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Exhibit 21.1
  STATE OFNAME
    
    INCORPORATION25 East Same Day Surgery, L.L.C.
    
    MOAdvanced Ambulatory Surgical Care, L.P. (doing business as Advanced Surgical Care)
    
    MOAdventist Midwest Health/USP Surgery Centers, L.L.C.
    
    ILAlamo Heights Surgicare, L.P. (doing business as Alamo Heights Surgery Center)
    
    TXAlexandria Surgery Center Real Estate, LLC
    
    LAALMH Surgical Center East, LLC
    
    ILAmerican Endoscopy Services, LLC
    
    TNArlington Orthopedic and Spine Hospital, LLC
    
    TXArlington Surgicare Partners, Ltd. (doing business as Surgery Center of Arlington)
    
    TXAspen Healthcare Holdings, Ltd.
    
    UKAspen Healthcare, Ltd.
    
    UKAspen Leasing, Ltd.
    
    UKAustintown Surgery Center, LLC
    
    OHBaptist Plaza Surgicare, L.P.
    
    TNBaptist Surgery Center, L.P. (doing business as Baptist Ambulatory Surgery Center)
    
    TNBagley Holdings, LLC
    
    OHBallenger Crow Development, LLC
    
    DEBaylor Surgicare at Plano, LLC
    
    TXBeaumont Surgical Affiliates, Ltd.
    
    TXBellaire Outpatient Surgery Center, L.L.P. (doing business as Baylor Surgicare at Oakmont)
    
    TXBon Secours Surgery Center at Harbour View, LLC
    
    VABon Secours Surgery Center at Virginia Beach, LLC
    
    VABriarcliff Ambulatory Surgery Center, L.P. (doing business as Briarcliff Surgery Center)
    
    MOCape Surgery Center, L.P.
    
    FLCedar Park Surgery Center, L.L.P.
    
    TXCentral Avenue Surgery Center, LLC
    
    TNCentral Jersey Surgery Center, LLC
    
    GACentral Virginia Surgi-Center, L.P. (doing business as Surgi-Center of Central Virginia)
    
    VACHC/USP Surgery Centers, LLC
    
    FLChesterfield Ambulatory Surgery Center, L.P. (doing business as Chesterfield Surgery Center)
    
    MOChico Surgery Center, LP
    
    CACHRISTUS Cabrini Surgery Center, L.L.C.
    
    LAChristus Santa Rosa Surgery Center, L.L.P.
    
    TXCHRISTUS Santa Rosa Imaging Centers Partnership, LLC
    
    TXChristus/USP General Partner, LLC
    
    TXChristus/USP Surgery Centers, L.P.
    
    TXCHW/USP Glendale GP, LLC
    
    CACHW/USP Glendale Memorial Surgery Centers, L.L.C.
    
    CACHW/USP Folsom GP, LLC
    
    CACHW/USP Las Vegas Surgery Centers, LLC
    
    NVCHW/USP Oxnard GP, LLC
    
    CACHW/USP Oxnard Surgery Centers, LLC
    
    CACHW/USP Phoenix II, LLC
    
    AZCHW/USP Redding GP, LLC
    
    CACHW/USP Roseville GP, LLC
    
    CACHW/USP Sacramento Surgery Centers, L.L.C.
    
    CACHW/USP San Gabriel GP, L.L.C.
    
    CACHW/USP San Gabriel Surgery Centers, L.L.C.
    
    CACHW/USP Surgery Centers, LLC
    
    AZClarkston ASC Partners, LLC
    
    MICoast Surgery Center, L.P.
    
    CACorpus Christi Holdings, LLC
    
    NVCorpus Christi Surgicare, Ltd. (doing business as CHRISTUS Spohn  Corpus Christi Outpatient Surgery)
    
    TXCourt Street Surgery Center, L.P. (doing business as (1) Court Street Surgery Center and (2) Redding Surgery Center)
    
    CACreekwood Surgery Center, L.P.
    
    MOCS/USP General Partners, LLC
    
    TXCS/USP Surgery Centers, LP
    
    TXDallas Surgical Partners, L.L.P. (doing business as (1) Baylor Surgicare (2) Texas Surgery Center
and (3) Physicians Day
   Surgery)
    
    TXDay-Op Surgery Consulting Company, LLC
    
    DEDenton Surgicare Partners, Ltd. (doing business as Baylor Surgicare at Denton)
    
    TXDenton Surgicare Real Estate, Ltd.
    
