EXHIBIT 10.13




                  FORM OF AMENDMENT NO. 1 TO CREDIT AGREEMENT

                         This AMENDMENT NO. 1 TO CREDIT AGREEMENT is made and
                    entered into as of July 30, 1998, by and among HUDSON
                    RESPIRATORY CARE INC., a California corporation (the
                    "Borrower"), RIVER HOLDING CORP., a Delaware corporation
                    ("Holding") and the Required Lenders (as defined in Article
                    I of the Credit Agreement).

                                    RECITALS

     A.  The Borrower, Holding, the Lenders (as defined in Article I of the
Credit Agreement), Salomon Brothers Inc, and Bankers Trust Company, entered into
a Credit Agreement dated as of April 7, 1998 (the "Credit Agreement"), pursuant
to which the Borrower made negative covenants concerning its Debt/Adjusted
EBITDA Ratio and its Minimum EBITDA. Capitalized terms used herein and not
otherwise defined shall have the meanings assigned to them in the Credit
Agreement.

     B.  The Borrower requested an amendment to such negative covenants and to
certain definitions.

     C.  The Required Lenders are willing to so amend the Credit Agreement on
the terms and conditions set forth herein.

     D.  The Borrower, Holding and the Required Lenders are entering this
Amendment pursuant to Section 9.08(b) of the Credit Agreement.

                                   AGREEMENTS

     In consideration of the foregoing Recitals, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
Borrower, Holding and the Required Lenders agree as follows:

     1.  Definitions. (a) The following definitions as presented in Article I of
the Credit Agreement are amended in their entirety to read as follows:

          "Consolidated Net Income" means, for any period, the net income (loss)
     of the Borrower and its consolidated Subsidiaries; provided, however, that
     there shall not be included in such Consolidated Net Income (a) any net
     income (loss) of any person (other than the Borrower) if such person is not
     a Restricted Subsidiary, except that (i) subject to the exclusion contained
     in clause (d), the Borrower's equity in the net income of any such person
     for such period shall be included in such Consolidated Net Income up to the
     aggregate amount of cash distributed by such person during such period to
     the Borrower or a Restricted Subsidiary as a dividend or other distribution
     (subject, in the case of a dividend or other distribution to a Restricted
     Subsidiary, to the limitations contained in clause (c)) and (ii) the
     Borrower's equity in a net loss of any such person other than an
     Unrestricted Subsidiary for such period shall be included in determining
     such Consolidated Net Income, (b) for the purposes of Section 6.06 only,
     any net income (loss) of any person acquired by the Borrower or any of its
     consolidated Subsidiaries in a pooling of interests transaction for any
     period prior to the date of such acquisition, (c) any net income (but not
     loss) of any Restricted Subsidiary if such Restricted Subsidiary is subject
     to restrictions, 

 
     directly or indirectly, on the payment of dividends or the making of
     distributions, directly or indirectly, to the Borrower, except that subject
     to the exclusion contained in clause (d), the Borrower's equity in the net
     income of any such Restricted Subsidiary for such period shall be included
     in such Consolidated Net Income up to the aggregate amount of cash
     distributed by such Restricted Subsidiary during such period to the
     Borrower or another Restricted Subsidiary as a dividend or other
     distribution (subject, in the case of a dividend or other distribution to
     another Restricted Subsidiary, to the limitation contained in this clause),
     (d) any gain (but not loss) realized upon the sale or other disposition of
     any Property of the Borrower or any of its consolidated Subsidiaries
     (including pursuant to any Sale and Leaseback Transaction) which is not
     sold or otherwise disposed of in the ordinary course of business; provided,
     that any tax benefit or tax liability resulting therefrom shall be excluded
     in calculating such Consolidated Net Income, (e) any extraordinary gain or
     loss; provided, that any tax benefit or tax liability resulting therefrom
     shall be excluded in calculating such Consolidated Net Income, (f) the
     cumulative effect of a change in accounting principles, (g) any non-cash
     compensation expense realized for grants of performance shares, stock
     options or other stock awards to officers, directors and employees of the
     Borrower or any Restricted Subsidiary, (h) compensation expense realized
     with respect to periods prior to the Closing Date in respect of payments
     under the Borrower's 1994 Amended and Restated Equity Participation Plan,
     (i) Contingent Acquisition-Related Payments; (j) fees and expenses incurred
     in connection with the Recapitalization and referred to in Section 4.02(s)
     to the extent the same would otherwise constitute an expense which would be
     deducted in calculating Consolidated Net Income; (k) compensation expense
     realized with respect to retention bonuses paid in connection with the
     Recapitalization to employees of the Borrower or any Subsidiary in an
     amount not to exceed $4,400,000, to the extent such expense was paid from
     the Redemption Amount, and (l) any expense attributable to taxes incurred
     by the Borrower as a result of its making the election under Section
     338(h)(10) of the Code in connection with the Recapitalization in an amount
     not to exceed $2,800,000.

