For the past three years, Dolores Serna has build up a large service bill after relying on an ambulance to get her to doctor appointments.
She has several medical conditions such as diabetes, congestive heart failure and kidney and lung failure.
Dolores said her leg muscles are completely deteriorated, so she calls on an ambulance to get to the doctor TMs office.
"They take me to the doctor's (office), they take me to the Valley Eye Center and they take me to the dialysis," she said.
Her husband, Hilario Serna, has kept true to his vows of for better or worse.
It takes him about an hour and a half to bathe Dolores, change the sheets on her bed and take care of hygiene needs.
"It's been real hard for us because I TMm 80-years-old and I only have one hand to work with," Serna said.
But the couple said things have been a little more stressful since they began receiving letters from their Medicare provider, notifying them that the ambulance service Dolores frequently uses, is not covered.
According to the couple, it means they have an ambulance service bill of about $300,000 that have accumulated over the past three years.
It's owed to the South Texas Emergency Care Foundation.
"My husband and I live on about $1,300 a month, Dolores said. Just imagine if we were to send $1,000 a month| We wouldn't even take a chip off of what we owe| It's useless."
Rene Perez, at STEC, said he can't talk about specific patients, but he said that Medicare reform has gotten stricter on payment of ambulance services.
Perez said that in general, when a patient first receives a letter notifying them of the unfavorable case to pay for services, they can provide more information and ask for a second review by the Medicare provider.
However, Perez said, sometimes Medicare will still refuse and payment falls on the patient.
"If I don TMt have my transportation what's going to happen to me?" Dolores Serna said.