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        EXHIBIT 10.1

        SILICON VALLEY BANK

        AMENDMENT TO LOAN AGREEMENT

BORROWER:      VITALCOM INC., A DELAWARE CORPORATION

ADDRESS:       15222 DEL AMO AVENUE
               TUSTIN, CA  92780

DATED AS OF:   AUGUST 6, 1997

THIS AMENDMENT TO LOAN AGREEMENT is entered into between SILICON VALLEY BANK
("Silicon") and the borrower named above (the "Borrower").

The Parties agree to amend the Loan and Security Agreement between them dated
February 26, 1993, as amended by that Amendment to Loan Agreement dated December
21, 1993, as amended by that Amendment to Loan Agreement dated April 27, 1994,
as amended by that Amendment to Loan Agreement dated May 5, 1995, as amended by
that Amendment to Loan Agreement dated May 30, 1995, as amended by that
Amendment to Loan Agreement dated December 27, 1995 (the "December 1995
Amendment"), as amended by that Amendment to Loan Agreement dated August 6,
1996, as amended by that Amendment to Loan Agreement dated September 25, 1996,
and as otherwise amended from time to time (the "Loan Agreement"; terms defined
in the Loan Agreement are used herein as therein defined), as follows, effective
as of the date hereof.

1.    AMENDED FINANCIAL COVENANTS. The section of the Schedule to the Loan
      Agreement entitled "Financial Covenants (Section 4.1)" is amended
      effective as of the date hereof to read as follows:


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"FINANCIAL COVENANTS
(Section 4.1):             Borrower shall comply with all of the following
                           covenants. Compliance shall be determined as of the
                           end of each calendar quarter, except as otherwise
                           specifically provided below:

QUICK ASSET RATIO:         Borrower shall maintain a ratio of "Quick Assets" to
                           current liabilities of not less than 2.00 to 1.

TANGIBLE NET WORTH:        Borrower shall maintain a tangible net worth of not
                           less than $20,000,000.

DEBT TO TANGIBLE
NET WORTH RATIO:           Borrower shall maintain a ratio of total liabilities
                           to tangible net worth of not more than 1.00 to 1.

MINIMUM  CASH COVERAGE     Borrower shall maintain an aggregate total of cash
                           and marketable securities (valued at market value) in
                           an amount at least equal to the product of two times
                           the maximum amount of the Credit Line.

DEFINITIONS:               "Current Assets" and "current liabilities" shall have
                           the meanings ascribed to them in accordance with
                           generally accepted accounting principles. "Tangible
                           net worth" means the excess of total assets over
                           total liabilities, determined in accordance with
                           generally accepted accounting principles, excluding
                           however all assets which would be classified as
                           intangible assets under generally accepted accounting
                           principles, including without limitation goodwill,
                           licenses, patents, trademarks, trade names,
                           copyrights, and franchises. "Quick Assets" means cash
                           on hand or on deposit in banks, readily marketable
                           securities issued by the United States, readily
                           marketable commercial paper rated "A-1" by Standard &
                           Poor's Corporation (or a similar rating by a similar
                           organization), certificates of deposit and banker's
                           acceptances, and accounts receivable (net of
                           allowance for doubtful accounts).

SUBORDINATED DEBT:         "Liabilities" for purposes of the foregoing covenants
                           do not include indebtedness which is subordinated to
                           the indebtedness to Silicon under a subordination
                           agreement in form specified by Silicon or by language
                           in the instrument evidencing the indebtedness which
                           is acceptable to Silicon.

2.    AMENDED MATURITY DATE. The section of the Schedule to the Loan Agreement
      entitled "Maturity Date (Section 5.1)" is amended effective as of the date
      hereof to read as follows:


                "Maturity Date
                (Sections 5.1):             August 5, 1998."

3.    CONSENT TO BORROWER LOANS. Borrower has made (I) a bridge loan to its Vice
      President of Direct Sales in the approximate amount of $175,000 and (II)
      two loans in an aggregate amount of $194,960 to two consultants of
      borrower relating to such persons' purchase of Borrower's stock
      (collectively, the "Borrower Loans"). Silicon hereby consents to the
      Borrower Loans, and hereby agrees that no Event of Default shall arise
      under the Loan Agreement in connection herewith.

4.    FEE. It is acknowledged that Borrower shall pay to Silicon a fee in the
      amount of $8,250 in connection with this Amendment, which shall be in
      addition to all interest and all other fees payable to Silicon and shall
      be non-refundable. At such time that any Loans are made hereunder,
      Borrower shall, prior to Silicon's making of any such 


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      Loans, pay to Silicon a further fee of $8,250, which shall be in addition
      to all interest and all other fees payable to Silicon and shall be
      non-refundable.

5.    GENERAL PROVISIONS. This Amendment, the Loan Agreement, any prior written
      amendments to the Loan Agreement signed by Silicon and the Borrower, and
      the other written documents and agreements between Silicon and the
      Borrower set forth in full all of the representations and agreements of
      the parties with respect to the subject matter hereof and supersede all
      prior discussions, representations, agreements and understandings between
      the parties with respect to the subject hereof. Except as herein expressly
      amended, ,all of the terms and provisions of the Loan Agreement, and all
      other documents and agreements between Silicon and the Borrower shall
      continue in full force and effect and the same are hereby ratified and
      confirmed. This Amendment shall be controlling in the event of any
      conflicts between any prior written agreements and amendments between
      Silicon and the Borrower, on the one hand, and the Amendment.


Borrower:                                Silicon:

VITALCOM INC., a Delaware corporation    SILICON VALLEY BANK


By  /s/Donald W. Judson
-------------------------------------
        President or Vice President

                                         By /s/Kittridge Chamberlain
                                            --------------------------
By/s/ Shelley B. Thunen                  Title  V.P.
  -----------------------------------          -----------------------
        Secretary


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