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                                                                     EXHIBIT 4.3
                         AMENDMENT TO RIGHTS AGREEMENT

1.   General Background.  In accordance with Section 26 of the Rights Agreement
     between First Chicago Trust Company of New York (the "Rights Agent") and
     Spacelabs Medical Inc. dated June 26, 1992 (the "Agreement"), the Rights
     Agent and Spacelabs Medical Inc. desire to amend the Agreement to appoint
     EquiServe Trust Company, N.A.

2.   Effectiveness.  This Amendment shall be effective as of November 2, 2001
     (the "Amendment") and all defined terms and definitions in the Agreement
     shall be the same in the Amendment except as specifically revised by the
     Amendment.

3.   Revision.   The section in the Agreement entitled "Change of Rights Agent"
     is hereby deleted in its entirety and replaced with the following:

     Change of Rights Agent.  The Rights Agent or any successor Rights Agent may
     resign and be discharged from its duties under this Agreement upon 30 days'
     notice in writing mailed to the Company and to each transfer agent of the
     Common Shares or Preferred shares by registered or certified mail and to
     the holders of the Right Certificates by first-class mail.  The Company may
     remove the Rights Agent or any successor Rights Agent upon 30 days' notice
     in writing mailed to the Rights Agent or successor Rights Agent, as the
     case may be, and to each transfer agent of the Common Shares or Preferred
     Shares by registered or certified mail, and to the holders of the Right
     Certificates by first-class mail.  If the Rights Agent shall resign or be
     removed or shall otherwise become incapable of acting, the Company shall
     appoint a successor to the Rights Agent. If the Company shall fail to make
     such appointment within a period of 30 days after giving notice of such
     removal or after it has been notified in writing of such resignation or
     incapacity by the resigning or incapacitated rights Agent or by the holder
     of a Right Certificate (who shall, with such notice, submit such holder's
     Right Certificate for inspection by the company), then the registered
     holder of any Right Certificate may apply to any court of competent
     jurisdiction for the appointment of a new Rights Agent.  Any successor
     Rights Agent, whether appointed by the Company or by such a court, shall be
     a corporation or trust company organized and doing business under the laws
     of the United States, in good standing, which is authorized under such laws
     to exercise corporate trust or stock transfer powers and is subject to
     supervision or examination by federal or state authority and which has
     individually or combined with an affiliate at the time of its appointment
     as Rights Agent a combined capital and surplus of at least $100 million
     dollars.  After appointment, the successor Rights Agent shall be vested
     with the same powers, rights, duties and responsibilities as if it had been
     originally named as Rights Agent without further act or deed; but the
     predecessor Rights Agent shall deliver and transfer to the successor Rights
     Agent any property at the time held by it hereunder, and execute and
     deliver any further assurance, conveyance, act or deed necessary for the
     purpose.  Not later than the effective date of any such appointment the
     Company shall file notice thereof in writing with the predecessor Rights
     Agent and each transfer agent of the Common Shares or Preferred Shares, and
     mail a notice thereof in writing to the registered holders of the Right
     Certificates.  Failure to give any notice provided for in this Section 22,
     however, or any defect therein, shall not affect the legality or validity
     of the resignation or removal of the Rights Agent or the appointment of the
     successor Rights Agent, as the case may be.

4.   Except as amended hereby, the Agreement and all schedules or exhibits
     thereto shall remain in full force and effect.

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed
in their names and on their behalf by and through their duly authorized
officers, as of this 2nd day of November, 2001.


Spacelabs Medical Inc.                      First Chicago Trust Co. of New York


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By:                                         By:
Title:                                      Title: