That we no longer have to apply this standard procedure is thanks to a macabre experiment conducted on an unsuspecting eleven-year-old orphan. Little James Greenlees had fallen under a coach in Glasgow. His shinbone was broken and was sticking out through the skin. The wound was full of the dirt from the street. Without amputation, he would certainly have died, as gangrene would have developed. Yet Joseph Lister spared the boy an amputation. On 12 August 1865, rather than cutting off the leg, he sprayed the wound with a corrosive liquid, carbolic acid. This experimental treatment proved successful, James’s life and his leg were saved, Lister was made a lord, and antisepsis – the use of antiseptics to treat wounds – was born. No one asked whether the manner of this discovery was justifiable. It was apparently quite normal to experiment on children.
Peter Stuyvesant’s defeat was a fiasco. The Spaniards must have laughed out loud. But the Dutch refused to give in and, in the days that followed, made a series of further futile attempts to attack the Spanish fort, from the land and from the sea. One of the ships deployed was the Blauwe Haan, on which Stuyvesant was recovering from his amputation. It was hit by three cannonballs. On 17 April, exactly four weeks after they had arrived, the Dutch retreated with their tails between their legs and the island of San Martin remained Spanish for another four years.
Peter Stuyvesant returned to the Netherlands. With one leg, he was no longer fit for the life of a seagoing merchant, so the company gave him a desk job on shore. He was made director-general of the colony of New Netherland, where he became the first mayor of New Amsterdam, a settlement on the island of Manhattan. An amputation clearly did not always mean the end of a career. However, a regular seaman who had lost a limb could not usually count on such a favourable return to duty. They would usually be discharged and end up as beggars on land or go back to sea as pirates.
In 1664, the village of New Amsterdam was captured by the English, who would rename it New York. Stuyvesant went back to the Netherlands, but returned to New York later to live as a normal citizen. He died there in 1672, at the age of sixty-one, and is entombed in St Mark’s Church in-the-Bowery.
In 1648, the Dutch retrieved Saint Martin under the terms of the Peace of Münster. At least, half of it. The French colonised the north of the island (Saint-Martin) and the Dutch the south (Sint Maarten). But, although both colonies lived in harmony for nearly four centuries, everyone on the island speaks English. The magnificent salt-pan behind Great Bay is now home to the national landfill site.
12
Diagnosis
Doctors and Surgeons: Hercule Poirot and Sherlock Holmes
THERE WERE TIMES that, when visiting patients, doctors did not so much as lift a finger to examine them. Perhaps they felt they were too good for such mundane concerns, or were afraid of catching a disease themselves. Patients in Asia and Arabia used a figurine of wood or ivory to point out where they felt pain. Whether the doctor listened to them is a different matter. Often, even that was pointless, as doctors had no effective treatment to offer. What they prescribed was always the same: enemas via the anus, purging via the mouth and a panacea, a medicine that would help against all complaints, such as the cure-all theriac, a pill made of Venetian snake cookies. The contrast with the surgeon was enormous – he did everything with his hands. And his treatment was much more specific than that of a doctor. After all, there is no panacea in surgery – you can’t treat one complaint with an operation for a different one.
Fortunately, much has changed in medicine. Treatment by non-surgical doctors became equally valuable and specific. Yet, a gap has always remained between the two professions regarding involvement with the patient’s illness. Non-surgical doctors are expected to make a correct diagnosis, i.e. determine what is wrong with the patient. The best treatments for most diagnoses have now been found. Diseases are treated with medicines according to fixed protocols and guidelines. The doctor then simply has to wait for the patient’s own healing powers to do their work. If the patient does not make it – and the diagnosis was correct – there is nothing you can do.
For surgeons, it is different. The success of an operation depends not only on the right diagnosis, a protocol and the patient’s own healing powers, but also on the surgeon’s personal involvement in the treatment. If the patient doesn’t make it and the diagnosis was correct, the surgeon still could have made an error. This means that surgeons, much more than non-surgical doctors, become personally involved in the patient’s illness. The surgeon is literally part of how the disease ends, happy or not.
