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                              CONSULTING AGREEMENT

        This Consulting Agreement ("Agreement") is entered into as of the 12th
day of May, 1998, between PETER GLADKIN, a resident of the State of California
("Consultant"), and APACHE MEDICAL SYSTEMS, INC., a Delaware corporation
("APACHE").

        WHEREAS, APACHE desires to retain Mr. Gladkin to provide certain
management consulting services;

        WHEREAS, Mr. Gladkin desires to provide such consulting services to
APACHE;

        NOW, THEREFORE, in consideration of the mutual promises, conditions, and
covenants herein, the Parties agree as follows:

        1. Term of Agreement. Subject to Section 10 of this Agreement, the term
of this Agreement shall be May 4, 1998, through June 30, 1998, unless extended
in writing by the Parties.

        2. Services to be Provided. Consultant shall devote approximately 50 to
80 percent of his professional time assisting APACHE in developing strategic
planning initiatives, developing and achieving financial projections, and
evaluating APACHE's management and organizational needs as requested by, and in
accordance with direction received from, APACHE's Board of Directors.

        3. Compensation for Services Rendered. APACHE agrees to pay the
Consultant a fixed per diem amount of $600.00 per day for each day that he
spends a substantial amount of time traveling and performing services under this
Agreement, irrespective of whether those services are rendered in Virginia,
California, Illinois or elsewhere.

           a. Consultant shall not be eligible to participate in or receive
benefits under the employee benefit plans that APACHE maintains for its
employees during the term of this Agreement, including, but not limited to,
health benefits, paid vacation and sick leave, life insurance and medical
benefits.

           b. APACHE shall pay Consultant $20,000.00 ($10,000.00 on May 15 and 
$10,000.00 on June 15) as reimbursement for his air travel expenses between
Washington and California during the term of this Agreement, and for which
receipts will not be required. Additionally, APACHE shall reimburse Consultant
for verified and reasonable expenses that he incurs while performing services
for APACHE during the term of the Agreement, including expenditures for hotels,
meals, other air travel, local transportation and other business expenses in
accordance with APACHE's standard travel reimbursement policy.

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        4. Payment of Taxes. By execution of this Agreement, Consultant
certifies that he is an independent contractor for federal and/or state
employment tax purposes. Consultant understands and agrees that he is
responsible for the payment of all taxes, including federal, state and local
employment taxes arising out of his activities and receipt of payment under this
Agreement. Pursuant to this Agreement, APACHE will not withhold, and is not
responsible for, federal or state employment or other taxes that may be assessed
and owed on the amounts that Consultant earns under this Agreement.

        5. Independent Contractor Relationship. Consultant shall provide
professional services to APACHE as an independent contractor. He shall not be
considered an employee of APACHE during the term of this Agreement within the
meaning of any federal, state or local law, or within the meaning or application
of APACHE's employee benefit plans and related benefit policies and practices.
Consistent with his status as an independent contractor, Consultant may continue
to engage in other trade or business during the term of this Agreement.

        6. No Conflict of Interest. Consultant represents that to the best of
his knowledge and belief, his performance of services under this Agreement will
not violate the terms of any non-competition or other employment agreement that
he may have executed or be subject to, and shall immediately advise APACHE in
writing should he become aware of, or should any claim be made of, such a
violation. Consultant further represents that his performance of services in
connection with Consultant's other consulting or employment relationships, if
any, shall not constitute a conflict of interest with APACHE, and that
Consultant shall advise APACHE in writing should such a conflict develop.
"Conflict of interest" shall mean the performance of services in competition
with APACHE's products and services, including its critical care and other
disease state outcomes management applications, its health care outcomes
research activities, and the consulting activities of National Health Advisors.

        Additionally, Consultant agrees that he will not knowingly use or
disclose to APACHE any confidential and/or proprietary information that he may
have obtained from a prior employer concerning that employer's business or
operations in performing services for APACHE under this Agreement.

