. I agree the remedy is a longer spin, not an RPM adjustment.

On the issue of glass tubes and the RCF adjustment for high altitudes, I think we need to be careful when we tinker with manufacturer's recommendations for RCF at any altitude. Excessive RCF may have other consequences, i.e., we solve one problem but create another. I hate to sound like a parrot on this, but I think the tube's manufacturer has to dictate the usage of their tubes at high altitudes. They know how their tubes perform better than anyone. If a satisfactory resolution cannot be obtained, it's rationale for switching manufacturers. Hope this helps.

Leave A Comment

You must be logged in to Comment - Sign In