Document:

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                                                                   Exhibit 10.38

                              AMENDMENT NO. 1 TO
                             EMPLOYMENT AGREEMENT
                         Dated as of November 11, 1999

     THIS AMENDMENT NO. 1 TO EMPLOYMENT AGREEMENT (this "Agreement") is entered
into this 6th day of March, 2001 (the "Effective Date") between Data Critical
Corporation ("Data Critical" or the "Company") and Robert A. May ("you" or the
"Executive").

                                  WITNESSETH:
                                  ----------

     WHEREAS, the Company and the Executive have entered into a certain letter
agreement dated as of November 11, 1999 (the "Original Employment Agreement")
setting forth certain agreements with respect to terms of the Executive's
employment with the Company; and

     WHEREAS, 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.  The Original Employment Agreement is hereby amended as set
forth in this Section 1:

     1.1  References in the Original Employment Agreement to the dollar
amounts of "$10,416.67" and "$125.000" in respect of Executive's monthly and
annual salary shall be deleted and the amounts "$13,541.67" and "$162,500" shall
be substituted therefor, respectively;

     1.2  The following bulletpoint paragraph shall be added to the second
paragraph of the Original Employment Agreement as an additional component of
Executive's compensation:

          ". You may be entitled to a one-time performance based bonus on the
          terms and conditions set forth on Exhibit A hereto.";

     1.3  The sixth paragraph of the Original Employment Agreement (setting
forth the severance provisions and for cause termination provisions) is hereby
deleted in its entirety and the following shall be inserted in its place:

          "The term of this Agreement shall be extended and shall continue for a
          term of one (1) year from the date hereof, subject to earlier
          termination as set forth below (the "Original Term").  The Company and
          you acknowledge that your employment is and shall continue to be at-
          will, as defined under applicable law, and that your employment with
          the Company may be terminated by either party at any time for any or
          no reason, subject to the terms of this letter agreement.  If your
          employment terminates fox any reason, you shall not be entitled to any
          payments, benefits, damages, award or compensation other than as
          provided in this letter agreement or as otherwise required by law.
          Any payments, benefits, damages, awards, or
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          other compensation provided for hereunder upon any termination hereof
          shall be inclusive of (and not additive to) any such amounts required
          pursuant to any applicable law. The rights and duties created by this
          agreement may not be modified in any way except by a written agreement
          executed by the Company and the you. The terms of this paragraph shall
          survive the termination of this Agreement and/or the termination of
          your employment with the Company.

          In the event that the Company terminates you at any point in time
          without Cause (as defined below) at any time during the Original Tern
          of this Agreement, Data Critical will continue to pay your monthly
          salary $13,541.67 per month (subject to customary withholding) for a
          period of six months after such termination in accordance with its
          standard payroll procedures.  For purposes of this agreement, "Cause"
          shall mean, the commission of an act of fraud or dishonesty in the
          course of your employment with Data Critical; conviction or plea of
          nolo contendre of or to a crime constituting a felony or in respect of
          any act of fraud, dishonesty or moral turpitude; failure to perform
          the duties assigned to you material to the business conduct of Data
          Critical under circumstances in which you knew or should have
          reasonably known that such failure would be detrimental to Data
          Critical, unless you remedy such failure not later than 30 days
          following delivery to you of a written notice from Data Critical
          describing such failure in reasonable detail.  You may also be
          entitled to payment of severance in the amount, at the times and upon
          the conditions set forth on Exhibit A attached hereto.

          You hereby agrees that you shall not, during the term of your
          employment and for a period of 90 days after termination of your
          employment with the Company and/or any of its affiliates for any
          reason, do any of the following without die prior written consent of
          the Board of Directors of the Company (for purposes of this paragraph,
          the term "Company" shall mean the Company and each of its
          subsidiaries):

               (i)   Compete.  Carry on any business or activity (whether
               directly or indirectly, as a partner, stockholder, principal,
               agent, director, affiliate, employee, advisor or consultant) for
               any company or other enterprise carrying on or proposing to carry
               on any business or having any product line related to the
               business of the Company, including, without limitation, in-
               hospital wireless products or systems; enterprise monitoring or
               telemetry products; handheld communications products for doctors,
               nurses and other health care professionals; remote monitoring of,
               or transmission of, ECGs or other patient medical information;
               any pacemaker, arrhythmia follow-up or patient charting software
               or hardware products or technology for cardiologists or cardiac
               surgeons; wireless physician charting products; or any other
               current or currently planned (at the time of your termination)
               products or businesses by the Company, or that are otherwise
               competitive with the business conducted by or planned to be
               conducted by the Company, nor

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               engage in any other activities that conflict with your
               obligations to the Company (any such company or enterprise, being
               a "Competitor").

