Category Archives: Medical Physiology

An inventory of meaningful lives of discovery

by Jessica M. Ibarra

I always had this curiosity about life. Since the very beginning, always wanting to understand how animals’ breathe, how they live, how they move. All that was living was very interesting. – Dr. Ibarra

“I always had this curiosity about life and I wanted to become a doctor, but my parent told me it was not a good idea,” Lise Bankir explained in her interview for the Living History Project of the American Physiological Society (APS).  The video interview (video length: 37.14 min.) is part of a rich collection over 100 senior members of the APS who have made outstanding contributions to the science of physiology and the profession. 

The archive gives us great insight into how these scientists chose their fields of study.  As Dr. Bankir, an accomplished renal physiologist, explain how she ended up “studying the consequences of vasopressin on the kidney.”  She describes her work in a 1984 paper realizing “high protein was deleterious for the kidney, because it induces hyperfiltration,” which of course now we accept that high protein accelerates the progression of kidney disease. Later she describes her Aha! moment, linking a high protein diet to urea concentration, while on holiday. 

“It came to my mind that this adverse effect of high protein diet was due to the fact that the kidney not only to excrete urea (which is the end product of proteins), but also to concentrate urea in the urine.  Because the plasma level of urea is already really low and the daily load of urea that humans excrete need that urea be concentrated about 100-fold (in the urine with respect to plasma).” 

Other interviews highlight how far ahead of their time other scientists were.  As is the case when it comes to being way ahead of teaching innovations and active learning in physiology with  Dr. Beverly Bishop.  In her video interview, you can take inspiration from her 50 years of teaching neurophysiology to physical therapy and dental students at SUNY in New York (video length: 1 hr. 06.09 min.).  Learn about how she met her husband, how she started her career, and her time in Scotland.  Dr. Bishop believed students could learn better with experimental laboratory activities and years ahead of YouTube, she developed a series of “Illustrated Lectures in Neurophysiology” available through APS to help faculty worldwide.

She was even way ahead of others in the field of neurophysiology.  Dr. Bishop explains, “everyone knows that they (expiratory muscles) are not very active when you are sitting around breathing quietly, and yet the minute you have to increase ventilation (for whatever reason), the abdominal muscles have to play a part to have active expiration.  So, the question I had to answer was, “How are those muscles smart enough to know enough to turn on?” Her work led to ground breaking work in neural control of the respiratory muscles, neural plasticity, jaw movements, and masticatory muscle activity.

Another interview shed light on a successful career of discovery and their implications to understanding disease, as is the case with the video interview of Dr. Judith S. Bond. She describes the discovery of meprins proteases as her most significant contribution to science (video length: 37.38 min.), “and as you know, both in terms of kidney disease and intestinal disease, we have found very specific functions of the protease.  And uh, one of the functions, in terms of the intestinal disease relates to uh inflammatory bowel disease.  One of the subunits, meprin, alpha subunit, is a candidate gene for IBD and particularly ulcerative colitis. And so that opens up a window to – that might have significance to the treatment of ulcerative colitis.”

Or perhaps you may want to know about the life and research of Dr. Bodil Schmidt-Nielsen, the first woman president of the APS (video length: 1 hr. 18.07 min.) and daughter of August and Marie Krogh.  In her interview, she describes her transition from dentistry to field work to study water balance on desert animals and how she took her family in a van to the Arizona desert and while pregnant developed a desert laboratory and measured water loss in kangaroo rats.  Dr. Schmidt-Nielsen was attracted to the early discoveries she made in desert animals, namely that these animals had specific adaptations to reduce their expenditure of water to an absolute minimum to survive. 

The Living History Project managed to secure video interviews with so many outstanding contributors to physiology including John B. West, Francois Abboud, Charles TiptonBarbara Horwitz, Lois Jane Heller, and L. Gabriel Navar to name a few.  For years to come, the archive provides the opportunity to learn from their collective wisdom, discoveries, family influences, career paths, and entries into science. 

As the 15th anniversary of the project approaches, we celebrate the life, contributions, dedication, ingenuity, and passion for science shared by this distinguished group of physiologists.  It is my hope you find inspiration, renewed interest, and feed your curiosity for science by taking the time to watch a few of these video interviews. 

