Sunday, December 26, 2010

Medical consultation between doctors in our hospitals

Consultation between colleagues of different specialties about patients in our hospitals frequently ignores proper ethical principles and may therefore create problems and bad feelings.
1.     A junior resident doctor may send a consultation about a patient directly to a consultant in another department sometimes before the patient was seen by the consultant in charge. The proper way is that the consultant in charge of the patient should send the consultation. This ensures that he has seen the patient and that the consultation is needed. Not infrequently, the consultant in charge can solve the problem when he sees the patient or decides that it is not a priority and not needed at that time. It also avoids the possible feeling by the consulted doctor of being treated without due respect because the consultant in charge has not taken the trouble of writing the consultation himself. There may be an excuse for the junior doctor to do so in a case of emergency when time is vital and delay may harm the patient but this is not frequent and should be explained in the consultation letter.
2.     A consultant doctor may ask one of his juniors to respond to a consultation directed to him by a consultant colleague. This deprives the patient of receiving the best available opinion and is not good manners as it does not show respect to the doctor who consulted him. The proper way is that the consultant should respond himself if the letter of consultation has been written by a consultant colleague.

Wednesday, December 22, 2010

Time, the Enemy

A conference call for papers attracted my attention. The conference is the 33rd of the “International Association for Time Use Research” to be held in the University of Oxford (England) on 1-3 August 2011. The subject is time use. I entered “time use” in the search engine of Google which responded by showing 1,790,000 results including innumerable articles on time use research in different countries, sites of institutes of time use research and articles about how to manage your time properly because there is not enough time in the day for all you want to do. That brought to my mind the familiar sight in many cities of people reading in their pocket book while sitting in the train or the bus or waiting in a doctor’s room or even standing in a queue.
It also reminded me of the familiar sight in our country (and in others) of people spending most or all of their time sitting on street curbs or in street cafes doing nothing or indulging in some useless games. I remember once I was driving with a visiting professor in my car when we passed by a number of these cafes. Many of those sitting in the café were just rolling the beads of their rosaries (misbaha) and staring at the unknown. I said: it is a pity they are spending their time without a useful activity. The professor corrected: They are breathing! If you ask these people and many others doing all sorts of useless things about what they are doing many will give the familiar answer: we want to kill time. I do not know what made ‘time’ that hated enemy that deserves to be killed!

Friday, December 17, 2010

هل تقاس صحة القرار بنتيجته؟

من الشائع ان يحكم على القرار بنتيجته فان كانت جيدة اعتبر صائبا ونال صاحبه الثناء وان كانت سيئة اعتبر خاطئا وتعرض صاحبه للنقد. وهذا حكم غير منصف لانه يستند على المعلومات التي توفرت بعد اتخاذ القرار ولم تكن متوفرة حين اتخاذه. ان الحكم على صواب القرار يجب ان يعتمد على مدى حسن التقدير بناء على المعلومات المتوفرة حين اتخاذ القرار فان متخذ القرار لا يعلم الغيب وانما يبني قراره على الاحتمالات التي يتوقع حدوثها في كل حالة. ويتضح الامر بضرب مثال. فلو فرضنا ان شخصا اراد السفر من مدينة الى أخرى وكان هناك طريقان احدهما خطير نسبة الحوادث فيه 95% والاخر أمين نسبة الحوادث فيه 5% فاختار الطريق الامين ولكنه تعرض لحادث وان شخصا اخر اختار الطريق الخطر ولكنه نجى ولم يتعرض لحادث فهل نقول ان الاول اخطأ باختياره الطريق الامين وان الثاني اصاب باختياره الطريق الخطر؟
ان الحكم على صواب قرار ما يجب ان لا يعتمد على النتيجة وانما على صحة التقدير بناء على المعلومات المتوفرة حين اتخاذ القرار. ولو عمل الناس بهذا لقل بينهم الخلاف واللوم والتأنيب.
( ولو كنت أعلم الغيب لأستكثرت من الخير وما مسني السوء) – قران كريم (الأعراف 188)

Saturday, November 6, 2010

The use of ‘normal’ values

To judge a finding in a patient, be it body weight or height, a blood test like white cell count or serum potassium etc. we usually compare it with so called ‘normal’ values (better called reference values or range). These values are obtained by studying the frequency distribution of the finding (variable) in question in a sample of healthy people and determining its mean and standard deviation (SD). The normal range is taken as the range between + 2 standard deviations and -2 standard deviations.