    TXDesert Ridge Outpatient Surgery, LLC
    
    AZDesoto Surgicare Partners, Ltd. (doing business as North Texas Surgery Center)
    
    TXDestin Surgery Center, Ltd.
    
    FLDoctors Outpatient Surgicenter, Ltd.
    
    TXDoctors Surgery Center of Kingman, L.L.C.
    
    AZEast Brunswick Surgery Center, LLC
    
    NJEast West Surgery Center, L.P.
    
    GAEastgate Building Center, L.L.C.
    
    OHElmwood Park Same Day Surgery, L.L.C.
    
    ILENH/USP Surgery Centers I, L.L.C.
    
    ILENH/USP Surgery Centers II, L.L.C.
    
    ILFolsom Outpatient Surgery Center, L.P.
    
    CAFort Worth Osteopathic Surgery Center, L.P.
    
    TXFort Worth Osteopathic Surgery Center GP, L.L.C.
    
    TXFort Worth Surgicare Partners, Ltd. (doing business as Baylor Surgical Hospital at Ft. Worth)
    
    TXFrisco Medical Center, L.L.P. (doing business as Baylor Medical Center at Frisco)
    
    TXFrontenac Ambulatory Surgery & Spine Care Center, L.P. (doing business as Frontenac Surgery & Spine Care Center)
    
    MOGarland Surgicare Partners, Ltd. (doing business as Baylor Surgicare at Garland)
    
    TXGeorgia Musculoskeletal Network, Inc.
    
    GAGenesis ASC Partners, LLC (doing business as Genesis Surgery Center)
    
    MI




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Glendale Memorial Ambulatory Surgery Center, L.P.
    
    CAGlobal Healthcare Partners, Ltd.
    
    UKGP Surgery Center, LLC (doing business as Great Plains Ambulatory Surgery Center)
    
    DEGrapevine Surgicare Partners, Ltd. (doing business as Baylor Surgicare at Grapevine)
    
    TXGreater Baton Rouge Surgical Hospital, LLC
    
    LAHealth Horizons of Kansas City, Inc.
    
    TNHealth Horizons of Murfreesboro, Inc.
    
    TNHealth Horizons of Nashville, Inc.
    
    TNHighgate Private Clinic, Ltd.
    
    UKHinsdale Surgical Center, LLC
    
    ILHouston Ambulatory Surgical Associates, L.P.
    
    TXHuguley Surgery Center, LLP (doing business as Doctors Surgery Center at Huguley)
    
    TXICNU Rockford, LLC
    
    ILICNU San Antonio, LLC
    
    TXINTEGRIS/USP Surgery Centers, LLC
    
    OKINTEGRIS/USP Surgery Centers II, L.L.C.
    
    OKIdaho Surgery Center, LLC
    
    IDIrving-Coppell Surgical Hospital, L.L.P.
    
    TXISS-Orlando, LLC
    
    FLKHS/USP Surgery Centers, LLC
    
    NJKHS Ambulatory Surgery Center LLC
    
    NJKSF Orthopaedic Surgery Center, L.L.P.
    
    TXLake County Ambulatory Surgery Center, LLC
    
    ILLake Lansing ASC Partners, LLC (doing business as Lansing Surgery Center)
    
    MILansing ASC Partners, LLC
    
    MILas Cruces Surgical Center LLC
    
    NMLawrenceville Surgery Center, L.L.C.
    
    GALegacy/USP Surgery Centers, L.L.C.
    
    ORLewisville Surgicare Partners, Ltd. (doing business as Baylor Surgicare at Lewisville)
    
    TXLiberty Ambulatory Surgery Center, L.P.
    
    MOLincolnwood Ambulatory Surgery Center, L.P.
    
    ILMadison Ambulatory Surgery Center, LLC
    
    MSManchester Ambulatory Surgery Center, LP (doing business as Manchester Surgery Center)
    
    MOManitowoc Surgery Center, LLC
    
    DEMary Immaculate Ambulatory Surgery Center, LLC
    
    VAMason Ridge Ambulatory Surgery Center, L.P. (doing business as Mason Ridge Surgery Center)
    
    MOMcLaren ASC of Flint, LLC (doing business as Mid-Michigan Surgery & Endoscopy Center)
    
    MIMcLaren Real Estate Partners, Limited Partnership
    
    MIMCSH Real Estate Investors, Ltd.
    
