Transfusion medicine

During big procedures like open heart surgery, patients need anticoagulants to prevent dangerous blood clot formation and regular bedside monitoring to make sure the drugs aren’t also causing problems like excessive bleeding. Investigators comparing some common bedside testing platforms to quickly determine how fast blood is clotting, called activated clotting time, or ACT; suggest other providers also compare results among the systems out there and use a more lengthy laboratory-based measure to confirm what they find.

More lengthy laboratory

“It’s like walking on a knife’s edge,” Dr. Thomas Z. Thompson; a third-year pathology resident at the Medical College of Georgia and AU Health. “You have to really get it within a certain range;” he says of the delicate balance of keeping the viscosity of the blood just right so it does not form clots that go to the lungs or brain and; conversely, does not result in bleeding.

Their perusal, published in the journal Laboratory Medicine; determined the iS TAT platform, which enables not just a bedside determination of ACT within a few minutes but can also provide results on a wide variety of other internal measures like sodium levels in the blood; a better overall option for streamlining patient care and proficiency testing.

Commonly used anticoagulant

Fast-acting heparin is the commonly used anticoagulant and ACT; the most commonly used measure to keep tabs on clotting time during treatments like cardiothoracic surgery and percutaneous; or through the skin, procedures to insert a stent to improve blood flow in the heart.

That way, caregivers know how much heparin is inhibiting the ability to clot so they can make adjustments, for example, if the operation is wrapping up. This “point of care” approach also has been shown to decrease the need for blood transfusions later; although it is generally more costly than tests done in the lab.

Point of care ACT measures are typically used in more critical situations where results need to be as close to real time as possible, Thompson says. Critical situations include procedures like ECMO; or extracorporeal membrane oxygenation; which is generally performed as a lifesaving measure for babies; requires a lot of manipulation of the blood; including removing it from the body, putting it through a machine which adds oxygen and then back into the baby; Thompson says.

Common surgeries perform

“If you have a concern post-surgery for a knee or hip replacement, there is a baseline anticoagulation we want to keep you at;” says Thompson. “But for big procedures like these; we anticoagulate patients to a much higher extent because we are taking blood typically right out of the patient; running it through a machine and giving it back to them.
Artificial travel is much more a coagulant than the blood just passing through our bodies;” he says of procedures like ECMO and coronary bypass surgery; one of the most common surgeries performed in the United States. “That is where we come in because we have the test that tells the surgeon you can start the surgery and we also have the test that says now you can reverse the heparin you have given the patient; so that they are now back to baseline when you finish the surgery;” Thompson says.