(Normal frequency distribution curve with number of standard deviations on the horizontal axis)

We know from statistics that this will include 95% of people which means that 5% of healthy people have values outside the normal range. We have to remember then that if a patient’s measurement is slightly outside the normal range it still can be normal. Conversely if it is within the normal range it still can be abnormal for that particular patient because it is significantly different from his usual figure. For example a patient whose white cells count is 4000/ in normal circumstances the number may rise to 8000/ when he develops an infection. It is still in the normal range though it is raised compared to his count during health.
Like every thing else in medical practice data have not to be taken blindly and in isolation but have to be interpreted with caution taking all other findings to form an overall picture of the situation.

Monday, November 1, 2010

Changing medicine

Doctors who practice medicine for many years are struck between now and then by changes that turn their previous beliefs upside down. I say this with two examples in mind:
  1. The use of antibiotics in the treatment of peptic ulcer: Before the discovery of Helicobacter pylori and then establishing its relationship to the development of peptic ulcer no one would have been stupid enough to consider antibiotics when confronted with a patient with peptic ulcer. In fact mentioning it in an examination would have been a sufficient reason to fail the candidate in the opinion of many examiners.
  2. The use of beta blockers in the treatment of heart failure: Not many years ago we considered these drugs contraindicated in the presence of heart failure because they depress myocardial contractility. Now they are considered an essential part of the treatment of heart failure due to systolic dysfunction except when there is some strong contraindication like bronchial asthma.
 It makes one wonder which of the ideas that we consider now established facts will turn to be fallacies in the future and which of the forbidden practices nowadays will become established practices tomorrow. As they say, change is the only constant in medicine!

Friday, September 24, 2010

محاورة بين سقراط وافلاطون

المحاورة خيالية للدلالة على واقع وقد نشرت قبل سنين ولكنها تنطبق الان كما كانت عندئذ

Thoughts on Examination of Medical Students

Examining med. students.pdf - Google Docs
(If clicking the title does not open the article, please right click and open in a new tab or window)

Friday, September 10, 2010

The border between health and disease

The concept of health and disease, in the minds of most people and many doctors, is simple and clear cut. A person is healthy if he has no disease. Diseases are well defined and clearly recognizable conditions.
The reality is not so. Health is not the same in all so called healthy people. It covers a wide spectrum of conditions physically, mentally, and socially. Some people are physically robust, happy, psychologically satisfied, and socially integrated and active. Others are frail, easily tired, worried, frequently unhappy and socially isolated. And there are all grades in between. That is why the aim of medicine is not only to prevent or treat disease but also to promote health.
Apart from acute conditions like acute infections and trauma, the transition between health and disease is gradual and ill defined. Most symptoms of disease are present to some degree in so called normal people. All people become short of breath if they exercise sufficiently and "sufficiently" varies in various people. Some may need to climb fifty stairs to become short of breath. Others may become so after climbing thirty or twenty stairs and so on. People with heart or lung disease may become short of breath on climbing ten stairs or one or two depending on the severity of their illness. What is the number of stairs that makes shortness of breath pathological? Can we put a definite figure? You can say the same about poor appetite, headache, anxiety, numbness, poor memory, readiness to fall asleep on going to bed, muscle and joint pains and so on. Recognizing a symptom as abnormal or pathological varies widely between people. That is one of the reasons why some people go to the doctor frequently and sometimes for no good reason, while others do not go unless they become severely ill.
A similar thing can be said about laboratory tests, but in this case artificial, statistically derived, boundaries have been created by putting a reference range for every test. These reference ranges have come to be generally conceived as the boundaries between normal and abnormal test results. According to these boundaries, a test result can deviate from the average of normal people to a large extent and still be considered normal. Then when it crosses the artificially drawn boundary it suddenly comes to be regarded abnormal!! The transfer from health to disease is not that sharp in real life.
The spectrum of health is wide and so is that of disease and the border between the two is frequently blurred and difficult to discern.

