By Owen Page
The progression of both science and medicine have been defined by technological advances. Calculus has lead to more complex processes, the computer enabled analysis of vast amounts of data which enabled humanity to reach the moon and be interconnected via the internet. Even now researchers everywhere are using technology to push the boundaries of scientific knowledge further than ever before. Medicine has been defined by tech as well— from the x-ray to various medical exams such as colonoscopies, from fMRI and CT scans to pacemakers and prosthetic limbs. One such interface where technology and medicine meet, studied by Jain et al, is a microfluidic device with real applications in blood hemostasis in patients.
Blood hemostasis may sound like an incredibly dull topic, but in actuality it is essential for survival. Hemostasis is the process of stopping the bleeding from an injured blood vessel. So when you cut your hand chopping veggies for dinner, one of the main reasons why you don’t bleed to death from that small cut on your finger is hemostasis. Hemostasis is governed by three processes: in order, the narrowing of blood vessels known as vasoconstriction, platelet aggregation in which platelet and collagen (a key structural protein) form a temporary plug in the injured area, and finally clot formation which is a permanent plug. Hemostasis is a process that seems rather trivial and for most people functions properly.
Now this is all good for people of normal health, but people undergoing surgery, severe trauma such as a puncture or a laceration, sepsis (essentially a body-wide infection), people on anti-coagulants (blood thinners) or undergoing anti-coagulant therapy (a common treatment to prevent stroke caused by high cholesterol), or even people that need to use dialysis machines may develop something known as coagulopathy or thrombosis.
Coagulopathy, in its most basic sense, occurs when a person is no longer able to clot effectively, which can occur due to injury. One can imagine that this poses an incredible threat to the well-being of the patient if they are undergoing surgery and cannot stop bleeding out. Certain venoms from animals such as snakes, spiders, and cone snails also can result in coagulopathy. Hemophilia is an example of a genetic disorder that results in coagulopathy. Thrombosis is the opposite condition in which there is local clotting in the circulatory system. This can lead to a stroke or pulmonary embolism, neither of which are good.
Jain et al. tested a microfluidic device from which blood clots were able to be evaluated using a mathematical model of platelet function and thrombosis formation from data gathered from in vitro blood samples. These are blood samples that are tested outside of the body. Now most blood clot assays are in vivo and are less effective at helping in real-time clinical settings. They measure clotting when there is no blood flow, yet as long as we are alive our blood will invariably flow. This change in flow is referred to as a fluid shear gradient.
This device contains very small channels that imitate narrowed arterioles followed by two more regions. The alterations create a shear gradient that accelerates positively and then negatively. The device then uses the aforementioned mathematical model to perform real-time blood clot assays and be hooked up to a device outside of the body such as a dialysis machine. Representing a new age of medicine that is highly personalized towards the individual and driven by innovative technology, this device is the kind of tech that will provide accurate real-time data that will help save lives.
References:
Jain, A., van der Meer, A. D., Papa, A.-L., Barrile, R., Lai, A., Schlechter, B. L., … Ingber, D. E. (2016). Assessment of whole blood thrombosis in a microfluidic device lined by fixed human endothelium. Biomedical Microdevices, 18, 73. http://doi.org/10.1007/s10544-016-0095-6