<PAGE>

                                SECOND AMENDMENT TO
                                CONSULTING AGREEMENT


     This Second Amendment is made and entered into effective as of the 1st 
day of September, 1998 by and between Oxboro Medical International, Inc., a 
Minnesota corporation (the "Company"), and Larry A. Rasmusson ("Rasmusson" or 
"Consultant").

                                  R E C I T A L S

     WHEREAS, the Company and Rasmusson have entered into a Consulting 
Agreement as of the 1st day of November, 1995;

     WHEREAS, the Consulting Agreement was drafted with the intent that it 
would commence upon the termination of Rasmusson's Employment Agreement with 
the Company on March 31, 1998;

     WHEREAS, Rasmusson and the Company negotiated an agreement which 
extended the term of  Rasmusson's Employment Agreement for an additional 
eighteen months through September 30, 1999; Rasmusson and the Company 
recently negotiated an agreement which now reduces the term of said 
Employment Agreement to September 1, 1998;

     WHEREAS, as a condition and in consideration of Rasmusson's agreeing to 
reduce the term of his Employment Agreement, the Company has agreed to amend 
the terms of the Consulting Agreement as set forth below.

                                TERMS AND CONDITIONS
                                          
     NOW, THEREFORE, in consideration of the mutual promises hereinafter 
contained, the parties hereto agree as follows:

                             I.    CONSULTING SERVICES

     Section 1 of the Consulting Agreement, entitled "Consulting Services", 
is hereby superseded and replaced by the following new Section 1:

          1.   CONSULTING SERVICES.  Consultant agrees that commencing on the 
     date of his retirement from his duties as an officer and employee of the 
     Company, he will hold himself available, unless disabled from doing so 
     as a result of illness or other incapacity, to advise and consult from 
     time to time, by telephone or in such other manner and at such place or 
     places as may from time to time be mutually agreeable to Consultant and 
     the Company, with the officers, directors, employees and other 
     representatives of the Company when and to the extent reasonably 
     requested to do so by the Company's officers and/or directors, relative 
     to the business of the Company consistent in scope and concept with 
     Rasmusson's 

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     duties and responsibilities while he was employed by the Company.  Upon 
     such request(s), Consultant shall provide to the Company, through such 
     officers, directors, employees and other representatives, the benefit of 
     his experience and knowledge of the business and of his judgment on or 
     with respect to matters, issues and/or subjects submitted to Consultant 
     through such requests. Rasmusson may, but shall not be required to, 
     provide such consulting services in person at the Company's offices.
                                          
                               II.    COMMENCEMENT

     Section 3 of the Consulting Agreement, entitled "Commencement",  is hereby
superseded and replaced by the following new Section 3:

          3.   COMMENCEMENT.  This Agreement shall commence upon termination 
     of the Employment Agreement, as amended.  
     
                                          
                                   III.    FEES

     The first paragraph under Section 4 of the Consulting Agreement, entitled
"Compensation", is hereby superseded and replaced by the following paragraph:

          4.   FEES.  In consideration of the services to be rendered by
     Consultant pursuant to this Agreement during the twenty-four (24)
     month term hereof, the Company shall pay the Consultant the sum of
     Four Hundred Eighty-Five Thousand and No/100 ($485,000.00) Dollars in
     twenty-four (24) equal monthly installment payments in the amount of
     Twenty Thousand Two Hundred Eight and 33/100 ($20,208.33) Dollars
     each, whether or not the Company requests Consultant to provide such
     services.  Payments shall commence in September, 1998 and shall be
     made on the first day in September, 1998 and on the first day of each
     month thereafter through August, 2000.
     
                                          
                                 IV.    TERMINATION

     Section 9 of the Consulting Agreement, entitled "Termination", is hereby
superseded and replaced by the following:

     9.   TERMINATION.  This Agreement shall be terminated upon the second
          anniversary of this Agreement or may otherwise be terminated:
     
          (a)  by Consultant without cause, for any reason or for no reason, 
               at any time upon thirty (30) days written notice to the 
               Company; or
     
          (b)  if Company is in default hereunder and such default is not 
               cured within thirty (30) days of written notice thereof, then 
               Consultant can terminate this Agreement and the non-compete 
               provision hereof is of no further force and effect.


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                               V.    LEGAL FEES

     In the event either party commences legal action to enforce the terms of 
the Consulting Agreement, as amended, the prevailing party in such action 
shall be reimbursed by the non-prevailing party all legal costs and expenses 
and attorney's fees incurred by the prevailing party in such action.

     All other terms of the Consulting Agreement shall remain unchanged, 
subject to future amendment by written agreement of the parties hereto.


COMPANY:                               RASMUSSON:

OXBORO MEDICAL 
INTERNATIONAL, INC.                    /s/ Larry A. Rasmusson  
                                       -----------------------------
                                       Larry A. Rasmusson

By /s/ Robert S. Garin 
   -----------------------------
   Its  Chairman of the Board
        ------------------------


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