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Is the new professionalism and ACP's new ethics really just about following guidelines?

The Charter ( Medical Professionalism in the New Millennium.A Physician's Charter) did not deal with just the important relationship of ...

Wednesday, September 07, 2016

Endurance exercise athletes heart works differently from the untrained but how much is training and how much genetic?

The exercise physiology party  line had been for years-probably fifty or more- that as one increases his level of exercise, both heart rate  and stroke volume (SV) increase together up to a point. That point is around a heart rate of around 120 or a work load of about 40% of  02Max at which time the SV levels off. The thinking was that at higher heart rates diastolic filling time will become  so limited that SV would flatten out at a relatively low heart rate More recent data indicate that while  that pattern is what happens when the untrained person exercises  a different pattern has been observed in ( at least some) well trained endurance athletes and this difference may be due in part to impressive diastolic function .

The endurance athlete continues to increase the SV to levels higher than the text book limit of a heart rate of 120  and several authors including Gledhill et al ( ref 1 below) showed no plateau to the SV in heart rates up to 200 beat per minute in trained endurance athletes. Their ability to continually  increase stroke volume was attributed to not only enhanced ventricular emptying but to a even greater increase in ventricular filling.The left ventricular ejection time was longer and the diastolic or filling time was shorter. Not only could they push blood out better they could suck blood into the ventricle even  better.

This enhanced ventricular filling make the endurance  trained group better able to use the Frank Starling mechanism. ( Shifting the curve up and to the left) Further the greater blood volume seen in endurance athletes helps maintain adequate filling pressure and end diastolic volume given the shortened filling times that occur with heart approaching 200 bets per minutes. The greater ability to empty out the ventricle leads to a greater recoil from a lower end systolic volume with a greater suction effect enabling better filling.

The athletes were able to , for example, refill the ventricle with each 188 ml stroke volume in 0.1 sec.

Levine and co workers have shown similar patterns of  enhanced diastolic function in older endurance athletes.  (ref 2)

 Gledhill compared young ( average age 22) untrained subjects with a 02 max of about 40 with a trained group with  02 max of 60 plus. ( Group average for  the untrained was 44 versus 68). So the trained group has 02 max values typically associated with folks who can run a sub-three hour marathon.  A trained person with a baseline of 44 V02 max  would be expected to be able to run a marathon in under 4.5 hours. (Estimates are from data of Davies and Thompson as depicted in table 2.3 in Noakes' Lore of  Running, 3rd edition.) Obviously Gledhill's endurance trained group  were rather far out on the curve of ability to exercise  and though they trained hard you have to wonder how high was their 02 max before training.

The authors of this and several similar articles hoped to study how fitness levels modify the heart and vascular system response to exercise. However the authors realized that this type of cross-sectional study cannot tease out the effect of  training from the effect of genetic endowment,
 
Quoting Gledhill:

"It is not possible to state with certainty ,based on these findings, that the difference in cardiac function between endurance trained athletes and normally active individuals is an adaptation to endurance training,a consequence of genetics or a combination of these influences."

 So far all of this seems little more than inside baseball physiology talk but could there be a broader significance ?

A optimistic " maybe" seems to be the view of Dr. Benjamin Levine of Southwestern Medical School (see reference number 3).

Levine's et al showed that there was some preservation of diastolic function-i.e ventricular compliance as measured by echocardiography  (E/a ratio etc) as a function of the amount of long standing aerobic exercise and it seemed proportional to the amount of exercise. Long term exercisers had better compliance ( aka measure of ventricular stiffness) while measurements of "relaxation" decreased in the exercisers to about the same degree as the sedentary group-this was measured by the relaxation time (IVRT) of the left ventricle.

On the other hand Hirofumi Tanaka et al from Colorado  (see reference 4) concluded that the compliance was not preserved in the long term exercisers ( though some of his data was consistent with that hypothesis) while  there was a beneficial modulation of the age associated stiffness in the large elastic arteries ( as measured by the aortic pulse wave velocity)

 Levine ( reference 5) has suggested that the long term endurance exercise ( maybe as "little" as 2-3 hours per per week) can prevent the decrease in left ventricular compliance associated with aging and/or inactivity and perhaps have important implication for prevention of cardiovascular disease ( ie. diastolic heart failure).  While, in my opinion,the evidence for this is a something less than overwhelmingly convincing this  is a  reasonable possibility and it would be very nice to think so, particularly to someone who has done a lot of running over the years.


A mechanism by which exercise may help to maintain  ventricular compliance has been outlined by Hyo-Bum Kwak ( ref 6) on the basis of rat research into apoptosis or programmed cell death and exercise. Myocytes decrease in the aging heart and this is in part thought be due to a mitochondrial-mediated apoptotic pathways. Kwak has shown that exercise training decreased these apoptotic pathways .



