Exhibit 3.168

SINGLE MEMBER OPERATING AGREEMENT

OPERATING AGREEMENT
OF
UNIPHY HEALTHCARE OF JOHNSON CITY VI, LLC

Members

	Aggregate Percentage Interest				Cash Contributed or Agreed Value of Other Property or
Name, Address, SSN	Financial		Governance		Services Contributed
Symbion, Inc. 40 Burton Hills Blvd. Suite 500 Nashville, Tennessee 37215 FEIN: 62-1625480	100	%	100	%	$

ATTEST: The above information is true,
complete and correct this the 29 day of
December, 2004.

/s/ R. Dale Kennedy

Secretary

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SINGLE MEMBER OPERATING AGREEMENT

UNIPHY HEALTHCARE OF JOHNSON CITY VI, LLC
OPERATING AGREEMENT

Parties to Contribution Agreements

Name, Address, SS# Class of Membership Interest
and Percentage Interest to be
Acquired Amount of Cash or Value of
Property or Services Required to
be Contributed Time at Which Contribution is
Required to be Made

ATTEST: The above information is true,
complete and correct this the 29 day of
December, 2004.

/s/ R. Dale Kennedy

Secretary

2

SINGLE MEMBER OPERATING AGREEMENT

UNIPHY HEALTHCARE OF JOHNSON CITY VI, LLC
OPERATING AGREEMENT

Parties to Contribution Allowance Agreements

Name, Address, SS# Class of Membership Interest 
and Percentage Interest Able 
to be Acquired Amount of Cash or Value of Property
or Services that must be Contributed to 
Acquire Interest Time at Which 
Contribution is to be 
Made

ATTEST: The above information is true,
complete and correct this the 29 day of
December, 2004.

/s/ R. Dale Kennedy

Secretary

3

SINGLE MEMBER OPERATING AGREEMENT

UNIPHY HEALTHCARE OF JOHNSON CITY VI, LLC
OPERATING AGREEMENT

Assignees of Financial Rights

Name, Address, SS# Name of 
Assignor Amount of Financial Rights Assigned

ATTEST: The above information is true,
complete and correct this the 29 day of
December, 2004.

/s/ R. Dale Kennedy

Secretary

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SINGLE MEMBER OPERATING AGREEMENT

UNIPHY HEALTHCARE OF JOHNSON CITY VI, LLC
OPERATING AGREEMENT

Managers

Chief Manager and President:	Gregg Stanley
Chief Financial Officer
Secretary and Treasurer:	Darrell Naish
Chief Development Officer
and Sr. Vice President:	William V. B. Webb
Vice President	Kenneth C. Mitchell
Governors:	Clifford G. Adlerz
	R. Dale Kennedy
	Kenneth C. Mitchell
Principal Executive Office:	40 Burton Hills Blvd.
	Suite 500
	Nashville, Tennessee 37215

Except as provided herein, the LLC shall be controlled by the default rules of the Act and the provisions of the Articles. The LLC shall be board-managed. The Membership Interests (Financial Rights and Governance Rights) are as set forth herein. In order to make a distribution greater than the amount required to pay federal income taxes on the income of the LLC, all distributions shall require the consent of a majority of the Governors. There shall, to the extent reasonably possible, be annual distributions equal to the federal tax on the taxable income of the LLC. Membership Interests and Financial Rights may only be assigned upon the Majority Vote of the Governors. New Members may only be admitted on a Majority Vote of the Governors. For these purposes, “Majority Vote” shall mean a majority of the Governance Rights entitled to vote on the matter, or with respect to Governors, a majority in number of Governors entitled to vote, whether or not present at a meeting. The only dissolution events shall be the having of no Members or a Majority Vote of the Members to dissolve the LLC.

This the 29th day of December, 2004.

SYMBION, INC.
By:	/s/ Kenneth C. Mitchell
Kenneth C. Mitchell
Chief Financial Officer and Senior Vice President of Finance
		ATTEST: The above information is true, complete and correct this the 29 day of December, 2004.
		/s/ R. Dale Kennedy
		Secretary

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