Complexity in medicine: some thoughts

I have been thinking recently about medicine and complexity, as a result of several conversations over many years. In particular, the Cynefin framework developed by Dave Snowden (see diagram below) seems a useful lens to use (this thought is not original to me – see among others, the articles “The Cynefin framework: applying an understanding of complexity to medicine” by Ben Gray and “Cynefin as reference framework to facilitate insight and decision-making in complex contexts of biomedical research” by Gerd Kemperman). I will also refer to two case studies from the book Five Patients by Michael Crichton, which is still quite relevant, in spite of being written in 1969.

The Cynefin framework developed by Dave Snowden. The central dark area is that of Disorder/Confusion, where it is not clear which of the four quadrants apply (image: Dave Snowden).

The Cynefin framework divides problems into four quadrants: Obvious, Complicated, Complex, and Chaotic. In addition, the domain of Disorder/Confusion reflects problems where there is no clarity about which of the other domains apply. In medicine, this reflects cases where multiple factors are at work – potentially, multiple chronic conditions as well as one or more acute ones. These conditions can exist in all four quadrants. Ben Gray gives the example of a child with a broken arm linked to both a vitamin deficiency and an abusive home environment. Several quite different interventions may be required.

The Obvious Quadrant

The quadrant of the Obvious applies to conditions with clear cause and effect, where there is a single right answer. According to Dave Snowden, the appropriate response is to sense what is going on, categorise the situation as one on a standard list, and then to respond in the way that people have been trained to do. This response may be trivial (a band-aid, say), or it may involve enormous professional skill. In medicine, much of nursing falls in this quadrant, as does much of surgery.

Michael Crichton’s Five Patients discuses the case of Peter Luchesi, a man admitted to Massachusetts General Hospital during 1969 with a crushed arm and nearly severed hand, as the result of an industrial accident:

Three inches above the left wrist the forearm had been mashed. Bones stuck out at all angles; reddish areas of muscle with silver fascial coats were exposed in many places. The entire arm about the injury was badly swollen, but the hand was still normal size, although it looked shrunken and atrophic in comparison. The color of the hand was deep blue-gray.

Carefully, Appel picked up the hand, which flopped loosely at the wrist. He checked pulses and found none below the elbow. He touched the fingers of the hand with a pin and asked if Luchesi could feel it; results were confusing, but there appeared to be some loss of sensation. He asked if the patient could move any of his fingers; he could not.

Meanwhile, the orthopedic resident, Dr. Robert Hussey, arrived and examined the hand. He concluded that both bones in the forearm, the radius and ulna, were broken and suggested the hand be elevated; he proceeded to do this.

Outside the door to the room, one of the admitting men stopped Appel. ‘Are you going to take it, or try to keep it?’

‘Hell, we’re going to keep it,’ Appel said. ‘That’s a good hand.’

Once the surgeons had sensed the problem and categorised it as an arm reconstruction, a team of three surgeons, two nurses, and an anaesthetist (all highly trained in their respective fields) then spent more than 6 hours in the operating theatre, repairing bone, tendons, and blood vessels. Certainly not trivial, but a case of professionals doing what they were trained to do.

The Complicated Quadrant

Public Domain image

The Complicated quadrant is the realm of diagnosis. Information is collected – in medicine, that generally means patient history, blood tests, scans, etc. – and is then subjected to analysis. This identifies the nature of the problem (in an ideal world, at least), which in turn indicates the appropriate response.

Diagnosis by physicians typically searches for the cause of an illness, while diagnosis by nurses typically focuses on severity. This reflects differences in the responses that physicians and nurses have been trained to provide (the triage officer in a modern hospital is typically a nurse).

Decades of work have gone into automating the diagnosis process – initially using statistical analysis, later using expert systems, and most recently using machine learning. At present, the tool of choice is still the human brain.

In general, modern medicine excels when it operates in the Obvious and Complicated quadrants.

