THIRD SUPPLEMENTAL INDENTURE

                     TENET HEALTHCARE CORPORATION, as Issuer

                                      AND

                              THE BANK OF NEW YORK,

                                   as Trustee

                             Dated as of May 7, 1998

                     Supplemental to Indenture, dated as of

                     March 1, 1995, relating to the Issuer's

                   10 1/8% Senior Subordinated Notes Due 2005


                                       


                                TABLE OF CONTENTS



                                                                             
PARTIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RECITALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ARTICLE I            DEFINITIONS AND OTHER PROVISIONS
                     OF GENERAL APPLICATION. . . . . . . . . . . . . . . . . .

     SECTION 1.1     Definitions . . . . . . . . . . . . . . . . . . . . . . .

     SECTION 1.2     Effect of Headings and Table of
                      Contents . . . . . . . . . . . . . . . . . . . . . . . .

     SECTION 1.3     Successors and Assigns. . . . . . . . . . . . . . . . . .

     SECTION 1.4     Separability Clause . . . . . . . . . . . . . . . . . . .

     SECTION 1.5     Benefits of Third Supplemental
                     Indenture . . . . . . . . . . . . . . . . . . . . . . . .

     SECTION 1.6     Governing Law . . . . . . . . . . . . . . . . . . . . . .

     SECTION 1.7     Effectiveness . . . . . . . . . . . . . . . . . . . . . .

ARTICLE II           THE AMENDMENTS. . . . . . . . . . . . . . . . . . . . . .

     SECTION 2.1     Amendments to Section 1.01. . . . . . . . . . . . . . . .

     SECTION 2.2     Amendment to Section 1.02 . . . . . . . . . . . . . . . .

     SECTION 2.3     Amendment to Section 4.04 . . . . . . . . . . . . . . . .

     SECTION 2.4     Amendment to Section 4.05 . . . . . . . . . . . . . . . .

     SECTION 2.5     Amendment to Section 4.07 . . . . . . . . . . . . . . . .

     SECTION 2.6     Amendment to Section 4.08 . . . . . . . . . . . . . . . .


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     SECTION 2.7     Amendment to Section 4.09. . . . . . . . . . . . . . . . .

     SECTION 2.8     Amendment to Section 4.11. . . . . . . . . . . . . . . . .

     SECTION 2.9     Amendment to Section 4.12. . . . . . . . . . . . . . . . .

     SECTION 2.10    Amendment to Section 4.13. . . . . . . . . . . . . . . . .

     SECTION 2.11    Amendment to Section 4.14. . . . . . . . . . . . . . . . .

     SECTION 2.12    Amendment to Section 4.15. . . . . . . . . . . . . . . . .

     SECTION 2.13    Amendment to Section 4.16. . . . . . . . . . . . . . . . .

     SECTION 2.14    Amendment to Section 4.17. . . . . . . . . . . . . . . . .

     SECTION 2.15    Amendment to Section 5.01. . . . . . . . . . . . . . . . .

ARTICLE III          NOTICE, ENDORSEMENT AND CHANGE 
                      OF SECURITIES . . . . . . . . . . . . . . . . . . . . . .

     SECTION 3.1     Notice to Securityholders. . . . . . . . . . . . . . . . .

     SECTION 3.2     Notation on Securities . . . . . . . . . . . . . . . . . .

SIGNATURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


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                  THIRD SUPPLEMENTAL INDENTURE, dated as of May 7, 1998 (the 
"THIRD SUPPLEMENTAL INDENTURE"), between TENET HEALTHCARE CORPORATION, a 
Nevada corporation (hereinafter called the "COMPANY"), and THE BANK OF NEW 
YORK, as trustee (hereinafter called the "TRUSTEE"), under the Indenture (the 
"INDENTURE"), dated as of March 1, 1995, between the Company and the Trustee 
relating to the Company's 10 1/8% Senior Subordinated Notes Due 2005 (the 
"SECURITIES").
                                       
                             RECITALS OF THE COMPANY

                  WHEREAS, the Company proposes to amend (the "AMENDMENTS") 
the Indenture to delete substantially all of the restrictive covenants 
contained therein.