 "Reason is, and ought to be, the slave of the passions and can never pretend to any other office than to serve and obey them." David Hume


references:

 1.Gledhill, N. et al  Endurance athlete's stroke volume does not plateau:major advantage in diastolic function.Medicine and Science in Sports and exercise,26, pp 1116-1121, 1994

2.Levine, BD et al. Left ventricular pressure volume and Frank-Starling relations in endurance athletes.Circulation 84:1016-1023.1991

3.Prasad,A The Effects of Aging and Physical Activity on Doppler measurements of diastolic function. Am J Cardiol 2007, 99, 1629

4.Tanaka, H Endurance exercise performance in Master's athletes age-associated changes and underlying physiological mechanisms.  J Physiol 586, 2008, 555-58

5.Bhella, P Impact of Lifelong exercise "dose"on left ventricular compliance and distensibility
JACC 641257-1266,2014

6. Kwak,H , Effects of aging and exercise training on apoptosis in the heart. J exer Rehabil 2013 apr 212-219

Friday, September 02, 2016

Health care with other people's money- what could be wrong with that?


Paying for health care with other people's money-what could possibly go wrong?

Dr. Paul Hsieh answers the question posed in the title in a commentary in Forbes. See here.

He outlines four important ominous consequences of basing health care on spending other people's money.

  This excellent article should be read in its entirety but let me briefly  comment on the first in the list.

"Doctors will be increasingly expected to save money for the system  ."

This is already happening.Various medical professional organizations are re-writing traditional medical ethics, pushing the fiduciary duty of the physician to the patients into the memory hole and substituting the bogus concept of the physician as a steward of society's medical resources which at least one physician's organization (the ABIM Foundation) has strangely linked to social justice. I have ranted about this before but the caravan rolls on and increasingly  the rhetoric  in various medical forums emphasizes saving money for the system. It seems that the medical professional elite would have us believe that the road to social justice is for physicians to follow guidelines, which may not be designed for patient benefit alone but also for cost containment for the third party payers.

The medicine of the collective is replacing the medicine of the individual. This is being promoted in part by what I have called the progressive medical elite who, to a frightening degree, seem to occupy the leadership positions in many influential medical organizations . Their unspoken mantra is that medical care is too complex and too important to be left to the individual patient and his physician. Wise leaders with ideas need to be in charge. Of course, it is promoted by the third party payers, private and public who may well consider the medical professional  elite in this ethical paradigm shift as useful idiots.

 The third party payers and the professional medical elite have attempted to turn traditional medical ethics around so that the fiduciary duty to the patient is somehow replaced by an ethical duty to save money and the whole flim-flam activity is sprinkled with non sequiturs  about social justice. Social justice is typically taken to mean redistribution and if cost to the system is reduced it is difficult to see wherein the redistribution lies if everyone gets less.Everyone, of course, except the third party payers.

  In regard to private property the owners have the incentive to be a "good steward" of theirresources.You have to ask what is the incentive of physicians to act as stewards of a mythical  collectively owned resource? 

The notion of "the system" [in regard to medical care] while a rhetorically useful notion for a certain agenda, is basically fallaciously  aggregating elements that do not belong together. In short, there is no system for health care just as there is no car delivery system or a home building system. It makes no sense to speak of the situation in which someone buys a new car as a cost to the car supply system or a person buying a home as a cost to the home supply system.All of these are transactions in which there are buyers and sellers and exchanges take  place.Mr Jones gets a CT  of  the abdomen.. This is not a cost to any system. It is a cost to Jones and/or his insurance company while to the providers of care it is a payment. One person's cost is another person's income.To call this a cost to a system is nonsense.Unless all the health care is provided, operated and owned by  a single entity, usually the government., then the services provided  could be considered  a cost to the system.

Who gains from acceptance of this bogus notion of physicians as stewards of some mythical collectively owned medical resources? The third party payers for whom the gain is obvious and the medical elite progressives who stand to gain from their position of prestige  as experts and rule makers  and the rest of us,physicians and patients,  lose.

So, in summary there is no medical care system to which a cost is charged with every medical care transaction and secondly the physician as steward concept is completely contradictory to the traditional role of the physician as the fiduciary agent of the patient .


Thursday, September 01, 2016

What is going on with the price of the Epipen?

 Scott Alexander on his blog Slate Star Codex offers this insightful explanation of what is going on with the price of the Epipen and why are there not cheaper substitutes available in the US. Actually Alexander tells us this is one.See here.

