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                                                                    EXHIBIT 4.9

                             SUPPLEMENTAL INDENTURE
                    TO BE DELIVERED BY SUBSEQUENT GUARANTORS

         SUPPLEMENTAL INDENTURE (this "Supplemental Indenture") dated as of
August 1, 2003, among Southeast Texas Hospital, LP (the "Guaranteeing
Subsidiary"), a subsidiary of IASIS Healthcare Corporation (or its successor), a
corporation organized under the laws of Delaware (the "Company"), and The Bank
of New York, as trustee under the indenture referred to below (the "Trustee").

                               W I T N E S S E T H

         WHEREAS, the Company has heretofore executed and delivered to the
Trustee an indenture (the "Indenture"), dated as of October 15, 1999, providing
for the issuance of an aggregate principal amount at maturity of $230.0 million
of 13% Senior Subordinated Notes due 2009 (the "Notes");

         WHEREAS, the Indenture provides that under certain circumstances the
Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental
indenture pursuant to which the Guaranteeing Subsidiary shall unconditionally
guarantee all of the Company's Obligations under the Notes and the Indenture on
the terms and conditions set forth herein (the "Subsidiary Guarantee"); and

         WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the
Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

         1.       Capitalized Terms. Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

         2.       Agreement to Guarantee. The Guaranteeing Subsidiary hereby
agrees as follows:

                  (a)      Along with all Guarantors named in the Indenture, to
                           jointly and severally Guarantee to each Holder of a
                           Note authenticated and delivered by the Trustee and
                           to the Trustee and its successors and assigns,
                           irrespective of the validity and enforceability of
                           the Indenture, the Notes or the obligations of the
                           Company hereunder or thereunder, that:

                                    (i)      the principal of and interest on
                                             the Notes will be promptly paid in
                                             full when due, whether at maturity,
                                             by acceleration, redemption or
                                             otherwise, and interest on the
                                             overdue principal of and interest
                                             on the Notes, if any, if lawful,
                                             and all other obligations of the
                                             Company to the Holders or the

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                                             Trustee hereunder or thereunder
                                             will be promptly paid in full or
                                             performed, all in accordance with
                                             the terms hereof and thereof; and

                                    (ii)     in case of any extension of time of
                                             payment or renewal of any Notes or
                                             any of such other obligations, that
                                             same will be promptly paid in full
                                             when due or performed in accordance
                                             with the terms of the extension or
                                             renewal, whether at stated
                                             maturity, by acceleration or
                                             otherwise. Failing payment when due
                                             of any amount so guaranteed or any
                                             performance so guaranteed for
                                             whatever reason, the Guarantors
                                             shall be jointly and severally
                                             obligated to pay the same
                                             immediately.

                  (b)      The obligations hereunder shall be unconditional,
                           irrespective of the validity, regularity or
                           enforceability of the Notes or the Indenture, the
                           absence of any action to enforce the same, any waiver
                           or consent by any Holder of the Notes with respect to
                           any provisions hereof or thereof, the recovery of any
                           judgment against the Company, any action to enforce
                           the same or any other circumstance which might
                           otherwise constitute a legal or equitable discharge
                           or defense of a guarantor.

                  (c)      The following is hereby waived: diligence
                           presentment, demand of payment, filing of claims with
                           a court in the event of insolvency or bankruptcy of
                           the Company, any right to require a proceeding first
                           against the Company, protest, notice and all demands
                           whatsoever.

                  (d)      This Subsidiary Guarantee shall not be discharged
                           except by complete performance of the obligations
                           contained in the Notes and the Indenture.

                  (e)      If any Holder or the Trustee is required by any court
                           or otherwise to return to the Company, the
                           Guarantors, or any Custodian, Trustee, liquidator or
                           other similar official acting in relation to either
                           the Company or the Guarantors, any amount paid by
                           either to the Trustee or such Holder, this Subsidiary
                           Guarantee, to the extent theretofore discharged,
                           shall be reinstated in full force and effect.

                  (f)      The Guaranteeing Subsidiary shall not be entitled to
                           any right of subrogation in relation to the Holders
                           in respect of any obligations guaranteed hereby until
                           payment in full of all obligations guaranteed hereby.

                  (g)      As between the Guarantors, on the one hand, and the
                           Holders and the Trustee, on the other hand, (x) the
                           maturity of the obligations guaranteed hereby may be
                           accelerated as provided in Article 6 of the Indenture
                           for the purposes of this Subsidiary Guarantee,
                           notwithstanding any stay,

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                           injunction or other prohibition preventing such
                           acceleration in respect of the obligations guaranteed
                           hereby, and (y) in the event of any declaration of
                           acceleration of such obligations as provided in
                           Article 6 of the Indenture, such obligations (whether
                           or not due and payable) shall forthwith become due
                           and payable by the Guarantors for the purpose of this
                           Subsidiary Guarantee.

                  (h)      The Guarantors shall have the right to seek
                           contribution from any non-paying Guarantor so long as
                           the exercise of such right does not impair the rights
                           of the Holders under the Guarantee.

                  (i)      The obligations hereunder shall be subject to the
                           subordination provisions of the Indenture.

         3.       Execution and Delivery. Each Guaranteeing Subsidiary agrees
that the Subsidiary Guarantees shall remain in full force and effect
notwithstanding any failure to endorse on each Note a notation of such
Subsidiary Guarantee.

         4.       Guaranteeing Subsidiary May Consolidate, Etc. on Certain
                  Terms.

                  (a)      The Guaranteeing Subsidiary may not consolidate with
                           or merge with or into (whether or not such Guarantor
                           is the surviving Person) another corporation, Person
                           or entity whether or not affiliated with such
                           Guarantor unless:

                                    (i)      subject to Section 11.05 of the
                                             Indenture, the Person formed by or
                                             surviving any such consolidation or
                                             merger (if other than a Guarantor
                                             or the Company) unconditionally
                                             assumes all the obligations of such
                                             Guarantor, pursuant to a
                                             supplemental indenture in form and
                                             substance reasonably satisfactory
                                             to the Trustee, under the Notes,
                                             the Indenture and the Subsidiary
                                             Guarantee on the terms set forth
                                             herein or therein; and

                                    (ii)     immediately after giving effect to
                                             such transaction, no Default or
                                             Event of Default exists.

                  (b)      In case of any such consolidation, merger, sale or
                           conveyance and upon the assumption by the successor
                           corporation, by supplemental indenture, executed and
                           delivered to the Trustee and satisfactory in form to
                           the Trustee, of the Subsidiary Guarantee endorsed
                           upon the Notes and the due and punctual performance
                           of all of the covenants and conditions of the
                           Indenture to be performed by the Guarantor, such
                           successor corporation shall succeed to and be
                           substituted for the Guarantor with the same effect as
                           if it had been named herein as a Guarantor. Such
                           successor corporation thereupon may cause to be
                           signed any or all of the Subsidiary Guarantees

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                           to be endorsed upon all of the Notes issuable
                           hereunder which theretofore shall not have been
                           signed by the Company and delivered to the Trustee.
                           All the Subsidiary Guarantees so issued shall in all
                           respects have the same legal rank and benefit under
                           the Indenture as the Subsidiary Guarantees
                           theretofore and thereafter issued in accordance with
                           the terms of the Indenture as though all of such
                           Subsidiary Guarantees had been issued at the date of
                           the execution hereof.

                  (c)      Except as set forth in Articles 4 and 5 of the
                           Indenture, and notwithstanding clauses (a) and (b)
                           above, nothing contained in the Indenture or in any
                           of the Notes shall prevent any consolidation or
                           merger of a Guarantor with or into the Company or
                           another Guarantor, or shall prevent any sale or
                           conveyance of the property of a Guarantor as an
                           entirety or substantially as an entirety to the
                           Company or another Guarantor.

         5.       Releases.

                  (a)      In the event of a sale or other disposition of all of
                           the assets of any Guarantor, by way of merger,
                           consolidation or otherwise, or a sale or other
                           disposition of all to the capital stock of any
                           Guarantor, then such Guarantor (in the event of a
                           sale or other disposition, by way of merger,
                           consolidation or otherwise, of all of the capital
                           stock of such Guarantor) or the corporation acquiring
                           the property (in the event of a sale or other
                           disposition of all or substantially all of the assets
                           of such Guarantor) will be released and relieved of
                           any obligations under its Subsidiary Guarantee;
                           provided that the Net Proceeds of such sale or other
                           disposition are applied in accordance with the
                           applicable provisions of the Indenture, including
                           without limitation Section 4.10 of the Indenture.
                           Upon delivery by the Company to the Trustee of an
                           Officers' Certificate and an Opinion of Counsel to
                           the effect that such sale or other disposition was
                           made by the Company in accordance with the provisions
                           of the Indenture, including without limitation
                           Section 4.10 of the Indenture, the Trustee shall
                           execute any documents reasonably required in order to
                           evidence the release of any Guarantor from its
                           obligations under its Subsidiary Guarantee.

                  (b)      Any Guarantor not released from its obligations under
                           its Subsidiary Guarantee shall remain liable for the
                           full amount of principal of and interest on the Notes
                           and for the other obligations of any Guarantor under
                           the Indenture as provided in Article 11 of the
                           Indenture.

         6.       No Recourse Against Others. No past, present or future
director, officer, employee, incorporator, stockholder or agent of the
Guaranteeing Subsidiary, as such, shall have any liability for any obligations
of the Company or any Guaranteeing Subsidiary under the Notes, any Subsidiary
Guarantees, the Indenture or this Supplemental Indenture or for any claim based
on, in respect of, or by reason of, such obligations or their creation. Each
Holder of the

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Notes by accepting a Note waives and releases all such liability. The waiver and
release are part of the consideration for issuance of the Notes. Such waiver may
not be effective to waive liabilities under the federal securities laws and it
is the view of the SEC that such a waiver is against public policy.

         7.       NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW
YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE BUT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT
THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED
THEREBY.

         8.       Counterparts. The parties may sign any number of copies of
this Supplemental Indenture. Each signed copy shall be an original, but all of
them together represent the same agreement.

         9.       Effect of Headings. The Section headings herein are for
convenience only and shall not affect the construction hereof.

         10.      The Trustee. The Trustee shall not be responsible in any
manner whatsoever for or in respect of the validity or sufficiency of this
Supplemental Indenture or for or in respect of the recitals contained herein,
all of which recitals are made solely by the Guaranteeing Subsidiary and the
Company.

         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.

         Dated: August 1, 2003

                                    SOUTHEAST TEXAS HOSPITAL, LP

                                    By:  IASIS HEALTHCARE HOLDINGS, INC.,
                                             as General Partner

                                    By: -s- Frank A. Coyle
                                       --------------------------------------
                                    Name: Frank A. Coyle
                                    Title: Secretary

                                    THE BANK OF NEW YORK,
                                         as Trustee

                                    By: -s- Robert A. Massimillo
                                    ------------------------------------------
                                    Name: Robert A. Massimillo
                                    Title: Vice President

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         IN WITNESS WHEREOF, the undersigned have caused this Supplemental
Indenture, dated as of August 1, 2003, among Southeast Texas Hospital, LP, as
Guaranteeing Subsidiary, and The Bank of New York, as Trustee, to be duly
executed and attested.

                                 MEMORIAL HOSPITAL OF TAMPA, LP
                                 MESA GENERAL HOSPITAL, LP
                                 ODESSA REGIONAL HOSPITAL, LP
                                 PALMS OF PASADENA HOSPITAL, LP
                                 SOUTHWEST GENERAL HOSPITAL, LP
                                 ST. LUKE'S BEHAVIORAL HOSPITAL, LP
                                 ST. LUKE'S MEDICAL CENTER, LP
                                 TEMPE ST. LUKE'S HOSPITAL, LP
                                 TOWN & COUNTRY HOSPITAL, LP
                                 JORDAN VALLEY HOSPITAL, LP
                                 DAVIS HOSPITAL & MEDICAL CENTER, LP

                                 By: IASIS HEALTHCARE HOLDINGS, INC.,
                                         as General Partner

                                 By: -s- Frank A. Coyle
                                    --------------------------------------
                                 Name: Frank A. Coyle
                                 Title: Secretary

                                 IASIS HEALTHCARE CORPORATION
                                 ARIZONA DIAGNOSTIC & SURGICAL CENTER, INC.
                                 BAPTIST JOINT VENTURE HOLDINGS, INC.
                                 BEAUMONT HOSPITAL HOLDINGS, INC.
                                 BILTMORE SURGERY CENTER HOLDINGS, INC.
                                 CLINICARE OF UTAH, INC.
                                 DAVIS HOSPITAL HOLDINGS, INC.
                                 DAVIS SURGICAL CENTER HOLDINGS, INC.
                                 FIRST CHOICE PHYSICIANS NETWORK HOLDINGS, INC.
                                 HEALTH CHOICE ARIZONA, INC.
                                 IASIS HEALTHCARE HOLDINGS, INC.
                                 IASIS MANAGEMENT COMPANY
                                 JORDAN VALLEY HOSPITAL HOLDINGS, INC.
                                 METRO AMBULATORY SURGERY CENTER, INC.
                                 PIONEER VALLEY HEALTH PLAN, INC.
                                 PIONEER VALLEY HOSPITAL, INC.
                                 ROCKY MOUNTAIN MEDICAL CENTER, INC.
                                 SALT LAKE REGIONAL MEDICAL CENTER, INC.
                                 IASIS HOSPITAL NURSE STAFFING COMPANY
                                 SOUTHRIDGE PLAZA HOLDINGS, INC.
                                 SSJ ST. PETERSBURG HOLDINGS, INC.

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                                 BROOKWOOD DIAGNOSTIC CENTER OF TAMPA, INC.
                                 IASIS PHYSICIAN SERVICES, INC.
                                 CLINICARE OF TEXAS, INC.
                                 IASIS FINANCE, INC.
                                 IASIS HOME INFUSION AND MEDICAL EQUIPMENT, INC.
                                 IASIS TRANSCO, INC.
                                 MCS/AZ, INC.
                                 PALMS OF PASADENA HOMECARE, INC.
                                 TAMPA BAY STAFFING SOLUTIONS, INC.
                                 BILTMORE SURGERY CENTER, INC.

                                 By: -s- Frank A. Coyle
                                    --------------------------------------
                                 Name: Frank A. Coyle
                                 Title: Secretary

                                 IASIS HEALTHCARE MSO SUB OF SALT LAKE CITY, LLC

                                 By: -s- Frank A. Coyle
                                    --------------------------------------
                                 Name: Frank A. Coyle
                                 Title: Secretary

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