For whatever reason, many people seem to think that pets don't need any care beyond a certain age. I've had people decline vaccines, heartworm prevention, and other routine services because their pet is "too old". I've also had clients who don't want to do dental cleanings or other simple anesthetic procedures because their dog or cat was geriatric. It's interesting that different people have varying definitions of "old". The "magic age" might be 8, 10, 14, or just about anything. And perceiving their pet as old often has nothing to do with the pet's actual health. Just today I saw an 8 year-old boxer that the owner didn't want to do more than a rabies vaccine because he was too old. However, the dog was in excellent health and acted half his age.
Age is NOT a disease! Honestly, a pet's age is irrelevant to whether or not it should get certain procedures, or even survive anesthesia. The reason why there seems to be such concern is that historically older pets haven't done as well with surgeries or dental cleanings. But keep in mind that years ago we didn't use the same types of anesthetic drugs, didn't do as much monitoring, and didn't do pre-anesthetic blood testing routinely. As a pet ages, it has a higher likelyhood of stress on the organs, potentially leading to heart problems, liver disease, or kidney failure. However, a likelyhood of a problem does not equal a certainty. People and pets don't die from "old age", but from system or organ failure.
When I'm evaluating a pet, it's age is often a minor concern, especially for routine care. I may pay attention to it if I'm considering certain diseases or disorders that are more commonly in older pets. But otherwise I concentrate on evaluating the health. I have seen four month old puppies with fatal illnesses and 16 year old dogs that acted like they had no problems at all. I have done dental cleanings on 18-20 year old cats and dogs without any concerns or complications.
So keep all of this in mind when making decisions about your pet. Just because they are senior or geriatric doesn't mean that they should be prevented from receiving needed care. And if they're otherwise healthy, their age alone will not cause concerns for their survival. Look at the condition of their health, not how many birthdays they have had.