John Goodman tells a similar story here.


Disclaimer:
 I have never actually used an Epipen but in an ill planned effort to dispose of an out of date pen I managed to drive the needle through my thumb.


Wednesday, August 03, 2016

New high school football season advice-don't let your babies grow up to be defensive backs

 Extracted from an article  from AANS regarding traumatic brain injury (TBI) data from 2012:

Defensive backs in American football are at the greatest risk for both fatal head injury and serous cervical spine injury.:

"The majority of catastrophic injuries occur while playing defensive football. In 2012, two players were on defense and one was in a weight lifting session. Since 1977, 228 players with permanent cervical cord injuries were on the defensive side of the ball and 55 were on the offensive side with 44 unknown. Defensive backs were involved with 34.6 percent of the permanent cervical cord injuries followed by member of the kick-off team at 9.2 percent and linebackers at 9.5 percent."

Spending even a small amount of time watching high school,college and professional football on TV makes it seem obvious that the vast majority of high impact collisions occur in the defensive zone involving defensive backs and either runners or receivers and on kickoffs.Quarterbacks receive many hits with the helmets impacting the ground and have a significant risk of concussion but apparently have  lower risk of fatal injury or injury leading to permanent disability.Offensive and defensive  linemen may receive more sub-concussive head blows over a game or a season and whatever the long term consequences of that may be  seem less likely to regularly  be involved in high impact collisions and therefore less at risk for serious brain or cervical spine injury. There is a reason for ambulances to be  parked near the playing field of high school football games attesting to the cognitive dissonance of some of  the  parents cheering them on.The EMTs are not on site to help manage sprained ankles.

Don't let your babies grow up to be defensive backs.

Notice: This is a lightly edited and altered version of an earlier commentary on this blog. As  I see high school kids  on the practice field in early August in Texas with heat indices pushing 105 my antipathy to high school and youth football  flares again.




Monday, August 01, 2016

Another football season begins, what do we know about sports related head trauma

What do we know about head trauma in high school and college football?

Mild Traumatic Brain Injury ( mTBI) encompasses the clinical entity of concussion. Concussion is defined as a trauma induced alteration of mental status with or without loss of consciousness.

Considerable research has been published regarding concussion and recently  research has been published about the multiple blows to the head that occur in all levels of football in  the absence of a recognized concussion. These "sub-concussive blows" have become the target for various types of brain imaging and cognitive function testing and the results have raised concern about the long term effects on the brains of highs school and college players.

 Some of what we know is :

1.While conventional MRIs and CTs in concussed high school and college football players are normal , Diffusion Tensor Imaging (DTI) and functional MRI have shown abnormal findings some of which may persist for weeks or months. Additionally subtle impairments of verbal memory and other cognitive tests have been reported in concussion cases persisting past the time during which the player has any symptoms.The long term significance of these finding is not known.

2.Similar imaging findings and cognitive testing results are being reported in high school and college players after a season of participation in football even thought the players had no reported concussive event.

3.We know that football helmets do not prevent concussions.

4.We know that at least  some  college level contact sport athletes decades later show abnormal white matter by Diffusion tensor imaging and lowered test results on cognitive testing but again we don't know if these changes are a predictor of later symptoms of CTE.

 Some of  what we don't know is :

1.We do not know what pathological changes underlie the imaging findings. Do the scan results indicate transient damage and tissue repair without likely long term sequelae? Is there a recognizable subset of these players with these findings who if  they continue to be exposed to multiple head blows over many years will develop Chronic Traumatic encephalopathy (CTE)? How can those who may be destined to develop CTE be distinguished from the vast majority of players who never will  have those problems

From  the wide range of head hit exposures in those NFL players who have been diagnosed with CTE the obvious implication is that there must be a fairly wide range of thresholds. There are reports of NFL players with as little as five years of play showing  typical pathological findings at autopsy. Further there has been at least one case of a college player diagnosed with CTE.


2.the long term cognitive changing on various tests  and brain imaging abnormalities have been   demonstrated  in  contact sport athletes in college and high school who did not experience a concussion.

 After the last high school football season ending there were reports of 13 fatalities.   This is about average for the years following the meaningful changes made in the rules and the instruction of techniques of blocking and less dangerous ways to tackle. Better helmets probably prevent skull fractures but not concussions.Can you imagine the outcry if high school boys were forced to take part in an activity that results in deaths each year?

See here for details  of some  of those deaths. Tragically it seems that two were due to heat stroke, all were not due to head injury.In reading over the cases it seems reasonable to designate two of the deaths to the second hit syndrome.

