This chapter applies only to a county that is not served by a hospital district and:
(1) is located in the Texas-Louisiana border region, as that region is defined by Section 2056.002, Government Code, and has a population of more than 90,000 but less than 200,000; or
(2) has a population of less than 51,000 and is adjacent to a county with a population of more than 200,000 but less than 233,500.