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                                                                   EXHIBIT 10.15

                           GROUP PURCHASING AGREEMENT

                                     Between

                                 AMERINET, INC.
                              2060 Craigshire Road
                                 P.O. Box 46930
                               St. Louis, MO 63146

                                       And

                        UNIVERSAL HOSPITAL SERVICES, INC.
                              1250 Northland Plaza
                              3900 West 80th Street
                           Bloomington, MN 55431-4442



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         This GROUP PURCHASING AGREEMENT ("Agreement") is made and entered into
as of the Effective Date (as defined on the signature page hereto) by and
between AmeriNet, Inc. ("AmeriNet"), and Universal Hospital Services, Inc.
("Supplier").

         WHEREAS, AmeriNet is a Delaware corporation, representing the member
institutions served by its Shareholders (which member institutions, both
singularly and collectively, are hereinafter referred to as "Participating
Institution(s)"); and

         WHEREAS, the Shareholders of AmeriNet are: Hospital Shared Services,
Warrendale, PA; Intermountain Health Care, Inc., Salt Lake City, UT; and Vector,
Providence, RI; and

         WHEREAS, AmeriNet and its Shareholders provide a broad portfolio of
agreements capable of serving all types of health care organizations, both
hospitals and non-hospitals alike; and

         WHEREAS, the philosophy of AmeriNet is to secure agreements with
suppliers that provide to the Participating Institutions products which are of
optimum quality, at appropriate pricing and with appropriate service; and

         WHEREAS, Supplier agrees to provide Equipment Rental, Medical (being
those products, accessories, equipment, and services more particularly described
in Addendum A hereto, all of which are hereafter referred to, both singularly
and collectively, as the "Product(s)") to Participating Institutions in
accordance with this Agreement; and

         WHEREAS, Supplier acknowledges that, except as set forth in Addendum A
to this Agreement, each Participating Institution meeting the membership
requirements of AmeriNet and its Shareholders shall be eligible for AmeriNet
programs and pricing and shall be entitled to purchase any Product in
accordance with the pricing, terms, and conditions defined in and for the
duration of this Agreement;

         NOW, THEREFORE, in consideration of the mutual promises and covenants
contained herein, and intending to be legally bound hereby, AmeriNet and
Supplier agree as follows:

SUPPLY REQUIREMENT OBLIGATIONS

1.   During the Contract Period (as defined in Paragraph 20), Supplier shall
     offer and sell the Products to the Participating Institutions identified on
     the Membership List (as defined in Paragraph 11 hereof), as and when such
     Membership List may be updated in accordance with Paragraph 11, on the
     terms and conditions set forth in Addendum A hereto and on the other terms
     and conditions set forth elsewhere in this Agreement. Except as set forth
     in Addendum A, Supplier guarantees that all the benefits of this Agreement
     shall be granted to each Participating Institution for the duration of the
     Contract Period. Participating Institutions may include hospitals, nursing
     homes, extended care facilities, health maintenance organizations, surgery
     centers and clinics, home health agencies, healthcare



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     clinics (including ambulatory care, radiology and outpatient clinics),
     physician offices, reference laboratories, closed door pharmacies, retail
     pharmacies and other educational and human service agencies.

2.   Supplier's execution of this Agreement shall constitute Supplier's
     guarantee of its ability to supply each Product to the Participating
     Institutions during the Contract Period, at the terms, conditions and
     prices specified herein.

3.   Supplier shall furnish only those Products specified in this Agreement and
     shall not furnish an alternate or substitute product or brand to any
     Participating Institution without receiving the prior written approval of
     such Participating Institution and/or AmeriNet.

4.   If Supplier distributes any Product to any Participating Institution
     through a dealer, distributor and/or wholesaler, Supplier shall allow
     access to the terms and pricing contained herein only to those dealers,
     distributors and/or wholesalers authorized in writing by AmeriNet (the
     "Authorized Dealers"). Supplier shall provide written notification of the
     terms, pricing and addenda of this Agreement to the Authorized Dealers at
     least sixty (60) days prior to the Commencement Date. Supplier shall also
     provide written notification of any subsequent revision to the terms,
     pricing and addenda of this Agreement to the Authorized Dealers at least
     sixty (60) days prior to the date that such revision takes effect. Supplier
     shall be responsible for all costs incurred by Authorized Dealers for
     credit and rebilling, or any cost otherwise incurred by such Authorized
     Dealers as a result of Supplier's failure to comply with this paragraph.
     Supplier agrees to obtain payment for any delivered Product directly from
     the Authorized Dealer to whom the Product was delivered. Supplier shall be
     solely responsible, at its sole cost, for resolving all disputes and
     controversies regarding any purchase order, invoice, Product, shipment
     and/or delivery date on a direct basis with the applicable Authorized
     Dealers without liability, participation or contribution by AmeriNet.

5.   If Supplier distributes any Product directly to any Participating
     Institution, rather than through an Authorized Dealer (or any other dealer,
     distributor and/or wholesaler), Supplier shall sell and ship such Product
     to the Participating Institution at the address the Participating
     Institution so specifies. Supplier shall obtain payment for any delivered
     Product directly from the Participating Institution to whom the Product was
     delivered. Supplier shall be solely responsible, at its sole cost, for
     resolving all disputes and controversies regarding any purchase order,
     invoice, Product, shipment and/or delivery date on a direct basis with the
     applicable Participating Institutions without liability, participation or
     contribution by AmeriNet.

