Two years ago the Social Security Administration told Congress that the goverment's program to aid chronic kidney patients would cost $1 billion by 1984.

Last April, Congress got a new estimate: $1.9 billion by 1982 and $6.3 billion by 1992.

When Congress enacted the program in 1972 to pay for long-term care and kidney transplants for virtually anyone under Medicare, the reasons seemed compelling enough. the technology was available who otherwise would die for lack of money to gain access to life-saving machinery.

No one is arguing that the federal government now should abandon the effort. But the soaring cost of the program - enacted after an hour's debate in the Senate - has brought a sober reappraisal of it in Congress.

According to estimates from the Department of Health, Education and Welfare, 34,000 persons are now being treated at a cost of $500 million.

From a financial perspective, however, the program may be suffering from its own success. It also is another example of galloping inflation in medical care which, if not checked, policymakers warn, will pre-empt funds needed for other social programs.

An estimated 20 per cent of kidney patients are dialyzed on machines in their home, with most of the remainder going two or three times a week to dialysis centers for treatment. The procedure removes waste materials from the blood.

The cost of dialysis in the home, according to various estimates, is one-third to one half of the $20,000 to $25,000 annual cost of doing it in centers. The overhead in centers is higher because of the personnel cost and physician fees.

In 1972, about 40 per cent of he kidney patients were dialyzed in their homes. As the number of patients on dislysis has grown, the percentage receiving home treatmet has shrunk.

Why the percentage of home dialyzed patients is dropping is not clear. One theory is that with Medicare paying the bill, more centers have opened, and doctors have become less selective about whom theyplace on dialysis. Thus, older patients, who are not suitable for home dialysis and who would have not has been given precious time in centers five years ago, can now be accomodated more easily.

Re. Charles A. Vanik (D-Ohio) suggested during hearings last month that the present system, under which thesame physician who collects a fee for treating a patient also decides whether the patient should be sent home to treat himself, "is probably the most massive case of potential conflict of interest in the medical community today."

Vanik, with Rep. Dan Rostenkowskl (D-III.), has introduced a bill, which a House committee began marking up yesterday, designed to move a large number of kidney dialysis patient out of clinics and into their own homes for treatment. But the bill raises other problems, including charges that Congress would be intefering in the doctor-patient relationship.

Under the bill, 40 per cent of the patients on dialysis would be required to receive care at home or perform self-care in a center by Oct. 1, 1978, with a target of 50 per cent by 1980.

Health, Education and Welfare Deputy Assistant Secretary for legislation Grant Spaeth expressed concern last month during a hearing before the House Ways and Means health subcommittee that no agreements existed between HEW, doctors and Congress as to what the target figure should be.

Dr. Michael Goran, director of the Social Security Administration's Bureau of Quality Assurance, said that the basic issue is "who makes the final determination as to choice of treatment. Currently and historically this has always been with the patient and his physician."

But Dr. Belding Scribner, one of the pioneers in the field of kidney dialysis, said that "What started in 1960 as a noble experiment gradually has has degenerated into a highly controversial billion-dollar riddled with cost over-runs and enormous profiteering."

One of the most outspoken opponents of the bill during the hearings was Dr. Eugene Schupak, president of National Medicare Care, Inc., a firm that operated 68 centers in 19 states and Puerto Rico and did $128 million worth of business in 1976, treating and selling medical supplies for dialysis patients.

"The notion" Schupak said, "that since Congress is paying the bill, it can mandate the particular form of therapy to be rendered, if carried to its logical conclusion, would permit Congress to dictate or prescribe therapy for all diseases and medical disabilities, and, for all practical purposes, enable Congress to practise medicine."

That unvarnished view of the sanctity of the doctor-patient relationship is not likely to hold much sway with Congress as its members become increasingly conscious of the rising cost of medical care.

Vanik cited statistics showing that 66 per cent of dialysis patients in Great Britain and 42.2 per cent in Canada are dialyzed at home. Vanik also asked why it should cost $147 for home dialysis in Alabama and $112 in Mississippi, or why the average physician charge is $165 in New Jersey and $136 next door in Pennysylvania.

Vanik suggested at one point in the hearings that a larger issue is at stake in the kidney program. "If we can't control this one program, treating one disease," he said, "then we can't begin to consider national health insurance or other catastrophic coverage."