EXHIBIT 3.283

Delaware

The First State

I, HARRIET SMITH WINDSOR, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO HEREBY CERTIFY THE ATTACHED ARE TRUE AND CORRECT COPIES OF ALL DOCUMENTS ON FILE OF “NAVARRO REGIONAL, LLC” AS RECEIVED AND FILED IN THIS OFFICE.

THE FOLLOWING DOCUMENTS HAVE BEEN CERTIFIED:

CERTIFICATE OF FORMATION, FILED THE NINTH DAY OF NOVEMBER, A.D. 1998, AT 9 O’CLOCK A.M.

AND I DO HEREBY FURTHER CERTIFY THAT THE AFORESAID CERTIFICATES ARE THE ONLY CERTIFICATES ON RECORD OF THE AFORESAID LIMITED LIABILITY COMPANY, “NAVARRO REGIONAL, LLC”.

2964393     8100H     070789160

/s/ Harriet Smith Windsor

Harriet Smith Windsor, Secretary of State

AUTHENTICATION: 5821749

DATE: 07-06-07

CERTIFICATE OF FORMATION

OF

NAVARRO REGIONAL, LLC

Under Section 18-201 of the

Delaware Limited Liability Company Act

FIRST: The name of the limited liability company is Navarro Regional, LLC (the “Company”).

SECOND: The address of the registered office of the Company in the State of Delaware is 1013 Centre Road, Wilmington, Delaware 19805.

THIRD: The name and address of the Company’s registered agent for service of process is Corporation Service Company, 1013 Centre Road, Wilmington, Delaware 19805.

IN WITNESS WHEREOF, the undersigned has executed this Certificate of Formation as of October, 30, 1998.

By: /s/ John M. Franck II

Name: John M. Franck II

Title: Authorized Person

STATE OF DELAWARE

SECRETARY OF STATE

DIVISION OF CORPORATIONS

FILED 09:00 AM 11/09/1998

981430399-2964393

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