          "Fixed Charge Coverage Ratio" means, with respect to the Borrower and
     its Restricted Subsidiaries for any period of four consecutive fiscal
     quarters, the ratio of (a) EBITDA for such period, to (b) the sum of
     Capital Expenditures paid in cash, Consolidated Interest Expense, scheduled
     amortizations of Debt, taxes paid or due and payable (excluding taxes paid
     resulting from the Borrower making the election under Section 338(h)(10) of
     the Code in 1998 in connection with the Recapitalization in an amount not
     to exceed $2,800,000), and dividends or other distributions on the Capital
     Stock of such person paid in cash (other than to the Borrower or another
     Restricted Subsidiary), in each case for such period.

     (b) Clause (a) of the definition of "Excess Cash Flow" is amended in its
entirety to read:

          (a) (i) permitted Capital Expenditures, (ii) taxes of the Borrower and
     the Subsidiaries paid or payable in cash for such period, (iii) cash
     consideration paid for Permitted Acquisitions (but excluding cash
     consideration funded by a Borrowing under the Revolving Credit
     Commitments), (iv) Consolidated Interest Expense, (v) increases in Adjusted
     Working Capital for such period, (vi) scheduled and mandatory payments of
     Debt, (vii) payments pursuant to Section 6.05(a)(i)(A) in connection with
     purchases of Excluded Shares, (viii) Contingent Acquisition-Related
     Payments, (ix) compensation payments made in such period in respect of
     amounts excluded from the definition of "Consolidated Net Income" by virtue
     of clause (h) thereof, and (x) dividends paid with respect to the
     Borrower's Exchangeable Preferred Stock to the extent permitted by Section
     6.05(a)(ii), in each case to the extent made in cash during such period;

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     2.  Debt/Adjusted EBITDA Ratio. Section 6.09 of the Credit Agreement is
amended in its entirety to read as follows:

          Section 6.09.  Debt/Adjusted EBITDA Ratio.  The Debt/Adjusted EBITDA
Ratio shall not exceed the following amounts as of the ends of fiscal quarters
of the Borrower ending nearest to the following dates:



  FISCAL QUARTER                                DEBT/ADJUSTED EBITDA RATIO
 ENDING NEAREST
 TO
- ------------------------------------------------------------------------------------------------------
                                                                        
                          1998        1999        2000        2001        2002        2003        2004
- ------------------------------------------------------------------------------------------------------
March 31                         6.00:1.00   5.25:1.00   4.50:1.00   3.75:1.00   3.50:1.00   3.50:1.00
- ------------------------------------------------------------------------------------------------------
June 30              6.75:1:00   6.00:1.00   5.00:1.00   4.25:1.00   3.75:1.00   3.50:1.00
- ------------------------------------------------------------------------------------------------------
September 30         6.75:1:00   6.00:1.00   5.00:1.00   4.25:1.00   3.75:1.00   3.50:1.00
- ------------------------------------------------------------------------------------------------------
December 31          6.00:1.00   5.25:1.00   4.50:1.00   3.75:1.00   3.50:1.00   3.50:1.00
- ------------------------------------------------------------------------------------------------------


          and thereafter, 3.50:1.00.

