HCA Inc. JOINDERAGREEMENT AND AMENDMENT NO. 1 to CREDIT AGREEMENT

Exhibit 4.1

HCA Inc.

JOINDER AGREEMENT AND AMENDMENT NO. 1 to CREDIT

AGREEMENT

JOINDER AGREEMENT AND AMENDMENT NO. 1 to CREDIT AGREEMENT (this “Joinder”), dated as of October 30, 2014 (“Increased Amount Date” or “Amendment No. 1 Effective Date”), to the Credit Agreement, dated as of September 30, 2011, as amended and restated as of March 7, 2014, among HCA Inc., a Delaware corporation (the “Parent Borrower”), the Subsidiary Borrowers party thereto, the lenders party thereto, Bank of America, N.A., as Administrative Agent, Swingline Lender and Letter of Credit Issuer, and the other agents and bookrunners party thereto (the “Credit Agreement”). Capitalized terms used herein and not defined herein shall have the meanings assigned to such terms in the Credit Agreement.

1. The Lenders listed on Exhibit A hereto (each, an “Incremental Revolving Loan Lender” and together, the “Incremental Revolving Loan Lenders”) have been approached by the Parent Borrower, and have committed to provide an Incremental Revolving Credit Commitment of $750,000,000 in the aggregate. After giving effect to such Incremental Revolving Credit Commitments, the aggregate Revolving Credit Commitments shall be increased on the Increased Amount Date from $2,500,000,000 to $3,250,000,000 (the “Revolving Commitment Increase”).

2. The Parent Borrower hereby represents and warrants as of the Increased Amount Date to the Administrative Agent, each Lender and the Incremental Revolving Loan Lenders that all of the conditions set forth in Section 2.14 of the Credit Agreement with respect to the Revolving Commitment Increase have been satisfied and the Parent Borrower is in compliance with all of the terms of such Section. The Increased Amount Date shall be the date that all of the conditions in Section 6 of this Joinder shall have been satisfied, which date shall be October 30, 2014.

3. Pursuant to Section 2.14 of the Credit Agreement, by execution and delivery of this Joinder, each Incremental Revolving Loan Lender’s Revolving Credit Commitment shall be the amount set forth on Exhibit A hereto and each Incremental Revolving Loan Lender shall for all purposes of the Credit Documents be deemed a “Lender” under the Credit Agreement.

4. For the avoidance of doubt, the Revolving Credit Commitments of the Incremental Revolving Loan Lenders shall be on identical terms as the Revolving Credit Commitments as in effect immediately prior to giving effect to the effectiveness of the Revolving Commitment Increase.

5. Amendments to Credit Agreement

(a) The following definition shall be added to Section 1.1 of the Credit Agreement in proper alphabetical order:

“Amendment No. 1 Effective Date”: October 30, 2014.

(b) The definition of “Revolving Credit Commitment” in Section 1.1 of the Credit Agreement shall be amended by replacing “as of the Restatement Effective Date is $2,500,000,000” with “as of the Amendment No. 1 Effective Date is $3,250,000,000, as may be increased from time to time on any Increased Amount Date to the extent of such Incremental Revolving Credit Commitment.”

(c) Schedule 1 to the Credit Agreement shall be amended and restated as provided in Exhibit A to this Joinder.

6. Conditions. The obligation of the Incremental Revolving Loan Lenders to provide the Incremental Revolving Credit Commitments and the effectiveness of the Revolving Commitment Increase referred to above are subject to the following conditions precedent:

(a) Accuracy of the Parent Borrower’s representations and warranties made in Section 2 hereto.

(b) The Administrative Agent shall have received an officer’s certificate of the Parent Borrower in form and substance reasonably satisfactory to the Administrative Agent certifying that (x) no Default or Event of Default shall have occurred and be continuing and (y) all representations and warranties made by any Credit Party contained herein or in the other Credit Documents shall be true and correct in all material respects with the same effect as though such representations and warranties had been made on and as of the date of such Credit Event (except where such representations and warranties expressly relate to an earlier date, in which case such representations and warranties shall have been true and correct in all material respects as of such earlier date), on such Increased Amount Date before and after giving effect to the Revolving Commitment Increase.

(c) The Administrative Agent shall have received the executed legal opinion of Simpson Thacher & Bartlett LLP, special New York counsel to the Parent Borrower in form and substance satisfactory to the Administrative Agent. The Parent Borrower, the other Credit Parties and the Administrative Agent hereby instruct such counsel to deliver such legal opinion.

(d) For each Credit Party, the Administrative Agent shall have received a short-form (where applicable) good standing certificate in such Credit Party’s state of formation, each dated a recent date prior to the Increased Amount Date and certified by the applicable secretary of state.