6.   Supplier shall make prompt delivery of all Products to Participating
     Institutions. If Supplier fails to make any delivery of any Product to any
     Participating Institution, either directly or through an Authorized Dealer,
     on the date specified for delivery in the Participating Institution's
     purchase order accepted by Supplier or before such date if so authorized by
     the Participating Institution, such Participating Institution shall have
     the right to purchase the Product, or a similar competitive product from a
     third party, and Supplier shall reimburse the Participating Institution
     for the difference between the cost of such Product under this


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     Agreement and the actual delivered cost of the Product, or a similar
     competitive product, purchased from the third party.

7.   Title to a Product shall not pass to the Participating Institution at the
     time the Participating Institution accepts delivery of the Product. All
     risk of damage to or loss of a Product shall be assumed by Supplier until
     the Participating Institution accepts delivery of the Product.

8.   If any sales tax is due with respect to the sale of a Product hereunder, it
     shall be Supplier's sole responsibility to collect and pay such tax.
     Supplier shall defend, indemnify and hold harmless AmeriNet against any and
     all suits, claims and expenses wising out of any claimed failure to pay any
     sales tax on any Product sold under this agreement.

10.  Supplier shall furnish to AmeriNet, each Participating Institution, and
     each Authorized Dealer the then current Material Safety Data Sheet (MSDS)
     and other data as required by law for each product and upon request by
     AmeriNet or a Participating Institution.

MEMBERSHIP

11.  Upon execution of this Agreement, AmeriNet will provide the current list of
     Participating Institutions (the "Membership List") to Supplier. AmeriNet
     shall provide Supplier with any additions or deletions to the Membership
     List on at least a quarterly basis.

12.  Prior to the Commencement Date (as defined in Paragraph 20), Supplier shall
     enter each Participating Institution identified on the Membership List,
     which has a Supplier account number assigned into its reporting and
     information systems. The remaining Participating Institutions will be added
     as Supplier account numbers are assigned.

13.  Supplier represents and warrants to AmeriNet that Addendum B contains a
     correct and complete description of the process and procedure used by
     Supplier to recognize and enter into its reporting system the designation
     of a given facility as a Participating Institution with respect to the
     extension of the terms and conditions of this Agreement, the recognition
     and generation of Contract Activity Reports and/or the calculation and
     payment of Contract Administrative Fees (as such terms are hereinafter
     defined).

14.  Within thirty (30) days after entering the Membership List or any update
     thereto as provided in Paragraph 15, Supplier will give AmeriNet notice (a
     "Discrepancy Notice") identifying all Participating Institutions which,
     according to Supplier's records, are members of a group purchasing
     organization other than AmeriNet. If Supplier gives such notice, AmeriNet
     will review the status of such Participating Institution(s). To correct any
     discrepancy or clarify any uncertainty, AmeriNet (either on its own
     initiative or upon the reasonable request of


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     Supplier) may provide to Supplier a designation form substantially in the
     form attached hereto as Addendum C or Addendum D, as appropriate (each in
     "AmeriNet Membership Designation Form"), or any other contract-specific
     designation or commitment form approved by AmeriNet in accordance with
     Paragraph 19 duly executed by the Participating Institution, which
     designates AmeriNet as its "Primary" group purchasing organization for this
     Agreement. With respect to any Participating Institution as to which
     Supplier does not give AmeriNet a Discrepancy Notice within the time period
     required above, Supplier agrees to load and designate into its reporting
     and information systems AmeriNet as the "Primary" group purchasing
     organization for such Participating Institution. Regardless of whether a
     Participating Institution identifies AmeriNet as its "Primary" group
     purchasing organization, as a secondary group purchasing organization or
     otherwise, any purchase of any Product by any Participating Institution
     shall be subject to this Agreement, shall be sold to such Participating
     Institution on the terms and conditions contained herein, and shall be
     included in any Contract Activity Report and in the calculation and payment
     of the Contract Administrative Fee.

15.  As soon as practicable but in no event later than thirty (30) days after
     Supplier receives a signed AmeriNet Membership Designation Form or an
     update to the Membership List, Supplier shall update and correct its
     reporting and information systems as specified therein and shall notify
     each Authorized Dealer of any addition or deletion to the Membership List.
     If Supplier fails to comply with this paragraph, after the expiration of
     such 30-day period, Supplier shall be liable to AmeriNet for the Contract
     Administrative Fee for any Sale of any Product to any Participating
     Institution affected by the update.

16.  Upon Supplier's receipt from AmeriNet of any deletion of any institution
     from the Membership List, Supplier shall make such deleted institution
     ineligible for any benefits provided by this Agreement, effective as of the
     deletion date specified on the applicable Membership List update.

17.  Supplier shall promptly, but no later than ten (10) days after the
     effective date of any deletion or change, notify AmeriNet of any and all
     deletions and/or changes it has made to its reporting and information
     systems, or any notice it has provided to the Authorized Dealers with
     respect to the extension of the terms and conditions of the Agreement to
     Participating Institutions, the recognition and generation of Contract
     Activity Reports and/or the calculation and payment of Contract
     Administrative Fees. Supplier shall provide notice to AmeriNet of any
     deletion or change including, but not limited to (i) the recognition, or
     lack thereof, of any health care organization or facility as a
     Participating Institution, (ii) the generation or submission of the
     Contract Activity Report, (iii) the calculation of Sales, (iv) the
     calculation and payment of the Contract Administrative Fee, (v) the
     calculation and payment of any Discount, Surcharge or Processing Fee, or
     (vi) any notice it has provided to the Authorized Dealers for the
     Authorized Dealers to effect such a deletion or change.

