The irony is not lost on Dr. Brian Winn.

When his 7-year-old daughter was diagnosed with a brain tumor two years ago, Winn realized the cost of her treatment would max out his family’s limit on his small-group insurance. With cancer on their health record, the primary-care physician knew he would never qualify to buy another policy.

So his wife went to work for the state, which offers employees insurance — with no cap.

His daughter, Allison, came through her treatment and started fourth grade last week. Winn, meanwhile, is leaving his practice to join Kaiser Permanente.

He’s doing it, he said, because, as a private-practice physician, “I think our business model is broken.”

Health care in the United States is, arguably, the best in the world. The system for getting that health care to people who need it is not.

The system is inefficient, fragmented, expensive, inconsistent, and it currently excludes some 46 million people. It is, Winn and many others would say, broken.

Recognizing that is easy enough. Understanding what created this mess is a lot more complicated.

“The system got off track by a combination of forces,” said Dr. Randall Clark, a pediatric anesthesiologist and president of the Denver Medical Society.

Atop any list of those forces is skyrocketing costs.

Nationally, health care spending is expected to reach $2.5 trillion in 2009, according to the National Coalition on Health Care, which calls itself “rigorously nonpartisan.”

“We lead all industrialized nations in the amount we spend on health care,” said Rachel Nuzum, senior policy director for The Commonwealth Fund, a health care research and advocacy foundation.

“The trajectory of spending that we’re on is totally unsustainable,” Nuzum said.

Figuring out what drives cost increases is where the consensus starts to fracture.

But there is broad agreement about some contributors:

Incompatible records, communication systems

Often, a primary-care doctor’s computer can’t talk to a specialist’s computer, which can’t talk to a hospital’s. At best, that can mean a lot of time spent phoning and e-mailing records. At worst, it can mean needless repetition of expensive tests.

“We’re going to have to integrate ourselves to a greater degree, which will require some loss of autonomy, but the benefit will be well worth it,” Dr. Randall Clark said.

Dr. Brian Winn is finding that out.

Going to Kaiser means gaining an integrated system of care that fosters communication and consultation between primary-care doctors and specialists.

Kaiser Permanente’s system includes another difference: Doctors are paid salaries, not reimbursed for each patient visit. That illustrates one aspect of what many say is the Big Kahuna of contributors to the health system mess: how care is paid for.

Fragmentation

In 1949, when President Harry Truman pushed coverage for seniors, opponents branded him socialist, and the idea was shot down.

Sixteen years later, when President Lyndon Johnson signed the legislation, 19 million seniors enrolled. Now, the plan has more than 45 million enrolled, including 585,385 in Colorado.

Medicare is the biggest square in a patchwork quilt of government programs, including Medicaid, the Child Health Plan and the veterans system.

Each program has its own rules and procedures and, providers say, none pays enough for care to cover actual costs. Not that it’s easy to determine what “actual costs” are. Insurance companies negotiate rates with hospitals and doctors, and those vary enormously.

With 30 years’ perspective, Dr. Cecil Wilson, incoming AMA president, can say that it all adds up to medicine that’s a lot more complicated, a lot more bound by bureaucratic red tape — of both the government and the private insurance varieties.

“None of which, physicians would say, have added one iota to the quality of health care,” Wilson said.

How care is paid

“We would say the biggest driver of cost is the way we pay for health care,” said Rachel Nuzum of The Commonwealth Fund, a health care research and advocacy foundation.

Dr. Randall Clark, president of the Denver Medical Society, would second that: “I would say in general terms, what brought us to this point is a combination of factors, all related to the odd way we finance health care in this country,” he said.

Most insurance systems, including Medicare, reward doctors and hospitals for treating sick patients — a structure known as fee-for-service — but offer no incentives for keeping people healthy.

“If you have surgery in a hospital and you get an infection and stay two more days, the hospital makes a little more money,” Nuzum said. “We don’t think hospitals are willfully keeping people longer, but there are disincentives” for preventive care.

“Fee-for-service payments create incentives to provide high volume rather than high value — more, not better care,” wrote Bridges to Excellence chief executive François de Brantes and two co-authors in a recent New England Journal of Medicine article.

Bridges to Excellence is a nonprofit organization of doctors, employers and others in the medical industry dedicated to improving health care. That group and others are exploring variations in models that set payments for physicians, specialists and hospitals, based on evidence of what is best for treating a condition.

Health insurance as practiced in the United States was born during World War II.

In the 1930s, a few companies ventured into the health insurance business, but the public wasn’t too interested, partly because there wasn’t much in the way of expensive medical care. At that time, one study found, the average family spent $108 a year on health care.

During World War II, with thousands of working-age men and women off fighting, labor became so scarce that the government imposed wage freezes on remaining workers. With medicine advancing and its costs growing, employers competing for workers started offering health benefits.

And the link between employment and health insurance was forged.

That system works for a huge number of people, especially those who work for large companies, Nuzum said. But even those people and companies are feeling pinched by skyrocketing insurance costs.

Lawsuits

Aside from the costs of liability insurance, doctors order extra tests, perform procedures that may be unnecessary and take other costly steps to protect themselves from lawsuits.

“Defensive medicine adds $120 billion a year to the cost of health care,” said Dr. Cecil Wilson, an internist and the American Medical Association’s incoming president.

The uninsured

When people without insurance are turned away everywhere else, they turn up in emergency rooms, where, by law, they have to be seen. If they can’t pay for their care, everyone else does — through tax dollars or higher insurance rates.

Technological and scientific advances

Breakthroughs in technology, medications and therapies all add exponentially to the costs of health care.

A single MRI machine can set a hospital or clinic back anywhere from $400,000 to $2 million, according to one Chicago-area vendor. These days, it’s hard to find a large metropolitan hospital without one — or more.