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                                                                   EXHIBIT 10.50


                 FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT


         THIS FIRST AMENDMENT (this "Amendment"), made this 29th day of March,
2001, is by and among Bank of America, N.A., (the "Bank"), DeLand Surgery
Center, Ltd., a Florida limited partnership (the "Borrower") and Symbion
Ambulatory Resource Centres, Inc., a Tennessee corporation (the "Guarantor").

                                    RECITALS

         Bank, Borrower and Guarantor are parties to a Loan and Security
Agreement dated October 3, 2000 (as amended from time to time, the "Loan
Agreement"). Capitalized terms not otherwise defined in this Amendment shall
have the meaning provided in the Loan Agreement. Borrower has requested that
Bank make certain changes to the Loan Agreement, and the Bank is willing to do
so, subject, among other things, to the execution of this Amendment and
compliance with the terms hereof.

         NOW, THEREFORE, the parties to this Amendment hereby agree as follows:

Article I.  Amendment to Loan Agreement. The parties hereto amend the Loan
Agreement as follows:

         Section 1.1 Section 6.15(d) of the Loan Agreement is hereby deleted in
its entirety and replaced with the following:

                  "(d) At all times on and after December 31, 2000, the
         Shareholders' Equity of Symbion, calculated on a consolidated basis,
         shall be greater than the sum of (1) ninety percent (90%) of the
         shareholder's equity of Symbion at December 31, 2000, plus (2)
         eighty-five percent (85%) of the sum of (a) the aggregate amount of
         equity capital contributed to Symbion after December 31, 2000, plus (b)
         the aggregate cumulative positive net income (without deduction for any
         negative net income) of Symbion after December 31, 2000, all computed
         in accordance with GAAP;"

Article II.  General.

         Section 2.1 Loan Agreement. Except as amended hereby, the provisions of
the Loan Agreement shall remain in full force and effect. References in the Loan
Agreement and the other Loan Documents shall be references to the Loan Agreement
as amended by this Amendment.

         Section 2.2 Governing Law. This Amendment shall be governed by and
construed in accordance with the laws of the State of Tennessee without
reference to its choice of law rules.


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         Section 2.3 Execution in Counterparts. This Amendment may be executed
in one or more counterparts, each of which shall be considered an original
instrument, but all of which shall be considered one and the same agreement, and
shall become binding when one or more counterparts have been signed by each of
the parties and delivered to each of the parties.

         Section 2.4 Representations. Borrower hereby makes the following
representations and warranties:

                  (a) as of the date hereof, Borrower has no defense against
payment of any or all of the Obligations;

                  (b) as of the date hereof, no Event of Default or Unmatured
Default has occurred or is continuing (after giving effect to this Amendment).


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


BANK:                                    BORROWER:

BANK OF AMERICA, N.A.                    DELAND SURGERY CENTER, LTD.,
                                         a Florida Limited Partnership

                                             By:  Surgicare of DeLand, Inc.,
                                                  its General Partner


BY:    /s/ Sandy Hamrick                 BY:    /s/ Charles T. Neal
       ---------------------------              --------------------------------

TITLE: Senior Vice President             TITLE: President and CEO
       ---------------------------              --------------------------------

                                         BY:    /s/ Ronald L. Brank
                                                --------------------------------

                                         TITLE: CFO, Secretary and Sr. VP
                                                --------------------------------


                                         GUARANTOR:

                                         SYMBION AMBULATORY RESOURCE
                                         CENTRES, INC.


                                         BY:    /s/ Ronald L. Brank
                                                --------------------------------

                                         TITLE: CFO, Secretary and Sr. VP
                                                --------------------------------

                                         BY:    /s/ Charles T. Neal
                                                --------------------------------

                                         TITLE: President and CEO
                                                --------------------------------



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