DAVENPORT, Iowa — When former Coast Guardsman Amanda Wolfe went to the emergency room because her appendix was about to burst in September 2016, she figured her insurance would cover the cost. She had two kinds of insurance — a private plan she paid for and her Veterans Affairs benefits.

The emergency appendectomy went well and Wolfe made a speedy recovery. Her private insurance covered most of the more than $20,000 bill for her hospital stay. But six months later, the VA denied her claim for the roughly $2,500 that remained, putting her in an unexpected financial bind. She has been appealing ever since.

"It's one of those things where you thought that they would be there and they're not," said Wolfe, who adopted her nephew soon after the surgery and has been watching her budget to care for him.

Wolfe thought she was living in her own private insurance hell, until a report from the VA's internal watchdog revealed problems in the way the VA reimburses veterans for emergency care at non-VA facilities.

In one recent six-month period, according to a report from the VA's Office of Inspector General released last week, the VA left about 17,400 veterans to pay out-of-pocket for emergency medical treatment the government should have covered. The report said that between April 1 and Sept. 30, 2017, veterans who got emergency care at non-VA facilities were forced to pay $53.3 million in medical bills they never should have had to pay.

The IG report came after a 2017 investigation by Minneapolis/St. Paul station KARE, in which whistleblowers told the NBC News affiliate that it was faster to deny claims than to approve them.

Members of Congress, including the chairs of the House and Senate Veterans Affairs Committees sent a letter to the VA on Monday, demanding answers.

"No veteran should be afraid to seek care in an emergency room," said Rep. Chris Pappas, D-N.H., who signed the letter. "Clearly the bureaucracy is favoring speed over accuracy, it's favoring efficiency over the health of our veterans. We've got to make sure that we're putting veterans first."

The Inspector General found that the office that processes emergency claims like Wolfe's had been prioritizing speed over accuracy, even offering incentives like overtime pay for processing claims quickly and without concern for accuracy. According to the report, about 31 percent of denied or rejected emergency care claims had been inappropriately processed.

Read the full report here.

Inspectors also found that there was a massive backlog in sending bills to patients, even time-sensitive ones that narrowed the window in which they could appeal a denial. During three different facility visits, inspectors found "stacks of unsent claims decision letters printed between one and two months prior."

In interviews and surveys, employees told inspectors they were "verbally directed or encouraged to deny non-VA emergency claims to meet production standards."

'I couldn't stand up straight'

Wolfe said she did not go to a VA hospital for her appendix because the nearest one was a two-and-a-half hour drive away.

"By 10:00 a.m., I couldn't stand up straight," she said. "I certainly could've attempted the drive. I don't know that I would've made the drive."

Bart Stichman, executive director of the National Veterans Legal Services Program, said that emergency medical expenses form a significant portion of the care sought by veterans — and the VA ought to pay those expenses.

"An emergency is a devastating situation for veterans in the first place," said Stichman, whose group provides free legal aid to veterans. "But the financial toll, when the VA erroneously denies your claim for reimbursement, can be just as devastating."

Since the end of September 2017, the last month of the period covered by the inspector general's report, there have been many leadership changes within the VA, including three different directors of the office that processes emergency claims. The inspectors say the instability apparently allowed problems to continue.

In a statement, the VA told NBC News it is reviewing the claims in the Inspector General report for possible payment to veterans.

"It's alarming. It's worrisome," said Wolfe, who read the report. She paid off her bill in 2017, but is still fighting for reimbursement. "They need to get the process back on track...not just for myself, but for all the other veterans who are impacted."