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                                                                     EXHIBIT 3.6


                                 THIRD AMENDMENT
                                     TO THE
               AMENDED AND RESTATED LIMITED PARTNERSHIP AGREEMENT
                                       OF
                        DODGE CITY HEALTHCARE GROUP, L.P.

         THIS THIRD AMENDMENT TO THE AMENDED AND RESTATED LIMITED PARTNERSHIP
AGREEMENT OF DODGE CITY HEALTHCARE GROUP, L.P. ("Amendment") is made and entered
into as of November 4, 1999, by and among Dodge City Healthcare Partner, Inc., a
Kansas corporation and successor in interest to Columbia/HCA of Dodge City,
Inc., as general partner (the "General Partner"), Western Plains Regional
Hospital, LLC, a Delaware limited liability company and a limited partner of the
Partnership (as such term is hereinafter defined) ("Western Plains"), and Dodge
City Outpatient Surgical Facility, Inc., a Kansas corporation and a limited
partner of the Partnership ("Dodge City Limited Partner" and, together with
Western Plains, the "Limited Partners").

                                R E C I T A L S:

         WHEREAS, the General Partner and the Limited Partners are parties to
that certain Amended and Restated Limited Partnership Agreement of Dodge City
Healthcare Group, L.P., dated March 1, 1995, as amended by that certain
Amendment to Article 6.1 of Limited Partnership Agreement dated June 13, 1997,
and that certain Second Amendment to the Amended and Restated Limited
Partnership Agreement of Dodge City Healthcare Group, L.P. dated as of April 8,
1999 (the "Agreement"), all of which relate to Dodge City Healthcare Group, L.P.
(the "Partnership"); and

         WHEREAS, in connection with a corporate restructuring (the "Spin-Off")
of Columbia/HCA Healthcare Corporation ("Columbia"), the General Partner and
Western Plains became affiliates of LifePoint;

         WHEREAS, LifePoint and the LifePoint Affiliates incurred the LifePoint
Debt (as hereinafter defined) at the time of the Spin-Off and, pursuant to the
terms of the LifePoint Debt, the LifePoint Affiliates were required to execute
and deliver, to the maximum extent possible, full guarantees of the LifePoint
Debt and LifePoint was required to pledge, to the maximum extent possible, all
of the assets of the LifePoint Affiliates;

         WHEREAS, the Agreement, prior to this Amendment, would not permit the
General Partner to pledge all of the assets of the Partnership or to cause the
Partnership to execute a full guarantee of the LifePoint Debt (the "Partnership
Limitations") and, as a result, Columbia has agreed to act as guarantor of the



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LifePoint Debt to the extent actually necessary, due to the Partnership
Limitations, to fully guarantee the LifePoint Debt (the "Columbia Guarantee");

         WHEREAS, in consideration for the issuance of the Columbia Guarantee,
Columbia will charge LifePoint a significant fee;

         WHEREAS, following arms-length discussions, in connection with the
execution of this Amendment, the Dodge City Limited Partner has received payment
of $1,000,000, which amount the parties have agreed is intended to compensate
the Dodge City Limited Partner, and which constitutes adequate consideration,
for the anticipated decrease in the value of the investment of the Dodge City
Limited Partner in the Partnership, as well as for any other investment risk to
the Dodge City Limited Partner associated with the Amendment or the Actions (as
such term is hereinafter defined); and

         WHEREAS, the General Partner and the Limited Partners desire to amend
the Agreement as set forth in this Amendment, pursuant to Section 18.8 of the
Agreement.

         NOW, THEREFORE, in consideration of the foregoing and the respective
covenants and agreements contained herein, the sufficiency of which is hereby
acknowledged, the parties hereby agree and consent to the following:

                               A G R E E M E N T:

1. Amendment to Section 8.1(a) of the Agreement. The Agreement is hereby amended
by deleting the text of Section 8.1(a) in its entirety and substituting in
replacement thereof the following:

                  (a) Incur debt and borrow money in any amount and from any
         source, and/or guarantee the repayment and full performance of any debt
         or debts of LifePoint or any LifePoint affiliate, and, if security is
         required therefor or to secure the debts of the General Partner,
         LifePoint or any LifePoint Affiliate, to mortgage, encumber, pledge or
         subject to any other security device its interest in the Partnership
         (including its General Partner interest) or all or any portion of the
         Partnership's property, to obtain replacements of any mortgage,
         encumbrance, pledge or other security device, and to prepay, in whole
         or in part, refinance, increase, modify, consolidate or extend any
         mortgage, encumbrance, pledge or other security device, all of the
         foregoing at such terms and in such amounts as the General Partner
         deems appropriate;

2. Amendment to Section 8.4(c) of the Agreement. The Agreement is hereby amended
by deleting the text of Section 8.4(c) in its entirety and substituting in
replacement thereof the following:



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         Sell, exchange, lease, assign or otherwise transfer more than five
         percent (5%) of the assets of the Partnership (as determined from
         audited financial statements of the Partnership as of the close of
         business of the immediately preceding fiscal year of the Partnership),
         excluding (i) the Actions, (ii) sales of used or obsolete equipment in
         the ordinary course of business, (iii) the grant of pledges, liens
         and/or security interests, and (iv) any transfer as a result of the
         enforcement of any pledge, lien and/or security interest.

3. Deletion of Section 8.4(e) of the Agreement. The Agreement is hereby further
amended by deleting Section 8.4(e) of the Agreement in its entirety and
substituting in replacement thereof the following:

                  (e) Intentionally deleted;

4. Consent of Limited Partners. The Limited Partners hereby expressly agree and
acknowledge that the purpose of this Amendment is to revise the Agreement to
permit the General Partner, for and on behalf of the Partnership, to (a) execute
and deliver a full, unconditional guarantee (on a joint and several basis with
LifePoint and other LifePoint Affiliates) of the obligations of LifePoint and
the LifePoint Affiliates under LifePoint's $150,000,000 Senior Subordinated
Notes due 2009 and all existing and future senior indebtedness of LifePoint and
the LifePoint Affiliates including, without limitation, LifePoint's Credit
Agreement dated May 11, 1999, as the same may be modified or amended from time
to time without notice to the Limited Partners (the "LifePoint Debt"), and (b)
to pledge all of the assets of the Partnership to secure such obligations under
the LifePoint Debt (the "Actions"). Further, the Limited Partners hereby
expressly authorize and consent to the taking of the actions by the General
Partner, for and on behalf of the Partnership (and any other actions necessary
or appropriate to further evidence, secure or permit LifePoint and/or the
LifePoint Affiliates to fully perform their obligations under the LifePoint
Debt).

5. Requisite Approval. Upon execution and delivery of the Amendment by the
parties hereto, which parties represent Partners owning the requisite percentage
of the issued and outstanding Units of any Class set forth in Sections 1.8 and
18.8 of the Agreement, the parties hereto expressly agree that this Amendment
shall constitute and be deemed to be an amendment to, and part of, the
Agreement.

6. No Other Changes. Except as expressly set forth or contemplated in this
Amendment, the terms and conditions of the Agreement shall remain in place and
shall not be altered, amended or changed in any manner whatsoever, except by any
further amendment to the Agreement made in accordance with the terms of the
Agreement, as hereby amended.



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7. No Requirement to Refer. The parties agree that nothing contained in the
Agreement or this Amendment is intended to induce any party to generate
referrals to the Hospital.

8. Counterparts. This Amendment may be executed in any number of counterparts
and by the different parties hereto on separate counterparts, each of which when
executed and delivered shall be deemed an original effective for binding the
parties hereto, but all of which shall together constitute one and the same
instrument.

9. Defined Terms. Capitalized terms used herein without definition shall have
the same meanings ascribed to such terms in the Agreement.

10. Governing Law. This Amendment shall be governed by, and construed in
accordance with, the substantive federal laws of the United States and the laws
of the State of Kansas, and the courts of competent jurisdiction, federal and
state, sitting in such State shall be the exclusive courts of jurisdiction, and
more particularly the federal courts in Wichita, Kansas, for venue purposes and
for litigation or other proceedings as between the parties that may be brought,
or arise out of, or by reason of this Amendment.




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         IN WITNESS WHEREOF, the parties hereto have executed this Amendment No.
3 to Amended and Restated Limited Partnership Agreement of Dodge City Healthcare
Group, L.P., and hereby consent to the amendment and modification of the
Agreement provided herein as of the date first above written.

                                   GENERAL PARTNER:

                                   Dodge City Healthcare Partner, Inc.


                                   By:
                                       -----------------------------------------
                                   Name:
                                         ---------------------------------------
                                   Title:
                                          --------------------------------------


                                   LIMITED PARTNERS:

                                   Western Plains Regional Hospital, LLC


                                   By:
                                       -----------------------------------------
                                   Name:
                                         ---------------------------------------
                                   Title:
                                          --------------------------------------



                                   Dodge City Outpatient Surgery Facility, Inc.


                                   By:
                                       -----------------------------------------
                                   Name:
                                         ---------------------------------------
                                   Title:
                                          --------------------------------------



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