Sunday, August 29, 2010

Classification and probability

Classification is the process of putting people, animals or things into groups or classes according to certain characteristics. So we classify people into children and adults according to age or men and women according to sex. We may subdivide adults into young, middle aged and old according to certain limits of age that we allocate for each group. We may classify diseases according to the organ they primarily involve into e.g. heart diseases, lung diseases, kidney diseases and so on.
Sharing a certain characteristic may indicate sharing other characteristics e.g. old people may be more prone to certain diseases than younger adults or children. These classifications which deal with groups have important effects on our dealing with individuals. In medicine we usually translate the occurrence (incidence or prevalence) of a disease in the group into a probability in the individual. For example, if 50% of old people have osteoporosis, when we have an elderly patient we say he has a 50% chance (probability) of having osteoporosis. If 80% of heart failure in elderly people is caused by atherosclerosis and we have an elderly patient with heart failure we think that the cause of his heart failure is atherosclerosis with a probability of 80% and so on. This translation of occurrence into probability is logical. However it may lead to an erroneous conclusion if done blindly. The following example explains this.
Students are taught that in children nephrotic syndrome is caused by minimal change glomerulonephritis in 80% of cases while only 20% of cases in adults are caused by minimal change disease. The most common cause of nephrotic syndrome in adults, they are taught, is membranous glomerulonephritis. Consequently when they see an 18 or 20 year old man with nephrotic syndrome and you ask them what the most likely cause of his nephrotic syndrome is, many will answer membranous glomerulonephritis because he is an adult. The answer is the effect of classifying adults who represent a very large and heterogeneous collection as one group or class. When adults are taken together membranous glomerulonephritis is the most common cause because the group includes many middle aged and elderly people in whom this disease is the commonest cause. That is not the case in young adults. The 80% likelihood of a minimal change disease being the cause of nephrotic syndrome in a child does not dramatically drop to 20% when the child reaches an age that puts him in the adult category. Nature does not change its behavior according to the limits we use in our classification. The 80% chance in say a 5 year old child may become 75 in a 10 year old, 65 in a 15 year old and 60 in a 20 year old. The probability may drop to 20% in a 40 or 50 year old and to less than that in a 60 or 70 year old man (these imaginary figures are only to explain the idea and are not claimed to be real). In other words minimal change is still the most likely cause of nephrotic syndrome in the very young adult and its probability decreases gradually as the age advances. Classification helps us to understand and remember various scientific facts but we have to keep in mind that the sharp boundaries between classes or subclasses are frequently artificial. They are created by us and not necessarily present in nature.

Friday, August 27, 2010

Relative risk and absolute risk

Statistics can be deceiving if one is not careful. We learn of things that double our risk of developing this or that disease or increase it by say 25 or 50%. We also learn of things that decrease our risk of developing a disease by a certain percentage. It may sound very important to have a risk doubled or reduced to half but unless we know how much it originally was, can we really tell how much the change is? If you get a job and your boss tells you that your salary will be double the salary of Mohammed you immediately ask: How much is the salary of Mohammed? We do not do the same when we learn about doubling or halving the risk of a certain condition.  We do not bother to know how much the original risk was. Unless we translate a relative risk (i.e. a risk expressed as a ratio of another risk) into an absolute risk (i.e. the chance of developing an event regardless of how it compares with another risk) we cannot judge its magnitude and importance. For example, if you know that smoking increases your risk of developing a cardiovascular event in the next 10 years by say 50% and your absolute risk is already 20%, the increase is 10% which is important and worth avoiding smoking (leaving aside other harms of smoking). On the other hand if someone tells you that using your mobile phone increases your chance of developing an acoustic nerve tumour by 100% and your statistical chance of developing this disease (i.e. your absolute risk) is 1/100,000 then using the mobile phone will increase it to 2/100,000 i.e. an increase of 1/100,000. Most people will consider this increase, even if it is true, insufficient to make them stop using mobile phones. I can mention other examples of things that decrease the risk and the same thing applies.
We should always remember that it is the absolute risk that counts.

