OET Reading Part C
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Virtual reality in the management of pain
When headsets promising immersive pain relief first appeared at medical technology exhibitions, the response from pain specialists was largely sceptical. Most had seen a succession of over-promoted devices arrive and disappear and expected virtual reality (VR) to follow the same path. One senior anaesthetist dismissed the equipment as an expensive toy, observing that a paperback novel occupied a patient’s mind at a fraction of the cost. Two decades later, that verdict appears premature. VR is now supported by a larger body of evidence than several long-established analgesic techniques, and some of its early critics sit on the advisory boards of the companies that manufacture the headsets.
The earliest rigorous studies took place in burns units, arguably the most demanding setting available. Wound cleaning and dressing changes for severe burns are so painful that even high doses of opioid analgesics frequently fail to control the experience. A research group in Seattle developed SnowWorld, a virtual glacial canyon through which patients drifted while throwing snowballs at penguins, and recorded what happened when dressings were changed during play. Patients reported reductions of between a third and a half in their worst pain, in addition to the relief provided by their usual medication, and spent considerably less time thinking about their wounds. Such findings, however, rested entirely on self-report, which is precisely what a sceptic would expect an absorbing game to alter. What persuaded many doubters was neuroimaging: scans taken during VR sessions showed markedly reduced activity in the regions of the brain that process incoming pain signals. The effect, in other words, was not merely imagined.
The conventional explanation is attention. Pain is not a fixed quantity transmitted unchanged from injury to brain; the experience is constructed centrally, and attention is one of the mechanisms that shape it. A brain occupied with dodging virtual snowballs has, quite literally, reduced capacity to process the signal arriving from a wound. On this account, VR is essentially distraction with superior graphics. Some researchers, however, regard this as incomplete. Professor Daniel Okafor, who studies pain perception at a Canadian university, argues that immersion achieves something entertainment does not. ‘When the brain accepts a virtual body as its own, its map of the real body, including the painful part, can begin to be redrawn,’ he suggests. ‘No film or novel achieves that.’
That possibility is most relevant to chronic pain. Acute procedural pain is a relatively straightforward target: the painful event is brief, and any intervention that carries the patient through it has served its purpose. Persistent pain is another matter because it frequently continues in the absence of ongoing tissue damage and becomes entangled with fear, low mood and avoidance of movement. Thirty minutes in a glacial canyon offers little to a person who lives with pain day and night. The newer VR programs therefore resemble therapy rather than games: graded virtual movement for patients afraid to bend their backs; illusions that appear to shrink a swollen, painful limb; and structured courses teaching the neuroscience of pain from inside a headset. Regulators in the United States have now authorised one such eight-week program as a prescription treatment for chronic lower back pain.
Not all of those involved in the research share this enthusiasm. Dr Elena Marsh, who leads a VR research group in Manchester, argues that the principal weakness of the field lies in the quality of its evidence rather than in the underlying concept. ‘Most trials are small, short, and conducted by people who, like me, would prefer the technology to succeed. Nor can patients be unaware of whether they entered a virtual world, so expectation colours almost every result we have,’ she says. Her concern is not that VR is ineffective but that the commercial market is advancing faster than the science, with hundreds of wellness applications now sold on the strength of a small number of rigorous studies. Before any firm conclusions are drawn, she would like to see a single large, independent trial lasting a full year.
A balanced assessment therefore lies somewhere between the early dismissals and the promises of the marketing brochures. For severe, short-lived pain during medical procedures, VR has established itself as an adjunct to standard analgesia rather than a substitute for it, and any technique that reduces reliance on opioid medication merits serious attention. For chronic pain, it represents a promising form of therapy that still awaits the large, independent trials required to justify the claims made on its behalf. The charge that it offers nothing more than entertainment, at least, is difficult to sustain: entertainment has never been shown to quieten the brain’s processing of pain.
Noise on hospital wards
When patients are asked what they recall of a hospital admission, alongside anxiety and physical discomfort, a remarkable number mention something altogether more mundane: they could not sleep for the noise. Bin lids crashing, monitors sounding, staff conversing at the desk, the trolley with the squeaking wheel that always seems to pass at four in the morning. For many years, such complaints were regarded as the unavoidable background of a busy institution: regrettable, perhaps, but hardly a clinical concern. That assumption is now being questioned, as evidence accumulates that sleep is not a luxury the sick can forgo but part of the process by which they recover.
The measurements are striking. The World Health Organization advises that background noise in patient areas should not exceed 35 decibels, roughly the hush of a quiet library, with lower levels still recommended at night. Surveys of functioning wards regularly record averages above 55 decibels, with peaks (a dropped bedpan, an alarm) exceeding 85, the level at which employees in industry would be issued with hearing protection. In acoustic terms, a patient attempting to sleep on such a ward is resting beside a busy main road that periodically erupts into a pneumatic drill. Nor is waking the only concern. Dr Ingrid Sørensen, a sleep physiologist at a university hospital in Copenhagen, points out that much of the damage is invisible. ‘Sounds too quiet to wake a patient still produce measurable arousals. The sleeper is drawn again and again out of the deeper stages into lighter ones, usually with no memory of it,’ she explains.