    TXMedcenter Management Services, Inc.
    
    DEMemorial Ambulatory Surgery Center, LLC
    
    VAMemorial Hermann Specialty Hospital Kingwood, L.L.C.
    
    TXMemorial Hermann Surgery Center Katy, LLP
    
    TXMemorial Hermann Surgery Center Northwest LLP
    
    TXMemorial Hermann Surgery Center Pearland, LLP
    
    TXMemorial Hermann Surgery Center Southwest, L.L.P.
    
    TXMemorial Hermann Surgery Center Texas Medical Center, LLP
    
    TXMemorial Hermann Surgery Center Sugar Land, L.L.P.
    
    TXMemorial Hermann Surgery Center  The Woodlands, LLP
    
    TXMemorial Hermann Surgery Center Westside, LLP
    
    TXMemorial Hermann/USP Surgery Centers, LLP
    
    TXMemorial Hermann/USP Surgery Centers II, LP
    
    TXMemorial Hermann/USP Surgery Centers III, LLP
    
    TXMemorial Hermann/USP Surgery Centers IV, LLP
    
    TXMetro Surgery Center, L.P.
    
    DEMetroplex Surgicare Partners, Ltd.
    
    TXMH/USP Kingwood, LLC
    
    TXMichigan ASC Partners, L.L.C.
    
    MIMid Rivers Ambulatory Surgery Center, L.P. (doing business as Mid Rivers Surgery Center)
    
    MOMiddle Tennessee Ambulatory Surgery Center, L.P.
    
    DEMountain Empire Surgery Center, L.P.
    
    GAMSH Partners, LLP (doing business as Mary Shiels Hospital)
    
    TXNew Horizons Surgery Center, LLC
    
    OHNew Mexico Orthopaedic Surgery Center Limited Partnership
    
    GANorth Central Surgical Center, L.L.P.
    
    TXNorth Garland Surgery Center, L.L.P.
    
    TXNorth Shore Same Day Surgery, L.L.C.
    
    ILNKCH/USP Surgery Centers, LLC
    
    MONKCH/USP Surgery Centers II, L.L.C.
    
    MONKCH/USP Briarcliff GP, LLC
    
    MONKCH/USP Liberty GP, LLC
    
    MONortheast Ohio Surgery Center, LLC
    
    OHNorthern Monmouth Regional Surgery Center, L.L.C.
    
    NJNorthridge Surgery Center, L.P.
    
    TNNorthwest Georgia Orthopaedic Surgery Center, LLC (doing business as Northwest Georgia Surgery Center)
    
    GANorthwest Surgery Center, Ltd.
    
    TXNorthwest Surgery Center, LLP
    
    TXOklahoma Center for Orthopedic and Multi-Specialty Surgery, LLC
    
    OKOlive Ambulatory Surgery Center, L.P. (doing business as Olive Surgery Center)
    
    MOOpthalmology Anesthesia Services, LLC
    
    FLOrlando Opthalmology Real Estate Investors, LLC
    
    FLOrlando Opthalmology Surgery Center, LLC
    
    FLOrtho Excel, Inc.
    
    DEOrthoLink ASC Corporation
    
    TN




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OrthoLink Baptist ASC, LLC
    
    TNOrthoLink Physicians Corporation
    
    DEOrthoLink Radiology Services Corporation
    
    TNOrthoLink/ Georgia ASC, Inc.
    
    GAOrthoLInk/New Mexico ASC, Inc.
    
    GAOrthoLink/TN ASC, Inc.
    
    TNOrthopedic and Surgical Specialty Company, LLC (doing business as Arizona Orthpedic Surgical Hospital)
    
    AZOrthopedic South Surgical Partners, LLC (doing business as Orthopedic South Surgical Center)
    
    GAPacific Endo-Surgical Center, L.P.
    
    CAPark Cities Surgery Center, L.P.
    
    TXPark Cities/Trophy Club GP, LLC
    
    TXParkway Surgery Center, LLC
    
    NVParkwest Surgery Center, L.P.
    
    TNPasadena Holdings, LLC
    
    NVPearland Ambulatory Surgery Center, Ltd.
    
    TNPendragon Development, LLC
    
    ILPhysicians Data Professionals, Inc.
    
