Hope this link may help:
Emergency Care at Non-VA Facilities Frequently Asked Questions (FAQs) (Health Care Eligibility)
Do I need to get approval before going to the emergency room?
No. If you are an eligible veteran, a VA facility is not feasibly available, and you believe your health or life is in immediate danger, report directly to the closest emergency room. You, your representative, or the treating facility should then contact the nearest VA as soon as possible (within 48 hours) to arrange a transfer to VA care, if hospitalization is required.
How long will I stay in the private hospital?
If you are hospitalized, VA will be in regular contact with your physician at the private hospital. As soon as your condition stabilizes, VA will arrange to transport you to a VA, or VA-designated facility.
What if the hospital bills me for services?
If you are billed for emergency care services, contact your local VA health care facility and representative will assist you in resolving the issue.