Monday, August 23, 2010

Our maintenance dialysis policy

Because of the poor dialysis situation in our country (and in similar so called developing countries) we do not usually start our patients on maintenance dialysis early. Most patients have obvious uraemic manifestations when they are started (Creatinine clearance usually 5ml/min or less). Some in fact start their dialysis as an emergency life saving procedure. In contrast most patients with chronic renal failure in developed countries start dialysis as a carefully planned procedure before they develop obvious uraemic manifestations (creatinine clearance of 10 ml/min or more). We have been told that early dialysis improves survival and quality of life.
In a recent randomized controlled trial (called Initiating Dialysis Early and Late –IDEAL) conducted at 32 centers in Australia and New Zealand and reported in the August 12 issue of the New England Journal of Medicine(1); Bruce A. Cooper from Royal North Shore Hospital and Sydney Medical School in Sydney (Australia) and Colleagues examined whether the timing of the initiation of maintenance dialysis influenced survival among patients with chronic kidney disease. Between July 2000 and November 2008, eight hundred twenty eight adults (542 men and 286 women) with progressive chronic kidney disease were randomly assigned to an early start group (creatinine clearance between 10 and 14 ml/min) and a late start group (creatinine clearance between 5 and 7 ml/min or the development of obvious uraemic manifestations). At the end of study the authors concluded that planned early initiation of dialysis in patients with stage V chronic kidney disease was not associated with an improvement in survival or clinical outcomes. In an accompanying editorial, Norbert Lameire and Wim Van Biesen from the University Hospital Ghent in Ghent, Belgium commented : "In our view, the IDEAL trial supports the currently recommended practice, in which most nephrologists start patients on renal-replacement therapy on the basis of clinical factors rather than numerical criteria such as the estimated GFR alone,"
Our dialysis policy may after all not be as bad as we think!!??

(1) Cooper BA, Branley P, Bulfone L, Collins JF, Craig JC, Fraenkel MB, Harris A, Johnson DW, Kesselhut J, Li JJ, Luxton G, Pilmore A, Tiller DJ, Harris DC, Pollock CA, A randomized controlled trial of early versus late initiation of dialysis, N Engl J Med, 2010,363(7):609-19.

Thursday, August 19, 2010

Decision making in our daily medical practice

In any action we take in our daily life we, consciously or not, consider the benefits and harms before deciding to do it. Although we do not make accurate calculations and construct decision trees, we make a rough judgment based on our knowledge and experience. This should certainly be the case when we take any decision concerning our patients. The benefits and harms differ in each individual situation and cannot be generalized. For example, you may put a man with paroxysmal atrial fibrillation who has a prolonged attack every several days or few weeks on long term anticoagulants but you do not do the same with a man who has a short attack every one or two years because you judge that the possible harm of the drug outweighs its benefit. Even if you have two patients with the same frequency and duration of attacks you may put one who is intelligent, educated and has a good laboratory within reach on long term anticoagulants and refrain from doing that to one who is not intelligent, not educated and has no reliable laboratory within reach. You may decide to give a hypotensive drug to a man who is obese, diabetic, heavy smoker, has high cholesterol and has a mild hypertension. In a different way you may be satisfied with an advice of change in diet and life style and follow up in the case of a man with the same level of blood pressure who is slim, not diabetic, non smoker and has normal cholesterol. The trade-off between the benefits of the drug and its side effects is different in the two situations. I can mention innumerable examples concerning various actions like asking for certain investigations, admitting patients to hospital, surgical operations and so on. The writers of medical books and journal articles can only give general guidelines on how best to behave in various situations. They cannot put themselves in your shoes in every possible situation you are likely to meet in your practice. These facts are even more important in the case of doctors practicing in developing countries and guided by books and journals written by people practicing in highly advanced institutions in developed countries.
Do we in our medical practice give enough thought and time for every decision and action we take with every individual patient in the same way we do with other actions we take during our normal daily life??