19.  Supplier agrees that the signed AmeriNet Membership Designation Form shall
     ensure the appropriate recognition and reporting of AmeriNet as the
     "Primary" group purchasing organization of record for each Participating
     Institution under the terms of this Agreement. Except for those classes of
     trade specifically excluded as set forth in Addendum A, Supplier



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     agrees to recognize any health care organization which submits the AmeriNet
     Membership Designation Form as a Participating Institution of AmeriNet,
     entitled to the terms, conditions and pricing in accordance with this
     Agreement. In accordance with such recognition and no later than such time
     as provided herein. Supplier shall report to AmeriNet all subsequent
     contract activity along with the appropriate fees, the Contract Activity
     Reports and the Contract Administrative Fees for all Sales to such
     Participating Institution in accordance with the terms of this Agreement.

19.  If Supplier requires a contract-specific designation or commitment form
     (including, but not limited to, a bilateral agreement or letter of
     commitment) from a Participating Institution in addition or as an
     alternative to the AmeriNet Membership Designation Form (other than the
     contract-specific designation or commitment form attached hereto as
     Addendum K which AmeriNet hereby approves), any such contract-specific
     designation or commitment form must be submitted to and approved (as to
     form only) in advance and in writing by AmeriNet before Supplier
     distributes such document to any Participating Institution for approval or
     execution. Further, Supplier's contract-specific designation or commitment
     form shall designate AmeriNet as the "Primary" group purchasing
     organization of record for such Participating Institution under the terms
     of this Agreement. Supplier shall provide to AmeriNet a list of the
     Participating Institutions executing such contract-specific designation or
     commitment forms and shall promptly give AmeriNet notice of any additions
     or deletions to such list. Supplier acknowledges and agrees that any
     contract-specific designation or commitment form which is not approved (as
     to form) by AmeriNet in advance (in accordance with this Paragraph 19)
     shall not be valid or binding on the Participating Institution executing
     such contract-specific designation or commitment form; provided, however,
     that the invalidity of any such contract-specific designation or commitment
     form shall not affect Supplier's obligation to report Sales to the
     Participating Institution on a Contract Activity Report and to pay Contract
     Administrative Fees with respect thereto.

TERM AND TERMINATION

20.  The term of this Agreement shall commence as of June 1, 1999 through May
     31, 2002 (the "Commencement Date"), and shall continue thereafter through
     May 31, 2002 ("the End Date"), unless otherwise terminated pursuant to the
     provisions of this Agreement. The term of this Agreement of Thirty-Six
     months, or as it may be shortened pursuant hereto, is referred to as the
     "Contract Period".

21.  AmeriNet may terminate this Agreement if, in AmeriNet's sole and exclusive
     judgment:

     a)   Supplier fails to make any delivery of any Product to a Participating
          Institution within ten (10) days after the date specified for delivery
          in the Participating Institution's purchase order accepted by
          Supplier, and Supplier has not cured this failure of performance
          within five (5) days after receipt of notice thereof by AmeriNet, a
          Shareholder or the Participating Institution; or,

     b)   Supplier fails to make any delivery of any Product to a Participating
          Institution within ten (10) days after the date specified for delivery
          in the Participating Institution's



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          purchase order accepted by Supplier on more than __________ occasions
          (involving the same or different Participating Institution(s)) in a
          ___ month period, regardless of whether any such failure is cured in
          accordance with subparagraph (a) above; or,

     c)   Subject to Paragraph 64, Supplier is unable for any reason to supply
          Participating Institutions' reasonable requirements at any time during
          the Contract Period; or,

     d)   Supplier does not maintain adequate equipment, inventory or personnel
          to properly service Participating Institutions; or,

     e)   Supplier does not maintain the requisite insurance coverage specified
          in Paragraph 47 below; or,

     f)   Supplier has failed to notify AmeriNet and the Participating
          Institutions within seven (7) days after (i) Supplier becomes aware of
          any defect or condition which may render any Product in violation of
          the federal Food, Drug and Cosmetic Act or any other federal, state or
          local law, regulation or ordinance, or which in any way alters the
          specifications or quality of any Product, or (ii) Supplier receives
          any notification of any regulatory action or warning letter concerning
          any Product; or,

     g)   Supplier has failed to provide AmeriNet, any Participating
          Institution, or any Authorized Dealer with the most current Material
          Safety Data Sheet (MSDS) or other data with respect to any Product as
          required by law or within thirty (30) days after the request of
          AmeriNet or a Participating Institution for such document; or,

     h)   Supplier fails to pay any Contract Administrative Fee or fails to
          submit any Contract Activity Report, in each case within ninety (90)
          days after its respective due date; or

     i)   Supplier does not cure any error in reporting or payment identified as
          a result of an audit; or

     j)   Supplier otherwise breaches this Agreement and fails to cure such
          breach within ten (10) days after AmeriNet gives notice to Supplier
          thereof.

22.  In lieu of termination, AmeriNet, in its sole and exclusive judgment, may
     select alternate or additional supplier(s) to replace or supplement
     Supplier if (i) Supplier fails to make any delivery within a reasonable
     time period, (ii) if there have been multiple delinquencies in delivery,
     (iii) if Supplier is unable to supply Participating Institutions'
     reasonable requirements for the Products, and/or (iv) if Supplier does not
     maintain adequate equipment, inventory or personnel to properly service the
     Participating Institutions.

23.  AmeriNet reserves the right, in its sole and exclusive judgment, to
     terminate this Agreement immediately upon notice thereof to Supplier if (i)
     Supplier transfers assets in fraud of its creditors, (ii) Supplier makes an
     assignment for the benefit of its creditors, (iii) Supplier is the subject
     of any proceeding in bankruptcy instituted on behalf of or against
     Supplier, (iv) a receiver or trustee is appointed for Supplier's property,
     or (v) AmeriNet, in its sole



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     discretion, believes that Supplier is financially unable to carry out
     adequately its obligations under this Agreement.