    TXPhysicians Pavilion, L.P. (doing business as Physicians Pavilion Surgery Center)
    
    DEPhysicians Surgery Center of Knoxville, LLC
    
    TNPhysicians Surgical Center of Ft. Worth, LLP (doing business as (1) Physicians Surgical Center of Ft. Worth
and (2)
   Physicians Surgical Center of Ft. Worth II)
    
    TXProvidence/USP Santa Clarita GP, LLC
    
    CAProvidence/USP Surgery Centers, L.L.C.
    
    CARadsource, LLC
    
    DEReading Ambulatory Surgery Center, L.P. (doing business as Reading Surgery Center)
    
    PARedmond Surgery Center, LLC
    
    TNResurgens Surgery Center, LLC
    
    GARichmond ASC Leasing Company, LLC
    
    VARiver North Same Day Surgery, L.L.C.
    
    ILRiverside Ambulatory Surgery Center, L.P.
    
    MORockwall Ambulatory Surgery Center, L.L.P. (doing business as Rockwall Surgery Center)
    
    TXRockwall/Heath Surgery Center, L.L.P. (doing business as Baylor Surgicare at Heath)
    
    TXRoseville Surgery Center, L.P.
    
    CARoswell Surgery Center, L.L.C.
    
    GASaint Thomas Campus Surgicare, L.P. (doing business as Saint Thomas Surgicare)
    
    TNSaint Thomas/USP  Baptist Plaza, L.L.C.
    
    TNSaint Thomas/USP Surgery Centers, L.L.C.
    
    TNSaint Thomas/USP Surgery Centers II, LLC
    
    TNSame Day Surgery, LLC
    
    ILSame Day Management, L.L.C.
    
    ILSan Antonio Endoscopy, L.P. (doing business as San Antonio Endoscopy Center)
    
    TXSan Fernando Valley Surgery Center, L.P. (doing business as Providence Holy Cross Surgery Center at Mission Hills)
    
    CASan Gabriel Ambulatory Surgery Center, L.P.
    
    CASan Gabriel Valley Surgical Center, L.P.
    
    CASan Martin Surgery Center, LLC (doing business as Durango Outpatient Surgery Center)
    
    NVSand Lake Surgery Center, L.P.
    
    DESanta Clarita Surgery Center, L.P.
    
    CAScripps Encinitas Surgery Center, LLC
    
    CAScripps/USP Surgery Centers, L.L.C.
    
    CAShrewsbury Surgery Center, LLC
    
    NJShore Outpatient Surgicenter, L.L.C.
    
    GAShoreline Real Estate Partnership, LLP
    
    TXShoreline Surgery Center, LLP (doing business as CHRISTUS Spohn  Surgicare of Corpus Christi)
    
    TXSouthwest Ambulatory Surgery Center, L.L.C. (doing business as Southwest Orthopedic Ambulatory Surgery Center)
    
    OKSpecialists Surgery Center, L.L.C.
    
    OKSpecialty Surgicenters, Inc.
    
    GASSI Holdings, Inc.
    
    GASSM St. Clare Surgical Center, L.L.C.
    
    MOSt. Agnes/USP Joint Venture, LLC
    
    MDSt. Johns Outpatient Surgery Center, LP
    
    CASt. Josephs Outpatient Surgery Center, LLC
    
    AZSt. Marys Ambulatory Surgery Center, LLC
    
    VASt. Marys Surgical Center, LLC
    
    MOSt. Marys/USP Surgery Centers, LLC
    
    MOSt. Vincent Health/USP, LLC
    
    INSugar Land Surgical Hospital, LLP
    
    TXSummit Radiology, LLC
    
    ILSunset Hills Ambulatory Surgery Center, L.P. (doing business as Sunset Hills Surgery Center)
    
    MOSuburban Endoscopy Services, LLC
    
    TNSurgery Center of Canfield, LLC
    
    OHSurgery Center of Columbia, L.P.
    
    MOSurgery Center of Gilbert, LLC
    
    AZSurgery Center of Peoria, LLC
    
    AZSurgery Center of Scottsdale, LLC
    
    AZSurgery Center of Tempe, LLC (doing business as Physicians Surgery Center of Tempe)
    
    OKSurgery Centers Holdings Company, L.L.C.
    
    OKSurgery Centers of America II, LLC
    
    OKSurgicoe of Texas, Inc.
    