The Complex Quadrant

The Complex quadrant is the realm of interactions. It is inherently very difficult to deal with, and cause and effect are difficult to disentangle. The paradigm of information collection and analysis fails, because each probe of the system changes it in some way. The best approach is a sequence of experiments, following each probe with a response that seems reasonable, and hoping to find an underlying pattern or a treatment that works. Michael Crichton provides this example:

Until his admission, John O’Connor, a fifty-year-old railroad dispatcher from Charlestown, was in perfect health. He had never been sick a day in his life.

On the morning of his admission, he awoke early, complaining of vague abdominal pain. He vomited once, bringing up clear material, and had some diarrhea. He went to see his family doctor, who said that he had no fever and his white cell count was normal. He told Mr. O’Connor that it was probably gastroenteritis, and advised him to rest and take paregoric to settle his stomach.

In the afternoon, Mr. O’Connor began to feel warm. He then had two shaking chills. His wife suggested he call his doctor once again, but when Mr. O’Connor went to the phone, he collapsed. At 5 p.m. his wife brought him to the MGH emergency ward, where he was noted to have a temperature of 108 °F [42 °C] and a white count of 37,000 (normal count: 5,000–10,000).

The patient was wildly delirious; it required ten people to hold him down as he thrashed about. He spoke only nonsense words and groans, and did not respond to his name. …

One difficulty here was that John O’Connor could not speak, and so could not provide information about where he felt pain. He appeared to suffer from septicaemia (blood poisoning) due to a bacterial infection in his gall bladder, urinary tract, GI tract, pericardium, lungs, or some other organ. Antibiotics were given almost immediately, to save his life. These eliminated the bacteria from his blood, but did not tackle the root infection. They also made it difficult to identify the bacteria involved, or to locate the root infection, thus hampering any kind of targeted response. In the end (after 30 days in hospital!) John O’Connor was cured, but the hospital never did locate the original root infection.

Similar problems occur with infants (Michael Crichton notes that “Classically, the fever of unknown origin is a pediatric problem, and classically it is a problem for the same reasons it was a problem with Mr. O’Connor—the patient cannot tell you how he feels or what hurts”). As Kemperman notes, medical treatment of the elderly often also falls in the Complex domain, with multiple interacting chronic conditions, and multiple interacting drug treatments. Medical treatment of mental illness is also Complex, as the brain adapts to one treatment regimen, and the doctor must experiment to find another that stabilises the patient.

Similarly Complex is the day-to-day maintenance of wellness (see the Food and Wellness section below) which often falls outside of mainstream medicine.

The Chaotic Quadrant

The Chaotic quadrant is even more difficult than the Complex one. Things are changing so rapidly that information collection and experimentation are impossible. The only possible response is a dance of acting and reacting, attempting to stabilise the situation enough that it moves from Chaotic to Complex. Emergency medicine generally falls in this quadrant – immediate responses are necessary to stop the patient dying. In the airline industry, the ultimate (and extremely rare) nightmare of total engine failure shortly after takeoff (as in US Airways Flight 1549) sits here too – each second of delay sees gravity take its toll.

Success in the Chaotic domain requires considerable experience. In cases where the problem is a rare one, this experience must be created synthetically using simulation-based training.

Food and Wellness

Michael Crichton notes that “The hospital is oriented toward curative treatment of established disease at an advanced or critical stage. Increasingly, the hospital population tends to consist of patients with more and more acute illnesses, until even cancer must accept a somewhat secondary position.” There is, however, a need for managing the Complex space of minor variations from wellness, using low-impact forms of treatment, such as variations in diet. Some sections of this field are reasonably well understood, including:

Traditional culture often addresses this space as well. For example, Chinese culture classifies foods as Yin (cooling) or Yang (heaty) – although there is little formal evidence on the validity of this classification.

There remain many unknowns, however, and responses to food are highly individual anyway. There may be a place here for electronic apps that record daily food intake, medicine doses, activities, etc., along with a subjective wellness rating. Time series analysis may be able to find patterns in such data – for example, I might have an increased chance of a migraine two days after eating fish. Once identified, such patterns suggest obvious changes in one’s diet or daily schedule. Other techniques for managing this Complex healthcare space are also urgently needed.