24.  Supplier may terminate this Agreement if AmeriNet breaches a material term
     of this Agreement and fails to cure such breach within thirty (30) days
     after Supplier gives notice to AmeriNet thereof.

25.  Upon termination of this Agreement for any reason, AmeriNet and Supplier
     shall have the following rights and obligations which shall survive the
     termination of this Agreement:

     a)   Termination of this Agreement shall not release either party from any
          obligation arising under this Agreement prior to its termination,
          including, but not limited to, Supplier's obligation to pay in full to
          AmeriNet the Contract Administrative Fee with respect to any Sale of
          any Product through the date of termination of this Agreement and any
          Sale of any product or service which is the subject of a separate
          bilateral agreement or letter of commitment between Supplier and any
          Participating Institution entered into at any time during the Contract
          Period (a "Bilateral Product") through the date of termination of
          such bilateral agreement or letter of commitment;

     b)   Supplier shall continue to honor each order for each Product from each
          Participating Institution and from each Authorized Dealer up to the
          effective date of termination and for a period of thirty (30) days
          thereafter, which orders shall be subject to the pricing, terms and
          conditions of this Agreement;

      c)  Supplier and AmeriNet shall not use, publish or disclose or cause
          anyone else to use, publish or disclose any confidential information
          obtained or learned by either party as a consequence of this
          Agreement; provided, however, that AmeriNet may disclose such
          confidential information to the Shareholders, the Participating
          Institutions and any employee or advisor of AmeriNet assisting
          AmeriNet in its evaluation or interpretation of this Agreement.
          However, the above restrictions on disclosure and use shall not apply
          to any information which (i) presently is or hereafter becomes part of
          the public domain without breach of this Agreement, (ii) is already in
          the non-disclosing party's possession at the time of disclosure, (iii)
          comes into the non-disclosing party's possession from a third party
          without breach of this Agreement, (iv) is independently developed by
          the non-disclosing party or a third party without resource to or
          utilization of any portion of the confidential information imparted or
          transmitted herein, or (v) is required by law or court order to be
          disclosed.

FEE AND REPORTING REQUIREMENTS

26.  During the first twelve months of this agreement, Supplier agrees to remit
     to AmeriNet a quarterly administration fee equal to two-percent of all
     rental revenue of those Participating Institutions which have signed the
     Supplier's Letter of Commitment. During subsequent years of this agreement,
     Supplier agrees to remit to AmeriNet a quarterly administration fee equal
     to one-percent applied to all rental revenue of those Participating
     Institutions which have signed the Supplier's Letter of Commitment and
     three percent on growth business. Growth business is defined as rental
     revenue which exceeds the average quarter revenue for the first twelve
     months of the Agreement. The average quarter is defined as the first twelve
     month's revenue, divided by twelve and multiplied by three. All
     administration fees will be paid within 45 days of each quarter.


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27.  Supplier shall pay the Contract Administrative Fee in U.S. Dollars by
     check or bank draft. Checks are to be made payable to "AmeriNet, Inc."
     Supplier will remit the Contract Administrative Fee to AmeriNet within
     forty-five (45) days after the close of each Reporting Period. "Reporting
     Period" shall mean each calendar quarter.

28.  Supplier shall include the following information when submitting a Contract
     Administrative Fee to AmeriNet. This information must appear on each
     Contract Administrative Fee payment notice (e.g., check stub):

     a)   Supplier's name (If a parent or affiliate corporation is making a
          payment on behalf of Supplier, Supplier's name as it appears on this
          Agreement must be identified on the face of the check stub or on the
          payment notice); and

     b)   Contract number as assigned by AmeriNet; and

     c)   Reporting Period for which the Contract Administrative Fee is being
          paid (e.g., 1/1/99 - 1/31/99).

29.  Supplier shall report all Sales under this Agreement to AmeriNet (the
     "Contract Activity Report"). Supplier shall submit the Contract Activity
     Report to AmeriNet within thirty (30) days after the close of each
     Reporting Period.

30.  Supplier shall include the following information in each Contract Activity
     Report:

     a)   Supplier's name, address and zip code;

     b)   Contract number as assigned by AmeriNet;

     c)   Reporting Period covered by the Contract Activity Report (e.g., 1/1/99
          - 1/31/99);

     d)   Sales to each Participating Institution shall be reported as follows:

          (i)  For the submission of Contract Activity Reports, Sales to each
               Participating Institution are to be reported for all Products
               included in this Agreement, in total by the contract number
               assigned by AmeriNet, not by line or product item detail.

          (ii) Supplier may report detailed Sales activity by line or product
               item detail if so authorized by AmeriNet.

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          (iii) state and zip code, and AmeriNet customer number. Each
                Participating Institution's Hospital Identification Number (HIN)
                may be substituted for name, address and zip code.

     e)   Total Sales for all Participating Institutions must be summarized and
          reported.

31.  Supplier shall submit each Contract Activity Report in accordance with
     Addendum E. If Addendum E indicates that Supplier shall submit the Contract
     Activity Report in electronic form, Supplier must comply with the
     specifications for electronic filing specified in Addendum E, as it may be
     amended by AmeriNet from time to time. If Addendum E indicates that
     Supplier shall submit the Contract Activity Report in printed, hardcopy
     form, or if Supplier submits the Contract Activity Report in an electronic
     form that does not comply with the AmeriNet filing specifications set forth
     in Addendum E, Supplier shall pay AmeriNet an incremental one-quarter of
     one percent (.25%) processing fee (the "Processing Fee") for each Contract
     Activity Report so filed. The Processing Fee shall be calculated by
     multiplying the Sales for the Reporting Period covered by such Contract
     Activity Report by .0025. The Processing Fee shall be added to and remitted
     with the payment of the Contract Administrative Fee applicable to such
     Reporting Period.