Dr. Jessica M. Ibarra is an Assistant Professor of Physiology at Dell Medical School in the Department of Medical Education of The University of Texas at Austin.  She teaches physiology to first year medical students.  She earned her B.S. in Biology from the University of Texas at San Antonio.  Subsequently, she pursued her Ph.D. studies at the University of Texas Health Science Center in San Antonio where she also completed a postdoctoral fellowship.  Her research studies explored cardiac extracellular matrix remodeling and inflammatory factors involved in chronic diseases such as arthritis and diabetes.  When she is not teaching, she inspires students to be curious about science during Physiology Understanding Week in the hopes of inspiring the next generation of scientists and physicians. Dr. Ibarra is a native of San Antonio and is married to Armando Ibarra.  Together they are the proud parents of three adult children – Ryan, Brianna, and Christian Ibarra.

Medical Physiology for Undergraduate Students: A Galaxy No Longer Far, Far Away

The landscape of medical school basic science education has undergone a significant transformation in the past 15 years.  This transformation continues to grow as medical school basic science faculty are faced with the task of providing “systems based” learning of the fundamental concepts of the Big 3 P’s: Physiology, Pathology & Pharmacology, within the context of clinical medicine and case studies.  Student understanding of conceptual basic science is combined with the growing knowledge base of science that has been doubling exponentially for the past century.  Add macro and microanatomy to the mix and students entering their clinical years of medical education are now being deemed only “moderately prepared” to tackle the complexities of clinical diagnosis and treatment.  This has placed a new and daunting premium on the preparation of students for entry into medical school.  Perhaps medical education is no longer a straightforward task of 4 consecutive years of learning.  I portend that our highest quality students today, are significantly more prepared and in many ways more focused in the fundamentals of mathematics, science and logic than those of even 30 years ago.  However, we are presenting them with a near impossible task of deeply learning and integrating a volume of information that is simply far too vast for a mere 4 semesters of early medical education.

 

To deal with this academic conundrum, I recommend here that the academic community quickly begin to address this complex set of problems in a number of new and different ways.  Our educators have addressed the learning of STEM in recent times by implementing a number of “student centered” pedagogical philosophies and practices that have been proven to be far more effective in the retention of knowledge and the overall understanding of problem solving.  The K-12 revolution of problem-based and student-centered education continues to grow and now these classroom structures have become well placed on many of our college and university campuses.  There is still much to be done in expanding and perfecting student-centered learning, but we are all keenly aware that these kinds of classroom teaching methods also come with a significant price in terms of basic science courses.

 

It is my contention that we must now expand our time frame and begin preparing our future scientists and physicians with robust undergraduate preprofessional education.  Many of our universities have already embarked upon this mission by developing undergraduate physiology majors that have placed them at the forefront of this movement.  Michigan State University, the University of Arizona and the University of Oregon have well established and long standing physiology majors.  Smaller liberal arts focused colleges and universities may not invest in a full majors program, but rather offer robust curricular courses in the basic medical sciences that appropriately prepare their students for professional medical and/or veterinary education.  Other research 1 universities with strong basic medical science programs housed in biology departments of their Colleges of Arts and Sciences may be encouraged to develop discipline focused “tracks” in the basic medical sciences.  These tracks may be focused on disciplines such as physiology, pharmacology, neuroscience, medical genetics & bioinformatics and microbiology & immunology.  These latter programs will allow students to continue learning with more broad degrees of undergraduate education in the arts, humanities and social sciences while gaining an early start on advanced in depth knowledge and understanding of the fundamentals of medical bioscience.  Thus, a true undergraduate “major” in these disciplines would not be a requirement, but rather a basic offering of focused, core biomedical science courses that better prepare the future professional for the rigors of integrated organ-based medical education.

 

In the long term, it is important for leaders in undergraduate biomedical education to develop a common set of curriculum standards that provide a framework from which all institutions can determine how and when they choose to prepare their own students for their post-undergraduate education.  National guidelines for physiology programs should become the standard through which institutions can begin to prepare their students.  Core concepts in physiology are currently being developed.  We must carefully identify how student learning and understanding of basic science transcends future career development, and teach professional skills that improve future employability.  Lastly, we must develop clear and effective mechanisms to assess and evaluate programs to assure that what we believe is successful is supported by data which demonstrates specific program strengths and challenges for the future.  These kinds of challenges in biomedical education are currently being addressed in open forum discussions and meetings fostered by the newly developed Physiology Majors Interest Group (P-MIG) of the APS.  This growing group of interested physiology educators are now meeting each year to discuss, compare and share their thoughts on these and other issues related to the future success of our undergraduate physiology students.  The current year will meet June 28-29 at the University of Arizona, Tucson, AZ.  It is through these forums and discussions that we, as a discipline, will continue to grow and meet the needs and challenges of teaching physiology and other basic science disciplines of the future.