Origin by Dan Brown: a book review

Origin by Dan Brown (2017)

I recently read Origin, the latest Dan Brown novel. Just about every Dan Brown novel covers topics dear to my heart, such as cryptography, computer simulation, the theory of computation, and artificial intelligence – but also the history of science, the history of Christianity, Dante, and Galileo. Dan Brown routinely promises an accurate depiction of these background topics (in this latest novel, he says “All art, architecture, locations, science, and religious organizations in this novel are real”). However (as I also pointed out for his Angels & Demons), the reality of his novels doesn’t quite live up to this claim. To pick just three examples, Yves Klein did not invent the pigment in International Klein Blue; “Pope Innocent XIV” was an Argentinian antipope, not a Spanish one; and it is not suprising when computer simulations produce results reflecting the assumptions built into their design.

Gaudí’s la Sagrada Família (image credit) plays a major part in the novel. It has been on my bucket list for decades. It still is.

Even as a work of pure fiction, Origin still disappoints. As with Dan Brown’s previous novels, the constant appearance of crazed gunmen doesn’t make up for the plot weaknesses. And a major theme of the novel is artificial intelligence – now, I don’t object to this being portrayed far in advance of current technology (that’s not uncommon in fiction), but the theme of artificial intelligence has been handled far better by (among others) Robert A. Heinlein, Arthur C. Clarke/Stanley Kubrick, Michael Crichton, and Peter F. Hamilton. I also found the book’s ending profoundly anticlimactic. However, if you’re a fan of Dan Brown novels, you’ll probably like this one too.

For other reviews, see The Week (“Dan Brown is a very bad writer”), The National (“The idea that a computer simulation would fundamentally destroy the faith of billions in their religions is so utterly, cluelessly juvenile that it seems right at home in a Brown novel”), and The Stream (“It’s sci-fi done by someone who knows nothing about sci-fi”).

Origin by Dan Brown: 2 stars

The Crucible of Time: a book review

The Crucible of Time by John Brunner (1983)

I recently re-read The Crucible of Time by science fiction author John Brunner (1934–1995). It is one of the last great triumphant-rise-of-human-progress novels where, in spite of all kinds of natural disasters, the inhabitants of a planet drag themselves through thousands of years of scientific development in order to escape their doomed planet (around the 80’s, science fiction became darker and more dystopian, as indeed, many of Brunner’s other novels are). What makes this novel stand out from a rather dull subgenre is that the characters are not human at all, but are some kind of mollusc. When you can get your readers to identify emotionally with a sort of intelligent slug or squid, then you’ve got serious writing talent: “‘But – !’ She sank back, at a loss. For the first time it was possible to see how pretty she was, her torso sleek and sturdy, her claws and mandibles as delicate as a flyet’s. Her maw still crowded, she went on, ‘But I always thought you and Professor Wam were enemies! When I heard you were giving a lecture and she had agreed to reply to you, I couldn’t really believe it, but I decided I had to be present, because you’re both on the other side from my parents. They are crazy, aren’t they? Please tell me they’re crazy! And then explain how you two can be acting like friends right here and now! I mean,’ she concluded beseechingly, ‘you don’t smell like enemies to each other!’

At one level, The Crucible of Time is a strange tirade against religion, having set up a universe in which the religious leaders are, by construction, dangerously wrong. This gives Brunner’s characters some more immediate opponents than the impending disaster itself, but these opponents seem a little too much like cardboard cut-outs most of the time. I was left somewhat confused as to why the universe of the novel contained religion at all. An evolutionary argument was implied, but it didn’t seem to make sense.

The novel (or rather, collection of linked stories) does have some fascinating descriptions of a civilisation that’s built mostly, but not entirely, on biology – in contrast to ours, which is built mostly, but not entirely, on physics. Brunner avoids tedious descriptions by giving animals names that suggest English equivalents. The alien equivalent of a domesticated camel is a drom, for example. The large domesticated water-creatures that perform the function of ships are barqs, briqs, and junqs: “‘Correct! Well, if a mindless plant can find a way to spread beyond its isolated patch, why shouldn’t we? Did it ever strike you that there must have been a first person who pithed a barq or briq, just as there was certainly a first who tamed a junq? Then, folk were confined to continents or islands, and had to trudge wearily from place to place unless they had a drom—and someone, equally, must have been first to ride a drom!’

