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                                                                   EXHIBIT 10.11

SILICON VALLEY BANK

                           AMENDMENT TO LOAN AGREEMENT

BORROWER:             I-FLOW CORPORATION
ADDRESS:              20202 WINDROW DRIVE
                      LAKE FOREST, CALIFORNIA  92630

DATED:                MARCH 2, 1998


        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 Silicon and I-Flow
Corporation, dated September 28, 1995, as amended by that Amendment to Loan
Agreement dated July __, 1996 (pursuant to which I-Flow Acquisition Subsidiary
was acquired and made a Borrower under the Loan Agreement), as amended by that
Amendment to Loan Agreement dated April 4, 1997 and as amended by that Amendment
to Loan Agreement dated August 19, 1997 (as so amended and as otherwise amended
from time to time, the "Loan Agreement"), as follows, effective as of the date
hereof. (Capitalized terms used but not defined in this Amendment, shall have
the meanings set forth in the Loan Agreement.)

        I-Flow Acquisition Subsidiary was previously an additional Borrower
under the Loan Agreement. I-Flow Acquisition Subsidiary changed its name to
Block Medical, Inc. and recently merged with and into I-Flow Corporation, with
I-Flow Corporation as the surviving entity. Therefore I-Flow Corporation is the
sole Borrower under the Loan Agreement.

        1. MODIFIED CREDIT LIMIT. Section 1.1 (Credit Limit) of the Schedule to
Loan Agreement is hereby amended to read as follows:

                                 "(I) Revolving Loans. An amount (the "Revolving
                                 Loans") not to exceed the lesser of: (i)
                                 $4,000,000 at any one time outstanding; or (ii)
                                 75% (the "Advance Percentage") of the Net
                                 Amount of Borrower's accounts, which Silicon in
                                 its discretion deems eligible for borrowing,
                                 provided that with respect to Approved Foreign
                                 Accounts the Advance Percentage is "35%". "Net
                                 Amount" of an account means the gross amount of
                                 the account, minus all applicable sales, use,
                                 excise and other similar taxes and minus all
                                 discounts, credits and allowances of any nature
                                 granted or claimed.

                                 Without limiting the fact that the
                                 determination of which accounts are eligible
                                 for borrowing is a matter of Silicon's
                                 discretion, the following will not be deemed
                                 eligible for borrowing: accounts outstanding
                                 for more than 90 days from the invoice date,
                                 accounts subject to any contingencies, accounts
                                 owing from the United States or any department,
                                 agency or instrumentality of the United States
                                 or any state, city or municipality, accounts
                                 owing from an account debtor 

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                      SILICON VALLEY BANK            AMENDMENT TO LOAN AGREEMENT
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                                 outside the United States (unless pre-approved
                                 by Silicon in its discretion, or backed by a
                                 letter of credit satisfactory to Silicon, or
                                 FCIA insured satisfactory to Silicon*),
                                 accounts owing from one account debtor to the
                                 extent they exceed 25% of the total eligible
                                 accounts outstanding, accounts owing from an
                                 affiliate of Borrower, and accounts owing from
                                 an account debtor to whom Borrower is or may be
                                 liable for goods purchased from such account
                                 debtor or otherwise. In addition, if more than
                                 50% of the accounts owing from an account
                                 debtor are outstanding more than 90 days from
                                 the invoice date or are otherwise not eligible
                                 accounts, then all accounts owing from that
                                 account debtor will be deemed ineligible for
                                 borrowing.

                                 * , WITH FRESENIUS MEDICAL CARE A.G. AND
                                 INPHARDIAL ZAMBON BIOMEDICA (AND THE ACCOUNTS
                                 RELATING TO SUCH ACCOUNT DEBTORS ARE REFERRED
                                 TO HEREIN AS THE "APPROVED FOREIGN ACCOUNTS")
                                 AS SUCH PREAPPROVED ACCOUNT DEBTORS PROVIDED
                                 THAT THE RELATED ACCOUNTS ARE OTHERWISE DEEMED
                                 ELIGIBLE HEREUNDER

                                 PLUS

                                 II.  Term  Loan A.

                                 The amount of $4,000,000 (such Loan is "Term
                                 Loan A" and the loan facility relating thereto
                                 is the "Term Loan A Facility") which was
                                 utilized by the Borrower for the purpose of
                                 financing a portion of the purchase of the
                                 assets of Block Medical, Inc. Such acquisition
                                 and related transactions contemplated thereby
                                 are collectively referred to as the
                                 "Acquisition".

                                 Once amounts under the Term Loan A Facility are
                                 repaid, such amounts may not be reborrowed.

                                 Borrower hereby further promises to pay
                                 interest to Silicon on the unpaid principal
                                 balance of Term Loan A at the interest rate as
                                 set forth below. Such interest shall be paid
                                 each month in accordance with the terms of the
                                 Loan Agreement.

                                 Borrower shall repay to Silicon the outstanding
                                 aggregate principal amount of Term Loan A in 48
                                 consecutive equal monthly installments on the
                                 first day of each month, commencing August 1,
                                 1996. The first 47 installments shall be in the
                                 amount of $83,333.34, and the final installment
                                 shall be in remaining principal amount of the
                                 Term Loan.

                                 PLUS

                                 III.  Term Loan B.

                                 The amount of $2,500,000 (such Loan is "Term
                                 Loan B" and the loan facility relating thereto
                                 is the "Term Loan B Facility") 


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                                 to be utilized by the Borrower in a single
                                 utilization on or about March ___, 1998.

                                 Once amounts under the Term Loan B Facility are
                                 repaid, such amounts may not be reborrowed.

                                 Borrower hereby further promises to pay
                                 interest to Silicon on the unpaid principal
                                 balance of Term Loan B at the interest rate as
                                 set forth below. Such interest shall be paid
                                 each month in accordance with the terms of the
                                 Loan Agreement. Borrower shall repay to Silicon
                                 the outstanding aggregate principal amount of
                                 Term Loan B in 54 consecutive equal monthly
                                 installments on the first day of each month,
                                 commencing October 1, 1998. The first 53
                                 installments shall be in the amount of
                                 $46,296.30, and the final installment shall be
                                 in remaining principal amount of the Term Loan
                                 B.



    LETTER OF CREDIT SUBLIMIT    Silicon, in its reasonable discretion, will
                                 from time to time during the term of this
                                 Agreement issue letters of credit for the
                                 account of the Borrower ("Letters of Credit"),
                                 in an aggregate amount at any one time
                                 outstanding not to exceed $500,000, upon the
                                 request of the Borrower, provided that, on the
                                 date the Letters of Credit are to be issued,
                                 Borrower has available to it Revolving Loans in
                                 an amount equal to or greater than the face
                                 amount of the Letters of Credit to be issued.
                                 Prior to the issuance of any Letters of Credit,
                                 Borrower shall execute and deliver to Silicon
                                 Applications for Letters of Credit and such
                                 other documentation as Silicon shall specify
                                 (the "Letter of Credit Documentation"). Fees
                                 for the Letters of Credit shall be as provided
                                 in the Letter of Credit Documentation. Letters
                                 of Credit may have a maturity date up to twelve
                                 months beyond the Maturity Date in effect from
                                 time to time, provided that if on the Maturity
                                 Date, or on any earlier effective date of
                                 termination, there are any outstanding letters
                                 of credit issued by Silicon or issued by
                                 another institution based upon an application,
                                 guarantee, indemnity or similar agreement on
                                 the part of Silicon, then on such date Borrower
                                 shall provide to Silicon cash collateral in an
                                 amount equal to the face amount of all such
                                 letters of credit plus all interest, fees and
                                 costs due or to become due in connection
                                 therewith, to secure all of the Obligations
                                 relating to said letters of credit, pursuant to
                                 Silicon's then standard form cash pledge
                                 agreement.

                                 The Credit Limit set forth above regarding
                                 Revolving Loans and the Revolving Loans
                                 available under this Agreement at any time
                                 shall be reduced by the face amount of Letters
                                 of Credit from time to time outstanding.


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        2. MODIFIED INTEREST RATE. Section 1.2 of the Schedule to Loan Agreement
regarding the Interest Rate is hereby amended to read as follows:

    INTEREST RATE (Section 1.2): Revolving Loans: With respect to Revolving
                                 Loans and all related Obligations the interest
                                 rate shall be a rate equal to the "Prime Rate"
                                 in effect from time to time, plus .75% per
                                 annum. Interest shall be calculated on the
                                 basis of a 360-day year for the actual number
                                 of days elapsed. "Prime Rate" means the rate
                                 announced from time to time by Silicon as its
                                 "prime rate;" it is a base rate upon which
                                 other rates charged by Silicon are based, and
                                 it is not necessarily the best rate available
                                 at Silicon. The interest rate applicable to the
                                 Obligations shall change on each date there is
                                 a change in the Prime Rate.

                                 Term Loan A:

                                 With respect to Term Loan A and all related
                                 Obligations, the interest rate shall be a rate
                                 equal to the "Prime Rate" in effect from time
                                 to time, plus 1.00% per annum. Interest shall
                                 be calculated on the basis of a 360-day year
                                 for the actual number of days elapsed. "Prime
                                 Rate" means the rate announced from time to
                                 time by Silicon as its "prime rate;" it is a
                                 base rate upon which other rates charged by
                                 Silicon are based, and it is not necessarily
                                 the best rate available at Silicon. The
                                 interest rate applicable to the Obligations
                                 shall change on each date there is a change in
                                 the Prime Rate.

                                 Term Loan B:

                                 With respect to Term Loan B and all related
                                 Obligations, the interest rate shall be a rate
                                 equal to the "Prime Rate" in effect from time
                                 to time, plus 1.00% per annum. Interest shall
                                 be calculated on the basis of a 360-day year
                                 for the actual number of days elapsed. "Prime
                                 Rate" means the rate announced from time to
                                 time by Silicon as its "prime rate;" it is a
                                 base rate upon which other rates charged by
                                 Silicon are based, and it is not necessarily
                                 the best rate available at Silicon. The
                                 interest rate applicable to the Obligations
                                 shall change on each date there is a change in
                                 the Prime Rate."

        3. MODIFIED MATURITY DATE. Section 5.1 of the Schedule to Loan Agreement
regarding the Maturity Date is hereby amended to read as follows:

     "MATURITY DATE

      (Section 5.1):             FEBRUARY 15, 1999, provided that the Maturity
                                 Date with respect to each of Term Loan A and
                                 Term Loan B shall be as is set forth in Section
                                 1.1 above."

        4. MODIFIED FEE. Section 1.3 of the Schedule to Loan Agreement regarding
the Loan Origination Fee is hereby amended to read as follows:

     "LOAN ORIGINATION FEE

      (Section 1.3):             $12,500 to be paid in full concurrently
                                 herewith; and $20,000 to be paid on an annual
                                 basis in connection herewith, which latter fee
                                 shall be payable by the Borrower in
                                 installments of 


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                                 $5,000 on each of March 31, 1998, June 30,
                                 1998, September 30, 1998, and December 31,
                                 1998. Failure to pay such amount on each of
                                 such dates shall constitute an Event of Default
                                 hereunder. Such fees shall be in addition to
                                 interest and to all other amounts payable
                                 hereunder and shall not be refundable."

        5. FINANCIAL COVENANTS. Section 4.1 of the Schedule to Loan Agreement
regarding the Financial Covenants is hereby amended to read as follows:

    "FINANCIAL COVENANTS

      (Section 4.1):             Borrower, on a consolidated basis, shall comply
                                 with all of the following covenants. Compliance
                                 shall be determined as of the end of each
                                 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
                                 1.00 to 1.

    STATED NET WORTH:            Borrower shall maintain a stated net worth of
                                 not less than $9,000,000.

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

    PROFITABILITY:               Borrower shall not incur a loss (after taxes)
                                 for any fiscal quarter, except that Borrower
                                 may incur a loss (after taxes) for a single
                                 fiscal quarter during the term hereof not to
                                 exceed $100,000. Notwithstanding the foregoing,
                                 Borrower may incur a loss (after taxes) for the
                                 quarter ending December 31, 1997 not to exceed
                                 $1,600,000.

    DEBT SERVICE RATIO:          Borrower shall maintain a Debt Service Ratio
                                 (as referred to below) of not less than 1.50 to
                                 1 as of the end of each fiscal quarter.

    DEFINITIONS:                 "Current assets," and "current liabilities"
                                 shall have the meanings ascribed to them in
                                 accordance with generally accepted accounting
                                 principles, consistently applied.

                                 "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 rating organization), certificates of
                                 deposit and banker's acceptances, and accounts
                                 receivable (net of allowance for doubtful
                                 accounts).

                                 "Stated net worth" means the excess of total
                                 assets over total liabilities (including but
                                 not limited to indebtedness which is
                                 subordinated to the indebtedness to Silicon),
                                 determined in 


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                                 accordance with generally accepted accounting
                                 principles, consistently applied..

                                 "Debt Service Ratio" means the year-to-date and
                                 annualized ratio of (a) earnings before
                                 interest, taxes, depreciation and other
                                 non-cash amortization expenses and other
                                 non-cash expenses of the Borrower, determined
                                 in accordance with generally accepted
                                 accounting principles, consistently applied,
                                 (other than for expenses of Borrower associated
                                 solely with the Acquisition) to (b) Borrower's
                                 obligations relating to payment of interest and
                                 current maturities of principal on Borrower's
                                 outstanding indebtedness, determined in
                                 accordance with generally accepted accounting
                                 principles, consistently applied. For purposes
                                 hereof, the annualized Debt Service Ratio for
                                 the quarter ending March 31, 1998 shall be such
                                 quarter's ratio multiplied by four; the
                                 annualized Debt Service Ratio for the quarter
                                 ending June 30, 1998 shall be the sum of such
                                 quarter's ratio plus the ratio for the prior
                                 quarter, which sum is then multiplied by two;
                                 the annualized Debt Service Ratio for the
                                 quarter ending September 30, 1998 shall be the
                                 sum of such quarter's ratio plus the ratio for
                                 each of the two preceding quarters, which sum
                                 is then multiplied by the fraction of 4/3.

    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."

        6. REPRESENTATIONS TRUE. Borrower represents and warrants to Silicon
that all representations and warranties set forth in the Loan Agreement, as
amended hereby, are true and correct.

        7. 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


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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.

                                   BORROWER:

                                      I-FLOW CORPORATION

                                      BY_______________________________
                                        TITLE:

                                      BY_______________________________
                                        TITLE:


                                   SILICON:

                                      SILICON VALLEY BANK

                                      BY_______________________________
                                        TITLE______________________________


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