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                                                                    Exhibit 10.4

                            DIAMETRICS MEDICAL, INC.

                         FORM OF STOCK PURCHASE WARRANT

THE WARRANTS EVIDENCED HEREBY AND THE SHARES OF STOCK ISSUABLE UPON EXERCISE
THEREOF HAVE NOT BEEN REGISTERED UNDER SECURITIES ACT OF 1933, AS AMENDED, AND
MAY NOT BE OFFERED OR SOLD WITHOUT REGISTRATION UNLESS AN EXEMPTION FROM
REGISTRATION IS AVAILABLE UNDER SUCH ACT OR THE RULES OR REGULATIONS PROMULGATED
THEREUNDER.

                                                                   April 7, 2003

                                     WARRANT

     To Subscribe for and Purchase Common Stock of Diametrics Medical, Inc.

               VOID AFTER 5:00 P.M., MINNEAPOLIS, MINNESOTA TIME,
         ON APRIL 7, 2008, OR IF NOT A BUSINESS DAY, AS DEFINED HEREIN,
                         AT 5:00 P.M, MINNEAPOLIS TIME,
                    ON THE IMMEDIATELY PRECEDING BUSINESS DAY

This certifies that, for valuable consideration, receipt of which is hereby
acknowledged,              , and permitted successors and assigns ("Holder") is
              -------------
entitled to purchase from Diametrics Medical, Inc. a Minnesota corporation (the
"Company"), up to and including              fully paid and nonassessable shares
                                ------------
(the "Number of Shares") of the common stock of the Company, $.01 par value (the
"Common Stock"), on the terms set forth herein at an exercise price per share
equal to $0.94 (the "Purchase Price"). The Number of Shares and the Purchase
Price may be adjusted from time to time as described in this Warrant.

This Warrant is issued pursuant to a First Amendment to Note Purchase Agreement
dated as of April 7, 2003 (the "First Amendment"), which amends a Note Purchase
Agreement dated as of August 4, 1998 among the Company and the other parties
identified therein (as amended, the "Note Purchase Agreement"). Capitalized
terms used in this Warrant and not otherwise defined will have the meanings
assigned to them in the First Amendment or the Note Purchase Agreement, as the
case may be.

1.   Exercise.

1.1 Time for Exercise. This Warrant may be exercised in whole or in part as to
the following percentages of the Number of Shares at any time and from time to
time during the period commencing on the respective dates set forth below and
expiring on the earliest to occur of (a) April 7, 2008, (b) the occurrence of a
Redemption Event on or prior to April 7, 2004 pursuant to which the Notes are
repaid in full, or (c) the repayment in full of the Notes on or prior to April
7, 2004 pursuant to Section 4.5 of the Note Purchase Agreement:

                    Cumulative Percentage of
     Date         Number of Shares Exercisable
     ----         ----------------------------

 April 7, 2004              33-1/3%
October 7, 2004             66-2/3%
 April 7, 2005                 100%

provided, however, that no such right shall be exercised to the extent that such
exercise will cause the Holder to beneficially own shares of the Company's
outstanding capital stock equal to or in excess of the Ownership Limit;
provided, further, that immediately prior to the occurrence of a Redemption
Event, the foregoing exercise limitations shall not apply and this Warrant may
be exercised in whole or in part with respect to100% of the Number of Shares
purchasable hereunder.

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1.2 Manner of Exercise. This Warrant shall be exercised by delivering it to the
Company with the exercise form duly completed and signed, specifying the number
of shares as to which the Warrant is being exercised at that time (the "Exercise
Number"). The Holder shall simultaneously deliver to the Company cash or a
certified check or wire transfer in an amount equal to the Exercise Number
multiplied by the Purchase Price, and the Holder shall be entitled to receive
the full Exercise Number of shares of Common Stock.

1.3 Effective Date of Exercise. Promptly (but in any case within ten (10)
business days) after any exercise, the Company shall deliver to the Holder (a)
duly executed certificates in the name or names specified in the exercise notice
representing the aggregate Exercise Number, and (b) if this Warrant is exercised
only in part, a new Warrant of like tenor exercisable for the balance of the
Number of Shares. Such certificates shall be deemed to have been issued, and the
person receiving them shall be deemed to be a holder of record of such shares,
as of the close of business on the date the actions required in Section 1.2
shall have been completed or, if on that date the stock transfer books of the
Company are closed, as of the next business day.

2.   Transfer of Warrants and Stock.

2.1 Transfer Restrictions. This Warrant shall be freely transferable by the
Holder in accordance with the terms hereof; provided, however, that neither this
Warrant nor the securities issuable upon its exercise may be sold, transferred
or pledged unless the Company shall have been supplied with reasonably
satisfactory evidence that such transfer is not in violation of the Securities
Act of 1933, as amended (the "Securities Act"), and any applicable state
securities laws. The Company may place a legend to that effect on this Warrant,
any replacement Warrant and each certificate representing shares issuable upon
exercise of this Warrant. Subject to the satisfaction of this condition only,
this Warrant shall be freely transferable by the Holder.

2.2 Manner of Transfer. Upon delivery of this Warrant to the Company with the
assignment form duly completed and signed, the Company will promptly (but in any
case within five (5) business days) execute and deliver to each transferee and,
if applicable, the Holder, Warrants of like tenor evidencing the rights (a) of
the transferee(s) to purchase the Number of Shares specified for each in the
assignment forms, and (b) of the Holder to purchase any untransferred portion,
which in the aggregate shall equal the number of Shares of the original Warrant.
If this Warrant is properly assigned in compliance with Section 2, it may be
exercised by an assignee without having a new Warrant issued.

2.3 Loss, Destruction of Warrant Certificates. Upon receipt of (a) evidence
reasonably satisfactory to the Company of the loss, theft, destruction or
mutilation of any Warrant and (b) except in the case of mutilation, an indemnity
or security reasonably satisfactory to the Company, the Company will promptly
(but in any case within five (5) business days) execute and deliver a
replacement Warrant of like tenor representing the right to purchase the same
Number of Shares.

3. Cost of Issuances. The Company shall pay all expenses, transfer taxes and
other charges payable in connection with the preparation, issuance and delivery
of stock certificates or replacement Warrants, except for any transfer tax or
other charge imposed as a result of (a) any issuance of certificates in any name
other than the name of the Holder, or (b) any transfer of the Warrant. The
Company shall not be required to issue or deliver any stock certificate or
Warrant until it receives reasonably satisfactory evidence that any such tax or
other charge has been paid by the Holder.

4. Anti-Dilution Provisions. If any of the following events occur at any time
hereafter during the life of this Warrant, then the Purchase Price and the
Number of Shares immediately prior to such event shall be changed as described
in order to prevent dilution:

4.1 Dividends, Stock Splits, Etc. In case the Company shall (a) pay a dividend
in shares of Common Stock or make a distribution in shares of Common Stock, (b)
subdivide or reclassify its outstanding shares of Common Stock into a greater
number of shares, or (c) combine or reclassify its outstanding shares of Common
Stock into a smaller number of shares, the Number of Shares purchasable upon the
exercise of this Warrant immediately prior thereto shall be adjusted so that the
Number of Shares purchasable upon exercise of this Warrant shall be determined
by

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multiplying the Number of Shares theretofore purchasable upon the exercise of
this Warrant by a fraction, of which the numerator shall be the number of shares
of Common Stock outstanding immediately following such action and of which the
denominator shall be the number of shares of Common Stock outstanding
immediately prior thereto. Such adjustment shall be made whenever any event
listed above shall occur and shall become effective immediately after the record
date in the case of a dividend and shall become effective immediately after the
effective date in the case of a subdivision, combination or reclassification. If
the Company declares a dividend in money on its Common Stock and at
substantially the same time offers its stockholders a right to purchase new
shares of Common Stock or of capital stock of any other class from the proceeds
of such dividend, or for an amount substantially equal to such dividend, all
shares of Common Stock or of capital stock of any other class so issued shall
for purposes hereof be deemed issued as a stock dividend.

4.2 Issuance of Rights or Warrants to Holders. In case the Company shall issue
rights, options or warrants to all holders of its shares of Common Stock
entitling them (for a period expiring within 45 days after the record date
therefor) to subscribe for or purchase shares of Common Stock at a price per
share which is lower at the record date mentioned below than the then Current
Market Price per share of Common Stock (as hereinafter defined), the Number of
Shares thereafter purchasable upon the exercise of this Warrant shall be
determined by multiplying the Number of Shares theretofore purchasable upon
exercise of this Warrant by a fraction, of which the numerator shall be the
number of shares of Common Stock outstanding on such record date plus the number
of additional shares of Common Stock offered for subscription or purchase, and
of which the denominator shall be the number of shares of Common Stock
outstanding on such record date plus the number of shares which the aggregate
offering price of the total number shares of Common Stock so offered would
purchase at the then Current Market Price per share of Common Stock. For
purposes of this Section 4.2, the issuance of rights, options or warrants to
subscribe for or purchase securities convertible into Common Stock shall be
deemed to be the issuance of rights, options or warrants to purchase the Common
Stock into which such securities are convertible at an aggregate offering price
equal to the aggregate offering price of such securities plus the minimum
aggregate amount (if any) payable upon conversion of such securities into Common
Stock.

4.3 Merger; Consolidation; Sale of Assets. In case of (a) the consolidation or
the merger of the Company, (b) the sale of all or substantially all of the
properties and assets of the Company to any person, (c) any capital
reorganization by the Company, or (d) any voluntary or involuntary dissolution,
liquidation or winding up of the Company, this Warrant shall, after any such
event, entitle the Holder to receive upon exercise the number of shares of stock
or other securities or property (including cash) of the person (if applicable)
resulting from such event, which the holder of securities deliverable upon
exercise of this Warrant (at the time of such event) would have been entitled to
receive upon such event; and in any such case the provisions of Section 4 with
respect to the rights and interests thereafter of the holders of this Warrant
shall be appropriately adjusted so as to be applicable, as nearly as
practicable, to any shares of stock or other securities or any property
(including cash) thereafter deliverable upon exercise of this Warrant. The
person resulting from such sale or consolidation or surviving such merger or to
which such sale shall be made shall execute and deliver to the Holder a
supplemental agreement as provided in Section 6.5 below. Any adjustment pursuant
to this Section 4.3 which shall be approved in good faith by the Board of
Directors of the Company pursuant to a resolution delivered to the Holder shall
be conclusive for all purposes hereof. For the purposes of this Agreement
"person" means any individual, partnership, firm, corporation, limited liability
company or partnership, association, trust, unincorporated organization or other
entity, as well as any syndicate or group that would be deemed to be a person
under Section 13(d)(3) of the Securities Exchange Act of 1934, as amended.

4.4 Other Distributions. In case the Company shall distribute to all holders of
its shares of Common Stock shares of stock other than Common Stock or evidences
of its indebtedness or assets (excluding cash dividends or distributions payable
out of consolidated earnings or retained earnings and dividends or distributions
referred to in Section 4.1 above) or rights, options, warrants or convertible or
exchangeable securities containing the right to subscribe for or purchase shares
of Common Stock (excluding those referred to in Section 4.2 above), then in each
case the Number of Shares thereafter purchasable upon the exercise of this
Warrant shall be determined by multiplying the Number of Shares theretofore
purchasable upon the exercise of this Warrant, by a fraction of which the
numerator shall be the Current Market Price per share of Common Stock on the
record date mentioned below in this Section 4.4 plus the then fair value (as
reasonably determined by the Board of Directors of the Company in good faith,
whose determination shall be conclusive absent manifest error, irrespective of
the accounting treatment thereof) of the portion of the shares of stock other
than Common Stock or assets or evidences of indebtedness so

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distributed or of such subscription rights, options or warrants, or of such
convertible or exchangeable securities applicable to one share of Common Stock,
and of which the denominator shall be the Current Market Price per share of
Common Stock on such record date. Such adjustment shall be made whenever any
such distribution is made, and shall become effective immediately after the
record date for the determination of stockholders entitled to receive such
distribution.

4.5 Additional Adjustment of Purchase Price. Whenever the Number of Shares
purchasable upon the exercise of this Warrant is adjusted, as provided herein,
the Purchase Price payable upon exercise of this Warrant shall be adjusted by
multiplying such Purchase Price immediately prior to such adjustment by a
fraction, of which the numerator shall be the Number of Shares purchasable upon
the exercise of this Warrant immediately prior to such adjustment, and of which
the denominator shall be the Number of Shares so purchasable immediately
thereafter.

4.6 No De Minimis Adjustments. No adjustment in the Purchase Price shall be
required unless such adjustment would require an increase or decrease of at
least 1% in such price; provided, however, that any adjustments which by reason
of this Section 4.6 are not required to be made shall be carried forward and
taken into account in any subsequent adjustment. All calculations under this
Section 4.6 shall be made to the nearest one-twentieth of a cent or to the
nearest one-hundredth of a share, as the case may be.

4.7 Treasury Shares. For the purpose of Section 4, shares of Common Stock or
other securities held in the treasury of the Company shall not be deemed to be
outstanding, and the sale or other deposition of any shares of Common Stock or
other securities held in the treasury of the Company shall be deemed an issuance
thereof.

4.8 Corporate Action. Before taking any action which would cause an adjustment
reducing the Purchase Price below the then par value, if any, of the shares of
Common Stock issuable upon exercise of this Warrant, the Company shall take any
corporate action which may, in the opinion of its counsel, be necessary in order
that the Company may validly and legally issue fully paid and nonassessable
shares of Common Stock at such adjusted Purchase Price.

4.9 Independent Public Accountants. The certificate of a "Big Four" firm of
independent public accountants selected by the Board of Directors of the Company
shall be conclusive evidence of the correctness of any computation made under
Section 4.

4.10 Notice of Certain Events. In case at any time prior to the expiration date
of this Warrant:

(i) the Company shall declare a dividend (or any other distribution) on the
Common Stock (other than a dividend in cash out of retained earnings); or

(ii) the Company shall authorize the granting to the holders of Common Stock of
rights or warrants to subscribe for or purchase any shares of stock of any class
or of any other rights; or

(iii) there shall be any reclassification of the Common Stock of the Company
(other than a subdivision or combination of its outstanding Common Stock); or

(iv) there shall be any capital reorganization by the Company; or

(v) there shall be a consolidation or merger involving the Company or sale of
all or substantially all of the Company's property and assets (except a merger
or other reorganization in which the Company shall be the surviving corporation
or a consolidation, merger or sale with a wholly-owned subsidiary); or

(vi) there shall be voluntary or involuntary dissolution, liquidation and
winding up by the Company or dividend or distribution to holders of Common Stock
(other than the customary cash and stock dividends); or

(vii) there shall be a Redemption Event; or

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(viii) any other action shall occur which would give rise to an adjustment to
the Purchase Price or the Number of Shares hereunder,

then in any one or more of said cases, the Company shall cause to be delivered
to the Holder, at the earliest practicable time (and, in any event, not less
than 25 days before any record date or other date set for definitive action),
notice of the date on which the books of the Company shall close or a record
shall be taken for such dividend, distribution or subscription rights or such
reorganization, sale, consolidation, merger, dissolution, liquidation or winding
up shall take place, as the case may be. Such notice shall also set forth such
facts as shall indicate the effect of such action (to the extent such effect may
be known at the date of such notice) on the Purchase Price and the kind and
amount of the shares of stock and other securities and property deliverable upon
exercise of this Warrant. Such notice shall also specify the date, if known, as
of which the holders of record of the Common Stock shall participate in said
dividend, distribution or subscription rights or shall be entitled to exchange
their shares of the Common Stock for securities or other property (including
cash) deliverable upon such reorganization, sale, consolidation, merger,
dissolution, liquidation or winding up, as the case may be (on which date, in
the event of voluntary or involuntary dissolution, liquidation, or winding up of
the Company, other than dissolution, liquidation or winding up following a
consolidation or merger of the Company with or into, or sale of substantially
all of its assets to, another corporation, the rights to exercise this Warrant
shall terminate).

4.11 Other Securities Adjustments. If as a result of Section 4, a Holder is
entitled to receive any securities other than Common Stock upon exercise of this
Warrant, the number and purchase price of such securities shall thereafter be
adjusted from time to time in the same manner as provided pursuant to Section 4
for Common Stock. The allocation of purchase price between various securities
shall be made in writing by the Board of Directors of the Company in good faith
at the time of the event by which the holder became entitled to receive new
securities, and a copy sent to the Holder.

4.12 Notices of Adjustments. When any adjustment is required to be made under
Section 4, the Company shall promptly (a) determine such adjustments, (b)
prepare and retain on file a statement describing in reasonable detail the
method used in arriving at the adjustment; and (c) cause a copy of such
statement, together with any agreement required by Section 6.5, to be mailed to
the Holder within 10 days after the date on which the circumstances giving rise
to such adjustment occurred.

4.13 Computations and Adjustments. Upon each computation of an adjustment under
this Section 4, the Purchase Price shall be computed to the nearest cent and the
Number of Shares shall be calculated to the next highest whole share. However,
the fractional amount shall be used in calculating any future adjustments. No
fractional shares of Common Stock shall be issued in connection with the
exercise of this Warrant, but the Company shall, in the case of the final
exercise under this Warrant, make a cash payment for any fractional shares based
on the Current Market Price of the Common Stock on the date of exercise.
Notwithstanding any changes in the Purchase Price or the Number of Shares, this
Warrant, and any Warrants issued in replacement or upon transfer thereof, may
continue to state the initial Purchase Price and the Number of Shares.
Alternatively, the Company may elect to issue a new Warrant or Warrants of like
tenor for the additional shares of Common Stock purchasable hereunder or, upon
surrender of the existing Warrant, to issue a replacement Warrant evidencing all
the Warrants to which the Holder is entitled after such adjustments.

4.14 Exercise Before Payment Date. In the event that this Warrant is exercised
after the record date for any event requiring an adjustment, but prior to the
actual event, the Company may elect to defer payment of the adjusted amount to
the Holder until the actual event occurs; provided, however, that the Company
shall deliver a due bill or other appropriate instrument to the Holder
transferable to the same extent as the other securities issuable on exercise
evidencing the Holder's right to receive such additional amount upon the
occurrence of the event requiring such adjustment.

4.15 Current Market Price. "Current Market Price" for the Common Stock on any
given date means (a) the closing price on the previous trading day for the
Common Stock on the principal stock exchange on which the Common Stock is traded
(or, in the case of issuances of stock options with an exercise price equal to
fair market value on the date of grant pursuant to the terms of a plan, such
date) or (b) if not so traded, the closing price (or, if no closing price is
available, the average of the bid and asked prices) for such date on the NASDAQ
if the Common

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Stock is listed on the NASDAQ or (c) if not listed on any exchange or
quoted on the NASDAQ, such value as may be determined in good faith by the
Company's Board of Directors, which determination shall be conclusively binding
on the parties.

5.   [RESERVED].

6.   Covenants. The Company agrees that:

6.1 Reservation of Stock. During the period in which this Warrant may be
exercised, the Company will reserve sufficient authorized but unissued
securities to enable it to satisfy its obligations on exercise of this Warrant
and shall use its reasonable best efforts to cause all shares of Common Stock
issued upon the exercise of this Warrant to be listed on any exchanges on which
the Common Stock is then listed. If at any time the Company's authorized
securities shall not be sufficient to allow the exercise of this Warrant, the
Company shall take such corporate action as may be necessary to increase its
authorized but unissued securities to be sufficient for such purpose;

6.2 No Liens, etc. All securities that may be issued upon exercise of this
Warrant will, upon issuance, be validly issued, fully paid, nonassessable and
free from all taxes, liens and charges with respect to the issue thereof, and
shall be listed on any exchanges on which that class of securities is listed;

6.3 Furnish Information. During the term of this Warrant, the Company will
promptly deliver to the Holder copies of all financial statements, reports and
proxy statements which the Company shall have sent to its shareholders
generally;

6.4 Stock and Warrant Transfer Books. Except upon dissolution, liquidation or
winding up or for ordinary holidays and weekends, the Company will not at any
time close its stock or warrant transfer books so as to result in preventing or
delaying the exercise or transfer of this Warrant; and

6.5 Merger; Consolidation or Sale of Assets of the Company. Except in the case
of a merger or consolidation where the consideration is payable entirely in cash
or obligations, the Company will not merge or consolidate with or into any
Person, or sell or otherwise transfer its property, assets and business
substantially as an entirety to a successor Person, unless the Person resulting
from such merger or consolidation (if not the Company), or such successor
Person, shall expressly assume, by supplemental agreement reasonably
satisfactory in form to the then Majority Holders (as defined below) and
executed and delivered to the Holder, the due and punctual performance and
observance of each and every covenant and condition of this Agreement to be
performed and observed by the Company. "Majority Holders", as of any date, shall
mean the holders of this Warrant (or replacement warrants issued pursuant
hereto) and of the substantially similar warrants issued contemporaneously
herewith pursuant to the First Amendment (or replacement warrants issued
pursuant thereto) who together have rights to exercise such warrants for a
majority of the First Amendment Warrant Shares (as defined in the First
Amendment).

7.   Status of Holder.

7.1 Not a Stockholder. Unless the Holder exercises this Warrant in writing, the
Holder shall not be entitled to any rights (a) as a stockholder of the Company
with respect to the shares as to which the Warrant is exercisable including,
without limitation, the right to vote or receive dividends or other
distributions, or (b) to receive any notice of any proceedings of the Company
except as otherwise provided in this Warrant.

7.2 Limitation of Liability. Unless the Holder exercises this Warrant in
writing, the Holder's rights and privileges hereunder shall not give rise to any
liability for the Purchase Price or as a stockholder of the Company, whether to
the Company or its creditors.

8. Registration Rights. The shares purchasable upon exercise of this Warrant
shall be Registrable Securities as defined in Section 8 of the First Amendment.

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9.   General Provisions.

9.1 Complete Agreement; Modifications. This Warrant and any documents referred
to herein or executed contemporaneously herewith constitute the parties' entire
agreement with respect to the subject matter hereof and supersede all
agreements, representations, warranties, statements, promises and
understandings, whether oral or written, with respect to the subject matter
hereof. The Warrant may be amended, altered or modified, and observance of any
of its provisions may be waived, either prospectively or retroactively, by a
writing signed by the Majority Holders and each Holder, by acceptance of this
Warrant, agrees to be bound by any amendment, alteration, modification or waiver
so approved. In the event of any such amendment, alteration, modification or
waiver, the Company shall give prompt written notice thereof to the Holder,
including a copy of the writing effecting such amendment, alteration,
modification or waiver; provided, however, that failure to give such notice
shall not invalidate such amendment, alteration, modification or waiver.

9.2 Cooperation. Each party hereto agrees to execute any and all further
documents and writings and to perform such other reasonable actions which may be
or become necessary or expedient to effectuate and carry out this Warrant.

9.3 Notices. All notices under this Warrant shall be in writing and shall be
delivered by personal service or telecopy or certified mail return receipt
requested (if such service is not available, then by first class mail), postage
prepaid, to such address as may be designated from time to time by the relevant
party, and which shall initially be:

(a)  If to the Company:

          Diametrics Medical, Inc.
          2658 Patton Road
          Roseville, MN 55113
          Attention: Chief Financial Officer
          Phone: (651) 639-8035
          Telecopy: (612) 639-8459

          with a copy to:

          Dorsey & Whitney LLP
          50 South Sixth Street, Suite 1500
          Minneapolis, MN 55402
          Attention: Kenneth Cutler, Esq.
          Phone: (612) 340-2740
          Telecopy: (612) 340-7800

(b)  If to the Holder:

          [Purchaser]
          c/o Bay City Capital LLC
          750 Battery Street, Suite 600
          San Francisco, CA 94111
          Attention: Fred Craves
          Phone: (415) 676-3830
          Fax: (415) 837-0996

          with a copy to:

          Latham & Watkins Illinois LLC
          Sears Tower, Suite 5800
          Chicago, IL 60606
          Attention: Michael Pucker and Thomas E. Keim, Jr.

                                       7

<PAGE>

          Phone: (312) 876-7700
          Fax: (312) 993-9767

Any notice sent by certified mail shall be deemed to have been given three (3)
days after the date on which it is mailed. All other notices shall be deemed
given when received. No objection may be made to the manner of delivery of any
notice actually received in writing by an authorized agent of a party.

9.4 No Third-Party Benefits; Successors and Assigns. None of the provisions of
this Warrant shall be for the benefit of, or enforceable by, any third-party
beneficiary. Except as provided herein to the contrary, this Warrant shall be
binding upon and inure to the benefit of the parties, their respective
successors and permitted assigns.

9.5 Governing Law. This Warrant concerns a Minnesota corporation, and all
questions with respect to the Warrant and the rights and liabilities of the
parties will be governed by the laws of Minnesota regardless of the choice of
law provisions of Minnesota or any other jurisdiction.

9.6 Waivers Strictly Construed. With regard to any power, remedy or right
provided herein or otherwise available to any party hereunder, no alteration,
modification or impairment shall be implied by reason of any previous waiver,
extension of time, delay or omission in exercise, or other indulgence.

9.7 Severability. The validity, legality or enforceability of the remainder of
this Warrant shall not be affected even if one or more of its provisions shall
be held to be invalid, illegal or unenforceable in any respect.

9.8 Attorneys' Fees. Should any litigation or arbitration be commenced
(including any proceedings in a bankruptcy court) between the parties hereto or
their representatives concerning any provisions of this Warrant or the rights
and duties of any person or entity hereunder the party or parties prevailing in
such proceeding shall be entitled, in addition to such other relief as may be
granted, to the attorneys' fees and court costs incurred by reason of such
litigation.

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     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed
as of the date and year first above written.

                                    DIAMETRICS MEDICAL, INC.


                                    By:
                                        ----------------------------------------
                                    Name: David Kaysen
                                    Title: Chief Executive Officer and President

                   [Signature Page to Stock Purchase Warrant]
                                      S - 1

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                                 ASSIGNMENT FORM

FOR VALUE RECEIVED,                                  hereby sells, assigns and
                    --------------------------------
transfers to the transferee named below the rights to purchase                of
                                                               --------------
the Number of Shares under this Warrant, together with all rights, title and
interest therein. The rights to purchase the remaining Number of Shares shall
remain the property of the undersigned.

Dated:
       ------------------

                                 [NAME OF HOLDER]


                                 By
                                    --------------------------------------------
                                 Name
                                      ------------------------------------------
                                 (Please Print)

                                 Address:
                                          --------------------------------------

                                 -----------------------------------------------

                                 -----------------------------------------------

                                 Employer Identification Number, Social Security
                                 Number or other identifying number:

                                 -----------------------------------------------

<PAGE>

                                  EXERCISE FORM
                     To Be Executed Upon Exercise Of Warrant

The undersigned hereby exercises the Warrant with regard to             shares
                                                            -----------
of Common Stock and herewith makes payment of the purchase price in full. The
undersigned requests that certificate(s) for such shares and the Warrant for any
unexercised portion of this Warrant be issued to the Holder.

Dated:
       ------------------

                                 [NAME OF HOLDER]


                                 By
                                    --------------------------------------------
                                 Name
                                      ------------------------------------------
                                 (Please Print)

                                 Address:
                                          --------------------------------------

                                 -----------------------------------------------

                                 -----------------------------------------------

                                 Employer Identification Number, Social Security
                                 Number or other identifying number:

                                 -----------------------------------------------