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                                                                   EXHIBIT 10.24

                                     SUPPLEMENT NO. 1 dated as of May 29, to the
                        Subsidiary Guarantee Agreement dated as of May 14, 2002,
               among each of the subsidiaries listed on Schedule I thereto (each
               such subsidiary individually, a "Guarantor" and collectively, the
               "Guarantors") of HUDSON RESPIRATORY CARE INC., a California
               corporation (the "Borrow"), and DEUTSCHE BANK TRUST COMPANY
               AMERICAS, a New York banking corporation, as collateral agent
               (the "Collateral Agent") for the Secured Parties (as defined in
               the Credit Agreement referred to below).

     A.  Reference is made to the Credit Agreement dated as of April 7,1998 (as
amended, supplemented or otherwise modified from time to time, the "Credit
Agreement"), among the Borrower, the lenders from time to time party thereto
(the "Lenders"), Bankers Trust Company, as administrative agent for the Lenders
(in such capacity, the "Administrative Agent"), Collateral Agent and issuing
bank (in such capacity, the "Issuing Bank").

     B.  Capitalized terms used herein and not otherwise defined herein shall
have the meanings assigned to such terms in the Guarantee Agreement and the
Credit Agreement.

     C.  The Guarantors have entered into the Guarantee Agreement in order to
induce the Lenders to make Loans and the Issuing Bank to issue Letters of
Credit. Pursuant to Section 5.11 of the Credit Agreement, each Subsidiary of the
Borrower that was not in existence or not a Subsidiary on the date of the Credit
Agreement is required to enter into the Guarantee Agreement as a Guarantor upon
becoming a Subsidiary. Section 20 of the Guarantee Agreement provides that
additional Subsidiaries of the Borrower may become Guarantors under the
Guarantee Agreement by execution and delivery of an instrument in the form of
this Supplement. The undersigned Subsidiary of the Borrower (the "New
Guarantor") is executing this Supplement in accordance with the requirements of
the Credit Agreement to become a Guarantor under the Guarantee Agreement in
order to induce the Lenders to make additional Loans and the Issuing Bank to
issue additional Letters of Credit and as consideration for Loans previously
made and Letters of Credit previously issued.

     Accordingly, the Collateral Agent and the New Guarantor agree as follows:

     Section 1.  In accordance with Section 20 of the Guarantee Agreement, the
New Guarantor by its signature below becomes a Guarantor under the Guarantee
Agreement with the same force and effect as if originally named therein as a
Guarantor and the New Guarantor hereby (a) agrees to all the terms and
provisions of the Guarantee Agreement applicable to it as a Guarantor thereunder
and (b) represents and warrants that the representations and warranties made by
it as a Guarantor thereunder are true and correct on and as of the date hereof.
Each reference to a "Guarantor" in the Guarantee Agreement shall be deemed to
include the New Guarantor. The Guarantee Agreement is hereby incorporated herein
by reference.

     Section 2.  This Supplement may be executed in counterparts, each of which
shall constitute an original, but all of which when taken together shall
constitute a single contract.

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This Supplement shall become effective when the Collateral Agent shall have
received counterparts of this Supplement that, when taken together, bear the
signatures of the New Guarantor and the Collateral Agent. Delivery of an
executed signature page to this Supplement by facsimile transmission shall be as
effective as delivery of a manually executed counterpart of this Supplement.

     Section 3.  Except as expressly supplemented hereby, the Guarantee
Agreement shall remain in full force and effect.

     Section 4.  THIS SUPPLEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO PRINCIPLES
OF CONFLICTS OF LAWS.

     Section 5.  In case any one or more of the provisions contained in this
Supplement should be held invalid, illegal or unenforceable in any respect, the
validity, legality and enforceability of the remaining provisions contained
herein and in the Guarantee Agreement shall not in any way be affected or
impaired thereby (it being understood that the invalidity of a particular
provision hereof in a particular jurisdiction shall not in and of itself affect
the validity of such provision in any other jurisdiction). The parties hereto
shall endeavor in good-faith negotiations to replace the invalid, illegal or
unenforceable provisions with valid provisions the economic effect of which
comes as close as possible to that of the invalid, illegal or unenforceable
provisions.

     Section 6.  All communications and notices hereunder shall be in writing
and given as provided in Section 14 of the Guarantee Agreement. All
communications and notices hereunder to the New Guarantor shall be given to it
at the address set forth under its signature below, with a copy to the Borrower.

     Section 7.  The New Guarantor agrees to reimburse the Collateral Agent for
its out-of-pocket expenses in connection with this Supplement, including the
fees, disbursements and other charges of counsel for the Collateral Agent.


                                        2

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     IN WITNESS WHEREOF, the New Guarantor and the Collateral Agent have duly
executed this Supplement to the Guarantee Agreement as of the day and year first
above written.

                                          INDUSTRIAS HUDSON, S.A. de C.V.,

                                            by

                                               ---------------------------------
                                               Name:
                                               Title:
                                               Address:


                                          DEUTSCHE BANK TRUST COMPANY
                                          AMERICAS, as Collateral Agent,

                                            by

                                               ---------------------------------
                                               Name:
                                               Title:


                                       S-1