    TXSurginet, Inc.
    
    TNSurginet of Rivergate, Inc.
    
    TNSurgis, Inc.
    
    DESurgis Management Services, Inc.
    
    TNSurgis of Chico, Inc.
    
    CASurgis of Pearland, Inc.
    
    TN




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Surgis of Phoenix, Inc.
    
    TNSurgis of Redding, Inc.
    
    TNSurgis of Rivergate, Inc.
    
    TNSurgis of Sand Lake, Inc.
    
    TNSurgis of Sonama, Inc.
    
    TNSurgis of Victoria, Inc.
    
    TNSurgis of Willowbrook, Inc.
    
    TNTamarac Surgery Center LLC (doing business as Surgery Center of Ft. Lauderdale)
    
    FLTempleton Surgery Center, LLC
    
    TNTerre Haute Surgical Center, LLC (doing business as St. Vincent Surgery Center of Terre Haute)
    
    INTeton Outpatient Services, LLC
    
    WYTexan Ambulatory Surgery Center, L.P. (doing business as Texan Surgery Center)
    
    TXTexas Health Venture Arlington L.P.
    
    TXTexas Health Venture Arlington Hospital, LLC
    
    TXTexas Health Venture Bellaire, L.P.
    
    TXTexas Health Venture Denton L.P.
    
    TXTexas Health Venture DSP L.P.
    
    TXTexas Health Venture Fort Worth, L.L.C.
    
    TXTexas Health Venture Frisco, L.P.
    
    TXTexas Health Venture Garland, L.P.
    
    TXTexas Health Venture Grapevine L.P.
    
    TXTexas Health Venture Huguley, L.P.
    
    TXTexas Health Venture Irving-Coppell, L.P.
    
    TXTexas Health Venture North Garland, L.P.
    
    TXTexas Health Venture Park Cities, L.P.
    
    TXTexas Health Venture Park Cities/Trophy Club, LP
    
    TXTexas Health Venture Plano, LLC
    
    TXTexas Health Venture Rockwall, L.P.
    
    TXTexas Health Venture Rockwall 2, L.P.
    
    TXTexas Health Ventures Group L.L.C.
    
    TXTexas Health Ventures Group Holdings, LLC
    
    NVThe Ambulatory Surgical Center of St. Louis, L.P.
    
    MOThe Center for Ambulatory Surgical Treatment, L.P.
    
    CAThe Surgery Center, an Ohio limited partnership
    
    OHThe Surgery Center at Tri-City Orthopaedic Clinic, LLC
    
    WAThe Surgery Center Pearl, L.L.C.
    
    OHTHVG Arlington GP, LLC
    
    DETHVG Bedford GP, LLC
    
    DETHVG Bedford, L.P.
    
    TXTHVG Bellaire GP, LLC
    
    TXTHVG Denton GP, LLC
    
    DETHVG DeSoto GP, LLC
    
    DETHVG DeSoto, L.P.
    
    TXTHVG DSP GP, LLC
    
    DETHVG Fort Worth GP, LLC
    
    DETHVG Fort Worth, L.P.
    
    TXTHVG Frisco GP, LLC
    
    DETHVG Garland GP, LLC
    
    DETHVG Grapevine GP, LLC
    
    DETHVG Huguley GP, LLC
    
    DETHVG Irving-Coppell GP, LLC
    
    DETHVG Lewisville GP, LLC
    
    DETHVG Lewisville, L.P.
    
    TXTHVG North Garland GP, LLC
    
    DETHVG Park Cities GP, LLC
    
    TXTHVG Park Cities/Trophy Club GP, LLC
    
    TXTHVG Rockwall GP, LLC
    
    DETHVG Rockwall 2 GP, LLC
    
    TXTHVG Valley View GP, LLC
    
    DETHVG Valley View L.P.
    
    TXTHVG/HeatlhFirst, LLC
    
    TXTHVG/HealthFirst Holdings, LLC
    
    NVTMC Holding Company, LLC
    
    TXToms River Surgery Center, L.L.C.
    
    NJTOPS Specialty Hospital, Ltd.
    
    TXTrophy Club Medical Center, L.P. (dba Baylor Medical Center at Trophy Club)
    
    TXTulsa Outpatient Surgery Center, LLC
    
    OKUnited Surgery Center  Southeast, Ltd.
    
