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                                                                  Exhibit 4.3(b)

                                SECOND AMENDMENT
                               TO CREDIT AGREEMENT



         SECOND AMENDMENT TO CREDIT AGREEMENT, dated as of July 30, 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, the parties hereto wish to amend the Credit Agreement as
herein provided; and

         NOW THEREFORE, it is agreed:

         1. Section 7.01(k) of the Credit Agreement is hereby amended by (i)
deleting the text "commercially reasonable judgment" appearing therein and
inserting the text "sole and absolute discretion" in lieu thereof and (ii)
inserting the text "and/or on a physical inspection basis (such basis to be
determined by the Administrative Agent in its sole and absolute discretion)"
immediately after the text "an update (an "Appraisal Update") on a desk top
basis" appearing therein.

         2. Section 8.02 of the Credit Agreement is hereby amended by (a)
deleting the text "and" appearing at the end of clause (j) thereof, (b) deleting
the period appearing at the end of clause (k) thereof and inserting the text ";
and" in lieu thereof and (c) inserting the following new clause (l) immediately
after clause (k) thereof:

         "(l) the Borrower may consummate the HCI Acquisition."

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

                   (i) deleting the text "50%" appearing in the definition of
         "Borrowing Base" and inserting the text "60%" in lieu thereof;

                  (ii) deleting the text "180 days" appearing in the definition
         of "Eligible Receivables" and inserting the text "90 days" in lieu
         thereof; and


                           
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                  (iii) inserting the following new definitions in the
         appropriate alphabetical order: " 'HCI' shall mean HCI Acquisition
         Corp., a Missouri corporation."

                           " 'HCI Acquisition' shall mean the acquisition by the
                  Borrower of all of the issued and outstanding shares of
                  capital stock of HCI pursuant to and in accordance with the
                  HCI Acquisition Documents."

                           " 'HCI Acquisition Agreement' shall mean the Stock
                  Purchase and Sale Agreement, dated as of July 30, 1998, by and
                  among the Borrower and the selling shareholders of HCI party
                  thereto."

                           " 'HCI Acquisition Documents' shall mean the HCI
                  Acquisition Agreement and all other documents required to be
                  entered into or delivered pursuant to the terms and conditions
                  of the HCI Acquisition Agreement."

         4. Schedule I to the Credit Agreement is hereby amended by deleting
said Schedule in its entirety and inserting Schedule I to this Amendment in lieu
thereof as new Schedule I to the Credit Agreement. The parties to this Amendment
agree that (i) promptly after the Second Amendment Effective Date the Borrower
shall deliver to each Bank a Revolving Note in the form of Exhibit B-1 to the
Credit Agreement which Revolving Notes shall reflect the changes to Schedule I
which are made pursuant to this paragraph 4 and (ii) each Bank receiving a new
Revolving Note pursuant to clause (i) above shall promptly thereafter deliver to
the Borrower any Revolving Notes previously issued to such Bank.

         5. 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.

         6. 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 Second 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 Second 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 Second 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).

         7. 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 "Second Amendment
Effective Date"):


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                  (i) the Borrower and the Required Banks (which shall in any
         event include any Bank whose Revolving Commitment is increased pursuant
         to paragraph 4 of this Amendment) 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;

                  (ii) true and correct copies of the HCI Acquisition Documents
         shall have been delivered to the Administrative Agent, and all terms of
         the HCI Acquisition Documents shall be satisfactory in form and
         substance to the Administrative Agent;

                  (iii) the HCI Acquisition Documents (and the transactions
         contemplated thereby) shall have been duly approved by the boards of
         directors and, if required by appli-cable law, the stockholders of the
         parties thereto, and all HCI Acquisition Documents shall have been duly
         executed and delivered by the parties thereto and shall be in full
         force and effect;

                  (iv) each of the conditions precedent to the obligation of the
         parties to consummate the HCI Acquisition as set forth in the HCI
         Acquisition Agreement shall have been satisfied to the satisfaction of
         the Administrative Agent and the Required Banks, or waived with the
         consent of the Administrative Agent and the Required Banks, and the HCI
         Acquisition shall have been consummated in accordance with the HCI
         Acquisition Documents (without giving effect to any material amendment
         or modification of the HCI Acquisition Agreement or waiver with respect
         thereto unless consented to by the Administrative Agent and the
         Required Banks) and all applicable laws, rules and regulations;

                  (v) the Borrower shall have delivered the following to the
         Administrative Agent:

                           (a) certified copies of Requests for Information or
                  Copies (Form UCC-11), or equivalent r eports, each of recent
                  date listing all effective financing statements that name HCI
                  and/or any of its subsidiaries and are filed in either (x) any
                  jurisdiction in which HCI or any subsidiary of HCI maintains
                  its chief executive office or (y) any other jurisdiction in
                  which any assets of HCI or any subsidiary of HCI are located,
                  together with (1) copies of any Financing Statements that name
                  HCI or any subsidiary of HCI as debtor and (2) evidence of
                  filing of appropriate termination statements executed by the
                  secured lender in respect of any Financing Statements referred
                  to in clause (1) above;

                           (b) executed Financing Statements (Form UCC-1) in
                  appropriate form for filing under the UCC of each jurisdiction
                  referred to in clause (a) above as may be necessary to perfect
                  the security interests purported to be created by the Security
                  Agreement in the assets of HCI and its subsidiaries;


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                           (c) evidence of the completion of (or evidence of the
                  making of arrangements satisfactory to the Administrative
                  Agent for the completion of) all other recordings and filings
                  of, or with respect to, HCI and its subsidiaries and/or their
                  assets as may be necessary or, in the reasonable opinion of
                  the Collateral Agent, desirable to perfect the security
                  interests intended to be created by the Security Agreement in
                  the assets of HCI and its subsidiaries (including, without
                  limitation, filings and registrations with respect to
                  copyrights, patents and trademarks); and

                           (d) evidence that all other actions necessary or, in
                  the reasonable opinion of the Collateral Agent, desirable to
                  perfect and protect the security interests purported to be
                  created by the Security Agreement in the assets of HCI and its
                  subsidiaries have been taken;

                  (vi) HCI and each of its subsidiaries shall have executed and
         delivered to the Administrative Agent a subsidiary assumption agreement
         in form and substance satisfactory to the Administrative Agent;

                  (vii) the Borrower and each of its subsidiaries shall have
         delivered to the Collateral Agent all stock certificates and notes
         (duly endorsed in blank) which represent Securities (as defined in the
         Pledge Agreement) which are owned (after giving effect to the HCI
         Acquisition) by the Borrower and/or any of its subsidiaries, together
         with executed and undated stock powers, in the case of Stock (as
         defined in the Pledge Agreement);

                  (viii) the Borrower shall have delivered a certificate of an
         Authorized Officer, dated the Second Amendment Effective Date, stating
         that all of the conditions set forth in clauses (iii) and (iv) above
         have been satisfied as of such date; and

                  (ix) HCI and each of its subsidiaries shall have executed and
         delivered the subsidiary guaranty, in the form of Exhibit G to the
         Credit Agreement.

         8. 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.

         9. 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.


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         10. From and after the Second 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.


                            [Signature Page Follows]




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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: ____________________________



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                                   COMMITMENTS



       Bank                                        Revolving Commitment
       ----                                        --------------------
Bankers Trust Company                                  $20,000,000
Heller Financial, Inc.                                 $20,000,000
                                                       -----------
Total:                                                 $40,000,000





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