               (ii)  Solicit Business.  Solicit or influence or attempt to
               influence any client, customer or other person either directly or
               indirectly, to direct his or its purchase of the Company's
               products and/or services to any Competitor.

               (iii) No-Hire.  Solicit or influence or attempt to influence,
               directly or indirectly, any person employed by the Company or any
               of its affiliates to terminate or otherwise cease his employment
               with the Company or hire any such person within 6 months after
               such person's leaving the Company's employ.

               (iv)  Equitable Remedies Survival.  You acknowledge and agree
               that your breach of this Agreement will cause irreparable injury
               to the Company for which money damages and other remedies at law
               would be inadequate, and as such that the Company and/or its
               affiliates shall be entitled to equitable remedies, including,
               without limitation, specific performance and/or temporary or
               permanent injunctive relief. The provisions of clauses (i)-(v) of
               this paragraph shall survive the termination of this Agreement
               and/or the termination of your employment with the Company.

               (v)   Scope.  You acknowledge and agree that the Company has
               relied and is relying on the covenants contained herein in their
               decision to enter into this Agreement and that in light of such
               reliance the covenants contained herein are fair and reasonable.

          Any dispute or claim arising out of or in connection with this
          agreement will be finally settled by binding arbitration in Seattle,
          Washington in accordance with the rules of the American Arbitration
          Association by one arbitrator appointed in accordance with said rules.
          Judgment on the award tendered by the arbitrator may be entered in any
          court having jurisdiction thereof.  Notwithstanding the foregoing, the
          parties may apply to any court of competent jurisdiction for
          preliminary or interim equitable relief, or to compel arbitration in
          accordance with this paragraph, without breach of this arbitration
          provision.  The provisions of this paragraph shall survive the
          termination of this Agreement and/or the termination of your
          employment with the Company.

     1.5. The Original Employment Agreement is hereby further amended to add
Exhibit A attached hereto as Exhibit A thereto.

     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 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 other agreement or
document, and all references in the Employment Agreement to "this Agreement,"

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"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 Agreement shall be governed by the laws of the State of
Washington, without giving effect to the principles of conflict of laws.

     3.2  Severability.  If one or more provisions of the Employment Agreement
are held to be unenforceable under applicable law, the parties agree to
renegotiate such provision in good faith. In the event that the parties cannot
reach a mutually agreeable and enforceable replacement for such provision, then
(i) such provision shall be excluded from the Employment Agreement, (ii) the
balance of the Employment Agreement shall be interpreted as if such provision
were so excluded and (iii) the balance of the Employment Agreement shall be
enforceable in accordance with its terms.

     3.3  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.

     3.4  Advice of Counsel.  EACH PARTY TO THE EMPLOYMENT AGREEMENT AND THIS
AMENDMENT ACKNOWLEDGES THAT, IN EXECUTING THIS AGREEMENT, 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 SUCH AGREEMENTS.  NEITHER THE
EMPLOYMENT AGREEMENT NOR THIS AMENDMENT SHALL BE CONSTRUED AGAINST ANY PARTY BY
REASON OF THE DRAFTING OR PREPARATION HEREOF.

                           [Signature Page Follows]

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     The parties have executed this Agreement the date first written above.