                  WHEREAS, the Company has commenced an offer to purchase any 
and all of the Securities pursuant to its Offer to Purchase and Solicitation 
of Consents dated April 23, 1998 (the "TENDER OFFER").

                  WHEREAS, the Company has solicited consents to the 
Amendments from the holders of record of the Securities.

                  WHEREAS, in accordance with Section 9.02 of the Indenture, 
the Holders of a majority of the principal amount of the Securities then 
outstanding (other than any Securities owned by the Company or any Affiliate 
of the Company) have con sented to such Amendments.

                  WHEREAS, the Board of Directors of the Company has duly 
authorized the execution and delivery of this Third Supplemental Indenture, 
the Company has delivered an Officers' Certificate and an Opinion of Counsel 
to the Trustee pursuant to Section 9.06 of the Indenture and the Company has 
done all other things necessary to make this Third Supplemental Indenture a 
valid agreement of the Company in accordance with the terms hereof and of the 
Indenture.

                  NOW THEREFORE, the Company and Trustee agree as follows for 
the benefit of the other party and for the equal and ratable benefit of the 
Holders of the Securities:



                                       
                                   ARTICLE I

                         DEFINITIONS AND OTHER PROVISIONS
                            OF GENERAL APPLICATION

     SECTION I.1   DEFINITIONS.

     For all purposes of the Indenture and this Third Supplemental Indenture, 
except as otherwise expressly provided or unless the context otherwise 
requires:

                           (1) the words "herein," "hereof" and "hereunder" and
         other words of similar import refer to the Indenture and this Third
         Supplemental Indenture as a whole and not to any particular Article, 
         Section or subdivision; and

                           (2) certain capitalized terms used but not defined
         herein shall have the meanings assigned to them in the Indenture.

     SECTION I.2   EFFECT OF HEADINGS AND TABLE OF CONTENTS.

     The Article and Section headings and the Table of Contents of this Third 
Supplemental Indenture are for convenience only and shall not affect the 
construction hereof. Except as otherwise specifically set forth herein, all 
references to Sections in the Indenture shall remain unchanged.

     SECTION I.3   SUCCESSORS AND ASSIGNS.

     All covenants and agreements in this Third Supplemental Indenture by the 
Company shall bind its successors and assigns, or any other obligor on the 
Securities, whether expressed or not.

     SECTION I.4   SEPARABILITY CLAUSE.

     In case any provision in this Third Supplemental Indenture shall be 
invalid, illegal or unenforceable, the validity, legality and enforceability 
of the remaining provisions shall not in any way be affected or impaired 
thereby.

     SECTION I.5   BENEFITS OF THIRD SUPPLEMENTAL INDENTURE.

     Nothing in this Third Supplemental Indenture, express or implied, shall 
give to any Person, other than the parties hereto and their successors 
hereunder, any 

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Paying Agent and the Holders, any benefit or any legal or equitable right, 
remedy or claim under this Third Supplemental Indenture.

     SECTION I.6   GOVERNING LAW.

     This Third Supplemental Indenture shall be governed by and construed in 
accordance with the laws of the State of New York and all rights and remedies 
shall be governed by such law without reference to its conflict of laws 
provision.

     SECTION I.7   EFFECTIVENESS.

     This Third Supplemental Indenture shall be effective on the date hereof; 
PROVIDED, that the Amendments in Article II of this Third Supplemental 
Indenture shall take effect on the date (the "EFFECTIVE DATE") that the 
Trustee shall have received an Officers' Certificate from the Company, dated 
the Effective Date, in accordance with Section 8.06 of the Indenture, stating 
that the Tender Offer has been consummated and that the Amendments in Article 
II of this Third Supplemental Indenture shall take effect on such date.
                                       
                                   ARTICLE II

                                 THE AMENDMENTS

     SECTION II.1   AMENDMENTS TO SECTION 1.01.