In a similar vein are words like laq, sourgas, and stumpium (named after the planet Stumpalong). Checking Internet reviews, this aspect of the novel seems to be both loved and hated.

But I consider this novel to be one of the great science fiction classics; it’s well worth a read. See here for a more detailed review and plot summary.

The Crucible of Time by John Brunner: 3½ stars

The Invention of Clouds: a book review

The Invention of Clouds: How an Amateur Meteorologist Forged the Language of the Skies by Richard Hamblyn (2001)

I recently read The Invention of Clouds by Richard Hamblyn, who also wrote Terra (which I reviewed some years ago). The present volume focuses on the Quaker pharmacist Luke Howard, who produced a taxonomy of clouds in 1802. Essentially the same classification is still used today (but not, as Hamblyn points out, without considerable debate during the 1800s):

Although the focus is on Howard’s work and life, Hamblyn in fact provides a brief history of meteorology (or at least of the study of clouds), and there is a chapter on the Beaufort scale. Contemporary literature referred to includes:

Google Ngrams plot for three of the cloud types (with and without hyphens). The words “cirrostratus” and “cirrocumulus” first appear in reprintings of Howard’s pioneering essay, while the word “cumulonimbus” is introduced around 1887. There is a renewed spike of interest in cloud types beginning in the early 1940’s.

The Invention of Clouds also has some interesting comments on clouds in art and on how to get an education at a time when the two English universities banned non-Anglicans from attending. However, the book does have a few small errors. For example, cloud droplets are not “a mere millionth of a millimetre across,” but in the range 0.005 to 0.05 mm. However, that does not stop the book from being both enjoyable and informative (although I did wish for colour images). See also this review from the NY Times.

The Invention of Clouds by Richard Hamblyn: 3½ stars

Crosstalk: a book review

Crosstalk by Connie Willis (2016)

I recently read, with great enjoyment, the science-fiction romantic comedy Crosstalk by Connie Willis. This novel is reminiscent of her previous books Bellwether and Passage. Like Bellwether, it is set in a high-tech company (this time, a mobile-phone company), and has the fast-paced craziness of Howard Hawks movies such as Bringing Up Baby or His Girl Friday. Like Passage, it has a hospital staircase scene, and explores themes relating to neuroscience and parapsychology.

The social commentary in Crosstalk focuses mainly on social media and the dangers of too much communication. The novel begins: “By the time Briddey pulled into the parking garage at Commspan, there were forty-two text messages on her phone. The first one was from Suki Parker—of course—and the next four were from Jill Quincy, all saying some variant of ‘Dying to hear what happened.’ Suki’s said, ‘Heard rumor Trent Worth took you to Iridium!???’ Of course you did, Briddey thought. Suki was Commspan’s very own Gossip Girl. And that meant by now the whole company knew it. …

To say too much more than that would involve spoilers. The Guardian also liked the novel, but the LA Times did not. I’m giving it four stars.

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Crosstalk by Connie Willis: 4 stars

Eureka! – a book review

Eureka!: The Birth of Science by Andrew Gregory

I recently read Eureka!: The Birth of Science by Andrew Gregory. The book deals with a topic that has long fascinated me – the birth of science. In a previous post I argued that this took place in the 12th century, the age of cathedrals. Gregory takes the view that it happened with the ancient Greeks, and sees Aristotle and Archimedes as among science’s pioneers. He gives a brief defence of this thesis, and provides a quick summary of Greek scientific thought.

Aristotle and Archimedes

I found this book rather short for the subject (177 pages, including bibliography), was disappointed at the lack of endnotes, and found some annoying errors (the Greeks did not consider the universe small, for example – Archimedes took it to be 2 light-years across). But the big unanswered question is: what went wrong? Gregory includes a list of key people at the back of the book, and if you turn that list into a bar chart, you can see that Greek science basically fell off a cliff around 200 BC.

