Last January, Malcolm Bird took his 1-year-old daughter, Colette, to the local emergency room. His wife had accidentally cut the young girl's pinky finger while clipping her fingernails, and it had begun to bleed. They were nervous, first-time parents who wanted a doctor's opinion.

Colette turned out to be completely fine. A doctor ran her finger under the tap, stuck a Band-Aid on her pinky, and sent the family home.

A week later, something else showed up at home: a $629 hospital bill for the Band-Aid and its placement on Colette's finger.

His insurance had negotiated the price down to $440.30, the amount Bird — who was still in his deductible — was expected to pay.

"My first thought was, how could this possibly cost $629?" Bird told me when we spoke in April. "So I wrote the hospital a letter, expecting them to say, yeah, that's a bit excessive, and lower the price."

That didn't happen. The hospital sent him back a long letter explaining why it would stick with the price. The fees, the hospital's leadership responded, were justified — and it ultimately sent his unpaid bill to a debt collection agency.

Bird sent me all his correspondence with the hospital, which I ran by medical billing experts. His experience provides a unique window into how emergency health care billing works in the United States, and how easy it is for customers to end with a surprise bill for a relatively small service — like a Band-Aid on a child's finger.

"5 minutes, water, gauze, and a band aid, is that really $629?"

Here's what happened when Colette went to the emergency department, as recounted by her father, Malcolm.

They showed up and waited about 20 minutes until they were called back and placed into an exam room. A nurse came by and checked on them, and a few minutes later a doctor came in.

"He tells us that Colette is okay, that the reason it's bleeding so much is because there are so many capillaries at the end of the finger," Bird said. "Then he literally runs the finger under the tap, dries it, puts a Band-Aid on it, and says that's it. We're very relieved, we go back to the car, and the Band-Aid falls off. But it was fine because it had stopped bleeding."

Everything about the visit, he says, seemed fine — the doctor, the nurse, all of them were reassuring and provided appropriate care.

Then the $629 charge arrived. To Bird, this seems nuts — in his view, the hospital wanted him to pay $629 for a Band-Aid. Even though his insurance had negotiated the price down to $440, he was still incensed by that initial number.

"I'm not saying you shouldn't make a profit … but 5 minutes, water, gauze, and a band aid, is that really $629?" he wrote in a July letter to the hospital.

About two weeks later, the hospital's chief executive responded — yes, it was.

This was John Murphy, who is the chief executive of the Western Connecticut Health Network, which owns the hospital where Colette was seen. He wrote back to share "a different perspective" on the emergency bill.

First, he points out that the Band-Aid didn't cost $629; it was actually just $7. The other $622 was the cost of seeing the doctor and using the emergency department itself.

All emergency departments have a "facility fee" — essentially a cover charge for anyone who seeks care

Here, Murphy touches on an important concept in emergency department billing — the part that explains how bills for ER visits can be so high.

"The remainder of the charge," he writes, "was associated with the use of the facility and staff. We staff the emergency department 24-hours a day, every day of the year, and stand ready to treat whoever walks through our door, be it a gunshot victim or a patient with a stroke."

Murphy is explaining something called a "facility fee," the base price of setting foot inside an emergency room. It's something akin to the cover charge you'd pay for going out to a nightclub.

"It's the fixed price, and that's just what you're going to have to pay," says Renee Hsia, a professor at University of California San Francisco who studies emergency billing.

In the hospital view, an emergency room patient like Colette — even though she had a quite minor injury — shares the burden for that service that the Connecticut Hospital provided.

Is the hospital right? Is a $629 charge to place an emergency Band-Aid a fair cost?

Hsia has studied thousands of emergency room bills. With Bird's permission, I shared his letters and bills with her, and we talked about them a few days later.

"I see both sides," she says. "I think there are going to be facility charges regardless of the actual service that will always be part of ER care. But where this father has a reasonable point is that when you look at the cost of the Band-Aid and the proportional overhead, it just feels really crazy."

Hsia says the thing that infuriates her is how common bills like this are; she sees them all the time. The amount is almost impossible to predict, because facility fees vary widely and hospitals rarely make the numbers public. One of her studies on ER bills for common procedures showed that prices can vary from as little to $15 to as much as $17,797. And a lot of that depends on the given hospital's facility fees.

"Facility fees are very arbitrary. There doesn't seem to be any rhyme or reason to it."

"Facility fees are very arbitrary," she says. "There doesn't seem to be any rhyme or reason to it, which can be really frustrating. There are some places where the basic facility fee can be over $1,000."

I asked the communications department at Western Connecticut Health Network to explain to me how facility fees are set at Danbury Hospital, where Colette was seen. Do they count up the number of new purchases they'd need plus the cost of physician salaries, and come up with a number? Did they look at historical trends about how many patients they might see?

Western Connecticut Health Network never answered my question. Instead, four days after my inquiry, they reversed Bird's bill entirely. I received a statement from their chief financial officer, Steven Rosenberg, that said, "We are pleased to share this matter has been resolved to the satisfaction of both parties."

I followed up, asking, for a second time, how the bill was set in the first place. I never received a response.

How facility fees vex the American health care system

A lot of times, health insurance plans insulate us from facility fees. If a plan has, for example, a $50 copayment for an ER visit, then the patient never really interacts with the facility fee. She pays the copayment and is on her way.

But that's increasingly not the way American health care works. Deductibles have risen steadily over the past decade, meaning that patients are more likely to bear the full brunt of their health care bills. That's what happened to Bird; it was early January, and he was still within his annual deductible during that hospital visit.

One possible solution to draw from Colette's case would be to scale facility fees to the severity of injury — charge a lower fee, for example, for something like a cut finger and a higher fee to a stroke victim who needs more resources.

But this billing system has its own flaws. Medicare has historically relied on tiered facility fees, with five different prices tethered to the complexity of the case. But it's recently found that providers seemed to be "upcharging" their facility fees — picking codes that paid higher rates than the severity of their case should permit.

A simpler solution might be transparency — requiring hospitals to post their facility fees on the door so that patients have a sense of what the base price is for entry. Bird says that would have helped in his situation; if he'd seen the typical charges, he probably would have just called a friend who was a doctor.

"Maybe that's what we should have done, but when you're a new parent, you feel like you just want to go to the hospital and make sure everything is all right," he says. "You shouldn't be frightened to buy a Band-Aid."

And right now there aren't any federal laws that require that type of transparency. Some hospitals here and there make their prices public (one in Michigan even posts its emergency department prices online). But if you don't happen to go to one of those, you can often find yourself out of luck — like Bird did.

Bird ended up all right; the hospital reversed his bill after my inquiry (and after, a few days earlier, Bird had requested contact information for their general counsel). But there are lots of patients who don't end up okay. Two-thirds of bankruptcies in the United States have to do with medical bills — and many of those patients likely had little ability, in advance, to know just how big those bills would be.

Have you faced a medical bill like this? Tell us about it. E-mail your story to Sarah Kliff here.

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