Jeffrey L. Osborn, PhD is a professor of biology at the University of Kentucky where he teaches undergraduate and graduate physiology. He currently serves as APS Education Committee chair and is a former medical physiology educator and K12 magnet school director. His research focuses on hypertension and renal function and scholarship of teaching and learning. This is his first blog.
Teaching Physiology in an Integrated Curriculum

Culmination of the 2016-17 academic year allows time for reflection and planning for the next year.   This past academic year, I was involved in the delivery of a new medical curriculum to an inaugural class of osteopathic medical students.   In keeping with current medical education trends, physiology and all other basic sciences were integrated throughout the year in individual systems based courses.  It is against this backdrop that I have decided to share a few observations and offer a few suggestions on delivering physiology content in a completely integrated teaching environment.

 

  • Delivery of an integrated curriculum is very time intensive for faculty. The idea of incorporating the teaching of anatomy, biochemistry, cell biology, physiology and microbiology/immunology of an organ system in a single course is conceptually attractive and to many medical practitioners the best way to educate the next generation of physicians.   Curricular challenges center on time limitations and the blurring of boundaries between the basic science disciplines.  Successful courses result when faculty are able to connect relevant information.   For example, my preparation for classroom discussions involved gaining an awareness of what was being taught in other disciplines and to incorporate appropriate synergies with the teaching materials developed by my colleagues in other disciplines.   The challenge was not to re-teach material.
  • Learning for the majority of students is not integrative. The development and delivery of an interdisciplinary integrated curriculum does not instantly result in students who are higher order problem solvers.   Learning is sequential, iterative, and cumulative.   Integration of concepts takes time and a firm foundation.   Guiding students along towards higher learning dimensions requires careful planning on behalf of the educator and can be accomplished through various pedagogical approaches.  Central to any approach should be basic questions for the educator to consider such as: 1) What is/are the basic fact(s) that the student should know? 2) Why does the student need to know this particular material?  and 3) How will the particular material be used in the problem solving process?   The answers to these and similar questions should then be used to introduce material in the classroom environment that keeps study groups discussing content after the session ends.
  • The true effectiveness of an integrated systems based curriculum should be measured by assessments that include questions designed specifically to high levels of integration. Data from both multidisciplinary and comprehensive formative as well as summative assessment instruments will provide a basis for future curricular decisions.

In the preceding discourse I have attempted to share a few views based on a year long teaching experience in a systems based medical curriculum.   My overall impression is that an integrated curriculum is a great way to teach physiology.   I also have learned that I am at the beginning of a new teaching journey that is sequential, iterative, and cumulative.   Sound familiar?  In preparation for next year, I know what I will be doing this summer to refine my previous year’s work in ways that facilitate student learning next year.    I am sure that I am not alone and wish you the best for a productive summer.

Joseph N. Benoit, PhD is Professor of Physiology and Director of Research & Sponsored Programs at the Burrell College of Osteopathic Medicine.   He has served in various higher education positions over the past 30 years including faculty, graduate school dean, college president and most recently founding faculty at a new medical school.   His current scholarly interests center on student learning, curriculum development, and regulatory compliance.  He lives and works in Las Cruces, NM.
Simulation as a Component of First-year Medical Physiology

cardiac simulationbIf you’ve spent any time around soon-to-retire, senior physiologists, you’ve probably heard nostalgic talk of the old dog labs.  I am a member of what may be the last generation that participated in these in a medical/graduate school environment.  The old-timers will tell you that there was no better way to teach physiology than by demonstration and experimentation with an anesthetized dog.  The experience was dramatic, and the various concepts were obviously relevant.  Nevertheless, time marches on, and with changes in economics and societal values, we are unlikely to ever see the return of the dog labs in medical or graduate school.

For the purposes of teaching physiology in a medical environment, much of the impact and value of the dog labs can be obtained through simulation.  Centers that use high-fidelity manikins and other simulation technology are becoming more and more common, and if your institution doesn’t have one yet, there is probably one in the pipeline.  However, you may be skeptical of the high-price tag that the equipment carries and its relevance to bench scientists.  After all, most of us teaching physiology aren’t clinicians, and we have neither the expertise nor the experience to teach medicine.  I was firmly of that opinion when the Texas Tech University Health Sciences Center first opened its simulation center, but I’ve tried to keep an open mind, and I’m happy to say that I’ve learned to incorporate these resources into my teaching.  More importantly, simulation works for the same reason the old dog labs worked:  it provides a clear and dramatic demonstration of fundamental physiological concepts.

