(a) The board may issue revenue bonds to:
(1) acquire, purchase, construct, repair, renovate, or equip buildings or improvements for hospital system purposes;
(2) acquire sites to be used for hospital system purposes; or
(3) acquire and operate a mobile emergency medical service to assist the district in carrying out its hospital purposes.
(b) The bonds must be payable from and secured by a pledge of all or part of the revenues derived from the operation of the district's hospital system.
(c) The bonds may be additionally secured by a mortgage or deed of trust lien on all or part of district property.
(d) The bonds must be issued in the manner provided by Sections 264.042, 264.043, and 264.046-264.049, Health and Safety Code, for issuance of revenue bonds by a county hospital authority.