You see the same parents who carefully made sure their kids did not ride tricycles without  wearing helmets are some of the same ones watching and yelling at Friday night football games and probably do not see the irony  of common practice of there being an ambulance at the stadium. If their son is the victim of the second hit syndrome, probably an ambulance won't help.

Note: Much of this posting is a rewrite of another commentary from last year which I shamelessly re-post  now with only  a few additions  because this topic is one I obviously feel strongly about .I used to really enjoy watching professional and college football on tv now I only occasionally watch  just to sample the action to notice obvious head trauma. Professional players increasingly are able to make some effort at an informed decision to play with considerations of the risk to their brains, high school kids and younger much less so. 


Monday, July 11, 2016

Is the new professionalism and ACP's new ethics really just about following guidelines?

The Charter ( Medical Professionalism in the New Millennium.A Physician's Charter) did not deal with just the important relationship of the physician and the patients but presumed to define what the relationship of the physician  should be to society. The physician was to strive for social justice and was to act as the "steward of society's " finite medical resources.

Implicit in the stewardship of resources notion is the egalitarian concept of the collectivization of  privately owned resources i.e all of the assets and individual skills that constitute the medical resources. This is the view that resources as a whole should be considered as the common asset of everyone with each to have a right to their share or that the resources are "owned" by everyone.  This notion is antithetical of the notion of private property and seemingly ignoring the key role of  private property concepts as the basis for civilization, At least that is what David Hume,Adam Smith, John Locke and founding fathers thought about the importance of private property.

Owned is in scare quotes because the concept of ownership in a free society with rule of law entails the right of the owner to use his property,to exclude others from use of his property and the right to dispose of the property.If everyone owns the resource then no one owns it and no one could be excluded from use of the property.

All of the  medical resources of the United States cannot in any real sense or legal sense be owned by everyone. So the common ownership rhetoric must be metaphorical and physicians as stewards of the resources must be rhetorical as well. It is a poetic way of saying the physicians should rein in the ever increasing cost of medical care. Further they can do that  by ordering fewer tests and procedures and treatments,that they should abide by recommendations based on studies of cost effectiveness of various medical options, that they should not let their concern and duty to the individual patient override the collective good which will be brought about by doing what is best for the group and what will be best will be determined by the progressive medical elite.Just follow the guidelines,Doc.


Tuesday, July 05, 2016

The 4th of July, Pride and "How Can I help you/"

This blog is for the most part about medicine and the practice of medicine so quoting extensively from a economist's blog might seem off track and one may wonder what if any is the link to medicine. This recent posting by George Mason University's professor, Don Boudreaux is so congruent with my core beliefs and he expresses them so well  that I have to quote him.

Broudreaux's topic is why, on the 240 th anniversary of the United States, we should be proud to be an American. See here for the entire essay.

Quoting from his blog, Cafe Hayek:

"...I’m proud of the peaceful manner in which most Americans conduct their private affairs.  I’m proud of the widespread respect for private property that continues to govern people’s personal, private relations.  I’m proud of the entrepreneurial spirit that continues to exist among many of my fellow denizens of these United States.  I’m proud of – and deeply grateful for – the innovativeness and entrepreneurial creativity of many of my fellow Americans.  I’m proud that America continues to be a destination for people seeking better, freer lives.  I’m proud that many Americans continue to believe that the most ethical course in life is for each individual to be self-responsible, self-supporting, hard-working, honest, and upright.

I’m proud, in short, of America’s bourgeoisness.  It’s this bourgeoisness that has made America great.  This greatness comes not from bellowing politicians, not from well-weaponed armies, not from arrogant judges, not from meddling bureaucrats, not from pompous Washington and New York and San Francisco pundits; it comes not from anything but the hundreds of millions of ordinary Americans who daily work hard, honor their contracts and other people’s property, cherish their families, friends, and neighbors, and think it perfectly natural to ask strangers in commercial settings “How can I help you?” "

 It has always seemed natural for a physician to ask that same question upon seeing a patient. In fact I recently saw an orthopedics for pain in my calf who asked that exact question.

As I read commentaries about the MACRA proposal and the nearly 1000 pages it takes to describe the process I wonder how long as the bureaucratic interference levels continues to increase and impede medical practice  will it be before that question will be merely perfunctory as more and more time and effort will be drained  away in an effort to go by the rules of " quality care" and properly document them so the reimbursement  will be 3 or 4 % more or less ( see here) and less available to do what is needed to help the patient.

Addendum; For an excellent  review of how MACRO will change just the "Meaningful Use" program (and there is much more to it than that) see here.

 h/t to Margalit Gur-Arie on her blog "On Heath Care Technology"