    TXUniversity Surgical Partners of Dallas, L.L.P.
    
    TXUnited Surgical of Atlanta, Inc.
    
    GAUnited Surgical Partners Holdings, Inc.
    
    DEUniversity Surgery Center, Ltd.
    
    FLUSP Alexandria, Inc.
    
    LAUSP Assurance Company
    
    VTUSP Austin, Inc.
    
    TXUSP Austintown, Inc.
    
    OHUSP Baton Rouge, Inc.
    
    LAUSP Baltimore, Inc.
    
    MDUSP Bridgeton, Inc.
    
    MOUSP Cedar Park, Inc.
    
    TXUSP Central New Jersey, Inc.
    
    NJUSP Chesterfield, Inc.
    
    MOUSP Chicago, Inc.
    
    ILUSP Cleveland, Inc.
    
    OH




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USP Coast, Inc.
    
    CAUSP Columbia, Inc.
    
    MOUSP Corpus Christi, Inc.
    
    TXUSP Cottonwood, Inc.
    
    AZUSP Creve Coeur, Inc.
    
    MOUSP Decatur, Inc.
    
    TNUSP Des Peres, Inc.
    
    MOUSP Destin, Inc.
    
    FLUSP Domestic Holdings, Inc.
    
    DEUSP Fenton, Inc.
    
    MOUSP Florissant, Inc.
    
    MOUSP Fredericksburg, Inc.
    
    VAUSP Frontenac, Inc.
    
    MOUSP Glendale, Inc.
    
    CAUSP Harbour View, Inc.
    
    VAUSP Houston, Inc.
    
    TXUSP Indiana, Inc.
    
    INUSP International Holdings, Inc.
    
    DEUSP Kansas City, Inc.
    
    MOUSP Knoxville, Inc.
    
    TNUSP Las Cruses, Inc.
    
    NMUSP Long Island, Inc.
    
    DEUSP Lyndhurst, Inc.
    
    OHUSP Mason Ridge, Inc.
    
    MOUSP Michigan, Inc.
    
    MIUSP Midwest, Inc.
    
    ILUSP Mission Hills, Inc.
    
    CAUSP Nevada, Inc.
    
    NVUSP Nevada Holdings, LLC
    
    NVUSP Newport News, Inc.
    
    VAUSP New Jersey, Inc.
    
    NJUSP North Kansas City, Inc.
    
    MOUSP North Texas, Inc.
    
    DEUSP Oklahoma, Inc.
    
    OKUSP Olive, Inc.
    
    MOUSP Oxnard, Inc.
    
    CAUSP Phoenix, Inc.
    
    AZUSP Portland, Inc.
    
    ORUSP Reading, Inc.
    
    PAUSP Richmond, Inc.
    
    VAUSP Richmond II, Inc.
    
    VAUSP Sacramento, Inc.
    
    CAUSP San Antonio, Inc.
    
    TXUSP San Gabriel, Inc.
    
    CAUSP Sarasota, Inc.
    
    FLUSP Securities Corporation
    
    TNUSP St. Peters, Inc.
    
    MOUSP Sunset Hills, Inc.
    
    MOUSP Tennessee, Inc.
    
    TNUSP Texas, L.P.
    
    TXUSP Texas Air, L.L.C.
    
    TXUSP Torrance, Inc.
    
    CAUSP Turnersville, Inc.
    
    NJUSP Virginia Beach, Inc.
    
    VAUSP Webster Groves, Inc.
    
    MOUSP West Covina, Inc.
    
    CAUSP Westwood, Inc.
    
    CAUSP Winter Park, Inc.
    
    FLUSPE Holdings Limited
    
    UKUSPI San Diego, Inc.
    
    CAUtica ASC Partners, LLC (doing business as Utica Surgery Cetner)
    
    MIValley View Surgicare Partners, Ltd. (doing business as Baylor Surgicare at Valley View)
    
    TXVeroscan, Inc.
    
    DEVictoria Ambulatory Surgery Center, LP (doing business as The Surgery Center)
    
    DEWarner Park Surgery Center, LP
    
    AZWebster Ambulatory Surgery Center, L.P. (doing business as Webster Surgery Center)
    
    MOWest Houston Ambulatory Surgical Associates, L.P.
    
    TXWHASA, LC
    
    TXWillowbrook Ambulatory Surgery Center, L.P.
    
    TN