     3.  Minimum EBITDA.  Section 6.10 of the Credit Agreement is amended in its
entirety to read as follows:

          Minimum EBITDA.  The EBITDA for the fiscal year of the Borrower shall
          not be less than the following amounts as of the end of the following
          fiscal years:


                           
          FISCAL YEAR ENDING                             
             NEAREST TO                                  
            DECEMBER 31,            MINIMUM EBITDA       
          ------------------      -----------------      
                                                   
                1998                 $26,500,000         
                1999                 $29,000,000         
                2000                 $32,000,000         
                2001                 $34,000,000         
                2002                 $37,000,000         
                2003                 $39,000,000         
          and thereafter                                  


     4.  Binding Effect.  This Amendment may be executed in as many counterparts
as may be convenient and shall become binding when the Borrower, Holding and the
Required Lenders have each executed and delivered at least one counterpart.

     5.  Governing Law.  This Amendment shall be a contract made under and
governed by the laws of the State of New York, without regard to the conflicts
of law provisions thereof.

     6.  Reference to Credit Agreement.  Except as amended hereby, the Credit
Agreement shall remain in full force and effect and is hereby ratified and
confirmed in all respects.  On and after the effectiveness of the amendment to
the Credit Agreement accomplished hereby, each reference in the Credit
Agreement, to "this Agreement", "hereunder", "hereof", "herein" or words 

                                       3

 
of like import, and each reference to the Credit Agreement shall be deemed a
reference to the Credit Agreement, as amended hereby, as the case may be. 

                                       4

 
IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed by their respective officers as of the date first above written.


                              HUDSON RESPIRATORY CARE INC.,

                                by  __________________________________

                                     Name:
                                     Title:


                              RIVER HOLDING CORP.,

                                by  __________________________________

                                     Name:
                                     Title:


                              Acknowledged by:

                              BANKERS TRUST COMPANY, as Administrative Agent,
                              Collateral Agent, Swingline Lender and Issuing
                              Bank,

                                by  __________________________________

                                     Name:
                                     Title:


                              SALOMON BROTHERS INC, as Arranger, Advisor and
                              Syndication Agent,

                                by  __________________________________

                                     Name:
                                     Title:

                                       5

 
                                        LENDERS
                                        -------

                              BANKERS TRUST COMPANY,

                                by  __________________________________

                                     Name:
                                     Title:


                              SALOMON BROTHERS HOLDING COMPANY INC,

                                by  __________________________________

                                     Name:
                                     Title:


                              BANK OF AMERICA NATIONAL TRUST AND SAVINGS
                              ASSOCIATION,

                                by  __________________________________

                                     Name:
                                     Title:


                                by  __________________________________

                                     Name:
                                     Title:


                              BANK OF TOKYO-MITSUBISHI TRUST COMPANY,

                                by  __________________________________

                                     Name:
                                     Title:

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                              BHF-BANK AKTIENGESELLSCHAFT,

                                by  __________________________________

                                     Name:
                                     Title:


                                by  __________________________________

                                     Name:
                                     Title:


                              CREDITANSTALT CORPORATE FINANCE, INC,

                                by  __________________________________

                                     Name:
                                     Title:


                                by  __________________________________

                                     Name:
                                     Title:


                              WELLS FARGO BANK, N.A.,

                                by  __________________________________

                                     Name:
                                     Title:


                              ROYAL BANK OF CANADA,

                                by  __________________________________

                                     Name:
                                     Title:


                              NATIONSBANK, N.A., as successor to NationsBank of
                              Texas, N.A.,

                                by  __________________________________

                                     Name:
                                     Title:

                                       7

 
                              SOCIETE GENERALE,

                                by  __________________________________

                                     Name:
                                     Title:


                              IMPERIAL BANK,

                                by  __________________________________

                                     Name:
                                     Title:

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