Simply put, tertiary prevention just delays death. Tertiary prevention is what happens when the emergency response system is activated or when one gets admitted to the hospital. It’s a bit of a stretch to call it prevention per se as the problem has already arisen. Let’s take fire as an example. Putting out matches completely or ensuring that a lit candle is well away from flammable curtains would be primary prevention of a fire disaster. A functioning smoke detector with a fresh battery in place is a secondary prevention measure. The fire has already started but the alarm alerts you at an early enough stage in the process to avert a calamity. Once the fire is in full blaze the fire department has to come with bells, lights, whistles, and large gauge hoses to prevent a catastrophe. Firefighters are employing tertiary “prevention” measures to save lives, or delay deaths (since everyone eventually dies).
Once someone has a disease we do our best to cure it. Many acute illnesses and injuries are easily treatable and complete healing is perfectly possible. Pneumonia, an infection of the lungs, is an example of an illness from which one can bounce back without any residual disability. A broken bone is another easy fix. Barring a full recovery we can treat people to prevent as much harm or discomfort from a disease as possible. Take high blood pressure as an illustration. If blood pressure is kept within a normal range damage to the kidneys, arteries, heart, eyes, and brain can be prevented. We can try to slow down the progression of a disease, in order to delay death. If someone has a traumatic injury we try to stop massive bleeding in order to postpone their demise, hopefully by a long time so they can return to living a full and joyful life. We can attempt to minimize the possibility of a disease causing other problems and complications. Someone with poor eyesight will be given prescription lenses to minimize the possibility of accidents. We may not think of prescription glasses as a preventive measure as they don’t stop the progression of the disease, but they do prevent the complications caused by having poor eyesight. We can try to decrease the interference a disease causes in the daily life of the person. Someone who has suffered a stroke and has residual disabilities will go through intensive rehabilitation efforts to improve their capacity to carry out their regular activities with as much ease as possible. In contrast to primary, secondary, and intermediary prevention, tertiary care is treatment of the problem with some preventive aspects to it. And that’s great too.