NEW DELHI: Last month, a video went viral claiming doctors in Madrid were removing people aged over 65 from ventilators , to save lives of younger Covid-19 patients. It turned out to be fake news, but a situation in which doctors have to choose between patients is not unlikely now, as the number of Covid-19 cases continues to rise.All over the world, hospitals are under tremendous strain. There aren’t enough ICU beds and ventilators to save every critical patient. On a routine day, who gets attention first depends on the severity of their condition. You have an accident victim with signs of internal bleeding, and another with a fractured arm: the haemorrhaging patient comes first.The corona pandemic has made the ordinary rules of ‘ triage ’ or patient classification meaningless. Now, there is a stream of critically ill patients. Say, you are a doctor with one remaining ventilator and three new arrivals. Whom do you save? Whom do you let die?It’s an ethical dilemma that no doctor wants thrust upon them. That’s why general rules to deal with such situations have existed for a long time. While military hospitals often need to make use of them, this is the first global medical crisis in a long time that’s forced hospitals to dust their manuals, and medical ethicists to work on improving the existing guidance. They know that the allocation of equipment and care to patients will always be contentious, but they need to make it clear, ethical and equitable as far as possible.Take the situation above: one hospital may decide to save the youngest of the three patients, arguing that they have had the least time to live, and an early death would be most unfair to them. This is a perfectly valid philosophical position, but another hospital might decide to save whoever has the best chance of survival. In Germany , for instance, triage does not take a patient’s age into consideration.What if one of the patients is 19, another is 40 but in good health otherwise, and the most likely to survive, and the third is a nurse, whose recovery could help many other patients live. This time, many hospitals would choose to save the nurse for society’s good.That’s the main difference between triage in an emergency (accident victims) and a crisis (stream of Covid-19 cases). During an emergency, doctors aim to do their best for the patient before them, but in a crisis, the goal shifts to doing the greatest good for the greatest number. And this ordinarily means taking steps to ensure that the greatest number of patients survive.If you have advanced liver disease or a serious heart condition, saving you becomes less important because you might occupy a bed for three weeks and still not make it while a fitter patient would. Doctors call it ‘success-oriented’ allocation of resources. It means, in a crisis, taking someone off the ventilator is not only justifiable but ‘just’ if the next patient has better odds of survival. There’ll never be a perfect algorithm for triage. Will you save a 30-yearold mother who has Covid-19 and breast cancer, or her bachelor brother, aged 40, who has only Covid-19? Will you save 10 octogenarians (higher success rate) or five teens (more years to live)? Which choices serve society best?Sometimes, even ethics and philosophy throw up their hands. Then, it’s time for a lottery.