One of the biggest issues facing President Trump and Congressional leaders is how best to reform the nation’s healthcare system. The President was elected, in part, on his promise to repeal and replace the Affordable Care Act, also known as Obamacare. What once appeared to be a Day One action, is now looking to take months as policymakers work through some of the challenges of unraveling the ACA. And the recently released repeal/repair healthcare bill that’s being supported by the White House and Republican leadership threatens to make coverage inaccessible, jeopardizing tens of millions of American families who have coverage.

From my perspective, taking some time to make sure any changes are done correctly and in a way that improves the healthcare system is prudent.

During the most recent enrollment period, more than 6.4 million Americans signed up for health insurance through the Affordable Care Act; and the federal government expects more than 11 million to be enrolled in the ACA exchanges this year. Many of them have no other choice for insurance because their employer doesn’t offer coverage, they’re underemployed, or they need government subsidies to help them pay their premiums. That more Americans have health insurance is a positive development. It means that there are more healthy people to level out the insurance risk pool and fewer patients who are showing up to hospitals and clinics with no way to pay for their care.

However on the other hand, with the passage of the ACA, many Americans lost access to their long-time doctor or they couldn’t keep the coverage they wanted. And there still has been little success containing rising healthcare costs. In fact, in my home state of Arizona, premiums for 2017 rose by 116 percent, a higher rate than in any other state, as insurers dropped out of the exchange.

Now as Congress works to repeal the healthcare law, the President’s call for a simultaneous replacement bill will, hopefully, ensure that individuals are able to maintain their insurance coverage and patients won’t slip through the cracks.

Because of federal law, the medical community in the United States has a long-standing mandate that patients coming to emergency rooms for care will not be turned away for inability to pay. That is humane and right. However, for hospitals trying to manage costs it’s difficult to ease the financial burden created by the requirement to provide care 24/7, regardless of a patient’s ability to pay.

The Congressional Budget Office calculated that 18 million people would lose their insurance in the first year after the ACA was repealed. By 2026, that number is expected to rise to 32 million. That would mean that millions of patients would present at their local emergency rooms and doctors’ offices, unable to pay their bills. This is simply unacceptable and makes our healthcare system unsustainable unless there are fixes.

As the director of a rural public health system, I saw firsthand the challenges hospitals face providing care to underserved and uninsured populations. We struggled month after month balancing the needs of our patient population with the cost realties of providing those services. Thankfully we were able to meet patients’ needs, but it was in large part because reliable government payments – Medicare and Medicaid – helped fill the gap.

And while there are a number of forces working to protect Medicaid and Medicaid expansion efforts, very little is being said about the potential consequences to Medicare.

More than $700 billion was cut from Medicare to help pay for the healthcare law. At the time of the bill’s passage, hospitals okayed the Medicare cuts because they recognized that an increase in insured patients would ultimately make up the financial difference. However, that financial balance would be destroyed if Congress repealed the ACA without reversing those cuts, leaving huge holes in our healthcare system’s safety net.

According to a study by the healthcare consultancy, Dobson/DaVanzo, hospitals would find their revenue reduced by $455.3 billion by 2026 under a straight repeal of the Affordable Care Act that does not restore Medicare funding. This shortfall would be disastrous for hospitals – possibly forcing many of them to cut back on service hours or specialized care, or even close for good.

The U.S. healthcare system is tightly woven together. If you carelessly pull one thread, others move, gaps appear, and the whole fabric can tear. That’s why it has always been so important to move with caution when passing laws designed to reform the system. No matter how well-intentioned those reforms might be, unforeseen consequences are just one small mistake away.

Not restoring Medicare funding is the equivalent of pulling the string that unravels the whole cloth. The serious damage it would inflict upon U.S. hospitals would be felt throughout the healthcare system and into the wider economy.