        7. Ownership of Confidential and Proprietary Information. All
Confidential Information which becomes known to Consultant as a result of
performing services for APACHE shall be the sole property of APACHE, and APACHE
shall be the sole owner of all patents, copyrights and other rights in
connection therewith, including but not limited to the right to make application
for statutory protection. Consultant agrees not to use or disclose any
Confidential Information or anything directly relating to it without APACHE's
written consent, except as may be necessary in the ordinary course of performing
his consulting services for APACHE's benefit under this Agreement.
Notwithstanding these 



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commitments, Consultant shall remain free to use (a) information in the public
domain not as a result of a breach of this Agreement and (b) his own skill,
knowledge, know-how and experience.

        For purposes of this Paragraph, Confidential Information shall include,
but not be limited to, information that has been created, discovered, developed,
or otherwise become known to APACHE (including, without limitation, information
created, discovered, developed, or made known by Consultant during the period of
this Agreement) and/or in which property rights have been assigned or otherwise
conveyed to APACHE, which information has commercial value in the business in
which APACHE is or may become engaged. By way of illustration, but not
limitation, Confidential Information includes APACHE trade secrets, processes,
structures, formulas, data and know-how, improvements, inventions, product
concepts, techniques, marketing plans, strategies, forecasts, customer lists and
information about APACHE's employees and/or consultants (including without
limitation, the compensation, job responsibility and job performance of such
employees and/or consultants). Additionally, Confidential Information shall
include certain information that has been made known to APACHE from third
parties, including, but not limited to, patient identifying information,
physician identifying information, information that would link a client's name
to individual data, and any information protected by a confidentiality agreement
or terms and conditions of an agreement regarding confidentiality.

        8. Inventions, Patents, Trademarks and Copyrights.

           a. Consultant hereby assigns to APACHE the entire right, title
and interest in and to all Work Product produced by him in rendering services
under this Agreement. "Work Product" is defined as work product, including but
not limited to plans, programs, databases, writings, designs, models, drawings,
design inventions and any other inventions (including all proprietary rights in
any of the foregoing) made, conceived, or reduced to practice or adhered by the
Consultant, either solely or jointly with others, in the performance of this
Agreement or with the use of information, materials or facilities of APACHE
received or used by Consultant during the term of this Agreement or any
extensions or renewals of this Agreement.

           b. Consultant agrees promptly to disclose to APACHE all Work
Product conceived, or reduced to practice or adhered by the Consultant as set
forth in a. above.

           c. Consultant's Work Product shall be a work for hire, and APACHE
shall own the copyright thereto. The Consultant agrees to sign, execute and
acknowledge or cause to be signed, executed, and acknowledged without cost, but
at the expense of APACHE, any and all documents and to perform such acts as may
be reasonably necessary, useful or convenient for the purpose of securing to


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APACHE or its nominees, patent, trademark, copyright or other proprietary rights
protection throughout the world in the Work Product.

        9. Termination. This Agreement may be terminated by either Party upon
fourteen (14) days written notice to the other Party. Such notice shall be
forwarded by registered mail to the following address:

<TABLE>
              <S>                       <C>
               Notice to APACHE:        Mr. Thomas W. Hodson
                                        Chairman of the Board
                                        c/o NeuroSource, Inc.
                                        515 N. State Street
                                        Suite 1700
                                        Chicago, IL  60610
                                
               Notice to Consultant:    Mr. Peter Gladkin
                                        P.O. Box 531
                                        Cedar Glenn, CA  92321
</TABLE>

        Consultant shall notify APACHE by certified mail of any change in his
address, and thereafter, APACHE shall forward any notices under this Agreement
to Consultant at such new address.

        10. Assignment. This Agreement may not be transferred, subcontracted or
assigned by Consultant to any third party.

        11. Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Virginia.


                                            APACHE MEDICAL SYSTEMS, INC.
                                   
/s/ PETER GLADKIN                           By: /s/ THOMAS W. HODSON
-----------------------------------            ---------------------------------
PETER GLADKIN                      
                                            Its: CHAIRMAN OF THE BOARD
                                                --------------------------------

Date:  5/20/98                              Date:  5/20/98
     ------------------------------              -------------------------------




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