Friday, August 13, 2010

Science and art in the practice of medicine

Medicine is said to be a mixture of science and art. The question is which part is science and
which part is art?
Science is knowledge based on information obtained through human senses (sometimes aided with various instruments) by observation and experimentation and by logical conclusions derived from this information. Its contents are measurable and reproducible (i.e. gives the same result when repeated by the same or a different person) and it follows strict rules and laws.
Art is a human activity which depends on ill defined characteristics like judgment, intuition, gift and experience. It is not readily measurable, not reproducible and does not usually obey strict rules and laws.

Science in the practice of medicine:
Modern medicine depends to a large extent on various biological sciences like physiology, biochemistry, anatomy, pathology, microbiology, pharmacology etc. It is also increasingly dependent on modern technology which in turn depends on sciences like physics, chemistry and mathematics. The modern doctor, at least the good one, is scientific in his approach to patient's problems. He does not presume that illness is produced by an evil spirit which he should rid the patient off by beating him, or that it is the result of some change in body mixtures for which he has no evidence. Instead he defines the problem, makes a preliminary hypothesis about diagnosis, collects evidence, formulates a main hypothesis, tests it, if valid applies it and if not rejects it and looks for another one. This approach is the same that modern scientists follow when they tackle their problems, the so called "the scientific method".

Art in the practice of medicine:
The first thing a doctor does when he meets a patient is to take the history of the illness. This doctor-patient encounter contains so many things that are not measurable, not reproducible and not controlled by strict rules and laws. The look on the face of the doctor, the tone of his voice, the choice of the questions and the wording of them, the way he listens or interrupts all fall more in the realm of art than science. The doctor tries to give the proper weights for various symptoms but can he measure pain, nausea, or dizziness? Through experience he may attach great importance to some symptoms and trivialize others.
When he feels the abdomen he does not have a measure of the pressure he applies with his hand, and no units with which he accurately measures the tenderness or the consistency of an enlarged liver. If he repeats the examination or some one else does, he may give a different estimate. When he listens to the heart or the chest, he does not usually use a device which measures heart sounds, breath sounds or murmurs in an accurate and reproducible way. The same thing applies to examination of reflexes, mentality, speech, joints, muscles, masses etc.
When he decides to do some tests, has he strict rules which tell him what test should be done and what should not? Or is it a matter of vague ill defined judgment on how much is the test likely to be useful and how much is it likely to be a waste of time and a cause of needless suffering and possible harm?
The same applies when he decides on treatment. Treatment may produce benefit and may do harm. The balance between the two usually depends on that vague thing we call "clinical judgment" which we cannot define, cannot measure and which may vary between different doctors and in the same doctor at different times. It is not measurable and not reproducible.
All these activities fall in the category of art. I can mention a lot more in various fields of medical practice like surgery, obstetrics, pathology etc. and about various procedures which require, beside judgment, manual skills.
This part of medicine, the art of it, is usually learned by experience and by working with someone who is good at it. Reading books and attending lectures is not the way to improve it. This is one of the defects in our medical education system. Students concentrate on the science part of medicine. The art of medicine, which is extremely important in medical practice, is to some extent neglected. We cannot put all the blame on students. Many examiners do not concentrate on the art of medicine when they assess students in clinical examinations. Assessing the art of medicine requires a skill which only experienced examiners have.

Saturday, July 31, 2010

Medical practice: Is the textbook always right?

Most practicing doctors in developing countries feel the gap between their practice and the book. They usually regard what is in the book as the correct thing and anything short of or different as incorrect or inferior. Textbooks are usually written by doctors working in highly advanced institutions in developed countries, which frequently provide tertiary care. The situation in most hospitals and clinics in developing countries is quite different.
The aim of the doctor is to do what is in the best interest of his patients in the environment he or she is working in. This should be the yardstick by which a certain behavior is judged as right or wrong. What is an appropriate decision in one place may be inappropriate in another. Sticking to the book is not always the proper behavior. Here are examples of this at various stages of the relationship between doctor and patient.

Physical Examination
Examining women is a special problem in our community when the examiner is a man. They frequently resist exposing parts of their body. Some may request to be examined with their clothes on. The doctor has then two choices. One is to refer the patient to a female doctor. The patient frequently does not like that either because she trusts the doctor she has come to and wants to be treated by him or because of the inconvenience of having to go to a different place and have another appointment. The second choice is to do what the patient wants and examine her with clothes on.
The doctor has to judge whether such an examination is acceptable in the circumstances. Examining the abdomen for example with a thin internal cloth on does not interfere significantly with palpation, percussion or auscultation but it interferes with inspection. In some cases, it may be reasonable to assume that this is unlikely to affect your judgment and doing it should not be considered wrong. Taking blood pressure with a thin sleeve on usually does not interfere significantly with measurement(1) and doing it to a patient who wears a sleeve that cannot be rolled up is another example.

Many tests done in our laboratories are not as accurate as they are in the place of the writer of the chapter in the book. The values given to them in the book in the form of sensitivity, specificity, predictive values and likelihood ratios may be quite different from the values they have in our actual practice. Their weight in the diagnostic and management process may consequently be considerably less than the weight given to them in the book. In other words, their value compared to the information obtained by history taking and physical examination may be considerably less than what is stated in the book. This should always be kept in mind in making a final judgment on diagnosis and management. It should also reflects on the decision to do the test in certain situations when the probability of a diagnosis or a management action built on clinical criteria (pretest odds) is high and the likelihood of it being affected by the test result is low. For example, if you have a very strong suspicion of typhoid fever on clinical grounds and the reliability of your laboratory is questionable, it may be prudent to treat the patient without wasting time and money by asking for a Widal test.

A certain treatment, especially complicated procedures, is advised when it is judged that its possible benefits outweigh its possible harms for the patient concerned. Consequently, it should be judged according to the situation in the place of practice. It should not follow the instructions of the book blindly. Those who write book chapters usually work, as stated earlier, in advanced institutions with higher expertise and better facilities. The results of various therapeutic procedures and their complications are not the same as they are in less developed places. Consequently, the balance between benefits and risks is different. So, a treatment, which according to the book is indicated in a particular situation, may not be indicated for the same situation in the place one is working in. Dialysis is an example. In a place where maintenance dialysis is good with few complications and a reasonable quality of life of patients, one may advice patients with chronic renal failure to go on maintenance dialysis when their creatinine clearance comes down to 10m./min. One would expect their life on dialysis to be better than it is without it and their long-term prognosis better. In another place where the quality of maintenance dialysis is poor and complications are many, one tend to wait longer until the patient's condition becomes severe enough so that their life on dialysis in spite of its poor quality and frequent complications represents an improvement on their life without it. The policy may then be to wait until creatinine clearance comes down to 5 ml/min. before putting the patient on maintenance dialysis as it is indeed the case in less developed parts of the world(2).

I. Hoysrpian R, AI-Haddad M, and Abdulla K: Comparison of blood pressure measurements in bare arm, clothed arm and forearm. J Fac Med Baghdad, 1996; 38: 221-4.
2. Swyter J: International ESRD experience: An anthropological perspective. Dialysis and Transplantation, 1985; 14: 328-38.