This has led to a situation in which surgeons seek to establish what is wrong with a patient in a different way from non-surgical doctors. Because, as a surgeon, you have to answer to yourself for the fact that a patient’s recovery depends on your skill, you want to be absolutely sure what is wrong with him before you start. That need for certainty is far less urgent for non-surgical doctors. They can afford to be more distant from the beginning.
How do you decide what is wrong with a patient? In other words, make a diagnosis? Throughout the history of medicine, doctors have tried to answer that question. From the very beginning, they have always been confronted with the patient’s fear. Anyone feeling that their end is nigh, wants to know from the doctor how it will happen. Is there still any hope? How long have I got? Will I suffer pain? To answer these questions sensibly you have to recognise the patient’s problem. Doctors could do that better than anyone, because they had seen more diseases and disorders in their lives than other people. Once they knew what a patient had, they could make a prediction. Those two steps were known as diagnosis and prognosis, medical terms derived from the Greek word gnosis, meaning knowledge. Diagnosis, with the Greek preposition dia (through), means ‘seeing through’ or ‘insight into’. Prognosis, with the preposition pro (before), thus means a prediction or a prospect.
It was initially sufficient for a diagnosis to describe a disorder, even if you did not really know what was wrong. And you had no need of your hands to do that. If you saw a few pimples here and there, there was probably not much wrong, no matter what it was. But if the patient was covered from head to toe in badly smelling oozing pustules, that was something to be concerned about. In both cases, you could prescribe simple household remedies. If they didn’t help, they also did little harm.
For many centuries, the lack of understanding of the underlying causes of diseases was glossed over with a rather insubstantial story about four alleged bodily fluids, or humours: blood, mucus, yellow bile and black bile. The belief that a disease or complaint arose because the humours were out of balance was not, however, a good starting point for a surgeon. The only way for any of the four fluids to be replenished or reduced in quantity was by bloodletting, and that had very dubious effects. It was a typical remedy of non-surgical doctors.
The next step is not only to recognise and name the problem, but to find out what is causing it. Surgeons want to remove the causes, preferably with a knife. A diagnosis is important for the prognosis, while a cause is important for the treatment. Ileus, for example, is a general term for an obstruction in the passage of food and faeces through the intestines. It is a good example of a diagnosis dating from the time before we had any understanding of causes. If there is nothing you can do about it, the prognosis following a diagnosis of ileus is always bleak, no matter what the cause. The patient begins to vomit, is unable to defecate or break wind, develops a swollen abdomen, complains of severe cramps and, if the symptoms do not pass, will die. But if you can do something about it, you need to know not only that it is indeed ileus, but what has caused it. The intestine may be obstructed by a tumour or an inflammation, but also by a chicken bone. The diagnosis remains the same, but the surgical treatment is different in each case. The question asking what is wrong with a patient therefore embraces a number of other questions: what are the patient’s symptoms, what has caused them and how has that led to the disease?
Because a modern diagnosis entails much more than it
used to, the search for the answer has become more and more of a challenge, requiring highly developed skills. Medical doctors and surgeons work in the same way as detectives trying to solve a crime. A doctor trying to find out what is wrong with a patient resembles a detective searching for the perpetrator: identifying the cause of a disease is like looking for the motive for a crime, and establishing how a disease could have developed is reminiscent of following the tracks of the murderer and asking how he used the murder weapon. Just as all real detectives have their own style, doctors also solve mysteries in different ways.
