IELTS Academic Reading Practice Test 344

At the start of the eighteenth century, a Scot who wanted to become a physician had little choice but to travel abroad. Oxford and Cambridge offered medical degrees, but they were expensive and open only to members of the Church of England. Leiden, Padua and later Vienna drew students from every part of Europe, while Scottish medicine was taught largely by apprenticeship. Edinburgh had a university, founded in the sixteenth century, but it offered almost no teaching in medicine. Its college of physicians, established by royal charter in 1681, was a small body concerned mainly with the conduct of its own members.

The change began with a surgeon. In 1720 the town council, which managed the university and appointed its professors, gave Alexander Monro the chair of anatomy, and he held it for nearly four decades. Monro lectured with a thoroughness that attracted paying students from beyond the university. He also brought his family into the business: his son, Alexander Monro secundus, was appointed to assist him and in time succeeded him. The dynasty gave the school continuity, though it later acquired a reputation for resisting change.

Six years later the council took a larger step. In 1726 it appointed the first professors of medicine, among them John Rutherford, who became one of the school's most admired teachers. That year is generally taken as the foundation of the Edinburgh medical school. The arrangement was unusual. Rather than create a college with the power to award its own degrees, the council attached the new teachers to the existing university, which already possessed that right. Students could therefore qualify as doctors of medicine without ever visiting England.

Clinical teaching required patients. In 1729 a small hospital financed by public subscription opened in a converted house. In 1741 a much larger infirmary was completed on a site near the university. Here students followed the physicians and surgeons on their rounds and heard clinical lectures. In some cases they were allowed to examine patients themselves. The link between the lecture room and the ward was not unique to Edinburgh, but the scale on which it was organised was new, and visitors came to see how it was done.

Money shaped what was taught. Professors were not paid a salary by the university but collected fees directly from the students who enrolled in their classes. A lecturer who filled a hall could prosper; one who did not might earn very little. Competition encouraged energy and clear explanation, and it also encouraged professors to advertise their courses and to admit anyone who could pay, whatever his nationality or religion. The result was an education that students assembled for themselves from a menu of classes rather than a fixed programme imposed from above.

The absence of a religious test mattered. The English universities required membership of the Church of England, which excluded Roman Catholics and Protestant dissenters alike. In Edinburgh the only requirement was the ability to pay. Dissenting families from England and, increasingly, colonists from North America sent their sons to Scotland. Among the Americans who studied medicine there were John Morgan and William Shippen of Philadelphia, who later founded the first medical school in the colonies. Benjamin Rush took his degree in 1768 and later signed the Declaration of Independence.

Chemistry was transformed at Edinburgh by two men. William Cullen, who arrived in the mid-1750s, lectured on the subject, and in 1766 he was appointed to the chair of the theory of physic. His former pupil Joseph Black had already shown that the gas now called carbon dioxide was distinct from ordinary air. In the same year Black took Cullen's place as professor of chemistry, and he remained in the post for three decades. His lectures were admired for their precision, and his careful weighing of substances before and after a reaction became a model for the quantitative study of chemical change.

Students did not wait for their teachers to organise their intellectual life. In 1737 they founded a medical society of their own, which met to hear and debate papers written by its members and which survives today. Because it was run by students rather than professors, it gave them practice in argument and in presenting cases. Similar clubs followed, some short-lived and some lasting for generations.

By the 1780s Edinburgh was one of the most respected places in Europe to study medicine, and its graduates could be found in the armed forces, in colonial towns and in the growing cities of industrial Britain. Its attraction lay in the combination of a university degree, a hospital full of patients and a market in teaching that rewarded a good lecturer.

The school's dependence on dissection was also its weakness. Anatomy teaching needed a steady supply of bodies, and the only lawful source was the corpses of executed criminals, whose numbers were small. The shortage was met, illegally, by grave-robbing, and in 1828 it became a scandal when two men in Edinburgh, William Burke and William Hare, murdered sixteen people and sold the bodies for dissection. The outcry helped to produce the Anatomy Act of 1832, which allowed unclaimed bodies from workhouses to be used for teaching.

