<PAGE>   1
                                                                   EXHIBIT 10.14

                                 FIRST AMENDMENT

         FIRST AMENDMENT, dated as of August 22, 2001 (this "Amendment"), to
the Credit Agreement, dated as of October 25, 1999 (as amended, supplemented or
otherwise modified prior to the date hereof, the "Credit Agreement"), among
UNIVERSAL HOSPITAL SERVICES, INC., a Minnesota corporation (the "Borrower"), the
several lenders from time to time parties thereto (the "Lenders"), KEY CORPORATE
CAPITAL INC., as collateral agent, HELLER FINANCIAL INC., as syndication agent,
CANADIAN IMPERIAL BANK OF COMMERCE, as administrative agent for the Lenders (in
such capacity, the "Administrative Agent"), and CIBC WORLD MARKETS CORP., as
lead arranger and book manager thereunder. Capitalized terms not otherwise
defined herein shall have the same meanings as specified therefor in the Credit
Agreement.

                                    RECITALS

         The Borrower has requested that the Administrative Agent and the
Lenders agree to amend the Credit Agreement as set forth in this Amendment, and
the Administrative Agent and the Lenders are willing to agree to such
amendments, but only on the terms and subject to the conditions set forth in
this Amendment.

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the Borrower, the Administrative Agent and the Lenders hereby
agree as follows:

              1.       Amendments to Credit Agreement. The Credit Agreement is
hereby amended as follows:

              (a) Upon the satisfaction of the condition set forth in Section
         3(b) of this Amendment, Section 1.1 of the Credit Agreement shall be
         amended by adding the following definition after the definition of
         "Person":

                        ""PIK Preferred Stock":  as defined in Section 9.7(e)."

              (b) Upon the satisfaction of the condition set forth in Section
         3(b) of this Amendment, Section 1.1 of the Credit Agreement shall be
         amended by adding the following definition after the definition of
         "Indebtedness":

                        ""Initial Public Offering": the Public Offering to be
              consummated no later than December 31, 2001 and which  yields Net
              Proceeds to the Borrower in an amount not less than $60,000,000."

              (c) The definition of "Specified Capital Expenditures" in Section
         1.1 of the Credit Agreement is hereby amended by deleting such
         definition in its entirety and substituting in lieu thereof a new
         definition to read as follows:

                        ""Specified Capital Expenditures": (a) for any fiscal
              quarter of the Borrower ended on or prior to December 31, 2001,
              50% of the aggregate amount of Capital Expenditures made by the
              Borrower and its Subsidiaries during such fiscal quarter, and (b)
              for each fiscal quarter of the Borrower ended during any period
              set forth in the table below, the percentage set forth opposite
              such period in the table below of the aggregate amount of Capital
              Expenditures made by the Borrower and its Subsidiaries during such
              fiscal quarter:

<TABLE>
<CAPTION>
              ------------------------------------------------------------------
                              Period                                  Percentage
              ------------------------------------------------------------------
<S>                                                                   <C>
              January 1, 2002 through December 31, 2002                 40%
              ------------------------------------------------------------------
              January 1, 2003 through December 31, 2003                 30%
              ------------------------------------------------------------------
</TABLE>


<PAGE>   2

<TABLE>
<CAPTION>
              ------------------------------------------------------------------
                              Period                                  Percentage
              ------------------------------------------------------------------
<S>                                                                   <C>
              January 1, 2004 and thereafter                            20%
              ------------------------------------------------------------------
</TABLE>

              (d) Upon the satisfaction of the condition set forth in Section
         3(b) of this Amendment, Section 1.1 of the Credit Agreement shall be
         amended by adding the following definition after the definition of
         "Collateral Agent":

                        ""Common Stock Warrant": the warrant to purchase up to
              350,000 shares of common stock, par value $0.01 per share, of the
              Borrower, issued pursuant to the Warrant Purchase Agreement, dated
              as of December 18, 1998."

              (e) Upon the satisfaction of the condition set forth in Section
         3(b) of this Amendment, Section 5.5(c) of the Credit Agreement shall be
         amended by adding immediately after the phrase "Permitted Acquisition,"
         in subsection (i) the following:

           "provided that in connection with the Initial Public Offering, the
              Borrower shall prepay the Revolving Credit Loans in an amount
              equal to 75% of the Net Proceeds of the Initial Public Offering,
              and shall reduce the Revolving Credit Commitments in an amount
              equal to 50% of the Net Proceeds of the Initial Public Offering,"

              (f) Section 9.5 of the Credit Agreement is hereby amended by (i)
         deleting the "and" at the end of subsection (a), (ii) deleting the
         period at the end of subsection (b) and substituting in lieu thereof";
         and", and (iii) adding a new subsection 9.5(c) to read as follows:

                        "(c) the Borrower may merge with and into a newly formed
              corporation incorporated in Delaware having the identical
              stockholders and having identical numbers of and classes of stock
              as the Borrower, solely for the purpose of the Borrower becoming
              incorporated in Delaware, the terms of which transaction and all
              legal matters in respect thereof shall be reasonably satisfactory
              to the Administrative Agent."

