As many people will tell you, ideas and philosophies in medicine often go through swings. Things will be in style for years, and then slowly the tide turns, and that same idea or philosophy is seen as archaic or wrong, only to come back again years later. We are currently at an ebb when it comes to physiology in medicine and we are the worse for it. If there was ever a time in medicine for physiology to come back to medicine, it is now. Our knowledge of medicine and our ability to treat patients is exponentially more advanced than it was 40 years ago. The shear information to be retained is impossible, a foundation in physiology helps bridge this shortcoming and provides the optimal management of patients.
The father of experimental physiology is of some debate. The earliest physiologist to receive that title was William Harvey who was born in 1578. He described the circulatory system in the human body and did experiments to back it up. Another physicist given the title was Albrecht von Haller, a Swiss biologist born in 1708 who discovered muscle and nerve stimulation. Fast forward over 100 years to the late 1800s and there is mention of Sir Michael Foster, Professor of Physiology at Cambridge, and Claude Bernard, a French physiologist, who advanced the field of modern experimental physiology and started bridging the gap between physiology and clinical medicine (1-3).
Physiology emerged in North America in 1822 when Dr. William Beaumont studied the gastric secretions of Alexis St. Martin, a fur trapper who sustained a gunshot wound complicated by a gastroenteric fistula (4).
In 1932 Sir Henry Dale spoke at the 100-year anniversary of the British Medical Association and shared his experiences with physiology in medicine and his vision of the future. While he firmly thought that physiology and biochemistry should have their independence to be able to follow ideas and thoughts not constrained by their clinical applicability, he also believed that medicine and physiology would only progress working together. Dale stated, “The real danger, I believe, lies rather in the very success which has appeared for a time to come from this division of function, and the resulting tendency for medicine and surgery to regard experimental research as the function of physiology and pathology, and the acceptance and application of its results as the function of medicine and surgery”. Meaning that the contributions and advancements in experimental physiology are often not given the credit they deserve and instead the credit often goes to the broader fields of medicine or surgery, which limits the scope of a clinician’s ability to understand the patient (1,5).
Deterring from understanding the path to medical knowledge, leads students to have to memorize facts to be successful. Dale stated “Several powerful warnings have recently been uttered against the growing danger to the student, in the mass of facts which he must endeavor to swallow and hold ready for disgorgement in the examination room. Even if such " fact-cramming" were educationally good, practical considerations must set a limit to the time available and thus to the total volume” (1,5).
He even postulated that in the future we would see this problem and medical schools would try to place students into the clinical area sooner and teach less to be able to allow more time for memorizing these facts instead of understanding the concepts. He described this solution as desperate and worrisome. “There is abundant justification, however, for the plea that the real object of the medical curriculum should be to train the student to observe, to think, and to form a reasoned judgment, and not to make confused and evanescent records on his memory”. As long as students train in the broad methods and aims of physiology, they will acquire the skills necessary to acquire and understand the etiology, diagnosis, and treatments needed (1,5).
“Physiology, investigating the phenomena of life itself, must always remain the central core of the knowledge required by medicine”. Exposing students early to physiology creates a foundation for facing problems, that their ability to interpret physical, anatomical, and chemical data acquired from being presented unknown complexities for the first time allows them to make sound decisions (1,5).
“We have surely moved far from the position in which, as a student entering the wards some thirty-two years ago, I was told that my first duty was to forget physiology, which had no relation to medicine” (1).
It seems that, for a time, physiology and medicine remained tightly connected and the amount of knowledge attained and treatments discovered from the 1930s to 1980s was astounding. However, in the 1980s, two changes occurred that forever changed medicine: its approach and its teaching methods in medical school. In 1985, Feinstein and Sackett each published an article laying out how to take epidemiological data presented in randomized controlled trials and the resultant meta-analyses and systematic reviews and use them to make optimal medical decisions. This was done to transition away from the clinical judgment which was felt not to be standardized enough and it brought the birth of Evidence-Based Medicine (EBM) (6).
Sackett would tell the story of George Washington’s death. Washington came down with epiglottitis and the physicians and experts were called to care for him. While tracheostomy was a known treatment for epiglottis, the experts agreed that blood-letting would be the best treatment. George Washington died from iatrogenic exsanguination surrounded by “experts” (7).
And while it seemed that Sackett had contempt for physiology and clinical expertise, he was aware that EBM was dangerous without it. “Good doctors use both individual clinical expertise and the best available external evidence, and neither alone is enough. Without clinical expertise, practice risks becoming tyrannized by evidence. Evidence-based medicine is not “cookbook” medicine” (8)
The idea of EBM being the solution to practice deviations snowballed into the medical practice we have today; where it is more important to follow a paper than treat the patient in front of them. Physicians are graded on how well they follow a guideline instead of how well they treat their patients.
Dr. Gattinoni, professor of anesthesiology and critical care medicine, is a giant in the field of critical care and published over 200 research articles and reviews. He writes about this change, where randomized controlled trials became the gold standard for assigning value to an intervention. Physicians became trialists and research specialists and these physicians became the final word of what was considered a good trial and to which patients it could be generalized (6).
The second change was in 1989, when the gene variant for the most common form of cystic fibrosis was identified, which brought about the idea of molecular biology and genetics. Researchers felt they could discover the gene variants to common diseases like hypertension and diabetes and use this intervention earlier on these patients, and prevent and treat diseases at the gene level. Physiology took a back seat, and was even abandoned, as the race to sequence the human genome and identify the genetics of disease became a primary focus (4).
“Physiology [is] dying, it [is] being smothered by reductionist hype vs. being killed by objective data. Coursework in a medical school devoted to physiology declined at many institutions,
and reductionist disciplines such as molecular biology and genetics were thought to offer the next wave of solutions to clinical problems. A number of high-profile physiology departments either “went out of business” or changed their names to reflect this reality” (4).
Another notable expert in the field of critical care, Dr. Martin Tobin, has also expressed the importance of physiology in the practice of medicine. He believes that physicians acquire two types of knowledge, formal and experiential. Formal knowledge is gained from reading, lectures, etc., and experimental knowledge is gained from clinical experience. Formal knowledge sets the foundation on which experimental knowledge is built. This foundation should be built on physiology and pathophysiology.
“Fresh thinking that breaks free from circular reasoning and cliches is vital. Each patient is unique: not the next specimen on a conveyor belt awaiting treatment by protocol” (9).
Almost a century later, later we are right back where we started, with the idea that people do not need physiology to be a part of medicine and experts in the field hoping to have it return. Gattinoni and Tobin have both written articles hoping to bring back a focus on physiology. It was Tobin who wrote: “Trainees of the 2010s possess a fraction of the pathophysiology known by residents of the 1980s” (9)
It was spring 2020, after finishing some bedside teaching on hemodynamics to a critical care fellow. The fellow thanked me and said “This makes so much more sense. My program director told me not to worry about all this stuff, that it was not important.” Fellows are being taught to abandon the foundations that medicine was built on and, instead, being told to memorize the guidelines due to the misguided teaching that EBM is all that can be trusted.
It is not a leap to see the problems that arose from this idea. When physicians are not taught to critically think or understand physiology and pathophysiology, then solutions to clinical problems are a mere conditional construct that is no better than simple computer code. Disease management and treatment become a series of If-Then statements that make deviations from conditional statements impossible and limit the ability of the physician.
Evidence-based medicine, as we currently practice, has been reduced to if a patient presents with A then do B. This method is not reliable. For example, when a patient presents with AZ, the physician is not prepared and is unable to comfortably treat the patient. The patient population getting older and more obese, and deviations from a simple “if A then B” is getting more common and we can only expect more troubles for this new type of physician.
It was in 2019 that Jackson Salvant famously wrote the article, “The powerful phrase that’s ruining medicine”. In this article, he talked about how the phrase “I am not comfortable” has taken over the medical community. He brings up a lot of strong points about physicians worried about litigation and using the phrase to absolve themselves of potential legal issues in the future. He also talks about physicians leaving high-stress practices and working less and by saying they are uncomfortable; these high acuity patients will be pawned off on the next physician in line (10). While I do think that these are accurate and are things that I see every day, I also would like to bring into the mix that this is a consequence of the “modern physician”. The physician who encounters a patient then looks to the guidelines and plugs in the answer. This is the new age of medical practice.
For example, patient 1 has diabetes, give drug A. Is glucose still too high? Add drug B and they should get better. Patient 2 has hypertension, give drug C and they should get better. Patient 3 has a cough and infiltrates on x-ray, activate sepsis bundle and they should get better. But then, Patient 4 presents to the hospital. Patient 4 has a history of hypertension, diabetes, and coronary artery disease and is now hypotensive, tachycardic, and bilateral infiltrates on the x-ray. The sepsis bundle was activated and they received the guideline-directed fluid and antibiotics. Now the patient is worse, on 100% oxygen, tachypneic, with worsening lactate. There is not a guideline for post guideline care, the process breaks down, and they must pass off the patient or consult someone to tell them the next If-Then. When “If-Then” fails, the modern physician has nothing to fall back on, nothing to bring forward in the back of their mind to help. So of course they are uncomfortable. They have been programmed to follow a small set of guidelines, the “practice of medicine” was abandoned 30 years ago and we are left with the pieces. This is one example, but there are endless variations.
When Sackett wrote about using evidence-based medicine to help physicians practice better medicine, it is unlikely that he envisioned a world where physicians are graded and paid based on their adherence to the surviving sepsis guidelines. Guidelines that, if not followed, can lead to the physician being written up or fired. Guidelines where, of the first 7 recommendations listed, only one meets the criteria of moderate quality of evidence or better.
2016 Surviving Sepsis Guidelines:
When Sackett created this new world, it was to prevent the mistakes of the past where Washington died at the hand of “experts”. Yet, 3 of the 7 recommendations are low quality, and another 3 of 7 are labeled BPS or “best practice statements” given by experts in the field. We are now held hostage in a world that does not meet the ideas set out by Sackett, abandon the foundation of medicine, and deviation leads to physicians losing their jobs.
It is critical that we listen to the great minds of the field today and bring physiology back to medicine. This does not mean we have to abandon evidence-based medicine. It means that by spending more time on the understanding of the human body and developing a strong background, evidence-based medicine will flourish as a tool and not as a practice.
While I am early in my career, I have had mentors along the way that have helped me understand the importance of physiology, pathophysiology, and trying to understand the unique patient in front of me. I am not sure that I am in a position to change the current path of medical school teaching and resident education. I can only hope to bring more awareness and share the knowledge and experiences of current and past experts and help advocate for this critical shift in medical education.
Martin Tobin:
“The promise that grading of articles would improve patient care, an epistemological strategy that had been demolished by far brighter brains more than 40 years before. Randomized controlled trials are invaluable in evaluating drugs and other therapies, but provide zero help with the principal impediment in all clinical encounters: perceiving the right diagnosis concealed beneath confounding camouflage. Creative thinking depends on neurons nourished by scientific understanding, not on the grading of articles. From the nineteenth century onward, the epoch of Virchow, Bernard, and Starling, the practice of medicine had been grounded on physiologic principles. To barter science for sophistry is an exchange that even Faust would not have contemplated” (9).
Luciano Gattenoni:
“As currently practiced, evidence-based medicine relies on randomized controlled trials, from which reviews and meta-analyses primarily derive. It is evident that if the premises of the trials are incomplete, wrong, or too vague, the results of the trial will be negative. It is impressive to see the disproportion between the attention paid to the design of a trial compared with that
spent analyzing the validity of the premises and the derived hypotheses. Physiology helps to design premises and theories; without strong premises and theories, whatever the trial will prove is, in the best case, useless or, if misinterpreted, dangerous” (6).
Michael Joyner:
“Physicians who had a solid understanding of physiology and were intellectually ready to integrate new ideas into their own pathophysiological conceptual models contributed to progress. If therapeutic progress for complicated diseases is to continue, perhaps the solution is more and not less physiology and more training of future physicians. To many, the idea that more, not less, physiology education and training is needed will seem counter-intuitive, but many physiological questions and approaches in medicine seemed counter-intuitive until the answer appeared” (4).
References:
1. Dale H. An address on the relation of physiology to medicine, in research and education. Br Med J. 1932;2(3753):1043-1046. doi:10.1136/bmj.2.3753.1043
2. Father of Physiology | Science | AAAS. Accessed July 6, 2020. https://www.sciencemag.org/news/1999/10/father-physiology
3. William Harvey | Biography, Education, Experiments, Discoveries, & Facts | Britannica. Accessed July 6, 2020. https://www.britannica.com/biography/William-Harvey
4. Joyner MJ. Why Physiology Matters in Medicine. Physiology. 2011;26(2):72-75. doi:10.1152/physiol.00003.2011
5. Walsh K. “I was told that my first duty was to forget physiology, which had no relation to medicine.” Advances in Physiology Education. 2016;40(2):145-146. doi:10.1152/advan.00192.2015
6. Gattinoni L, Carlesso E, Santini A. Physiology versus evidence-based guidance for critical care practice. Crit Care. 2015;19(S3):S7. doi:10.1186/cc14725
7. Thoma A, Eaves FF. A Brief History of Evidence-Based Medicine (EBM) and the Contributions of Dr David Sackett. Aesthet Surg J. 2015;35(8):NP261-NP263. doi:10.1093/asj/sjv130
8. Singer M. Sepsis: personalization v protocolization? Crit Care. 2019;23(S1):127. doi:10.1186/s13054-019-2398-5
9. Tobin MJ. Why Physiology Is Critical to the Practice of Medicine. Clinics in Chest Medicine. 2019;40(2):243-257. doi:10.1016/j.ccm.2019.02.012
10. Salvant J. The powerful phrase that’s ruining medicine. KevinMD.com. Published April 20, 2019. Accessed July 6, 2020. https://www.kevinmd.com/blog/2019/04/the-powerful-phrase-thats-ruining-medicine.html