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                                                                    Exhibit 10.3

                              AMENDMENT NO. 1 TO
                             EMPLOYMENT AGREEMENT
                           Dated as of June 15, 2001

     THIS AMENDMENT NO. 1 TO EMPLOYMENT AGREEMENT (this "Amendment") is entered
into June 15, 2001 between Data Critical Corporation ("Data Critical" or the
"Company") and Bradley R. Harlow ("you" or the "Executive").

                                  WITNESSETH:

     WHEREAS, the Company and the Executive have entered into a certain letter
agreement dated as of March 7, 2001 (the "Original Employment Agreement")
setting forth certain agreements with respect to terms of the Executive's
employment with the Company; and

     WHEREAS, in connection with the Company's acquisition of VitalCom, Inc. and
as a result of the related consolidation and move of the Company's operations to
Tustin, California, the parties hereto wish to amend the terms of the Original
Employment Agreement as hereinafter set forth (the Original Employment
Agreement, as amended by this Amendment, being collectively, the "Employment
Agreement");

     NOW THEREFORE, in consideration of the mutual premises set forth herein and
for other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto hereby agree as follows:

     SECTION 1.  Amendments.  The Original Employment Agreement is hereby
amended as follows:

          1.1  Section 2 of the Original Employment Agreement is amended by
     deleting the second bulletpoint subparagraph in its entirety and replacing
     the same with the following sentence:

          "Forgiveness of all outstanding principal and accrued and unpaid
          interest on the Promissory Note in the original principal amount of
          forty-three thousand, five hundred thirty-six dollars and sixty-two
          cents ($43,536.62), dated as of July 18, 1997 and executed by you in
          favor of the Company, such forgiveness to be effective on June 15,
          2001.  You agree that the terms and conditions of the Promissory Note
          set forth in the letter agreement, dated December 8, 2000, between you
          and the Company shall not apply to such forgiveness, and that such
          letter agreement is hereby terminated in its entirety.  The Company
          will not provide you with a gross-up payment for any federal or state
          income taxes payable on such forgiven amounts, and you agree that you
          shall be solely responsible for payment of any income taxes payable on
          such amounts."

          1.2  Section 4 of the Original Employment Agreement is amended as
     follows:

               (a)  The phrase "the Company will continue to pay your monthly
          salary of $15,625 per month" shall be deleted from the first sentence
          thereof and shall be replaced with the phrase "the Company will pay
          you $15,625 per month".
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               (b)  The following sentence shall be inserted at the beginning
          thereof:

                         "The Company shall provide you with no less than ninety
                    (90) days' advance notice of any termination without cause
                    of your employment.  At the end of such notice period, you
                    will take any accrued but unused PTO and vacation and will
                    remain an employee of the Company until all your accrued PTO
                    and vacation time is consumed.  At the end of this
                    PTO/vacation period, your employment by the Company will
                    terminate and the severance payments described below will
                    commence."

               (c)  The phrases "six months" and "six-month" shall be replaced
          with the phrases "three months" and "three-month" at each respective
          appearance therein.

     SECTION 2.  Effect on Original Employment Agreement.  This Amendment amends
the Original Employment Agreement and all terms of this Amendment shall be
deemed incorporated into and made a part of the Original Employment Agreement.
Except as and to the extent specifically modified by the terms of this
Amendment, all terms of the Original Employment Agreement shall remain in full
force and effect. All references to the Employment Agreement in any agreement or
document, and all references in the Employment Agreement to "this Agreement,"
"hereof," "hereunder," or "hereto" or words of similar import shall be deemed to
be references to the Original Employment Agreement as amended hereby.

     SECTION 3.  Miscellaneous Provisions.

     3.1  Choice of Law.  The validity, interpretation, construction and
performance of this Amendment shall be governed by the laws of the State of
Washington, without giving effect to the principles of conflict of laws.

     3.2  Counterparts.  This Amendment may be executed in counterparts, each of
which shall be deemed an original, but all of which together will constitute one
and the same instrument.

     3.3  Advice of Counsel.  EACH PARTY TO THIS AMENDMENT ACKNOWLEDGES THAT, IN
EXECUTING THIS AMENDMENT, SUCH PARTY HAS HAD THE OPPORTUNITY TO SEEK THE ADVICE
OF INDEPENDENT LEGAL COUNSEL, AND HAS READ AND UNDERSTOOD ALL OF THE TERMS AND
PROVISIONS OF THIS AMENDMENT.  NEITHER THE ORIGINAL EMPLOYMENT AGREEMENT NOR
THIS AMENDMENT SHALL BE CONSTRUED AGAINST ANY PARTY BY REASON OF THE DRAFTING OR
PREPARATION HEREOF.

     3.4  Notice of Termination Without Cause.  Executive and the Company
acknowledge and agree that in connection with the Company's acquisition of
VitalCom, Inc. and as a result of the related consolidation and move of the
Company's operations to Tustin, California, the Company provided, and Executive
received, notice of termination without cause of Executive's employment on
Friday, June 15, 2001 and that such notice satisfies any and all obligations of
the Company to deliver such notice under Section 4 of the Employment Agreement.


                            [Signature Page Follows]

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     The parties have executed this Amendment on the date first written above.

                                 DATA CRITICAL CORPORATION


                                  By:      /s/ Michael E. Singer
                                     -----------------------------------
                                  Name:  Michael E. Singer
                                  Title: Executive Vice President, Corporate
                                         Development, Chief Financial Officer


                                 BRADLEY R. HARLOW:


                                 Signature:   /s/ Bradley R. Harlow
                                           -----------------------------
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