AMENDMENT NO. 6 TO CREDIT AGREEMENT Dated as of March 12, 2004

Exhibit 10.1

AMENDMENT NO. 6 TO CREDIT AGREEMENT

Dated as of March 12, 2004

among

TRIAD HOSPITALS, INC.,

as Borrower

AND

BANK OF AMERICA, N.A.,

as Administrative Agent on behalf of itself and the Lenders

Arranged By:

BANC OF AMERICA SECURITIES LLC and THE BANK OF NOVA SCOTIA

as Joint Lead Arrangers

AND

BANC OF AMERICA SECURITIES LLC, THE BANK OF NOVA SCOTIA AND FLEET NATIONAL

BANK

as Joint Book Runners

AMENDMENT NO. 6

THIS AMENDMENT NO. 6 dated as of March 12, 2004 (this “Amendment”) to the Credit Agreement referenced below is by and among Triad Hospitals, Inc., a Delaware corporation (the “Borrower”), and Bank of America, N.A., as Administrative Agent on behalf of itself and the Lenders.

W I T N E S S E T H

WHEREAS, a $1.2 billion credit facility was established in favor of the Borrower pursuant to the terms of that Amended and Restated Credit Agreement dated as of April 27, 2001 (as amended and modified from time to time, the “Credit Agreement”) among the Borrower, the lenders identified therein and Bank of America, N.A., as Administrative Agent;

WHEREAS, the Borrower has requested certain modifications to the Credit Agreement; and

WHEREAS, the requisite Lenders have agreed to the requested modifications and the above-referenced waiver on the terms and conditions set forth herein and have directed the Administrative Agent to enter into this Amendment for and on their behalf.

NOW, THEREFORE, IN CONSIDERATION of the premises and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. Defined Terms. Capitalized terms used herein but not otherwise defined herein shall have the meanings provided to such terms in the Credit Agreement.

2. Amendments. The Credit Agreement is amended in the following respects:

2.1 The following paragraph and grid are hereby added after the first paragraph in the definition of “Applicable Percentage” in Section 1.1 to read as follows:

Notwithstanding the foregoing, on and after the Amendment No. 6 Effective Date, the Applicable Percentage for the Term Loan B Facility shall be subject to the rates per annum set forth below opposite the applicable Consolidated Total Leverage Ratio then in effect, it being understood that (i) the Applicable Percentage for Base Rate Loans shall be the percentage set forth under the column “Term Loan B Base Rate Loans” and (ii) the Applicable Percentage for Eurodollar Loans shall be the percentage set forth under the column “Term Loan B Eurodollar Loans”. Therefore, on the Amendment No. 6 Effective Date, the Applicable Percentage with respect to Eurodollar Loans under the Term Loan B Facility shall be reduced from 3.00% to 2.25% per annum and the Applicable Percentage with respect to Base Rate Loans under the Term Loan B Facility shall be reduced from 2.00% per annum to 1.25% per annum.

2.2 Subclause (ii) in the definition of “Approved Asset Disposition” in Section 1.1 is hereby amended to read as follows:

(ii) up to the first twelve (12) facilities sold or disposed of by any member of the Consolidated Group after the Closing Date;

2.3 A new subsection (K) is hereby added after subsection (J) in the definition of “Asset Disposition” in Section 1.1 and shall read as follows:

and (K) the lease by the Borrower of (I) that certain Cessna Citation Encore, manufacturer’s Serial Number ###-###-####, Registration Number N511TH and (II) that certain Cessna Citation X, manufacturer’s Serial Number ###-###-####, Registration Number N40KW (collectively, the “Jets”).

2.4 A new subclause (f) is added at the end of the first sentence in the definition of “Change of Control” set forth in Section 1.1 and shall read as follows:

or (f) the occurrence of a “Change in Control” under and as defined in the 2004 Refinancing Debt.

2.5 Subclause (iii) in the definition of “Excluded Property” in Section 1.1 is hereby amended to read as follows:

(iii)(a) which consists of real property that existed or was acquired prior to the Amendment No. 6 Effective Date and has a fair market value of less than $15 million or (b) which consists of real property that did not exist until after, or was acquired after, the Amendment No. 6 Effective Date or

2.6 A new subclause (iv) in the definition of “Excluded Property” in Section 1.1 is hereby added to read as follows:

(iv) those properties which consist of real property acquired from Tenet Healthcare Corporation or any subsidiary thereof in December 2003.

2.7 The reference to “$5 million” in subclause (iv) and the reference to “$50 million” in subclause (vii)(B) in the definition of “Permitted Acquisition” in Section 1.1 are hereby amended to read as “$25 million” and “$100 million”, respectively.

2.8 The reference to “twenty percent (20%)” in subclause (xvi) in the definition of “Permitted Investments” in Section 1.1 is hereby amended to read as “thirty percent (30%)”.

2.9 The references to “$5 million” in subclauses (ii) and (iii) of the definition of “Pro Forma Compliance Certificate” in Section 1.1 are each hereby amended to read as “$25 million”.

2.10 The following definitions are hereby added to Section 1.1 in the appropriate alphabetical order and shall read as follows:

“2004 Refinancing Debt” has the meaning given such term in Section 9.1(o).

“Amendment No. 6 Effective Date” means March 12, 2004.

“Jets” has the meaning given such term in subclause (K) of the definition of Asset Disposition in Section 1.1.

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2.11 The last sentence of Section 3.3(b)(ii)(A) is hereby deleted in its entirety.

2.12 The reference to “$50 million” in subclause 3.3(b)(ii)(B) is hereby amended to read as “$100 million”.

2.13 The last two sentences of Section 3.3(b)(ii)(B) are hereby deleted in their entirety.

2.14 The reference to “twenty percent (20%)” in subclause (iii) of the proviso in the last sentence of Section 8.12 is hereby amended to read as “thirty percent (30%)”.

2.15 Subclause (i) in the first sentence of Section 8.13 is amended to read as follows:

(i) all of its owned personal property located in the United States, other than the Jets,

2.16 The following subclause (o) is added at the end of Section 9.1 and shall read as follows:

(o) Indebtedness of the Borrower in an aggregate principal amount up to $850 million in the form of (A) Subordinated Debt that has terms that are not materially less favorable to the Borrower than that of the Refinancing Subordinated Debt and has a weighted average maturity that is greater than that of the Loans hereunder and/or (B) unsecured senior notes that have terms that are not materially less favorable to the Borrower than that of the Senior Notes and have a weighted average maturity that is greater than that of the Loans hereunder (the “2004 Refinancing Debt”); provided that the first $600 million of the proceeds of the 2004 Refinancing Debt are used to (i) refinance the Senior Notes and pay any accrued interest, transaction costs and tender or call premiums related thereto in accordance with the terms hereof and/or (ii) voluntarily prepay the Term Loans in accordance with the terms hereof.

2.17 Subclause (C) in Section 9.5(iv) is hereby amended to read as follows:

(C) the aggregate net book value of all assets sold, leased or otherwise disposed of shall not exceed $100.0 million in any fiscal year,

2.18 The reference to “$5 million” in subclause (E) in Section 9.5(iv) is hereby amended to read as “$25 million”.

2.19 The following sentence is hereby added at the end of clause (iv) of Section 9.5 and shall read as follows:

Notwithstanding subclause (A) above, a member of the Consolidated Group may make an Asset Disposition which otherwise complies with the rest of the requirements contained in this Section 9.5(iv) for consideration consisting of loans, advances or extensions of credit to the buyer provided that such consideration consisting of loans, advances or extensions of credit does not exceed $50 million in the aggregate at any one time outstanding.

2.20 The following sentence is hereby added as a separate paragraph at the end of Section 9.5 and shall read as follows:

In addition to the foregoing, any member of the Consolidated Group may make Asset Dispositions by way of donation, transfer or other disposition of assets (whether real or personal property including cash) to State or local municipalities (or other Governmental Authorities),

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nonprofit organizations, foundations, charities or similar entities of its choice in an aggregate principal amount (for the Consolidated Group) of up to $10 million in any fiscal year.

2.21 The following proviso is hereby added at the end of subsection (d) of Section 9.8 and shall read as follows:

provided, further, however, that the Borrower may refinance the Senior Notes with the 2004 Refinancing Debt.

2.22 Clause (ii) of Section 9.11 is hereby amended to read as follows:

(ii) pursuant to the terms of the Senior Subordinated Notes, the Refinancing Subordinated Debt or the 2004 Refinancing Debt,

2.23 The reference to “twenty percent (20%)” in the second proviso in Section 9.12 is hereby amended to read as “thirty percent (30%)”.

2.24 Clause (i) in Section 10.1(g) is hereby amended to read as follows:

(i) The occurrence of an Event of Default under and as defined under the Senior Notes, Interim Loan, Senior Subordinated Notes, the Refinancing Subordinated Debt, the 2004 Refinancing Debt or the indentures or other governing instruments relating thereto (in each case, if such Indebtedness is then outstanding);

3. The Guarantors join in the execution of this Amendment for purposes of acknowledging and consenting to the terms of this Amendment and reaffirming their guaranty obligations under the Guaranty Agreement.

4. The Borrower affirms that the representations and warranties in the Credit Agreement and the other Credit Documents are true and correct in all material respects as of the date hereof (except those which expressly relate to an earlier period or date and except to the extent that changes in facts and conditions on which such representations and warranties are based are required or permitted under the Credit Agreement).

5. (i) This Amendment, other than Section 2.1, shall be effective as of the date hereof upon receipt by the Administrative Agent of executed signature pages to this Amendment from each of the parties hereto and executed copies of consents from the Required Lenders and (ii) Section 2.1 shall be effective as of the date hereof upon receipt by the Administrative Agent of executed signature pages to this Amendment from each of the parties hereto and executed copies of consents from the Required Lenders and all of the Tranche B Term Lenders. The effectiveness of this Amendment is also subject to receipt by the Administrative Agent of the amendment fee equal to five basis points (0.05%) on (A) the Revolving Commitments of the Revolving Lenders consenting to this Amendment and (B) the outstanding Term Loans of the Term Lenders consenting to this Amendment.

6. Except as modified hereby, all of the terms and provisions of the Credit Agreement (including Schedules and Exhibits) shall remain in full force and effect.

7. The Borrower agrees to pay all reasonable costs and expenses of the Administrative Agent in connection with the preparation, execution and delivery of this Amendment, including without limitation the reasonable fees and expenses of Moore & Van Allen, PLLC.

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8. This Amendment may be executed in any number of counterparts, each of which when so executed and delivered shall be deemed an original, and it shall not be necessary in making proof of this Amendment to produce or account for more than one such counterpart.

9. This Amendment shall be deemed to be a contract made under, and for all purposes shall be construed in accordance with, the laws of the State of New York.

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IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart of this Amendment to be duly executed and delivered as of the date and year first above written.

Consented to by:

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