32.  A discount of one percent (1%) (the "Discount") shall apply to the Contract
     Administrative Fee if the Contract Administrative Fee and the Contract
     Activity Report are received by AmeriNet within fifteen (15) days after the
     close of the Reporting Period to which they relate. The discount shall be
     calculated by multiplying the Contract Administrative Fee for such
     Reporting Period by .01 and then subtracting the result of such calculation
     from the Contract Administrative Fee for such Reporting Period.

33.  Supplier shall pay a late payment penalty surcharge ("Surcharge") of one
     and one-half percent (1-1/2%) per month if the Contract Administrative Fee
     and/or the Contract Activity Report with respect to a given Reporting
     Period have not been received by AmeriNet within thirty (30) days after
     the close of such Reporting Period. The Surcharge is calculated by
     multiplying the Contract Administrative Fee for the Reporting Period for
     which the Contract Activity Report and/or the Contract Administrative Fee
     have not been submitted by .015, and then multiplying the result of such
     calculation by a fraction, the numerator of which is total number of days
     that the Contract Activity Report and/or the Contract Administrative Fee is
     delinquent, and the denominator of which is thirty (30).

34.  If the Contract Administrative Fee has not been received by AmeriNet within
     ninety (90) days after the end of the Reporting Period to which it relates,
     AmeriNet may invoice Supplier for the Contract Administrative Fee estimated
     by AmeriNet to be due for such Reporting Period. Supplier shall pay such
     estimated Contract Administrative Fee within ten (10) days after receipt of
     AmeriNet's invoice, if Supplier has not previously paid the Contract
     Administrative Fee for such Reporting Period. Invoice by AmeriNet or
     payment of such estimated Contract Administrative Fee by Supplier shall not
     relieve Supplier of its obligation to submit the Contract Activity Report
     applicable to such Reporting Period and to pay in full the actual Contract
     Administrative Fee owed with respect to such Reporting Period and any
     Surcharge applicable thereto.


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35.  During the Contract Period and within 180 days thereafter, AmeriNet retains
     the right to audit or to have its agents audit Supplier's records. Such
     audits may include, but shall not be limited to, tracking of Product Sales,
     Contract Administrative Fees, Contract Activity Reports, Supplier's costs
     and Supplier's freight charges. If AmeriNet elects to conduct an audit,
     Supplier agrees to make available during normal business hours such of its
     documents and personnel as AmeriNet may reasonably request in order to
     conduct such audit. If any audit determines (i) that the calculation,
     reporting and/or payment of any Contract Administrative Fee was in error,
     and/or (ii) that any overcharge was incurred by any Participating
     Institution, Supplier shall provide a written response or explanation,
     correct any error, and remit any monies due within fifteen (15) days after
     receiving notice of the error or overcharge. If the audit reveals an error
     or overcharge with respect to any amount described in the foregoing clause
     (i) or clause (ii) which in the aggregate exceed one percent (1%) of such
     amount, then, in addition, Supplier shall pay AmeriNet's out-of-pocket
     costs of such audit.

36.  Every notice, Contract Activity Report and other communication to AmeriNet
     in connection with this Agreement shall be in writing. Each such notice,
     Contract Activity Report and other communication, and each payment and
     Contract Administrative Fee hereunder, shall be sent to AmeriNet at the
     following address until otherwise notified by AmeriNet:

                                 AmeriNet, Inc.
                               Attn.: Joe Raftery
                              2060 Craigshire Road
                                 P.O. Box 46930
                               St. Louis, MO 63146

37.  Unless subsequently notified by Supplier, every notice and other
     communication to Supplier in connection with this Agreement, including
     reporting discrepancies and problem resolution, shall be in writing and
     shall be addressed to:



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                        Universal Hospital Services, Inc.
                              Attn: James T. Ekbom
                              1250 Northland Plaza
                              3800 West 80th Street
                           Bloomington, MN 55431-4442

     a)   Individual responsible for entering all Participating Institution
          information into Supplier's pricing system and database to guarantee
          access to and implementation of the Agreement's terms and pricing:

               Name: Andy Kohls
                    ------------------------------------------------------------
               Title: Accounts Receivable - Control
                     -----------------------------------------------------------
               Address: 3800 W 80th Street, Suite 1250
                       ---------------------------------------------------------
               City/State/Zip: Bloomington, MN 55431
                              --------------------------------------------------
               Phone: (612) 893-3200               Ext: (voice mail = ext. 3265)
                     -----------------------------     ------------------------
               Email: akohls@uhs.com
                     -----------------------------------------------------------

     b)   Individual responsible for compilation and submission of Contract
          Activity Reports to AmeriNet:

               Name: Andy Kohls
                    ------------------------------------------------------------
               Title:
                     -----------------------------------------------------------
               Address:
                       ---------------------------------------------------------
               City/State/Zip:
                              --------------------------------------------------
               Phone:                              Ext:
                     -----------------------------     ------------------------
               Email:
                     -----------------------------------------------------------

     c)   Individual responsible for calculation and payment of Contract
          Administrative Fee to AmeriNet:

               Name: Andy Kohls
                    ------------------------------------------------------------
               Title:
                     -----------------------------------------------------------
               Address:
                       ---------------------------------------------------------
               City/State/Zip:
                              --------------------------------------------------
               Phone:                              Ext:
                     -----------------------------     ------------------------
               Email:
                     -----------------------------------------------------------

INFORMATION SYSTEMS

38.  Supplier shall support the exchange of data and information, including but
     not limited to Sales reporting, Membership Lists, Product catalogs and
     pricing information, via electronic media and electronic data interchange
     ("EDI"), to the extent provided and in accordance with the specifications
     set forth in Addendum E and Addendum F.



