NEW YORK (Reuters) - As the U.S. Supreme Court takes on a make-or-break Obamacare case this week, a growing number of U.S. patients and their doctors are already devising a Plan B in case they lose medical coverage.

The Court's ruling, expected by late June, will determine whether millions of Americans will keep receiving federal subsidies to help them pay for private health insurance under President Barack Obama's healthcare law.

The White House, which said it is confident the justices will rule in favor of the subsidies that are a key element of Obamacare, said it has no immediate fix if the decision goes the other way.

But even physicians who think the court will uphold the subsidies are gearing up for the worst.

Worried about newly-insured patients such as those who have just begun treatment for cancer or other serious illnesses, they are dusting off playbooks they retired when Obamacare slashed the number of uninsured people.

Interviews with doctors reached through professional groups show that they are lining up free clinics to care for patients with chronic illnesses, asking pharmaceutical companies to provide discounted drugs, and moving up preventive-care appointments and complicated procedures.

"We have to be able to navigate this on behalf of our patients if it comes about," said Dr. Jeff Huebner, a family physician in Madison, Wisconsin, one of the affected states.

In King v. Burwell, the Court will decide whether the Affordable Care Act permits government subsidies for citizens of at least 34 states which use the federal marketplace to buy health insurance. It will hear oral arguments on Wednesday.

If the justices rule that only residents of states running their own exchanges are eligible for subsidies, some 9.3 million people will have to pay their full monthly premium or lose coverage, estimates the nonpartisan Urban Institute. About 6 million are expected to be unable to afford it.

Many providers as well as patients are unaware of the looming threat, but some physicians are already preparing for it.

Last weekend, leaders of the National Physicians Alliance, which supports the Affordable Care Act and works to improve access to medical care, met in Washington to discuss how to work with community organizations to arrange healthcare for people who might become uninsured, said Huebner, who chairs the group's policy committee.

"The ideas include finding organizations that make referrals to free clinics, encouraging patients to check if they qualify for Medicaid or other state programs, and if they can't get insurance then find a regular source of care that accepts payment on a sliding scale" based on ability to pay, Huebner said.

He and other physicians are also scheduling Obamacare patients for preventive screenings, completing lab work, and writing prescription refills.

"I would advise patients in this boat to schedule a visit with their primary care provider as soon as they can" to set up "transition plans," Huebner said.


If the court rules against the administration, premium subsidies for people in the affected states could end immediately, though insurers would be obliged to give 90 days notice before ending coverage, according to Aetna Inc. chief executive Mark Bertolini. None of the affected states have announced contingency plans, but some are considering alternatives to help residents maintain coverage.

In Brewton, Alabama, pediatrician Marsha Raulerson has persuaded one drug company to provide an expensive asthma medication to one of her patients if she loses her insurance.

"But after a few months you have to re-apply" and show that the patient is still unable to afford medication, Raulerson said. "It's not an easy process, especially if you have to do it for a lot of patients."

She is also stockpiling as many free samples as she can. Dr. Robert Wergin, a primary care physician in Milford, Nebraska, is scrambling to locate labs and imaging centers that offer the lowest prices for blood tests, X-rays and MRIs.

"Around here, people feel responsible for their bills and I'm not sure they would come in if they lost insurance and couldn't pay," Wergin said.

Some patients, reached through social service organizations that helped them sign up for Obamacare, are aware of the potential loss of subsidies and are trying to schedule medical procedures before the Court rules.

Yolanda Diaz, 27, is one of them. A single mother of two, she suffers from occasional blackouts that last several minutes. She cannot afford the full premium on her wages as a pantry manager at Brevard County, Florida, community center so she pays $74.95 a month and the rest is covered by a $205 Obamacare subsidy.

Her coverage began this month, Diaz said, and the first thing she did was make appointments for an MRI and CT scans in hopes of identifying the cause of the blackouts.

"I would hate to have to go to the ER, but if the subsidies get taken away I don't know what I'll do," she said. U.S. law requires hospitals to treat all emergency cases regardless of ability to pay, so many uninsured patients seek care there.

Of those expected to be priced out of insurance in case of unfavorable ruling, the Urban Institute estimated 81 percent are, like Diaz, employed full- or part-time.

So is Theresa Cabot-Walmer. The 58-year-old Pennsylvanian pays $79 a month and receives a subsidy of about $400. On her 5-hours-a-day job as a shipping clerk she could never afford the full premium, she said.

Her coverage has allowed her to see a physical therapist for a serious knee injury and avoid a knee-replacement surgery. If the Court eliminates subsidies, she plans to ask if the therapist will accept lower payments. But because that is not a sure thing, Cabot-Walmer is considering her plan B.

"I might try to schedule knee-replacement surgery while I still have insurance."

(Reporting by Sharon Begley and Caroline Humer; Editing by Michele Gershberg and Tomasz Janowski)