Chapter Six: My Lab Tests and Scans

Brian Byrd is a physician-scientist & cardiologist at the University of Michigan, where he runs a research lab. At one point, Dr. Topol was also member of the U-M faculty, and his career trajectory is inspiring. Dr. Topol pushes the boundaries of what a physician-scientist can do to impact health care, and he sets an example for the rest of us in the process.

Reminder/disclosure: my laboratory is funded by the National Institutes of Health to research a new approach to laboratory testing related to high blood pressure.

In Chapter 6 of #PWSYN, Dr. Topol presents a vision of how we’ll diagnose diseases in the future.

Laboratory Tests

Dr. Topol predicts a transition from tests that require tubes of blood for analysis in resource-intensive laboratory facilities to tests that are more convenient for the patient. He begins with a discussion of Theranos, a company that has specialized in drawing small amounts of blood, rather than tubes. Since #PWSYN was written, Theranos has become famous for all of the wrong reasons. See this and this.

Dr. Topol’s experience during a visit to Theranos was impressive enough to make one wonder whether there could be hope for their approach. His testing was painless, with extraordinarily rapid results. But, the passage of time has shed new light on Theranos and their testing. Dr. Topol has already shared a preview of an updated edition of #PWSYN addressing this topic, and his outlook has changed, as you can see:

The next contender that might change laboratory testing: the lab-on-a-chip. It is increasingly feasible to perform lab tests on microfluidics platforms that interface with smartphones. Dr. Topol provides a nice overview of the state of the art, which continues to evolve. Handheld analyzers have been common in some clinical settings for a while. For example, a small handheld device can be used to measure the effect of a blood-thinner in the cardiac catheterization laboratory. Emergency room clinicians can check for evidence of injury to the heart, blood sugar, and other “lab” tests using a hand-held blood analyzer, too. Expect laboratory testing platforms to become ever smaller & more portable. A key question in my mind is how to account for quality control with tests performed outside specialized laboratories. It’s easy to identify good experiences with outside-the-lab testing--like the cath lab & ER testing described above--and bad experiences. Ultimately, we may end up with tests that are not quite as robust as what we use now. But these new platforms will be valuable nonetheless. For example, they might provide essential blood tests to patients in parts of the world that lack big, exquisitely temperature- and humidity-controlled clinical laboratories typical in US hospitals since the 1960’s. This old model is neither scalable nor agile, and new testing platforms may make them irrelevant, particularly in more resource-constrained regions.

Dr. Topol next introduces the concept of the lab-in-the-body. Continuous blood glucose monitors are now commonly used by patients with diabetes and could be seen as an early implementation of lab-in-the-body. But Dr. Topol sees a future in which some monitoring devices may reside in the blood stream, rather than having a sensor in the skin. I can think of some concerns: a device in the blood stream could embolize--travel to the smallest part of an artery, blocking blood flow--or promote clots or infection. But a clever approach might tackle these problems – or avoid them altogether. Perhaps this is part of what has made this book such a hit: it’s endlessly interesting to think about what might be possible!

Imaging Tests

Dr. Topol gives a perspicacious overview of the landscape of imaging tests. Though much of Chapter 6 focuses on what might be relevant in the future, Dr. Topol hones in on a very pragmatic topic that should affect patients’ decisions now. He provides a thoughtful discussion of the possibility that screening imaging tests are doing more harm than good in some contexts. He includes in the discussion some estimated radiation exposures for different types of tests. However, he also points out that for a given test, radiation doses vary depending upon who is doing the test. I couldn’t agree more with his call for complete transparency around that issue. Let’s assume for a moment that there are good reasons some providers use more radiation than others (I’m not saying this is so—I don’t know). Why shouldn’t those providers explain the reasons to well-informed patients--and their referring providers, who should also be interested?

As with laboratory testing, Dr. Topol identifies a trend toward miniature, convenient imaging devices. He has “not used a stethoscope to listen to the heart of a patient in years” since he can now see the heart and its valves using handheld ultrasound. He argues that use of handheld ultrasound might reduce the $100 billion in ultrasound-related costs to the US healthcare system by half. Currently, the US healthcare system relies heavily on technologists trained to perform ultrasound, leaving many clinicians relatively or completely unpracticed in this area. As a cardiologist, I am not yet seeing much adoption of handheld ultrasound in place of the stethoscope: I’ve met one only cardiologist who uses handheld ultrasound routinely, but in addition to the stethoscope. But it’s early days yet, and Dr. Topol points out that training programs for physicians are beginning to embrace handheld ultrasound. Handheld ultrasound of the heart and other organs could very well replace the stethoscope! Dr. Topol also makes a strong & eye-opening case for patients directly obtaining their images (not the report—the pictures), even if they can’t interpret the pictures. For example, when patients have their images, second opinions become simpler to obtain, and duplicate imaging is less likely to be ordered unnecessarily by a clinician who doesn’t have prior images.

Dr. Topol concludes the chapter by highlighting the amazing potential of the smartphone to change the current approach to the physical examination. For example, it’s possible to see the eardrum using a smartphone with an attachment. It’s also possible to transform a smartphone into a powerful microscope.

Marshall McLuhan made no distinction between artists and scientists. An artist, he said, was a person “in any field, scientific or humanistic, who grasps the implications of his actions and of new knowledge in his own time.” That definition resonates with me as I read Dr. Topol’s work. How many of us can step outside the frame of immediate events and see ourselves, others, and technology in broad context? We’re lucky to have Dr. Topol, who possesses that rare skill, and is willing to share!