The federal government has an ultimate responsibility for seeing that an "adequate level" of health care is available to all citizens, a presidential ethics commmission said yesterday.

The 11-member panel, including eight Reagan appointees, warned that the government is falling far short of this goal.

"Inequities still exist in the financial protection people have against the cost of care, in the availability of health professionals and facilities, in the use of services and in the quality of care received," the prestigious commission said.

Hardest hit, it added, are the "working families of modest income, the very poor, members of racial and ethnic minorities and people who live in very rural and inner-city communities."

The report "represents the first attempt by a presidential commission to state a society's ethical obligation regarding access to health care, and to do so in a way that is realistic and achievable rather than through grandiose rhetoric about rights," said commission Chairman Morris Abram, a New York lawyer and former president of Brandeis University.

The commission avoids declaring that a "right to health care" exists, as labor groups and liberal Democrats have long asserted. Instead it emphasizes society's "moral obligation" to ensure access to health care, with the federal government stepping in if private, local and state efforts fail.

The panel also cautioned that it was not pushing for equal health care for all, saying that an "adequate level" means a "floor below which no one ought to fall, not a ceiling above which no one may rise." But the commission warned that the burden of current cost-cutting efforts "should not be borne mainly by those least able to afford it."

The report steers clear of specific recommendations as to how an adequate level of health care for all should be attained. At a news conference, Abram declined to comment on the impact of Reagan administration health-care budget cuts, saying only that we have "supplied the yardstick" by which policy-makers "can measure the impact of various alternative proposals."

The report does, however, tackle some current controversies. It is critical of "cost-sharing proposals" under which recipients would pay a larger share of Medicaid fees, an approach pushed by the Reagan administration, saying that although this is intended to "limit wasteful use" it is more likely to "discourage the use of valuable care."

It is more supportive of proposals--one is part of the administration's new budget plan--to make employes pay federal income tax on health insurance premiums paid by their employers. The commission said the current government tax subsidy is most beneficial to middle- and upper-income families and "contributes to inequities" in health care.

In describing inequities in health care, the report says the troubled economy has accelerated the problem. In addition to more than 20 million Americans who previously had no health insurance, another 11 million have lost employment-related insurance because of a job loss in the family, the commission said.

At the same time, the cost of health care continues to escalate faster than general inflation, it added.

The ability to pay is directly related to receipt of health care, the panel said, and people covered by health insurance visit the doctor far more frequently and spend twice as many days each year in the hospital as the uninsured.

Coverage under Medicaid, the major government program for those unable to pay, also is being reduced, even though about half of all poor Americans are already ineligible for aid, the panel noted. And there is pressure to cut expenditures under the Medicare hospital insurance trust fund for the elderly because the fund is in financial danger.

The findings of the President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research were sent to the President Reagan and the Congress in a 220-page report called "Securing Access to Health Care."

The three-year-old commission is scheduled to go out of business this week. Its current members include doctors, lawyers, theologians, and public-policy experts. Three were former president Carter's appointees. The rest were selected by Reagan last year.

Since issuing its first report on the determination of death in 1981, the panel has made recommendations on a range of topics important to American medicine, including research with human subjects, genetic engineering, screening for genetic problems, compensation for research injuries and informed consent. Its most recent recommendation was that terminally ill patients should have the right to forgo life-sustaining treatment.

Sen. Edward M. Kennedy (D-Mass.) is still pushing to extend the commission's life, an aide said Friday. But its sometimes controversial findings--and its backing by the liberal Kennedy--have drawn the wrath of some conservatives.The Reagan administration has made no effort to keep the commission alive.

The turnover in the commission membership last year reportedly led to sharp debate over the new report's wording but its conclusions remained fundamentally the same. One shift was to put greater stress on the positive side of medicine, including stronger emphasis that "focus on the problems of access ought not to obscure the great strengths of the American health care system."

The report was adopted by a vote of 10 to 1. The dissenter, Reagan appointee Dr. H. Thomas Ballantine Jr. of Harvard Medical School, complained that it was "negative" and "politicized to an unacceptable degree," implying the need for "further spending and increased control of health services by the federal government."