The best writer of detective stories was undoubtedly Agatha Christie and by far the most brilliant character in her books was the detective Hercule Poirot. Poirot is an eloquent man, charming and intelligent, who unerringly solves every mystery that comes his way. But his creator also depicts him as something of an anti-hero. He is polite, but also vain and conceited; objective, but also arrogant and moody; inquisitive, but only willing to help if he finds the case interesting enough, and, though he speaks French, he is Belgian. The respectable, middle-aged detective is an eccentric, astute and prosperous man with a smartly waxed handlebar moustache, who time and time again – much to the killer’s chagrin, of course – happens to be in the vicinity when a murder takes place. In the Hercule Poirot stories, the plot unfolds according to a fixed formula. Poirot is surrounded by a company of well-defined characters at a more or less self-contained location – a remote country house, the Orient Express stranded somewhere in the snow, or a boat on the Nile. A murder takes place that must have been committed by someone in the group. As Poirot investigates the murder, it is clear that he knows more than he lets on. In the final chapter, he gathers everyone together in the drawing room or the saloon, to reveal the identity of the killer. He then addresses each of them individually. He explains that each one of them could have committed the murder. Each proves to have a hidden motive and no one has a cast-iron alibi. The butler had the key and access to the knife, the baroness had debts and could therefore make good use of the inheritance, the kitchen maid was jealous – nothing is too outrageous.
After having discussed the motives of each character, however, Poirot presents a counter-argument showing that he or she did not commit the murder. Until he comes to the final one – the killer. But that does not become clear until he has first been through all the others individually. In this way, the tension is built up until Poirot comes to the last remaining character and reveals the circumstances surrounding the horrific murder. His detailed accounts of the potential involvement of each character are so fascinating that we easily forget that the majority of the information he has gathered in fact has nothing to do with the case. After all, only the story about the real killer is relevant to solving the mystery.
This is exactly how an internist works. An internist is a non-surgical doctor, a medical specialist in General Internal Medicine (GIM) who concerns himself with diseases and treats them with medicine. A pulmonologist (who specialises in lung diseases), for example, is an internist, as is a gastroenterologist (digestive system), a cardiologist (heart), a nephrologist (kidneys) and an oncologist (cancer). Internists treat diabetes, cardiovascular diseases, blood diseases, inflammatory diseases, in fact all kinds of diseases, as long as an operation is not required. Like Hercule Poirot, an internist prefers to solve problems with a list. Poirot starts his analysis with the crime, asking ‘What happened?’ An internist starts with the patient’s complaint and asks ‘What is the problem?’ Then they both isolate the problem and restrict themselves to a well-defined summary of potential culprits. Poirot asks himself which of those present could have committed the murder, while an internist asks himself what might be the possible causes of the complaint. This is known in medicine as drawing up a differential diagnosis. Agatha Christie usually made it easy for Poirot to draw up his list by limiting the number of people at the scene of the crime, but internists too no longer have such a difficult time as formerly in drafting a differential diagnosis. Medicine has advanced so far in the past fifty years that, for most complaints and disorders, it is easy to look up a list of possible causes in a manual, in summary articles, in the medical-scientific literature or on the Internet. An internist thus has a list of differential diagnoses ready in no time.
Then it is time to analyse the evidence and clues. Poirot interrogates and investigates and, if necessary, calls others in to assist. An internist also questions his patient, not only about his current complaint, but also his general state of health, his medical history and family. He examines the patient, requests supplementary tests – blood tests, for example, or X-rays – and will, if necessary, ask the advice of a specialist in another area. Essentially, both Poirot and the internist focus on all potential perpetrators, and not only on the most likely ones.
Lastly, they have to exclude the unlikely culprits. They look closely at each of the candidates to see whether he or she could be guilty. They go through the whole list until there is only one left – the least unlikely. For the detective, it is the main suspect, for an internist, it is referred to as a ‘working diagnosis’. Exclusion on the basis of probability can lead to very surprising conclusions in the Poirot stories. In Murder on the Orient Express, for example, all those present prove to be guilty, while in Death on the Nile, the victim himself is the guilty party.
Surgeons do not understand this way of working. Their reasoning is usually more pragmatic and linear. Women may come from Venus and men from Mars, but it sometimes seems to surgeons that internists live in a completely different universe, far removed from all earthly logic. A surgeon can, for example, become very hot under the collar when an internist asks him to ‘exclude ileus’ in the case of a patient who no longer displays any symptoms and should actually be discharged, just because the radiologist happened to see what ‘could be interpreted as a possible ileus’ on the CT scan of the patient’s abdomen. For an internist, a result like this upsets his checklist and a suspected ileus must therefore be excluded by a surgeon. For a surgeon, however, that is nonsense. It is immediately clear that he should not operate on a patient with no symptoms simply on the grounds of a suspicion.
