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                                                                   EXHIBIT 10.51


                 SECOND AMENDMENT TO LOAN AND SECURITY AGREEMENT


         THIS SECOND AMENDMENT (this "Amendment"), made as of this 30th 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 by a First Amendment to Loan and
Security Agreement dated March 29, 2001 (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 a loan to an Affiliate of Borrower, 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 The line of text between 8.1(h) and 8.1(i) of the Loan
Agreement is hereby deleted in its entirety and the following is inserted as
8.1(p):

                  "(p) A receiver or trustee shall be appointed for the
         Borrower, Symbion or Guarantor or for any substantial part of their
         respective assets, or any proceedings shall be instituted for the
         dissolution or the full or partial liquidation of the Borrower, Symbion
         or Guarantor, or the Borrower, Symbion or Guarantor shall discontinue
         business or materially change the nature of any of their respective
         businesses."

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:    /s/ Elizabeth L. Knox        Surgicare of DeLand, Inc.,
       ---------------------        its General Partner

TITLE: Senior Vice President        BY:    /s/ Charles T. Neal
       ---------------------               -------------------------------------

                                    TITLE: President and Chief Executive Officer
                                           -------------------------------------

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

                                    TITLE: CFO, Secretary and Sr. Vice President
                                           -------------------------------------


                                    GUARANTOR:

                                    SYMBION AMBULATORY RESOURCE CENTRES, INC.

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

                                    TITLE: President and Chief Executive Officer
                                           -------------------------------------

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

                                    TITLE: CFO, Secretary and Sr. Vice President
                                           -------------------------------------


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