Asthma is a condition in which the airways of the lungs are inflamed and unusually sensitive, so that they narrow when triggered by exercise, cold air, pollen, dust or infection. The drugs used to treat it are almost always inhaled, because they act directly on the tissue that is causing the trouble. Relievers relax the muscle in the airway wall within minutes; preventers, taken daily, reduce the inflammation that makes the airways sensitive. A dose measured in micrograms can thus reach the lungs while very little enters the rest of the body, which keeps unwanted effects to a minimum. The difficulty lies in getting the drug past the body's defences, which are designed to keep particles out of the delicate air sacs. An inhaler is an answer to that problem.

The most familiar design, the pressurised metered-dose inhaler, is a small aerosol. At the top sits a metal canister, filled with the drug dissolved or suspended in a liquefied propellant. The canister is sealed by a metering valve, which contains a tiny chamber of fixed volume. The canister sits inside a plastic actuator, a moulded body with an opening at the top. At the base of the actuator is the mouthpiece, which the patient places between the lips. Pressing the canister down against the valve stem releases the contents of the chamber and allows it to refill, so that the next dose is ready. Some devices also carry a dose counter, a small window that shows how many puffs remain.

That measured volume is small, a few tens of microlitres. The propellant is a liquid only because it is under pressure. As it leaves the valve the pressure falls and it boils, tearing the liquid into a spray of droplets that leave the mouthpiece at high speed. The droplets are large by the standards of the lung, and the propellant continues to evaporate as they travel, so the cloud changes quickly in the first fractions of a second. What reaches the patient is therefore not a fixed mist but a stream of particles whose size and speed are still altering.

Only particles within a narrow range of sizes are useful. One larger than about five micrometres is likely to strike the back of the mouth or throat, where it does nothing for the lungs. With a steroid, it may also encourage a fungal infection. Very small particles, below about a micrometre, may be breathed in and out again without settling anywhere. With a pressurised inhaler used on its own, a large share of each dose, in many studies more than half, lands in the mouth and throat rather than in the lungs. Manufacturers therefore control the size of the particles in a dose as carefully as they control its weight.

The device also demands a skill that many patients lack. The canister must be pressed at the very start of a slow, deep breath, so that the spray is carried down with the air. Press too early and the drug hits the throat; press too late and it is left in the mouthpiece. Studies of technique repeatedly find that a substantial minority of adults, and an even larger proportion of children, use their inhalers incorrectly even after instruction. Instruction alone, several reviews conclude, is rarely enough. Breath-actuated devices, which fire when the patient begins to inhale, were developed to remove the problem.

The simplest remedy is a spacer, sometimes called a holding chamber: a tube, often the size of a large mug, which fits over the mouthpiece. The spray is fired into the chamber rather than into the mouth, and the patient then breathes in from it. In the extra second or two, the fastest droplets slow down and the propellant evaporates, so what is inhaled is a slower, finer cloud. Less of the drug is deposited in the mouth and throat, more reaches the lungs, and the risk of thrush from steroid inhalers falls. Spacers are especially valuable for children and for anyone who finds it hard to coordinate the two actions.

Not every inhaler uses a propellant. In a dry powder inhaler the drug is formulated as particles, often mixed with larger carrier particles of lactose. The patient's own inhalation then provides the energy to break up the powder and carry it into the lungs. These devices need no coordination of pressing and breathing and contain no propellant gas, but they require a sufficiently strong and sustained breath. A young child, or a patient in the middle of an attack, may not manage it. They are also smaller and easier to carry than a pressurised inhaler with a spacer.

Much remains uncertain. The proportion of a dose that reaches the lungs varies between patients and even between puffs, and computer models of deposition are hard to check against measurements in living people. Inhalers fitted with sensors that record when and how well they are used are now being tested, and early results suggest that they help patients improve their technique. A newer concern is environmental: the propellants used in pressurised inhalers are powerful greenhouse gases, and several health systems are urging patients whose lungs are strong enough to switch to dry powder devices.

