This country's health care system, the system we are often told is the world's best, is in fact approaching "a critical condition," a new report contends.

If this warning is true -- and without doubt there is much truth in it -- what can we patients do to prepare ourselves?

Can we get ready for something less than the "best" of care, at least at times?

The answer is yes. We can learn to look out for ourselves in many ways. In fact, we need to do so already, for some of the "critical condition" is already here. ::

First, it is important to understand the problem. Two weeks ago the National Committee for Quality Care, a coalition of hospital systems and companies, issued the thoughtful report that sums up several of the recent conclusions of many observers.

Squeezed by tight payments by the government and insurers, hospitals are operating on lower profits, if any. They are sending patients home earlier, some too early. They are short of nurses, because the low pay scales are not attracting people to the profession. Many hospitals, hard pressed to stay in the black, are scrimping on all workers and new equipment.

Doctors are generally in good supply, but in the future they may not be. The high price of malpractice insurance has already driven many obstetricians and some neurosurgeons out of practice, creating shortages in some places. Hearing about the malpractice problem and other new pressures on physicians, fewer young persons are applying for medical school, especially fewer of the brightest.

Millions of Americans lack any or adequate health insurance and either get no care or, too often, receive second-class care at ill-funded public clinics or hospitals. Public hospitals are among hospitals threatened with curtailment or closing. There are now too many hospitals in much of the nation, but some of those forced to close may be the ones serving people who have nowhere else to turn.

The problem is not being seen as a whole, however, and few people or organizations, especially in the government, are considering the problem as a whole. ::

As an individual, you can do only so much about these national problems. But you can do a number of things for yourself, and it is now becoming urgent to do so.

Above all, find a good doctor. Or hang onto one if you have one. A capable, conscientious, caring doctor can be your guide to the best possible care under any circumstance. If you don't have such a doctor, look for one. Go to him or her for a physical as an introduction.

If you belong to a health plan -- an HMO (a health maintenance organization like Group Health or Kaiser) or an IPA (an independent practice association like M.D.-IPA, Capital Care or Physicians' Care) -- you still need to find a personal doctor within that organization. Many readers have reported finding excellent doctors (and some they didn't care for) in every area plan.

If you can't afford good insurance and use a public clinic, you can still try to get to know a doctor who really seems to care about you. Show you care about him or her, too, by your thanks or a note. This is a good way to help the doctor remember you as someone special.

Learn to look out for yourself. At the doctor's, at the hospital, at a clinic, ask questions about anything you don't really understand. But also, don't hold back information the doctor should know. Out of shyness or discomfort or embarrassment, many patients do.

Janet Hockman of Silver Spring, a satisfied member of Group Health Association (GHA), wrote me last year: "Each patient has considerable responsibility in taking charge of his or her personal health. Physicians can give their best diagnosis and treatment only if a patient communicates pertinent information regarding symptoms and then properly adheres to the instructions for treatment. Gone is the time when a patient just entered a doctor's office and simply stated, 'You tell me what's wrong, Doc.' " ::

About questions. Dr. Robert Rubin, former federal health official and principal author of the critical new report, says: "Many of the procedures performed by physicians are inappropriate . . . Many medical laboratories are not performing lifesaving tests accurately . . . There are far too many unnecessary hospitalizations or hospitalizations that are inappropriately long or inappropriately short."

When a physician or anyone else recommends any step or procedure that can affect your life -- and the most minor ones can do so -- ask: Why are you doing this? Are there any possible complications? What are the alternatives and should we be considering them?

Through life, learn all you can about yourself, your health and keeping healthy. We'll all be ill sometime. We can do much to improve the odds that it won't happen too soon. Regular exercise; a prudent, low-fat, low-cholesterol diet, light on meat and heavy on fruit and vegetables; shunning tobacco; using alcohol lightly -- all these can do more to keep you healthy than anything you can buy at the drugstore or vitamin-supplement counter.

Think carefully about your health coverage. Are you getting the best possible health insurance buy for your money? If you work for the federal government, or anyone else who gives you an annual choice of plans, review them to see where you might get the best coverage for the buck. Talk to fellow workers or a benefits manager who's familiar with various plans. For a family with young children and many doctor visits, an HMO or IPA is often a bargain.

If you're on Medicare, by all means buy Medicare Part B (doctor bill) coverage if you can afford it. You may also want to buy a supplementary policy, but look carefully at some that solicit or advertise widely. Some may cost you a lot every month for very little added coverage.

Try to stay out of the hospital. Go if you must, but first ask your doctor: Can I get the care I need without hospitalization? Should I? How about out-patient surgery? Home care?

If you must go, discuss your stay, and your problems, with your doctor. Ask: Will you be in every day? At around what time? Can I reach you on the phone if I need you?

Since hospitals are hard pressed now to (1) hire enough nurses and (2) stay in the black, you may get less service than you need. Be mentally prepared to look after yourself and your interests to the fullest extent possible, or try to get a family member or friend to come by daily to help -- and if necessary seek other assistance.

Almost every hospital now has a "patient representative" or ombudsman or such. Phone him or her from your bedside if you're unhappy with service or treatment.

For your own good and the health system's, face the fact that life someday must end. Someday you may want to tell a doctor, "If I'm only going to suffer or be a near vegetable, don't try to keep me alive."

Too few physicians, says Dr. Rubin, initiate this kind of conversation with their patients, no matter how sick the patients are. "We need to do a better job of this as physicians," he says, "but we all," physicians and patients, "have to think about the extent to which we'd want an all-out effort to save our lives under certain circumstances." ::

We are all potential patients, and we're all citizens too. This makes everyone's problems our problems.

When it comes to the nation's health problems, we need some hard thinking. Out of all pockets, public and private, this nation now spends more than 11 percent of its gross national product on health care.

Rubin, from 1981 to 1984 assistant secretary of health and human services for planning, predicts that we will spend more. He maintains that "there are limits in our ability as a society to pay more and provide more services. What is not clear is what those limits are. Regardless, we have not yet reached them." He says we need "a national commitment of government at all levels and of providers, payers and, most important, we the people" to see that our health system is adequately funded.

But he also says there are other national needs -- education, housing, defense -- and we must make choices. "It would be easy to conclude that all that is necessary to save our health care system is more money . . . This conclusion by itself would be wrong."

There is no limit to the amount that might be spent on medical care if everyone got every kind of care medical technology can provide. "Do we want more care," Rubin asks, "or less costs?"

Oregon legislators recently decided that the state should no longer pay for most costly organ transplants, operations costing between $150,000 and $250,000 each, and instead increase access to basic medical care for some 24,000 low-income people -- including 1,500 pregnant women -- each year.

As an almost immediate result, a 7-year-old boy with leukemia died before his family and supporters finished raising $60,000 to pay for a bone marrow transplant. The operation, which can cost up to $100,000, might or might not have saved him. The Oregon legislature may now reconsider its decision.

Right or wrong?