<PAGE>

                                                                   Exhibit 10.18
                                ESCROW AGREEMENT

     THIS ESCROW AGREEMENT (this "Agreement"), dated as of ___________ __, 2001,
is made and entered into by and among Cardiac Science, Inc., a Delaware
corporation ("Parent"), a committee consisting of a representative of U.S.
Trust, a representative of Fidelity Investments and Mark Wagner ("Shareholders'
Representative") and [Bank] (the "Escrow Agent").

     WHEREAS, pursuant to a First Amended and Restated Agreement and Plan of
Merger (the "Merger Agreement"), dated as of June 5, 2001, by and among Parent,
Cardiac Science Acquisition Corp., a Minnesota corporation ("Merger Sub"), and
Survivalink Corporation, a Minnesota corporation (the "Company"), the Company
shall be merged with and into Merger Sub.  Capitalized terms used but not
defined in this Agreement shall have the respective meanings ascribed to them in
the Merger Agreement.

     WHEREAS, pursuant to the Merger Agreement, the Company Outstanding Shares
will be cancelled and coverted into the right to receive from Parent the Total
Merger Consideration, payable in cash, Parent Common Stock and Parent Notes, as
described in the Merger Agreement.

     WHEREAS, pursuant to section 2.4 of the Merger Agreement, at the Effective
Time of the Merger, Parent shall deposit an amount equal to 5% of Total Merger
Consideration payable to the holders of the Company Outstanding Shares (the
"Shareholders") in an escrow account with the Escrow Agent.

     WHEREAS, the obligations of Parent, Merger Sub and the Company to
consummate the Merger are contingent, among other things, upon the execution and
delivery of this Agreement.

     WHEREAS, the Escrow Agent is willing to act as escrow agent on the terms
and conditions set forth in this Agreement.

     NOW, THEREFORE, in consideration of the premises, the mutual covenants and
agreements contained in this Agreement and in the Merger Agreement, and other
good and valuable consideration, the receipt and adequacy of which are hereby
acknowledged, Parent, Shareholders' Representative and the Escrow Agent agree as
follows:

    1. Designation of Escrow Agent and Amount of Escrow Fund. The Escrow Agent
       -----------------------------------------------------
is hereby appointed escrow agent to hold and dispose of the escrow amount
provided for in Section 2.4 of the Merger Agreement in accordance with the terms
and conditions set forth in this Agreement, and the Escrow Agent accepts such
designation and agrees to hold and dispose of such escrow amount in accordance
with the provisions of this Agreement. Concurrently with the execution of this
Agreement, Parent will deposit with the Escrow Agent $_______ face value of
Parent Notes (the "Escrow Notes") and ________ shares of Common Stock (the
"Escrow Shares" and, together with the Escrow Notes, the "Escrow Fund") The
Escrow Notes and Escrow Shares shall be in the form of duly authorized stock
certificates and notes dated the Effective Date issued in the names of each of
the Shareholders (as set forth in Annex A), such amount being a portion of the
Total Merger Consideration payable to the Shareholders by Parent pursuant to the
Merger Agreement. The Escrow Agent hereby acknowledges receipt of the Escrow
Fund.

<PAGE>

     2.  Escrow Share and Escrow Note Matters.
         ------------------------------------

     (a)  Dividends, Voting and Rights of Ownership. Except for tax-free
          -----------------------------------------
dividends paid in stock declared with respect to the Escrow Shares pursuant to
Section 305(a) of the Code ("Additional Escrow Shares"), any cash dividends,
dividends payable in securities or other distributions of any kind made in
respect of the Escrow Shares will be distributed currently by Parent to the
Shareholders. The Shareholders will have the right to vote the Escrow Shares
deposited in its Escrow Account so long as such Escrow Shares are held in
escrow, and Parent will take all reasonable steps necessary to allow the
exercise of such rights. While the Escrow Shares remain in the Escrow Agent's
possession pursuant to this Agreement, the Shareholders will retain and will be
able to exercise all other incidents of ownership of said Escrow Shares that are
not inconsistent with the terms and conditions hereof.

     (b)  No Encumbrance.  No Escrow Shares or Escrow Notes or any beneficial
          --------------
interest therein may be pledged, sold, assigned or transferred, including by
operation of law, by the Shareholders or be taken or reached by any legal or
equitable process in satisfaction of any debt or other liability of the
Shareholders, prior to the delivery to the Shareholders of the Escrow Shares or
Escrow Notes by the Escrow Agent.

     (c)  Power to Transfer Escrow Shares and Escrow Notes.  The Escrow Agent is
          -------------------------------------------------
hereby granted the power to effect any transfer or cancellation of Escrow Shares
or Escrow Notes contemplated by this Agreement. Parent and its transfer agent
will cooperate with the Escrow Agent in promptly issuing stock certificates to
effect such transfers of Escrow Shares.

     3.  Escrow Fund Claim and Disbursement Procedures.
         ---------------------------------------------

     (a)  Initiation of Claim Procedure for Indemnification or Reimbursement. In
          ------------------------------------------------------------------
the event Parent or any of its affiliates, officers, directors, employees,
agents, successors or assigns (a "Claimant") proposes to make any claim under
the Merger Agreement for which the Escrow Fund is available to indemnify such
Claimant, it shall assert such claim in the form of a certificate signed by the
Claimant ("Officer's Certificate") delivered to the Escrow Agent (with a
duplicate copy thereof being delivered concurrently to Shareholders'
Representative). The Escrow Agent shall promptly send a copy of the Officer's
Certificate to Shareholders' Representative after receipt of the same from the
Claimant. The Officer's Certificate shall specify in reasonable detail the
nature, the basis, and the amount or estimated amount of the Claimant's claim.

     (b)  Shareholders' Representative Objection. Shareholders' Representative
          --------------------------------------
shall have thirty (30) days after receipt of any Officer's Certificate in which
to object in writing to the claim or claims made by the Claimant in the
Officer's Certificate, which written objection (the "Objection Notice") shall
state, in reasonable detail, the basis for the Shareholders' Representative's
objection. In the event the Escrow Agent does not receive an Objection Notice
within such thirty (30) day period, the Escrow Agent shall make distributions to
the Claimant in accordance with Section 3(d) of this Agreement. However, no such
distribution shall be made with respect to those matters specified in the
Objection Notice delivered within such thirty (30) day period. A duplicate copy
of the Objection Notice shall be delivered to the Claimant at the same time it
is delivered to the Escrow Agent.

                                       2
<PAGE>

     (c)  Negotiated Settlement of Claims. In the event that Shareholders'
          -------------------------------
Representative timely delivers an Objection Notice with respect to any claim or
claims made in an Officer's Certificate, Shareholders' Representative and the
Claimant's duly authorized representatives shall, within the sixty (60) day
period beginning as of the date of the receipt by the Claimant of the Objection
Notice or such extended period as Claimant and Shareholders' Representative
shall mutually agree upon in writing, attempt in good faith to agree upon the
proper resolution of each of such claims. If the parties should so agree, a
memorandum setting forth such agreement shall be prepared and signed by both
parties and shall be furnished to the Escrow Agent. The Escrow Agent shall be
entitled to rely on any such memorandum to make distributions from the Escrow
Fund in accordance with the terms of such memorandum and Section 3(d) of this
Agreement. Escrow Agent shall further be entitled to rely upon the order of a
court of competent jurisdiction.