(e) The reimbursement or payment of all reasonable out-of-pocket expenses (including the reasonable fees and expenses of Cahill Gordon & Reindel llp, special counsel to the Administrative Agent) required to be reimbursed or paid by the Parent Borrower hereunder or under the Credit Agreement, in each case to the extent invoiced.

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7. On the Increased Amount Date, subject to the satisfaction of the terms and conditions set forth herein, (x) (i) each of the Lenders with Revolving Credit Commitments shall assign to the Incremental Revolving Loan Lenders and the Incremental Revolving Loan Lenders shall purchase from each of the Lenders with Revolving Credit Commitments, at the principal amount thereof (together with accrued interest), such interests in the Revolving Credit Loans outstanding on the Increased Amount Date as shall be necessary in order that, after giving effect to all such assignments and purchases, such Revolving Credit Loans will be held by existing Lenders with Revolving Credit Commitments and the Incremental Revolving Loan Lenders ratably in accordance with their Revolving Credit Commitments after giving effect to the addition of the Revolving Commitment Increase to the Revolving Credit Commitments.

8. The Credit Parties hereby confirm that the Security Documents and the obligations of such parties under the Credit Documents continue in full force and effect and shall not be affected by this Joinder (it being understood that the “Obligations” are increased as provided herein). Each of Holdings and Parent Borrower hereby further ratifies and reaffirms the validity and enforceability of all of the Liens and security interests heretofore granted, pursuant to and in connection with the Security Documents, to the Administrative Agent, as collateral security for the Obligations under the Credit Documents in accordance with their respective terms, and acknowledges that all of such Liens and security interests, and all Collateral heretofore pledged as security for such Obligations, continue to be and remain Collateral for such obligations from and after the date hereof.

9. This Joinder shall be deemed a Credit Document under the Credit Agreement.

10. Severability. Any provision of this Joinder held to be invalid, illegal or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such invalidity, illegality or unenforceability without affecting the validity, legality and enforceability of the remaining provisions hereof; and the invalidity of a particular provision in a particular jurisdiction shall not invalidate such provision in any other jurisdiction.

11. GOVERNING LAW. THIS JOINDER AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES HEREUNDER SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

12. Submission to Jurisdiction; Waivers. Each party hereto irrevocably and unconditionally:

(a) submits for itself and its property in any legal action or proceeding relating to this Joinder, or for recognition and enforcement of any judgment in respect thereof, to the exclusive general jurisdiction of the courts of the State of New York, borough of Manhattan, the courts of the United States of America for the Southern District of New York and appellate courts from any thereof;

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(b) consents that any such action or proceeding may be brought in such courts and waives any objection that it may now or hereafter have to the venue of any such action or proceeding in any such court or that such action or proceeding was brought in an inconvenient court and agrees not to plead or claim the same;

(c) agrees that service of process in any such action or proceeding may be effected by mailing a copy thereof by registered or certified mail (or any substantially similar form of mail), postage prepaid, to such Person at its address set forth on Schedule 14.2 to the Credit Agreement or at such other address of which the Administrative Agent shall have been notified pursuant to Section 14.2 of the Credit Agreement;

(d) agrees that nothing herein shall affect the right to effect service of process in any other manner permitted by law or shall limit the right to sue in any other jurisdiction; and

(e) waives, to the maximum extent not prohibited by law, any right it may have to claim or recover in any legal action or proceeding referred to in this Section 12 any special, exemplary, punitive or consequential damages.

13. WAIVERS OF JURY TRIAL. PARENT BORROWER, EACH CREDIT PARTY, THE ADMINISTRATIVE AGENT AND EACH LENDER HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVE TRIAL BY JURY IN ANY LEGAL ACTION OR PROCEEDING RELATING TO THIS JOINDER AND FOR ANY COUNTERCLAIM THEREIN.

14. Counterparts. This Joinder may be executed in counterparts (and by different parties hereto on different counterparts), each of which shall constitute an original, but all of which when taken together shall constitute a single contract. Delivery by facsimile or email of an executed counterpart of a signature page to this Joinder shall be effective as delivery of an original executed counterpart of this Joinder.

[Signature Pages Follow]

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IN WITNESS WHEREOF, the parties hereto duly executed this Joinder as of the day and year first above written.

[Signature Page to Joinder Agreement and Amendment No. 1]

[ADDITIONAL LENDER SIGNATURES OMITTED]

[Signature Page to Joinder Agreement and Amendment No. 1]

SCHEDULE A

TO JOINDER AGREEMENT

Schedule A-1

Schedule A-2

Schedule A-3

Schedule A-4

Schedule A-5

Schedule A-6