AmeriNet, Inc.                                                 Revised: 12/01/98
Group Purchasing Agreement

                                       12
<PAGE>   13
INFORMATION SYSTEMS

39. Supplier shall support the exchange of data and information, including but
    not limited to Sales reporting, Membership Lists, Product catalogs and
    pricing information, via electronic media and electronic data interchange
    ("EDI"), to the extent provided and in accordance with the specifications
    set forth in Addendum E and Addendum F.

40. Where applicable, Supplier shall support the UPN Initiative as promulgated
    in the Joint Communique dated February 23, 1998 by the Healthcare EDI
    Coalition ("HEDIC") to the extent provided in Addendum G. The purpose of the
    UPN Initiative is to establish the use of Universal Product Numbers ("UPN")
    throughout the healthcare industry at each package level or inventory unit
    of the Product. Where applicable, Supplier shall establish and implement
    Universal Product Numbers and machine-readable bar codes on the Products to
    the extent provided in Addendum G.

41. Supplier shall support the development of electronic commerce on the
    Internet by and among AmeriNet, the Shareholders, the Participating
    Institutions and Supplier to the extent provided in Addendum H.

ASSIGNMENT

42. AmeriNet has entered into this Agreement with Supplier because of the
    commitments and representations Supplier is making in this Agreement and
    further because of AmeriNet's confidence in Supplier, which confidence is
    personal in nature. Consequently, Supplier shall not assign or delegate any
    of its rights or obligations hereunder without the prior written consent of
    AmeriNet; an "assignment" by Supplier shall be deemed to include (i) a
    change in the identity of the person(s) or entity(ies) owning a majority of
    the issued and outstanding voting securities of Supplier, whether in a
    single transaction or a series of related transactions, and (ii) a transfer
    of this Agreement by operation of law due to the merger or consolidation of
    Supplier with another entity. Any attempt by Supplier to assign any of its
    rights or delegate any of its duties hereunder without the prior written
    consent of AmeriNet shall be null and void and shall entitle AmeriNet, at
    its sole and exclusive option, to terminate this Agreement in its entirety.
    In addition, any such attempted assignment by Supplier shall entitle each
    Participating Institution, at its sole and exclusive option, to cease
    purchasing any and all Products from Supplier and to begin purchasing such
    Products from such other manufacturers or suppliers as the Participating
    Institution may select. AmeriNet may freely assign and delegate any of its
    rights and obligations under this Agreement without restriction. No
    assignment permitted by this paragraph shall release the assigning party
    from its duties and obligations under this Agreement without the express
    written consent thereto of the other party. Subject to the limitations on
    assignment set forth in this paragraph, this Agreement will apply to, be
    binding in all respects upon, and inure to the benefit of the successors and
    permitted assigns of the parties.

AmeriNet, Inc.                                                 Revised: 12/01/98
Group Purchasing Agreement


                                       13
<PAGE>   14


WARRANTIES AND INDEMNIFICATION

45. Supplier has made certain representations and warranties to AmeriNet in
    Addendum I with respect to each Product's ability to correctly identify,
    manipulate, and calculate using dates outside of the 1900 - 1999 year range
    ("Year 2000 Compliant").

    Supplier agrees to indemnify and hold harmless AmeriNet, its Shareholders,
    Participating Institutions, and all of their respective subsidiaries,
    affiliates, directors, officers, employees and agents and all of their
    respective successors and permitted assigns, from and against any and all
    claims, actions, suits, proceedings, liabilities, costs and expenses,
    including reasonable attorney's fees arising out of or resulting from
    personal injury, or property damage, or loss of property caused by the
    negligence of Supplier and arising our of or caused by Suppliers'
    performance of services under the Agreement.

    AmeriNet, its Shareholders, and all of their respective subsidiaries,
    affiliates, directors, officers, employees and agents, and all of their
    respective successors and permitted assigns, agrees to indemnify and hold
    harmless

AmeriNet, Inc.                                                 Revised: 12/01/98
Group Purchasing Agreement

                                       14

<PAGE>   15

    Supplier from and against any and all claims, actions, suits, proceedings,
    liabilities, costs and expenses, including reasonable attorney's fees
    arising out of or resulting from personal injury, or property damage, or
    loss of property caused by the negligence of Participating Institution and
    arising out of or caused by Participating Institution of services under
    this Agreement.

INSURANCE

46. At all times during this Agreement, Supplier shall maintain (a) Worker's
    Compensation insurance covering its full liability under the appropriate
    states' statutes and (b) comprehensive general (and professional, if
    applicable) liability insurance in an amount at least equivalent to the
    standard in Supplier's industry. Supplier shall keep and maintain the
    foregoing insurance in force during the term of the Agreement and thereafter
    until the expiration of each statute of limitations applicable to
    liabilities of the kind covered by such insurance. Supplier shall
    immediately (and no later than thirty (30) days prior to the effective date
    of any change) notify AmeriNet of any changes in the foregoing insurance,
    including, but not limited to, any cancellation or material change in
    coverage. Upon request of AmeriNet, Supplier shall provide evidence of
    insurance coverage as specified above.

PRODUCT MARKETING AND GPO-COMPLIANCE REQUIREMENTS

47. In the performance of its duties and obligations under this Agreement,
    Supplier shall at all times comply with all applicable federal, state and
    local laws, statutes, regulations, rules, orders and ordinances now in
    effect or as hereafter enacted, amended or promulgated.