     The following definitions are hereby deleted from Section 1.01 of the 
Indenture: Acquired Debt, Asset Sale, Capital Lease, Capital Lease 
Obligation, Capital Stock, Change of Control, Change of Control Triggering 
Event, Consolidated Cash Flow, Consolidated Net Income, Consolidated Net 
Worth, Continuing Directors, Disqualified Stock, Equity Interests, Existing 
Indebtedness, Fixed Charge Coverage Ratio, Fixed Charges, Hedging 
Obligations, Hospital, Hospital Swap, Indebtedness, International 
Subsidiaries, Investment Grade, Investments, Lien, Metrocrest Letter of 
Credit Facility, Moody's, Net Income, Net Proceeds, Non-Cash Consideration, 
Non-Recourse Debt, Performance Investment Plan, Permitted Collateral, 
Permitted Liens, Permitted Refinancing Indebtedness, Physician Joint Venture 
Distributions, Physician Support Obligations, Qualified Equity Interests, 
Rating Agencies, Rating Category, Rating Date, Rating Decline, Refinancing, 
Related Business, Restricted Investment, Senior Asset Sale Offer, S&P, 
Specified Assets, Stockholders Equity, Senior 

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Subordinated Notes, Senior Subordinated Note Indenture, Specified Exchange, 
2005 Exchangeable Subordinated Notes, Senior Notes, Senior Note Indenture, 
Transfer Restriction and Wholly Owned Subsidiary.

     SECTION II.2   AMENDMENT TO SECTION 1.02.

     The following definitions are hereby deleted from Section 1.02 of the 
Indenture:  Affiliate Transaction, Change of Control Offer, Change of Control 
Payment, Change of Control Payment Date, Purchase Date, Restricted Payments 
and Senior Subordinated Asset Sale Offer.

     SECTION II.3   AMENDMENT TO SECTION 4.04.

     Clause (ii) of Section 4.04 of the Indenture is hereby amended to read 
in its entirety as follows:

     "(ii) [Intentionally Omitted]"

     SECTION II.4   AMENDMENT TO SECTION 4.05.

     Section 4.05 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.05       TAXES.

     [Intentionally Omitted]"

     SECTION II.5   AMENDMENT TO SECTION 4.07.

     Section 4.07 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.07       LIMITATIONS ON RESTRICTED PAYMENTS.

     [Intentionally Omitted]"

     SECTION II.6   AMENDMENT TO SECTION 4.08.


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     Section 4.08 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.08       LIMITATIONS ON DIVIDEND AND OTHER PAYMENT RESTRICTIONS
                    AFFECTING SUBSIDIARIES.

     [Intentionally Omitted]"

     SECTION II.7   AMENDMENT TO SECTION 4.09.

     Section 4.09 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.09       LIMITATIONS  ON INCURRENCE OF INDEBTEDNESS AND ISSUANCE OF
                    PREFERRED STOCK.

     [Intentionally Omitted]"

     SECTION II.8   AMENDMENT TO SECTION 4.11.

     Section 4.11 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.11       LIMITATIONS ON TRANSACTIONS WITH AFFILIATES.

     [Intentionally Omitted]"

     SECTION II.9   AMENDMENT TO SECTION 4.12.

     Section 4.12 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.12       LIMITATIONS ON LIENS.

     [Intentionally Omitted]"

     SECTION II.10  AMENDMENT TO SECTION 4.13.


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     Section 4.13 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.13       CHANGE OF CONTROL.

     [Intentionally Omitted]"

     SECTION II.11  AMENDMENT TO SECTION 4.14.

     Section 4.14 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.14       CORPORATE EXISTENCE.

     [Intentionally Omitted]"

     SECTION II.12  AMENDMENT TO SECTION 4.15.

     Section 4.15 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.15       LINES OF BUSINESS.

     [Intentionally Omitted]"

     SECTION II.13  AMENDMENT TO SECTION 4.16.