              (g) Section 9.16 of the Credit Agreement is hereby amended by
         adding at the end of such Section immediately after the phrase
         "withheld or delayed", the following new proviso:

           "provided, however, that (a) in connection with the Borrower's
              reincorporation described in Section 9.5(c), the Borrower may
              adopt the Certificate of Incorporation and Bylaws previously
              provided to the Administrative Agent, and (b) in connection with
              the reverse stock split to be adopted prior to the Initial Public
              Offering, the Borrower may amend its Articles of Incorporation to
              reflect such reverse stock split so long as the percentage of
              authorized shares of any class or series of Capital Stock that
              remains unissued after such amendment shall be the same as the
              percentage of authorized shares of that class or series that were
              unissued before the amendment."

              (h) Upon the satisfaction of the condition set forth in Section
         3(b) of this Amendment, Section 9.7 of the Credit Agreement shall be
         amended by (i) deleting the "and" at the end of subsection (c), (ii)
         deleting the period at the end of subsection (b) and substituting in
         lieu thereof "; and", and (iii) adding a new subsection 9.7(e) to read
         as follows:

                        "(e) so long as no Event of Default has occurred and is
              continuing or would result therefrom, the Borrower may redeem (i)
              all but not less than all of the shares of its Series B 13%
              Cumulative Accruing Pay-In-Kind Preferred Stock (the "PIK
              Preferred Stock"), including accrued dividends, upon the terms and
              conditions set forth in the Certificate of Designations of the PIK
              Preferred Stock for a redemption pursuant to Section 5(b)(ii) of
              such Certificate of Designations and at the "Offering Redemption
              Price", as defined in such Certificate of Designations, and (ii)
              the Common Stock Warrant at a redemption price per share of common
              stock subject to the Common Stock



                                       2
<PAGE>   3


              Warrant not to be greater than the excess of the offering price
              per share for the common stock offered in the Initial Public
              Offering over the exercise price per share set forth in the Common
              Stock Warrant, in each case solely from the Net Proceeds of the
              Initial Public Offering, provided that (A) such redemptions shall
              be completed within 15 days following the Initial Public Offering
              and (B) the portion of the aggregate Net Proceeds of the Initial
              Public Offering so applied to redeem the PIK Preferred Stock and
              the Common Stock Warrant shall not exceed 25% of the aggregate
              amount of the Net Proceeds of the Initial Public Offering."

              (i) The table set forth in Section 9.8 of the Credit Agreement is
         hereby amended by (i) deleting the amount "$42,500,000" listed under
         the heading "Amount" opposite the phrase "Fiscal year ending December
         31, 2003" and substituting in lieu thereof the amount "$50,000,000",
         and (ii) deleting the amount "$42,500,000" listed under the heading
         "Amount" opposite the phrase "January 1, 2004 through the Revolving
         Credit Termination Date" and substituting in lieu thereof the amount
         "$57,000,000".

              2.        Representations and Warranties. To induce the
Administrative Agent and the Lenders to enter into this Amendment, the Borrower
hereby represents and warrants that after giving effect to the amendments
provided for herein, the representations and warranties contained in the Credit
Agreement and the other Loan Documents will be true and correct in all material
respects as if made on and as of the date hereof and no Default or Event of
Default will have occurred and be continuing.

              3.       Effectiveness.

              (a) The effectiveness of this Amendment is subject to the
         satisfaction of the following conditions precedent (the date of such
         satisfaction, the "Effective Date"):

                        (i)   the receipt by the Administrative Agent of this
              Amendment duly executed and delivered by duly authorized officers
              of the Borrower, the Administrative Agent and the Lenders having
              Credit Exposure Percentages aggregating at least 66 2/3%;

                        (ii)  the Borrower shall have paid to the Administrative
              Agent, for the account of the Lenders which have executed and
              delivered this Amendment prior to August 27, 2001, an amendment
              fee in the amount set forth in the letter from the Administrative
              Agent and the Arranger dated August 20, 2001;

                        (iii) the receipt by the Administrative Agent of any
              other documents relating hereto that the Administrative Agent
              shall reasonably request prior to the date hereof; and

                        (iv)  after giving effect to the amendments provided for
              herein, the representations and warranties contained in the Credit
              Agreement and in the other Loan Documents will be true and correct
              in all material respects as if made on and as of the Effective
              Date and no Default or Event of Default will have occurred and be
              continuing.

