Tag Archives: blood

New technology

New Technology: Blood Type In 30 Seconds!

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This one is really exciting! Blood banks typically keep a significant number of units of O- “universal donor” blood available. These units can be given immediately when a trauma patient in need arrives, since it contains no antigens to the common blood types. It takes anywhere from 5-15 minutes for the blood bank to determine the blood type from the patient’s blood. Then and only then can they begin delivering “type specific” blood that matches the patient’s blood type.

Researchers at the Third Military Medical University in China have developed a paper-based test to determine the ABO type as well as the Rh type (D). Indicators for A, B, and D antigens turn a blue color when they are present, allowing the clinician or blood bank to accurately determine the blood type in 30 seconds. 

Why is this important? O- is an uncommon blood type, with only about 6% of the US population carrying it. Yet blood banks have to keep an inordinate amount in stock “just in case.” Using a blood type test like this could significantly cut down on unnecessary use of this rare O- blood. Unfortunately, it will be 1-2 years before the test is commercially available. I’m sure our nation’s blood bankers can’t wait!

Here’s a brief video that demonstrates how it works.

YouTube player

Reference: A dye-assisted paper-based point-of-care assay for fast and reliable blood grouping. Science Translational Medicine 15 Mar 2017:
Vol. 9, Issue 381, eaaf9209.

General

Lab Values From Intraosseous Blood

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The intraosseous access device (IO) has been a lifesaver by providing vascular access in patients who are difficult IV sticks. In some cases, it is even difficult to draw blood in these patients by a direct venipuncture. So is it okay to send IO blood to the lab for analysis during a trauma resuscitation?

A study using 10 volunteers was published last year (imagine volunteering to have an IO needle placed)! All IO devices were inserted in the proximal humerus. Here is a summary of the results comparing IO and IV blood:

  • Hemoglobin / hematocrit – good correlation
  • White blood cell count – no correlation
  • Platelet count – no correlation
  • Sodium – no correlation but within 5% of IV value
  • Potassium – no correlation
  • Choloride – good correlation
  • Serum CO2 – no correlation
  • Calcium – no correlation but within 10% of IV value
  • Glucose – good correlation
  • BUN / Creatinine – good correlation

Bottom line: Intraosseous blood can be used if blood from arterial or venous puncture is not available. Discarding the first 2cc of marrow aspirated improves the accuracy of the lab results obtained. The important tests (hemoglobin/hematocrit, glucose) are reasonably accurate, as are Na, Cl, BUN, and creatinine. The use of IO blood for type and cross is not yet widely accepted by blood banks, but can be used until other blood is available.

Related post:

Reference: A new study of intraosseous blood for laboratory analysis. Arch Path Lab Med 134(9):1253-1260, 2010.

General

Lab Values From Intraosseous Blood

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The intraosseous access device (IO) has been a lifesaver by providing vascular access in patients who are difficult IV sticks. In some cases, it is even difficult to draw blood in these patients by a direct venipuncture. So is it okay to send IO blood to the lab for analysis during a trauma resuscitation?

A study using 10 volunteers was published last year (imagine volunteering to have an IO needle placed)! All IO devices were inserted in the proximal humerus. Here is a summary of the results comparing IO and IV blood:

  • Hemoglobin / hematocrit – good correlation
  • White blood cell count – no correlation
  • Platelet count – no correlation
  • Sodium – no correlation but within 5% of IV value
  • Potassium – no correlation
  • Choloride – good correlation
  • Serum CO2 – no correlation
  • Calcium – no correlation but within 10% of IV value
  • Glucose – good correlation
  • BUN / Creatinine – good correlation

Bottom line: Intraosseous blood can be used if blood from arterial or venous puncture is not available. Discarding the first 2cc of marrow aspirated improves the accuracy of the lab results obtained. The important tests (hemoglobin/hematocrit, glucose) are reasonably accurate, as are Na, Cl, BUN, and creatinine. The use of IO blood for type and cross is not yet widely accepted by blood banks, but can be used until other blood is available.

Related post:

Reference: A new study of intraosseous blood for laboratory analysis. Arch Path Lab Med 134(9):1253-1260, 2010.

General

Giving Rhogam (Rh Immunoglobulin) To A Man?

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Rhogam is for women, right? The ATLS course points out that pregnant women who are Rh- and sustain significant blunt torso trauma should empirically receive Rhogam in case the fetus turns out to be Rh+.

But there is one situation where men might receive it. Most trauma centers use O- blood as their universal donor units because it does not contain any major antigens. However, O- blood is uncommon. Worldwide, only 4-9% of the population have this blood type. In China, the incidence of O- blood is nearly zero! So busy centers that don’t have much O- may substitute O+ blood for men. They then switch to the proper blood type when the crossmatch is complete

This makes sense, since men don’t ever have to worry about a Rh+ fetus. However, since this typically occurs at very busy (read: high penetrating injury) centers, there is a significant number of repeat offenders. And if they receive it again, the antibodies to the Rh factor they developed the first time can cause a significant hemolytic reaction. So men who receive O+ blood must be typed and given Rhogam if they are Rh-.

Reference: Emergency uncrossmatched transfusion effect on blood type alloantibodies. J Trauma 72(1):48-53, 2012.

General

Lab Values From Intraosseous Blood

Leave a comment

The intraosseous access device (IO) has been a lifesaver by providing vascular access in patients who are difficult IV sticks. In some cases, it is even difficult to draw blood in these patients by a direct venipuncture. So is it okay to send IO blood to the lab for analysis during a trauma resuscitation?

A study using 10 volunteers was published last year (imagine volunteering to have an IO needle placed)! All IO devices were inserted in the proximal humerus. Here is a summary of the results comparing IO and IV blood:

  • Hemoglobin / hematocrit – good correlation
  • White blood cell count – no correlation
  • Platelet count – no correlation
  • Sodium – no correlation but within 5% of IV value
  • Potassium – no correlation
  • Choloride – good correlation
  • Serum CO2 – no correlation
  • Calcium – no correlation but within 10% of IV value
  • Glucose – good correlation
  • BUN / Creatinine – good correlation

Bottom line: Intraosseous blood can be used if blood from arterial or venous puncture is not available. Discarding the first 2cc of marrow aspirated improves the accuracy of the lab results obtained. The important tests (hemoglobin/hematocrit, glucose) are reasonably accurate, as are Na, Cl, BUN, and creatinine. The use of IO blood for type and cross is not yet widely accepted by blood banks, but can be used until other blood is available.

Related post:

Reference: A new study of intraosseous blood for laboratory analysis. Arch Path Lab Med 134(9):1253-1260, 2010.