                                  DATA CRITICAL CORPORATION:

                                  By:     /s/ Michael E. Singer
                                     -------------------------------------

                                  Title:   EVP, CFO
                                        ----------------------------------

                                  19820 North Creek Parkway
                                  Suite 100
                                  Bothell, WA  98011

                                  ROBERT A. MAY:

                                  Signature:  /s/ Robert A. May  3/16/01
                                            ------------------------------

                                  18047 NE 99th Court
                                  Redmond, WA  98052

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                                   EXHIBIT A
                                   ---------

Terms of Performance Based Bonus:
--------------------------------

You will be entitled to payment of a one tune cash bonus in the amount of
$50,000 (subject to customary withholding) in the event (and solely in the
event) that and upon (i) the Company consummates the proposed acquisition as
contemplated by Project Viper currently underway and (ii) following such
acquisition, completion under your oversight of the migration and integration of
all in-hospital product manufacturing operations of the Company and the Target
to a single location as designated by the Board of Directors of the Company.

Terms of Severance:
------------------

You shall also be entitled to payment of severance in the amount and on the
terms set forth in Section 4 of the Agreement if, as a requirement of your
continued employment with the Company, the Company has required you to
permanently relocate to Tustin, California and, rather than relocate, you elect
to voluntarily terminate your employment with the Company.

                                       6<PAGE>

                                                                   Exhibit 10.39

                           Data Critical Corporation
                     19820 North Creek Parkway, Suite 100
                               Bothell, WA 98011

                                 March 8, 2001

Jeffrey S. Brown
c/o Data Critical Corporation
19820 North Creek Parkway, Suite 100
Bothell, WA 98011

Dear Jeff:

     It is my pleasure to offer you the following terms and conditions in
consideration of your continued service as a member of the Board of Directors
(the "Board") of Data Critical Corporation (the "Company").  References to "you"
and "Director" mean Jeffrey S. Brown.

     1.  Position.  You shall remain a member of the Board and shall serve out
your current term until its expiration in 2003.  You shall also be appointed as
Chairman of the Board subject to Provision 4.

     2.  Compensation and Benefits.  As Director, you will not receive any
salary or be eligible for any Company benefits (other than those benefits, if
any, granted to members of the Board generally from time to time).  Your
compensation shall consist solely of the following:

     So long as you are Chairman, you shall receive annually twice the standard
     amount of options to purchase shares of the Company's common stock normally
     granted to members of the Board (the "Options").  The Options shall be
     granted on the standard terms and conditions applicable to members of the
     Board generally, except that the Options will vest immediately.

     3.  Term.  This letter agreement shall commence on the date of this letter
and shall terminate on the date on which your current term as Director expires
or otherwise terminates.

     4.  Resignation.  You agree that, notwithstanding the foregoing, promptly
upon the request of a majority of the other members of the Board, you will
voluntarily resign as Chairman and/or from the Board itself.

     5.  Noncompetition Covenant.  You hereby agrees that you shall not, during
your term as Director and for a period of one year after the date on which your
current term as Director expires or otherwise terminates for any reason, do any
of the following without the prior written consent of the Board (for purposes of
this Section, the term "Company" shall mean the Company and each of its
subsidiaries):

     (a) Compete.  Carry on any business or activity (whether directly or
indirectly, as a partner, stockholder, principal, agent, director, affiliate,
employee, advisor or consultant) for any company or other enterprise carrying on
or proposing to carry on any business or having any product line related
<PAGE>

to the business of the Company, including, without limitation, handheld devices
for the medical industry, remote monitoring of, or transmission of, ECGs or
other patient medical information, any pacemaker software or hardware products
or technology, cardiology-related software, physician charting products,
electronic charge capture (or any devices relating thereto) or any current or
currently planned (at the time of Director's termination) products or businesses
by the Company, or that are otherwise competitive with the business conducted by
or planned to conducted by the Company, nor engage in any other activities that
conflict with Director's obligations to the Company (any such company or
enterprise, being a "Competitor").

     (b) Solicit Business.  Solicit or influence or attempt to influence any
client, customer or other person either directly or indirectly, to direct his or
its purchase of the Company's products and/or services to any Competitor.

     (c) No-Hire.  Solicit or influence or attempt to influence, directly or
indirectly, any person employed by the Company or any of its affiliates to
terminate or otherwise cease his employment with the Company or hire any such
person within 6 months after such person's leaving the Company's employ.

     (d) Equitable Remedies. Director acknowledges and agrees that Director's
breach of this letter agreement will cause irreparable injury to the Company for
which money damages and other remedies at law would  be inadequate, and as such
that the Company and/or its affiliates shall be entitled to equitable remedies,
including, without limitation, specific performance and/or temporary or
permanent injunctive relief.