In a brief two-page section towards the end, Gregory suggests that Christianity was somehow responsible for the decline of Greek science, but that simply makes no sense. Was it instead Roman conquest, beginning around 280 BC? Was it the growing separation of aristocratic philosophy from plebeian technology? Was it the replacement of original science by encyclopaedic systematisation (such as that of Pliny)? It would have been nice to have those questions answered.

Goodreads gives this book 3.4 stars; I was rather less enthusiastic.

Eureka!: The Birth of Science by Andrew Gregory: 2 stars

True Stories – a book review

True Stories: And Other Essays by Francis Spufford

I recently finished True Stories: And Other Essays by Francis Spufford – a collection of real gems by a man who can truly write. A selection of essays, book reviews, and other non-fiction works, this book is divided into the thematic sections “Cold,” “Red,” “Sacred,” “Technical,” and “Printed.” The section “Technical,” for example, includes a piece on British engineering, together with a wide-ranging essay on Babbage’s “Difference Engine No. 2,” reconstructed by the Science Museum, London. Babbage never completed this device, of course, and perhaps could not have done so, given the technological limitations of his time. This leads Spufford into a general reflection on counterfactual history, drawing also on the novel The Difference Engine.

The section “Cold” includes several pieces on polar exploration, such as an introduction written for The Worst Journey in the World (a memoir of the 1910–1913 British Antarctic Expedition), and a piece on Ernest Shackleton. I’ve been fascinated by polar exploration since childhood, so I found these particularly interesting.

Grotto in an iceberg, photographed during the 1910–1913 British Antarctic Expedition (image credit)

The section “Red” deals largely with the former Soviet Union. It includes an explanation of Spufford’s fictional documentary book Red Plenty, and the essay “The Soviet Moment,” which is still online at The Guardian: “It was not the revolutionary country people were thinking of, all red flags and fiery speechmaking, pictured through the iconography of Eisenstein movies; not the Stalinesque Soviet Union of mass mobilisation and mass terror and austere totalitarian fervour. This was, all of a sudden, a frowning but managerial kind of a place, a civil and technological kind of a place, all labs and skyscrapers, which was doing the same kind of things as the west but threatened – while the moment lasted – to be doing them better. American colleges worried that they weren’t turning out engineers in the USSR’s amazing numbers. Bouts of anguished soul-searching filled the op-ed pages of European and American newspapers, as columnists asked how a free society could hope to match the steely strategic determination of the prospering, successful Soviet Union. … The loudest and most important lesson of the Soviet experience should always be: don’t ever do this again. Children, don’t try this at home. … Yet we’d better remember to sympathise with the underlying vision that drove this disastrous history, because it is basically our own.

The section “Sacred,” obviously, deals with religion (Spufford is an English Anglican). It includes a critique of Richard Dawkins, a reflection on C. S. Lewis, and a record of travels in Iran. The New Humanist still has online the essay beginning “Allow me to annoy you with the prospect of mutual respect between believers and atheists. … No? No. Because the idea of atheism as an extravagant faith-driven deviation from the null case goes against one of the most cherished elements in the self-image of polemical unbelief: that atheism is somehow scientific, that it is to be adopted as the counterpart in the realm of meaning to the caution and rigour of the scientific method.

Spufford visited the Sheikh Lotfollah Mosque in Isfahan, Iran (image credit)

Finally, the section “Printed” includes miscellaneous introductions and book reviews, including an introduction to The Jungle Book, a review of the Mars trilogy, and an obituary of Iain M. Banks. This last section reflects Spufford’s wide-ranging interests in technology, exploration, and imagination. For me, at least, it established a connection of sorts with the author: we read the same things; we are brothers.

The last section of True Stories includes a review of the Mars trilogy by Kim Stanley Robinson

See The New York Times and the New York Journal of Books for other reviews of True Stories. I’m giving it four stars overall, although several of the individual essays deserve five. This book was a delight to read.

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True Stories: And Other Essays by Francis Spufford: 4 stars