     Section 4.16 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 4.16       LIMITATIONS ON ISSUANCES OF GUARANTEES OF INDEBTEDNESS BY
                    SUBSIDIARIES.

     [Intentionally Omitted]"

     SECTION II.14  AMENDMENT TO SECTION 4.17.

     Section 4.17 of the Indenture is hereby amended to read in its entirety 
as follows:

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"SECTION 4.17       NO SENIOR SUBORDINATED DEBT.

     [Intentionally Omitted]"

     SECTION II.15  AMENDMENT TO SECTION 5.01.

     Section 5.01 of the Indenture is hereby amended to read in its entirety 
as follows:

"SECTION 5.01       LIMITATIONS ON MERGERS, CONSOLIDATIONS OR SALES OF ASSETS.

     The Company may not consolidate or merge with or into (whether or not 
the Company is the surviving corporation), or sell, assign, transfer, lease, 
convey or otherwise dispose of all or substantially all of its properties or 
assets in one or more related transactions to another corporation, Person or 
entity unless:

                  (i)      the Company is the surviving corporation or the 
                           entity or the Person formed by or surviving any such
                           consolidation or merger (if other than the Company) 
                           or to which such sale, assignment, transfer, lease, 
                           conveyance or other disposition shall have been made 
                           is a corporation organized or existing under the laws
                           of the United States, any state thereof or the 
                           District or Columbia;

                  (ii)     the entity or Person formed by or surviving any such 
                           consolidation or merger (if other than the Company) 
                           or the entity or Person to which such sale, 
                           assignment, transfer, lease, conveyance or other 
                           disposition shall have been made assumes all the 
                           Obligations of the Company under this Indenture and 
                           the Securities pursuant to a supplemental
                           indenture in a form reasonably satisfactory to the 
                           Trustee; and

                  (iii)    immediately after such transaction no Default or 
                           Event of Default exists. 

     The Company shall deliver to the Trustee prior to the consummation of 
the proposed transaction an Officers' Certificate to the foregoing effect and 
an Opinion of Counsel, covering clauses (i) through (iii) above, stating that 
the proposed transaction and such supplemental indenture comply with this 
Indenture. The Trustee shall be entitled to conclusively rely upon such 
Officers' Certificate and Opinion of Counsel."

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                                 ARTICLE III

             NOTICE, ENDORSEMENT AND CHANGE OF FORM OF SECURITIES

     SECTION III.1  NOTICE TO SECURITYHOLDERS.

     After the Effective Date, the Company shall mail to Securityholders a 
notice briefly describing the Amendments in accordance with Section 8.02 of 
the Indenture.

     SECTION III.2  NOTATION ON SECURITIES.

     Securities authenticated and delivered after the Effective Date shall, 
at the Company's expense, be affixed by the Trustee with the following 
notation:

                  "The Company and the Trustee have entered into a Third
         Supplemental Indenture, dated as of May 7, 1998, which deleted
         substantially all of the restrictive covenants in the Securities.
         Reference is hereby made to such Third Supplemental Indenture, copies
         of which are on file with The Bank of New York, as Trustee."

     The Trustee may, but shall not be required to, require holders of Securi 
ties authenticated and delivered prior to the Effective Date to deliver such 
Securities to the Trustee so that the Trustee may affix them with the 
aforementioned notation.
                                       
                                   * * * * *

     This Third Supplemental Indenture may be executed in counterparts, each 
of which when so executed shall be deemed to be an original, but all such 
counter parts shall together constitute but one and the same instrument.

Dated as of May 7, 1998

                                      TENET HEALTHCARE CORPORATION



                                      By: /s/ STEPHEN D. FARBER
                                         ----------------------------
                                          Name:    Stephen D. Farber
                                          Title:   Vice President


                                  THE BANK OF NEW YORK,
                                  AS TRUSTEE


                                      By: /s/ MARY LA GUMINA
                                         ----------------------------
                                          Name:    Mary La Gumina
                                          Title:   Assistant Vice President





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