     (e) Scope.  Director acknowledges and agrees that the Company has relied
and is relying on the covenants contained herein in their decision to enter into
this letter agreement and that in light of such reliance the covenants contained
herein are fair and reasonable.

     6.  Effect on other Agreements.  Director acknowledges and agrees that all
other agreements executed by Director with or on behalf of the Company,
including without limitation, any confidentiality agreement and any assignment
of inventions agreement, shall remain in full force and effect without
modification; provided, however that in the event (and solely to the extent) the
terms of this letter agreement and any other such agreement conflict, the terms
of this letter agreement shall be deemed to govern.

     7.  Miscellaneous Provisions.

     (a) Amendments and Waivers.  The terms of this letter agreement may only
be amended or waived only with the written consent of the parties.

     (b) Sole Agreement.  Subject to Section 6 above, this letter agreement,
including any Exhibits hereto, constitutes the sole agreement of the parties and
supersedes all oral negotiations and prior writings with respect to the subject
matter hereof.

     (c) Notices.  Any notice required or permitted by this letter agreement
shall be in writing and shall be deemed sufficient upon receipt, when delivered
personally or by a nationally-recognized delivery service (such as Federal
Express or UPS), or 48 hours after being deposited in the U.S. mail

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as certified or registered mail with postage prepaid, if such notice is
addressed to the party to be notified at such party's address as set forth below
or as subsequently modified by written notice.

     (d) Choice of Law.  The validity, interpretation, construction and
performance of this letter agreement shall be governed by the laws of the State
of Washington, without giving effect to the principles of conflict of laws.

     (e) Severability.  If one or more provisions of this letter agreement are
held to be unenforceable under applicable law, the parties agree to renegotiate
such provision in good faith.  In the event that the parties cannot reach a
mutually agreeable and enforceable replacement for such provision, then (i) such
provision shall be excluded from this letter agreement, (ii) the balance of the
Agreement shall be interpreted as if such provision were so excluded and (iii)
the balance of the Agreement shall be enforceable in accordance with its terms.

     (f) Counterparts.  This letter agreement 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.

     (g) Arbitration.  Any dispute or claim arising out of or in connection
with this letter agreement will be finally settled by binding arbitration in
Seattle, Washington in accordance with the rules of the American Arbitration
Association by one arbitrator appointed in accordance with said rules. Judgment
on the award rendered by the arbitrator may be entered in any court having
jurisdiction thereof.  Notwithstanding the foregoing, the parties may apply to
any court of competent jurisdiction for preliminary or interim equitable relief,
or to compel arbitration in accordance with this paragraph, without breach of
this arbitration provision.

     (h) Survival.  The provision of Sections 4, 5 and 6(g) shall survive both
the termination of this letter agreement and/or the termination of the
Executive's employment with the Company and/or its affiliates.

     (i) Advice of Counsel.  EACH PARTY TO THIS LETTER AGREEMENT ACKNOWLEDGES
THAT, IN EXECUTING THIS LETTER AGREEMENT, 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 LETTER AGREEMENT.  THIS LETTER AGREEMENT SHALL
NOT BE CONSTRUED AGAINST ANY PARTY BY REASON OF THE DRAFTING OR PREPARATION
HEREOF.

                            [Signature Page Follows]

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     The parties have executed this letter agreement the date first written
above.

                                    DATA CRITICAL CORPORATION:

                                    By:  /s/ Michael E. Singer
                                       ----------------------------------

                                    Title:  EVP, CFO
                                          -------------------------------

                                    19820 North Creek Parkway
                                    Suite 100
                                    Bothell, WA  98011

                                    DATA CRITICAL CORPORATION:
                                    COMPENSATION COMMITTEE:

                                    By:
                                       ----------------------------------

                                    Title:
                                          -------------------------------

                                    19820 North Creek Parkway
                                    Suite 100
                                    Bothell, WA  98011

                                    JEFFREY S. BROWN

                                    Signature:  /s/ Jeffrey S. Brown
                                              ---------------------------

                                    224 Waverly Way
                                    Kirkland, WA 98033

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