Although the equipment available in most simulation centers is capable of reproducing some pretty sophisticated disorders, there is little need for such advanced capability during the pre-clinical years of medical training. The basics are more than adequate, and they can be covered adequately without obtaining a medical degree.   Cardiovascular physiology was my entry point using this new approach to teaching.  There are few things in life more fundamental than a heartbeat, and nearly every simulation center will have cardiopulmonary manikins that allow the student to practice auscultation.  This is not to say that heart sounds can’t be taught with alternatives, such as good digital recordings, but the use of manikins adds an important degree of realism.  I first ask the students to practice positioning the stethoscope for optimal detection of the various heart sounds in a healthy individual.  Demonstrating where to best hear the sound associated with pulmonary valve closure, for example, draws the connection between cardiac anatomy and physiology more closely together.  I then ask the students to explore various valve pathologies and illustrate what they would expect to see on Wiggers diagrams and pressure-volume loops.  The four murmurs that are most relevant to first-year medical students, aortic valve stenosis and regurgitation and mitral valve stenosis and regurgitation, are great starting points for illustrating the relevant changes in pressure that are associated with these defects.  For example, the combined use of auscultation and Wiggers diagrams make it easier to appreciate the excessive pressures developed in the left ventricle as a consequence of aortic valve stenosis.  It also makes it easier to understand how the high velocities of flow and resulting turbulence can cause the distinctive murmur.  In my class, I follow up the auscultation activity with standardized patients and ultrasonography, allowing the students to correlate the sounds that they hear with the coordinated movements in the heart, as visualized with the ultrasound probe.

The cardiopulmonary manikins provide a great resource for showing the practical relevance of hemodynamics to the clinical setting, but we must turn to high-fidelity manikins if we are truly to recapture the drama of the old dog labs.  I remember vividly the effects on an anesthetized dog when, as a student, I infused a sympathetic agonist or antagonist.  Now, as an instructor, I achieve a similar memorable effect with a full-blown simulation of hemorrhagic shock.  This is the capstone event in the cardiovascular physiology section of our course, when the students must recognize the problem and come up with a solution.  Our simulation center has rooms like you would find in the emergency department in which we place the manikins.  The potential “treatments” available for use by the students include a muscarinic antagonist, a sympathetic agonist, and the infusion of normal saline.  As I did with the dogs back in the day, today’s students apply various drugs or treatments to the manikin, and, from the attached control room, I can simulate the appropriate physiological response.  There are few things that bring home the importance of preload and stressed volume like the “recovery” evoked by rapid infusion of saline, especially if this follows unsuccessful attempts at treatment with various drugs.  Later in our class, we have additional simulations that illustrate fundamental principles associated with respiratory physiology and endocrinology.   I admit that it took some persuasion to convince my bench-investigator colleagues that they had sufficient experience to facilitate these activities.  However, after trying it a time or two, they usually find that the activities require more physiological knowledge and deductive reasoning than clinical skill, and, as an added bonus, they have fun.

So why not take advantage of that high-priced center that your medical school just built or is in the process of developing?  You’ll find that simulations provide hard-to-ignore demonstrations of physiology’s relevance to the clinics.  If my experience is any indication, your dean will be happy that you’re trying new things, and you’ll be rewarded by students who respond enthusiastically.

The nitty-gritty to get you started:

My colleagues and I have boiled down the use of simulation to a few key points that can provide a good start to your own efforts.

1)  Keep it simple.  You’re teaching physiology, not a subspecialty.  As described above, we require the students to recognize a loss of blood volume as the fundamental problem in hemorrhagic shock.

2)  Require a decision or intervention.  The students must follow a problem logically, putting into practice the physiology that they are learning.  In the hemorrhage scenario, they treat the “patient” with a rapid intravenous administration of saline.

3)  Provide some background material.  You’re providing a value-added experience that goes beyond simple lecture, but the students need some guidance to prepare.   For the shock simulation, they study a 20-minute online presentation focusing on low cardiac output the night before the activity.

4)  Do a debrief.  If things work well, there will be a lot of excitement and keyed-up emotion.  You’ll want to give the students a chance to talk things out and assess their performance as a team.

Good luck!

Pressley head shot

 

Thomas A Pressley is a Professor in the Department of Medical Education at Texas Tech University Health Sciences Center. After earning his undergraduate degree at Johns Hopkins University, he entered the graduate program in biochemistry at the Medical University of South Carolina. His postdoctoral training was in the College of Physicians and Surgeons at Columbia University. He was recruited by the University of Texas Medical School in Houston in 1987, and he transferred to Texas Tech in 1995. Tom has served as an interim dean, a visiting professor at multiple institutions, a member of grant review committees, and the chair of the Education Committee of the American Physiological Society. He is the current chair of the APS Career Opportunities in Physiology Committee. He has also developed numerous courses, and he has reviewed degree programs at several institutions.