Why should clinicians care? Because the consequences extend well beyond next-day tiredness. Poor sleep in hospital has been associated with delirium – the sudden, temporary confusion that prolongs admissions and, in older patients, predicts poorer recovery long after discharge. Sleep deprivation also raises blood pressure and stress hormones, weakens resistance to infection and interferes with the regulation of blood sugar, a particular hazard for the many inpatients who have diabetes. The effect is circular: patients are admitted because they are unwell, the ward disturbs the sleep their recovery requires, and the deterioration that follows extends the very stay that is costing them their rest. The ward, in short, works against the treatment delivered on it.
Equipment is the obvious suspect, and monitoring devices certainly generate an extraordinary number of alarms; a nurse in intensive care may deal with several hundred in a single shift. Yet studies in which wards were recorded overnight point elsewhere. Professor Marcus Bell, a nursing researcher in Melbourne whose team conducted one such study, found that the loudest and most disruptive sounds were seldom mechanical. ‘The peaks that actually woke patients were people: conversation, laughter and handover at full volume, often within a few metres of patients assumed to be asleep,’ he reports. The finding is uncomfortable because it locates the source of the disturbance in the very people employed to provide care. It is also encouraging, because behaviour, unlike the design of a cardiac monitor, can be modified without additional funding or equipment.
Several responses have proved reassuringly simple. Some wards have introduced ‘quiet time’, a protected period in the afternoon and again at night during which lighting is lowered, non-urgent tasks are deferred and voices are kept down. Those adopting the approach report measurable falls in sound levels together with improvements in patients’ own ratings of their sleep. Others distribute earplugs and eye masks, an intervention so inexpensive that it scarcely registers on a budget, yet one shown in trials to reduce the incidence of delirium. A few have appointed a ‘noise champion’ on each shift, whose sole responsibility is to notice when the ward has grown loud and to say so, a role that sounds trivial until one remembers how quickly a busy team ceases to hear itself. Acoustic panels, quieter flooring and soft-closing bins blunt the sharpest peaks. None of this is glamorous, and none of it will generate headlines, which may be precisely why the problem was neglected for so long: there is little professional glory in asking colleagues to lower their voices.
Perhaps the deepest obstacle is attitudinal. A busy, noisy ward can feel, to the team working on it, like a hard-working one, and quiet can be mistaken for idleness. Alarms, however wearing, resemble vigilance, and there is an understandable reluctance to silence anything that might occasionally matter. Yet the evidence increasingly indicates that an institution serious about recovery must treat the sound surrounding its patients as it treats hygiene or the safe administration of medicines: as a factor that shapes how well people get better rather than an afterthought. The patient kept awake by the squeaking trolley is not merely irritated. That patient is, in a small but genuine way, being prevented from recovering.
Duration of antibiotic treatment
Few pieces of medical advice are as widely known as the instruction to finish a course of antibiotics. It is printed on the label, repeated by the pharmacist, and it rests on a specific fear: that stopping early leaves survivors which have met the drug and learned to withstand it. In his Nobel lecture of 1945, the discoverer of penicillin described a man who dosed himself inadequately for a sore throat and passed a hardened strain to his wife, who died of it. The rule has been repeated ever since, though it has rarely been tested, and it has acquired the standing of common sense: to question it can seem irresponsible.
Over the past two decades it has nevertheless been questioned with growing confidence. For several of the most common bacterial infections, including pneumonia acquired outside hospital, skin infections and uncomplicated infections of the bladder, randomised trials have found that courses of three to five days perform as well as courses twice as long. An analysis published in a leading medical journal in 2017 concluded that the advice to complete the course had no basis in evidence and should be dropped. More remarkable is where the standard lengths came from. Prescribers everywhere have converged on the same figures: seven days, ten, fourteen. These are multiples of the week, a unit of time that has no meaning for bacteria, and nobody appears to have established that the tenth day of treatment achieves anything the fifth does not.
The explanation lies in where resistance actually arises. Dr Priya Raman, an infectious diseases physician at a teaching hospital in Leeds, points out that in most common infections the organism responsible does not have to be destroyed by the drug at all. ‘Antibiotics tip the balance and the immune system does the rest. What matters for resistance is not the comparatively small population at the site of infection but the trillions of bacteria living harmlessly in the gut, on the skin and in the throat, every one of which is exposed for every day the course continues,’ she explains. Those bystanders are under attack from nothing but the drug, and among them the resistant few flourish once their susceptible neighbours have been cleared. They may cause a quite different infection months later, pass their resistance to other species, or be carried to another patient altogether, and the person taking the tablets notices none of it. The price is paid elsewhere, and usually by someone the prescriber will never meet. The traditional advice, in other words, has the biology backwards.
None of this means that every course can be shortened. In tuberculosis, the bacteria multiply slowly, treatment lasts months, and a patient who stops early leaves survivors within the lungs that have encountered the drug and adapted to it. This is precisely what the traditional warning describes, and there it retains its full force. The same applies to infections of the heart valves, of bone and of the bloodstream, where weeks of treatment remain necessary. The lesson is not that shorter is always better but that the length of a course should be set by the infection being treated. For common infections, some hospitals now measure a blood marker that falls as a bacterial infection resolves and stop the antibiotic when it does; others have proposed a plainer instruction for patients: to stop when they feel better.