49. Upon request by AmeriNet, Supplier shall provide, at no charge, literature,
    training and marketing assistance to lawfully promote and support the sale
    and utilization of each Product by Participating Institutions. Supplier
    agrees to participate with AmeriNet in the design, development and
    implementation of a launch program, with mutually agreed upon actions and
    timelines, and to promote and support the sale and utilization of each
    Product by Participating Institutions. Supplier also agrees to notify and
    train its sales representatives responsible for implementing this Agreement
    to promote and support the sale and utilization of each Product by
    Participating Institutions.

AmeriNet, Inc.                                                 Revised: 12/01/98
Group Purchasing Agreement

                                       15
<PAGE>   16


51. During the Contract Period, Supplier agrees that the price paid by any
    Participating Institution for any Product under this Agreement shall be
    equal to or lower than the price that would be paid by that Participating
    Institution under the terms of any other agreement which Supplier has
    offered to any other group, person or entity of similar membership numbers
    and contract compliance percentages.

53. Supplier will not persuade or induce any Participating Institution to
    terminate its status or relationship with AmeriNet by offering more
    attractive contract prices, terms or conditions to such Participating
    Institution, or in any other manner or form whatsoever. A breach of this
    paragraph will constitute sufficient cause for AmeriNet to terminate this
    Agreement and/or to seek damages from Supplier for loss of all actual and
    prospective Contract Administrative Fees resulting directly or indirectly
    from such breach.

54. If at any time during the Contract Period, Supplier develops and markets an
    improvement to any Product, Supplier shall add such Product improvement to
    this Agreement within thirty (30) days, subject to AmeriNet's approval of
    the terms and pricing of the Product improvement. Notwithstanding the
    foregoing, AmeriNet's acceptance of a Contract Administrative Fee with
    respect to any Product improvement shall not constitute the acceptance and
    inclusion by AmeriNet of such Product improvement as a Product under this
    Agreement without AmeriNet's express written consent thereto.

55. If at any time during the Contract Period, Supplier develops a product line
    extension or a product addition (a "New Product"), Supplier agrees that it
    shall offer AmeriNet the right to include such New Product in an amendment
    to this Agreement or in a new agreement. Supplier shall give notice of such
    New Product to AmeriNet, which notice shall describe the New Product and its
    use in reasonable detail. If AmeriNet is interested in including the New
    Product in its contract portfolio, AmeriNet and Supplier agree to negotiate
    terms and pricing relating to the New Product. Notwithstanding the
    foregoing, AmeriNet's acceptance of a Contract Administrative Fee with
    respect to any New Product shall not constitute the acceptance and inclusion
    by AmeriNet of such New Product as a Product under this Agreement without
    AmeriNet's express written consent thereto.

56. Supplier and AmeriNet understand and agree that new clinical developments
    in patient care or new regulatory agency restrictions may result in changed
    conditions. If, in the sole and exclusive judgment of AmeriNet, this
    Agreement or Supplier's Products do not adequately meet such changed
    conditions, AmeriNet shall have the option to pursue alternate or additional
    contracts and/or suppliers.

57. Supplier shall support AmeriNet's private label program to the extent
    provided in Addendum J.

58. Many Participating Institutions are providers under the federal Medicare
    programs, and, as a consequence, the provisions of Section 952 of the
    Omnibus Reconciliation Act of 1980 may be applicable to this Agreement.
    Therefore, until the expiration of four years after the final furnishing of
    Products under this Agreement, Supplier shall make available, upon written
    request of the Secretary of the U.S. Department of Health and Human
    Services, the U.S.

AmeriNet, Inc.                                                 Revised: 12/01/98
Group Purchasing Agreement


                                       16
<PAGE>   17


    Comptroller General, or such Secretary's or Comptroller's authorized
    representative, this Agreement and Supplier's books, documents and records
    that are necessary to certify the nature and extent of the costs of the
    Products purchased and sold hereunder. Supplier shall obtain a written
    contractual commitment from each of Supplier's subcontractors to do the
    same.

59. Except as way be required by law or as reasonably required to conduct their
    respective businesses, AmeriNet, its Shareholders and Supplier shall keep
    confidential the details of this Agreement. AmeriNet and Supplier may
    announce the execution of this Agreement and may disclose other information,
    such as the overall savings to be realized from this Agreement, subject to
    the written approval of the other party.

60. The following Addendums:

      Addendum A (Product Data Sheet)

      Addendum B (Participating Institution Designation Procedure)

      Addendum C (AmeriNet Membership Designation Form - Exclusive Group)

      Addendum D (AmeriNet Membership Designation Form - Program Select)

      Addendum E (Supplier Contract Reporting)

      Addendum F (Supplier EDI Support and Reporting)

      Addendum G (Supplier Labeling Standards Support)

      Addendum H (Supplier Support of Electronic Commerce)

      Addendum I (Supplier Year 2000 Compliance)

      Addendum J (Private Label Program Support)

      Addendum K (Contract-Specific Designation or Commitment Form)

      Addendum L (Value Added)

    shall be considered an integral and binding component of this Agreement and
    are hereto incorporated by this reference and made a part of this Agreement.
    In the event of any actual or perceived inconsistencies or conflicts between
    this Agreement and any Addendums to this Agreement, the provisions of this
    Agreement shall govern. This Agreement, together with the foregoing
    Addendums, will constitute the full and complete Agreement between the
    parties as to the term outlined herein. This Agreement supersedes and
    cancels in their entirety any and all previous agreements, discussions,
    negotiations, commitments and obligations of any sort whether written or
    oral, previously existing between AmeriNet and Supplier with respect to the
    subject matter hereof

OTHER

61. Supplier represents and warrants that it prepared its proposal to AmeriNet
    without any collusion whatsoever among or between any other potential or
    actual contractors of AmeriNet.

62. It is understood and agreed that the parties hereto are independent
    contractors, and nothing in this Agreement shall be construed so as to
    constitute the parties as partners or joint venturers. Neither party has any
    right or authority, express or implied, to assume or create any obligation
    on behalf of the other party, or to bind or commit the other party to third

AmeriNet, Inc.                                                 Revised: 12/01/98
Group Purchasing Agreement

                                       17
<PAGE>   18


    parties, in any manner. No party shall hold itself out as having any
    authority or relationship in contravention of this paragraph.

63. If one or more of the provisions of this Agreement, or the application
    thereof, is determined to be invalid or unenforceable, the remainder of this
    Agreement shall remain in full force and effect, and the provisions deemed
    invalid or unenforceable replaced with valid and enforceable provisions
    which achieve the intent of Supplier and AmeriNet in entering into this
    Agreement.

64. If AmeriNet or Supplier is unable to discharge any obligations imposed upon
    it by this Agreement, the failing party shall not be liable should such
    failure be found to be a result of force majeure. For the purpose of this
    paragraph, force majeure shall include, but not be limited to, an act of
    God, fire, act of war, public riot, natural disaster, or labor disturbance.
    AmeriNet may select an alternate or additional supplier(s) to replace or
    supplement Supplier for the Products for the period during which Supplier is
    unable to discharge or fulfill its obligations under this Agreement as a
    result of force majeure.

65. No amendment, modification or alteration of the terms of this Agreement
    shall be binding unless the same is in writing and is duly executed by the
    parties hereto, except that any provision of this Agreement may be waived in
    writing at any time by the party which is entitled to the benefit of such
    provision. No waiver of any provision of this Agreement shall be deemed to
    or shall constitute a waiver of any other provision hereof (whether or not
    similar). Except as expressly provided in this Agreement, no delay on the
    part of any party in exercising any right, power or privilege shall operate
    as a waiver thereof. The waiver by either party of any breach or default by
    the other party shall not be construed to be either a waiver of any
    subsequent breach or default of any such provision, of the same or different
    kind, or a waiver of the provision itself.

66. All section headings and the use of a particular gender contained herein are
    for convenience only and shall in no way modify or restrict any of the terms
    or provisions hereof, or affect the meaning or interpretation of this
    Agreement.

67. This Agreement shall be signed by a duly authorized representative or agent
    of Supplier, such signature to constitute proof of that person's authority
    to bind Supplier. This Agreement shall be signed by a duly authorized
    representative or agent of AmeriNet, such signature to constitute proof of
    that person's authority to bind AmeriNet.

68. This Agreement shall be construed and enforced in accordance with the laws
    of the State of Missouri as it applies to contracts negotiated, executed,
    delivered and performed solely within such jurisdiction. Any action or
    proceeding seeking to enforce any provision of, or based on, arising out of,
    or in any way related to, any right, obligation or matter set forth in this
    Agreement shall be brought in the courts of the State of Missouri (or, if
    jurisdiction is appropriate, the U.S. District Court for the Eastern
    District of Missouri), and each of the parties consents to the jurisdiction
    of such courts (and of the appropriate appellate courts) in any such action
    or proceeding and waives any objection to jurisdiction and venue laid
    therein. Process in



AmeriNet, Inc.                                                  Revised 12/01/98
Group Purchasing Agreement

                                       18
<PAGE>   19


    any action or proceeding referred to in the preceding sentence may be served
    on any party anywhere in the world.

69. This Agreement may be executed in two or more counterparts, each of which is
    an original and all of which together shall be deemed to be one and the same
    instrument. This Agreement shall become binding when one or more
    counterparts taken together shall have been executed and delivered by each
    of the parties hereto to the other.

70. See Addendum L, Value Added.


            [the remainder of this page is intentionally left blank]


AmeriNet, Inc.                                                  Revised 12/01/98
Group Purchasing Agreement

                                       19
<PAGE>   20


IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed as of the date set forth below the signature of AmeriNet's authorized
representative (the "Effective Date").

SUPPLIER NAME:                        Universal Hospital Services, Inc.
                                      ------------------------------------------
ADDRESS:                              3800 W 80th Street
                                      ------------------------------------------
                                      Suite 1250
                                      ------------------------------------------
                                      Bloomington, MN 55431
                                      ------------------------------------------

                                      ------------------------------------------

AUTHORIZED REPRESENTATIVE:

BY:                                   /s/ GARY PRESTON
                                      ------------------------------------------
PRINTED NAME:                         Gary Preston
                                      ------------------------------------------
TITLE:                                Vice President
                                      ------------------------------------------
DATE:                                 02-04-99
                                      ------------------------------------------

NAME:                                 AMERINET, INC.
ADDRESS:                              2060 Craigshire Road
                                      P.O. Box 46930
                                      St. Louis, MO 63146

AUTHORIZED REPRESENTATIVE:

BY:                                   /s/ JOSEPH B. RAFTERY
                                      ------------------------------------------
PRINTED NAME:                         Joseph B. Raftery
                                      ------------------------------------------
TITLE:                                Senior Contract Manager
                                      ------------------------------------------
DATE:                                 3/31/99
                                      ------------------------------------------


AMERINET SHAREHOLDERS

[HOSPITAL SHARED SERVICES LOGO]  [INTERMOUNTAIN HEALTH CARE LOGO]  [VECTOR LOGO]

AmeriNet, Inc.                                                  Revised 12/01/98
Group Purchasing Agreement

                                     20