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                                                                   EXHIBIT 10.27


                SECOND AMENDMENT TO LOAN AND SECURITY AGREEMENT

         THIS SECOND AMENDMENT (this "Amendment"), made this 29th day of March,
2001, is by and among Bank of America, N.A. (the "Bank"), ARC Worcester Center,
L.P., a Tennessee limited partnership (the "Borrower") and Symbion Ambulatory
Resource Centres, Inc., a Tennessee corporation (the "Guarantor").

                                    RECITALS

         Bank has previously made a loan to the Borrower, an Affiliate of
Guarantor, pursuant to a Loan and Security Agreement dated November 9, 1999 (as
amended from time to time, the "Loan Agreement"). The Loan Agreement has been
amended pursuant to a First Amendment to Loan and Security Agreement dated
April 12, 2000 among Bank, Borrower and Guarantor. 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


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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.

         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.               ARC WORCESTER CENTER, L.P., a Tennessee
                                    Limited Partnership

BY: /s/ Sandra Hamrick              By: Ambulatory Resource Centres of
   ----------------------           Massachusetts, Inc., its General Partner

TITLE: Sr. 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/ Ronald L. Brank
                                       -----------------------------------------
                                    TITLE: CFO, Secretary and Sr. Vice President
                                          --------------------------------------
                                    BY: /s/ Charles T. Neal
                                       -----------------------------------------
                                    TITLE: President and Chief Executive Officer
                                          --------------------------------------


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