Not everyone who accepts the science accepts that instruction. Professor Tomas Lindqvist, a general practice researcher at a university in Gothenburg, does not dispute the trial evidence, but he objects to the message some have drawn from it. ‘Better is not the same as well,’ he says. ‘A patient with a kidney infection whose fever has settled may have a good deal of infection left. Tell people to stop when they feel better, and they will.’ His concern is not that shorter courses are wrong but that deciding when a course may end is a clinical judgement, and a slogan simple enough to fit on a label cannot carry it. He would rather prescribers set a length for each patient, shorter than before wherever the evidence allows, than hand the decision to the person least equipped to make it.
It is tempting to dismiss all this as a quarrel over a few tablets; it is nothing so small. The equally tempting response, a new instruction as short as the old one (stop when you feel better), would make the original mistake again: a single sentence, applied to every infection and every patient, in place of a judgement. The trouble with the traditional advice was never its content alone but its form, and any wording that brief can only be wrong in a new direction. What patients are owed instead is a length chosen for their particular infection, an honest account of why, and, where the evidence now says so, the admission that the old certainty was misplaced.
Screening and early detection
Ask people whether they would prefer to learn of a cancer now or in five years’ time and few hesitate. Early detection has become one of the least contested ideas in medicine, promoted by charities, endorsed by governments and confirmed by patients’ own intuition: a disease found sooner is a disease treated sooner, and a disease treated sooner is more often cured. Yet a growing body of research indicates that searching for disease in people who feel well can harm them, and does so with a regularity that the enthusiasm for screening seldom acknowledges. The problem has a name, overdiagnosis, and it describes the detection of abnormalities that would never have caused symptoms or death had they gone unnoticed.
The clearest illustration comes from thyroid cancer. From the late 1990s, one East Asian country offered an inexpensive ultrasound examination of the neck alongside its national screening program for other cancers. Over the following two decades the recorded incidence of thyroid cancer rose roughly fifteenfold. Deaths from the disease, however, did not fall at all. What changed was not the amount of lethal thyroid cancer but the amount of harmless thyroid cancer that was found and treated. Most of those diagnosed had the gland removed, leaving them dependent on replacement hormone for life, and a proportion suffered damage to the nerves of the voice or to the glands that regulate calcium. Thousands were made into cancer patients, and the death rate from the disease was exactly what it had been before.
This is possible because the body harbours far more disease than it ever declares. Autopsy studies of people who died of unrelated causes find small thyroid cancers in a substantial minority and prostate cancer in most men over seventy. Much of this disease grows so slowly that its host dies of something else first, and some of it does not grow at all. Undetected disease is a reservoir that screening never empties; a more sensitive test simply draws from deeper in it. Professor Anneke de Vries, an epidemiologist at a university in Utrecht, points out that finding disease earlier improves survival figures even when it saves no one. ‘Diagnose a cancer three years earlier and do nothing else, and survival from diagnosis lengthens by three years. The death has not moved; only the clock has,’ she says. Rising survival rates are therefore the first thing a screening program produces and the last thing that should be used to judge it.
The same pattern recurs wherever the search becomes more thorough. Blood-test screening for prostate cancer, in the largest trial to examine it, prevented about one death for every thirty men diagnosed, the remainder being treated, often with lasting effects on continence and sexual function, for tumours that would never have troubled them. Modern scanners, meanwhile, generate findings that nobody was looking for: a nodule in the lung of a patient scanned for abdominal pain, for instance. Each such finding starts a cascade of further imaging, biopsy and specialist review, with its anxiety, expense and occasional complications, and the great majority turn out to be nothing. The harm is spread thinly across many people, most of whom will never know that they were harmed, which is one reason it has taken so long to be recognised.
None of this persuades every clinician. Dr Rafael Ortega, a surgeon at a cancer centre in Lisbon, accepts that overdiagnosis is real but describes it as a statistician’s comfort. ‘I do not see a population. I see one woman with one nodule, and no test yet tells me which nodules will kill and which could safely have been ignored. Until one does, I am not going to gamble with her life to improve a national average,’ he says. He also observes that the argument is often made as though it applied to every program, when some, notably screening for cervical and bowel cancer, have demonstrably reduced deaths. His preferred response is not less detection but less reflex treatment: monitoring low-risk findings rather than operating on them, an approach that has already spread from prostate to thyroid cancer.
It would be easy to conclude that the earlier a disease is found the better, and to treat every objection as an argument for waiting until it is too late. But the intuition that opened this discussion contains a hidden step. Finding a disease early is of value only if finding it changes what happens next, and for a large and unknowable share of what screening uncovers, it changes nothing except the person’s identity, from someone who felt well to someone with a diagnosis. A diagnosis is not, in itself, a benefit. The proper measure of a screening program is not the number of cancers it detects but the number of deaths and the amount of suffering it prevents, set against the harm it does to the many who were never going to be ill.