              (b) The amendments to the Credit Agreement set forth in Sections
         1(a), (b), (d), (e) and (h) of this Amendment shall be effective only
         upon the satisfaction of the following conditions precedent:

                        (i)   the consummation of the Initial Public Offering on
              or prior to December 31, 2001;

                        (ii)  the receipt by the Borrower of Net Proceeds of at
              least $60,000,000 from the Initial Public Offering;



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<PAGE>   4

                        (iii) the receipt by the Administrative Agent of copies
              of the registration statement (including the prospectus contained
              therein, and any amendments thereto), and any other documents
              relating to the Initial Public Offering reasonably requested by
              the Administrative Agent; and

                        (iv)  immediately prior to, and after giving effect to,
              the Initial Public Offering and the amendments to the Credit
              Agreement contemplated by Sections 1(a), (b), (d), (e) and (h) of
              this Amendment, (x) all of the representations and warranties
              contained in the Credit Agreement and in the other Loan Documents
              (as so amended) will be true and correct in all material respects
              as if made on and as of the effective date of the Initial Public
              Offering, and (y) no Default or Event of Default will have
              occurred and be continuing.

              4. No Other Amendments. Except as expressly amended hereby, the
Credit Agreement and the other Loan Documents shall remain in full force and
effect in accordance with their respective terms, without any waiver, amendment
or modification of any provision thereof.

              5. Counterparts. This Amendment may be executed by one or more of
the parties hereto on any number of separate counterparts and all of such
counterparts taken together shall be deemed to constitute one and the same
instrument.

              6. Expenses. The Borrower agrees to pay and reimburse the
Administrative Agent for all of the reasonable out-of-pocket costs and expenses
incurred by the Administrative Agent in connection with the preparation,
execution and delivery of this Amendment, including, without limitation, the
reasonable fees and disbursements of Cadwalader, Wickersham & Taft, counsel to
the Administrative Agent.

              7. No Defenses, Release. None of the Borrower nor any other Loan
Party has any claims, counterclaims, offsets or defenses to the Loan Documents
or the Obligations, or if any such Person does have any claims, counterclaims,
offsets or defenses to the Loan Documents or the Obligations, the same are
hereby waived, relinquished and released in consideration of the execution and
delivery of this Amendment by the Lenders parties hereto. By its execution
hereof and in consideration of the mutual covenants contained herein and the
accommodations granted to the Borrower hereunder, the Borrower on behalf of
itself and the other Loan Parties expressly waives and releases any and all
claims and causes of actions any of them may have, or allege to have (and all
defenses which may arise out of any of the foregoing), whether known or unknown,
against the Administrative Agent or any Lender or any of their Affiliates,
employees, directors, officers, attorneys or agents, arising out of the credit
relationship between the Borrower and the Lenders up to and including the date
of this Amendment.

              8. Integration. This Amendment, the Credit Agreement and the other
Loan Documents represent the agreement of the Borrower, the Administrative Agent
and the Lenders with respect to the subject matter hereof, and there are no
promises, undertakings, representations or warranties by the Administrative
Agent or any Lender relative to the subject matter hereof not expressly set
forth or referred to herein or in Credit Agreement or the other Loan Documents.

              9. APPLICABLE LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

                            [SIGNATURE PAGES FOLLOW]


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<PAGE>   5




              IN WITNESS WHEREOF, the parties hereto have caused this Amendment
to be executed and delivered by their proper and duly authorized officers as of
the day and year first above written.


                                    UNIVERSAL HOSPITAL SERVICES, INC.




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:


                                    CANADIAN IMPERIAL BANK OF COMMERCE, AS
                                        ADMINISTRATIVE AGENT




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:


                                    KEY CORPORATE CAPITAL INC., AS COLLATERAL
                                        AGENT AND AS A LENDER




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:


                                    CIBC INC.




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:


                                    FLEET NATIONAL BANK




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:



<PAGE>   6


                                    HELLER FINANCIAL, INC., AS SYNDICATION AGENT




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:


                                    NATIONAL BANK OF CANADA




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title:


                                    TRANSAMERICA BUSINESS CREDIT
                                        CORPORATION




                                    By:
                                        ----------------------------------------
                                        Name:
                                        Title: