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                                                                  Exhibit 4.3(d)

                                FOURTH AMENDMENT
                               TO CREDIT AGREEMENT


         FOURTH AMENDMENT TO CREDIT AGREEMENT, dated as of August 20, 1998 (this
"Amendment"), among UNIVERSAL HOSPITAL SERVICES, INC., a Minnesota corporation
(the "Borrower"), the financial institutions party to the Credit Agreement
described below (the "Banks") and BANKERS TRUST COMPANY, as Administrative
Agent. All capitalized terms used herein and not otherwise defined shall have
the respective meanings provided such terms in the Credit Agreement referred to
below.

                              W I T N E S S E T H :

         WHEREAS, the Borrower, the Banks and the Administrative Agent are
parties to a Credit Agreement, dated as of February 25, 1998 (as amended,
modified and supplemented through, but not including, the date hereof, the
"Credit Agreement");

         WHEREAS, Fleet National Bank desires to become a party to the Credit
Agreement as a Bank;

         WHEREAS, the parties hereto wish to amend the Credit Agreement as
herein provided; and

         NOW THEREFORE, it is agreed:

         1.       Section 10 of the Credit Agreement is hereby amended by:

                  (i) deleting the proviso appearing in the definition of
         "Revolving Commitment."

                  (ii) (x) deleting the text "either or both of" appearing in
         the definition of "Over-Advance Commitment" and (y) deleting the text
         "or the proviso to the definition of 'Revolving Commitment'" appearing
         in the definition of "Over-Advance Commitment."

                  (iii) (x) deleting the text "either" appearing immediately
         before the text "the final proviso" in the definition of "Over-Advance
         Loans", (y) deleting the text "or the proviso to the definition of
         'Revolving Commitment'" appearing in said definition and (z) deleting
         the text "either of such provisos" appearing in the parenthetical in
         said definition and inserting the text "such proviso" in lieu thereof.

                  (iv) deleting the amount "$48,000,000" appearing in the
         proviso in the definition of "Borrowing Base" and inserting the amount
         "$50,000,000" in lieu thereof.

         2. Schedule I to the Credit Agreement is hereby amended by deleting
said Schedule I in its entirety and inserting in lieu thereof Schedule I hereto.


              
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         3. By its signature hereto, Fleet National Bank hereby (i) confirms
that it has received a copy of the Credit Agreement and the other Credit
Documents, together with copies of the financial statements referred to therein
and such other documents and information as it has deemed appropriate to make
its own credit analysis and decision to become a party to the Credit Agreement;
(ii) agrees that it will, independently and without reliance upon the
Administrative Agent or any other Bank and based on such documents and
information as it shall deem appropriate at the time, continue to make its own
credit decisions in taking or not taking action under the Credit Agreement;
(iii) appoints and authorizes the Administrative Agent to take such action as
agent on its behalf and to exercise such powers under the Credit Agreement and
the other Credit Documents as are delegated to the Administrative Agent by the
terms thereof, together with such powers as are reasonably incidental thereto;
and (iv) agrees that it will perform in accordance with their terms all of the
obligations which by the terms of the Credit Agreement and the Other Credit
Documents are required to be performed by it as a Bank.

         4. Fleet shall have received a Revolving Note signed by the Borrower
and in the amount of its Revolving Commitment and otherwise in conformity with
the provisions of Section 1.05 of the Credit Agreement.

         5. Any lending institution which becomes a party to the Credit
Agreement as a Bank after the Third Amendment Effective Date and prior to the
Over-Advance Maturity Date shall assume its pro rata portion of the Over-Advance
Commitment.

         6. This Amendment is limited precisely as written and shall not be
deemed to be a consent to or modification of any other term or condition of the
Credit Agreement, the other Credit Documents or any of the instruments or
agreements referred to therein.

         7. In order to induce the Banks to enter into this Amendment, the
Borrower hereby represents and warrants that (x) no Default or Event of Default
exists on the Fourth Amendment Effective Date (as defined below) both before and
after giving effect to this Amendment and (y) all of the representations and
warranties contained in the Credit Documents shall be true and correct in all
material respects on the Fourth Amendment Effective Date both before and after
giving effect to this Amendment with the same effect as though such
representations and warranties had been made on and as of the Fourth Amendment
Effective Date (it being understood that any representation or warranty made as
of a specific date shall be true and correct in all material respects as of such
specific date).

         8. This Amendment shall become effective (simultaneously with the
satisfaction of the last of the conditions described below) on the first date
that (such effective date being herein referred to as the "Fourth Amendment
Effective Date") the Borrower, each of the Banks and Fleet National Bank shall
have signed a counterpart hereof (whether the same or different counterparts)
and shall have delivered (including by way of telecopier) the same to the
Administrative Agent at its Notice Office.


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         9. This Amendment may be executed in any number of counterparts and by
the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A complete set of
counterparts shall be lodged with the Borrower and the Administrative Agent.

         10. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE
STATE OF NEW YORK.

         11. From and after the Fourth Amendment Effective Date, all references
in the Credit Agreement and each of the Credit Documents to the Credit Agreement
shall be deemed to be references to such Credit Agreement as amended hereby.

                   [Signatures appear on the following pages]



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         IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart
of this Amendment to be duly executed and delivered as of the date first above
written.

                                    UNIVERSAL HOSPITAL SERVICES, INC.


                                    By: _____________________________
                                    Title: ___________________________


                                    BANKERS TRUST COMPANY,
                                    Individually as Administrative Agent


                                    By: _____________________________
                                    Title: ___________________________


                                    HELLER FINANCIAL, INC.


                                    By: _____________________________
                                    Title: ___________________________


                                    FLEET NATIONAL BANK


                                    By: _____________________________
                                    Title: ___________________________



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                                                                      SCHEDULE I

                                   COMMITMENTS



        Bank                                      Revolving Commitment
        ----                                      --------------------
Bankers Trust Company                                 $20,000,000
Heller Financial, Inc.                                $20,000,000
Fleet National Bank                                   $10,000,000
                                                      -----------
Total:                                                $50,000,000



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