Conversely, an internist can be equally irritated by a surgeon who, while operating on a patient with suspected acute appendicitis, discovers that the small intestine is inflamed, rather than the appendix. Inflammation of the small intestine is not treated surgically, but with medicine. Yet the surgeon will stand by his decision to operate, because he found the patient very ill and suspected that he was suffering from life-threatening peritonitis. The internist could present arguments in return that throw doubt on the probability of appendicitis. For example, that the patient had been suffering from diarrhoea for a week before the inflammation occurred, which makes the diagnosis less likely.
What lies behind this mutual lack of understanding is a philosophical distinction between deduction and induction, two ways of discovering the truth through logic. Historically, the deductive is older than the inductive method, but both were replaced in the philosophy of science by the scientific method, developed by Karl Popper in 1934.
During the Middle Ages, it was widely believed that human knowledge had already reached its zenith in the golden age of classical antiquity. Doctors and surgeons therefore based their work uncritically on the wisdom of the Greek philosopher Aristotle and the Roman gladiator physician Galen, two men who, with hindsight, did not stand out as providing their theses with a solid foundation in fact. In the Renaissance, scientists once again dared to think critically and drew their own conclusions from general observations. That is deduction. A surgeon knows, as a general observation, that peritonitis can be fatal and that operating to remove the appendix presents a smaller risk. It is then logical, deductively speaking, to conduct an operation in a specific situation in which you suspect the patient may be suffering from appendicitis.
During the Enlightenment, a century later, the experiment developed as a serious basis for science. Conclu
sions were drawn from specific findings. That is induction. The more indications there are of a certain phenomenon, the more probable it is, and vice versa. A diagnosis of ileus is more probable if a CT scan shows possible indications of the disease, but less probable if the patient displays no symptoms and even less probable if a surgeon sees no reason to operate.
Then Karl Popper introduced the principle of falsifiability and the scientific method. He stated that the truth cannot be discovered. We can only develop a theory of the truth, and then only if we observe one crucial condition: the theory must be formulated in such a way that it can be refuted. This became the basis of all modern medical science. In daily clinical practice, the scientific method works as follows: a clear treatment plan is set in motion for a patient as quickly as possible, based on a working diagnosis. That working diagnosis is based on a falsifiable theory of reality. If the treatment does not have the desired effect, the working diagnosis must be critically reviewed. To reach a working diagnosis, however, induction and deduction remain at the patient’s bedside.
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Diagnosis
The investigation of a patient’s condition consists essentially of three elements. Firstly, the doctor will ask about the patient’s medical history, his current complaints (symptoms) and use of medication. This is known as the ‘anamnesis’, a Greek term meaning ‘from memory’. The doctor will also ask about diseases in the patient’s family and may ask other people about the patient (hetero-anamnesis). This might be, for example, the parents of a sick child or bystanders in the case of a traffic accident. The anamnesis is followed by a physical examination, during which the doctor feels, smells, looks, listens and measures. Looking is known as inspection, feeling as palpation, tapping as percussion, and listening with a stethoscope as auscultation. A doctor uses his index finger to palpate the rectum; this is known as palpatio per anum. He can test the reflexes of the pupils with a light and that of the tendons with a hammer. He can look in the ear with an otoscope and at the retina with a fundoscope. He can test different forms of feeling with a sharp pin or a tuning fork. A doctor’s nose is also an important instrument. You can sometimes determine the nature or composition of pus, wound infections or body fluids surprisingly accurately just by smell. Lastly, the doctor can request supplementary tests, such as a blood test, microscopic examination or medical imaging. Imaging can take the form of, for instance, an X-ray photograph, a contrast medium examination or a CT scan. Other examples of imaging include MRI (magnetic resonance imaging) scans, Doppler, ultrasound scans and duplex ultrasonography. Finally, disorders can sometimes be identified using radioactivity, via an isotope scan. This is known as scintigraphy.
Under the Knife Page 12