Few questions in public health provoke such sharp disagreement as what to do about e-cigarettes. A device that heats a liquid containing nicotine and produces a vapour for the user to inhale, it has been on sale in Britain since the mid-2000s. It is now used by several million people, most of whom smoke or have smoked. Some specialists regard it as the most effective aid to quitting to appear in decades; others see it as a new route into nicotine addiction, promoted by companies with a long record of misleading the public. The argument is usually conducted as though one of these views must be wrong. In my view both contain part of the truth, and the policy that follows is more specific than either camp admits.

The case for relative safety rests on chemistry. A cigarette burns tobacco at a high temperature, producing tar, carbon monoxide and thousands of other substances, dozens of which are known to cause cancer. An e-cigarette does none of this: it heats a liquid, usually propylene glycol and glycerol with nicotine and flavourings, to a temperature well below the point of combustion. The user inhales a vapour rather than smoke, without the particles of tar that damage the lungs and without the carbon monoxide that strains the heart. Nicotine is not harmless, but it is not what kills smokers.

How much safer is it? In 2015 an independent review commissioned by Public Health England concluded that e-cigarettes were around 95 per cent less harmful than tobacco. The figure was attacked as guesswork, and the precision was certainly spurious, since no one can measure the long-term effects of a product that has been widely used for barely fifteen years. Later reviews reached similar conclusions in broader terms, agreeing that vaping is substantially less risky than smoking while warning that the evidence is thin. Regulators in several countries have accepted that judgement, even if they have drawn different conclusions about how easily e-cigarettes should be bought.

The case for quitting is stronger than it once was. Surveys of smokers who say they have given up with the help of an e-cigarette prove little, because people who succeed are more likely to be asked about it. Randomised trials are better, and one published in 2019 assigned nearly nine hundred smokers either to e-cigarettes or to conventional nicotine replacement, with both groups receiving counselling. After a year, those given e-cigarettes were roughly twice as likely to have stopped smoking. A Cochrane review of the trials has since reached the same conclusion, though its authors note that the devices tested are soon replaced by new models.

Against this stands the fear that vaping recruits new nicotine users. E-cigarettes are sold in sweet and fruity flavours and, until recently, in brightly coloured disposable devices that cost very little. Surveys in Britain and the United States have recorded steep rises in vaping among teenagers. The crucial question is whether this involves young people who would otherwise have smoked. The evidence is contested: some studies find that adolescents who vape are more likely to take up tobacco later, while others find that most regular vapers were already at risk of smoking.

The other fear is that the harm has been hidden. In 2019 hospitals in the United States reported a wave of severe lung injuries among vapers, and the episode was widely reported as proof that vaping damages the lungs. Investigation showed that most of the cases involved an illicit product containing vitamin E acetate, an additive found in cannabis oils sold on the black market rather than in nicotine e-cigarettes bought from shops. That correction received a fraction of the publicity given to the original alarm. It remains true, however, that the long-term effects of inhaling flavourings are unknown.

Policy has to hold these facts together. If e-cigarettes were banned, many vapers would return to tobacco, and a smaller number would buy unregulated products of unknown content. If they were left entirely to the market, companies would have every incentive to recruit adolescents, because a nicotine habit acquired at fifteen is worth more to them than one acquired at forty. The sensible middle course, it seems to me, is to keep e-cigarettes legal for adults and to tax them in proportion to the harm they cause. Advertising that appeals to children should be forbidden, and the nicotine content should be clearly labelled.

Two further lessons follow. The first is that the comparison that matters is not between vaping and nothing but between vaping and smoking. A policy that reduces vaping while leaving smoking untouched may do more harm than good, which is why the prescription-only model adopted in Australia, whatever its merits, cannot simply be copied. The second is that regulation must be accompanied by monitoring, so that rules can be changed as the evidence changes. I would rather defend a policy that is open to correction than one that is certain and wrong.