     (d) Escrow Fund Payment. Upon (i) the expiration of the thirty (30) day
         -------------------
period described in Section 3(b) without the delivery of an Objection Notice in
cases covered by Section 3(b) of this Agreement, (ii) the delivery of a
memorandum of agreement, in cases covered by Section 3(c) of this Agreement, or
(iii) the order of a court of competent jurisdiction, in cases covered by
Section 14 of this Agreement, the Escrow Agent shall, as promptly as
practicable, deliver to the Claimant out of the Escrow Fund an amount necessary,
to reimburse Claimant for such damages, losses or expenses (the "Damages") as
are specified in the joint instruction, the Officer's Certificate, or the
memorandum of agreement, as the case may be. Payments to be made by the Escrow
Agent pursuant to this Section 3 shall be satisfied (a) one-half through
cancellation of a portion of the Escrow Notes (or, in the event that Parent has
paid in full the Escrow Notes, one-half in cash), and (b) one-half by delivery
of Common Stock (or the cash proceeds thereof) from the Escrow Shares. The face
value of the Escrow Notes to be canceled (or, in the event that Parent has paid
in full the Escrow Notes, the cash to be paid) in satisfaction of a claim for
Damages shall be one-half of the amount of such Damages and the number of Escrow
Shares to be forfeited by the Shareholders and transferred to Parent in
satisfaction of a claim for Damages shall be one-half of the amount of such
Damages divided by the Parent Common Stock Price (as defined in the Merger
Agreement), provided however, that the Shareholders' Representative may elect,
in his sole discretion, to instruct the Escrow Agent to make any payment for
Damages solely through cancellation of the Escrow Notes (or, in the event that
Parent has paid in full the Escrow Notes, in cash). Escrow Notes canceled (or
cash paid) and Escrow Shares forfeited shall be canceled or forfeited by the
Shareholders pro rata in proportion to their respective percentage interests in
the Escrow Notes and Escrow Shares as set forth on Annex A.

     (e)  Subsequent Instructions. Notwithstanding the other provisions of this
          -----------------------
Section 3, Shareholders' Representative and Parent may jointly instruct the
Escrow Agent in writing as to the distribution of all or part of the Escrow
Fund. Promptly after the Escrow Agent's receipt of such instructions, the Escrow
Agent shall distribute the Escrow Fund in accordance with such instructions.

     4.  Distribution of Escrow Fund.
         ---------------------------

     (a)  Termination. On the date one (1) year after the Effective Date,
          -----------
subject to the provisions of this Section 4, the Escrow Agent shall deliver to
the Shareholders the then-existing full balance of the Escrow Fund for
distribution according to the percentages set forth on

                                       3
<PAGE>

Annex A, unless at that time there exists any claim(s) specified in Officer's
Certificates received by the Escrow Agent in accordance with Section 3 prior to
such time that have not been paid or resolved. In such case, the Escrow Agent
shall retain in the Escrow Fund an amount equal to one hundred percent (100%) of
such pending claim(s), and only the remaining balance shall be delivered to the
Shareholders. With respect to such outstanding claims, this Agreement shall
remain in effect until such claims have been resolved in accordance with the
procedures set forth in Sections 3(b), 3(c), 3(d), and/or 3(e) of this
Agreement. Following the resolution of such pending claim(s), the Escrow Agent
shall deliver the remaining balance of the Escrow Fund, if any, to the
Shareholders according to the percentages set forth on Annex A hereto.

     (b)  Tax Distributions. Parent agrees and undertakes to comply with any
          -----------------
reporting or withholding obligations under applicable law. The Escrow Agent
agrees to provide to Parent any information requested by Parent in connection
with such reporting or withholding obligations. In addition, Shareholders'
Representative agrees to take such further action, and hereby authorizes Parent
to take such further action, as Parent and its legal counsel determine to be
reasonably necessary or appropriate to comply with reporting or withholding
obligations under applicable law.

     5.  Escrow Agent's Disclaimers. The obligations of the Escrow Agent under
         --------------------------
this Agreement are subject to the following terms and conditions:

     (a)  The Escrow Agent is not a party to and is not bound by any agreement
other than expressly set forth in this Agreement.

     (b)  The Escrow Agent acts hereunder as a depository only and is not
responsible for or liable in any manner whatsoever for the sufficiency,
correctness, genuineness or validity of any funds, documents or other materials
deposited with it. To the extent that the Escrow Agent delivers any shares,
funds or documents in accordance with the instructions contained in this
Agreement, the party receiving such payment or delivery shall indemnify and hold
harmless the Escrow Agent from and against any loss, liability, claim or demand
arising out of or in connection with such delivery or payment. The Escrow Agent
shall not be required to defend any legal proceeding which may be instituted
against it with respect to the subject matter of this Agreement unless it is
requested to do so by one of the parties and is indemnified by such requesting
party to the Escrow Agent's reasonable satisfaction against the cost and
expenses including attorneys' fees of such defense, unless arising from the
Escrow Agent's bad faith or willful misconduct. The Escrow Agent shall not be
required to institute legal proceedings of any kind. The Escrow Agent shall not
be required to perform any acts which will violate any law or applicable rules
of any governmental agency.

     (c)  The Escrow Agent shall not have any responsibility for the genuineness
or validity of any notice, evidence of other documents or items received by it,
and the Escrow Agent shall be entitled to rely upon and shall be protected in
acting upon any written notice, waiver, consent, receipt, joint instruction,
memorandum of agreement or other evidence or paper or document which the Escrow
Agent reasonably believes to be genuine and to be signed by a proper person.

                                       4
<PAGE>

     (d)  The Escrow Agent shall not be liable for any error of judgment, in
investment or otherwise, or for any acts done or steps taken or omitted or
admitted by it or for any mistake of fact or law or for anything which the
Escrow Agent may do or refrain from doing in connection herewith except for the
Escrow Agent's own willful default or gross negligence or breach of this
Agreement.

     (e)  For purposes of tax reporting, the Escrow Agent shall be responsible
only for reporting interest income and issuing Form 1099-INT.

     6.  Escrow Agent's Fee.  As compensation for acting as escrow agent
         ------------------
pursuant to this Agreement, the Escrow Agent shall be paid the fees set forth on
Schedule A to this Agreement. The fees charged by the Escrow Agent for acting as
escrow agent pursuant to this Agreement shall be paid by Parent.

     7.  Notices.  Any notices or other communications to be given or delivered
         -------
under or by reason of the provisions of this Agreement will be in writing and
will be deemed to have been given when personally delivered or mailed by first
class mail, return receipt requested, or when sent by Federal Express or other
overnight delivery service, or when receipt is acknowledged, if sent by
facsimile, telecopy or other electronic transmission device. Any notices
required to be given to any party to this Agreement shall be given
contemporaneously to all of the parties to this Agreement. Notices and other
communications to the Escrow Agent, Parent and the Shareholders' Representative
will, unless another address is specified in writing, be sent to the address
indicated below:

   Notices to Escrow Agent:                  [Bank]
   -----------------------
                                             Attn:
                                             [Address]
                                             Fax:

   Notices to Parent:                        Cardiac Science, Inc.
   -----------------                         16931 Millikan Avenue
                                             Irvine, California 92606
                                             Fax: (949) 951-7315
                                             Attn: Raymond Cohen, President


   with a copy to:                           Stradling, Yocca, Carlson & Rauth
   --------------                            660 Newport Center Drive
                                             Suite 1600
                                             Newport Beach, California 92660
                                             Fax: (949) 725-4100
                                             Attn: Shivbir S. Grewal


   Notices to Shareholders' Representative:  U.S. Trust
   ---------------------------------------   114 West 47th Street
                                             New York, NY 10036
                                             Facsimile No.:(212)852-3759
                                             Attention: David I. Fann

                                       5
<PAGE>

   with a copy to:                       Dorsey & Whitney LLP
   --------------                        220 South Sixth Street
                                         Minneapolis, Minnesota 55402
                                         Fax: (612) 340-8827
                                         Attn: Michael McDonnell


     8.  Books and Records.  The Escrow Agent shall maintain books and records
         -----------------
regarding its administration of the Escrow Fund, including deposits,
investments, collections and disbursements or transfers, shall retain copies of
all written notices and directions sent or received by it in the performance of
its duties under this Agreement, and shall afford Parent and Shareholders'
Representative reasonable access during regular business hours to review and
make photocopies (at such party's cost) of the same. The Escrow Agent shall
provide Parent and Shareholders' Representative with accounting statements on a
quarterly basis.

     9.  Entire Agreement.  This Agreement and the Merger Agreement contain the
         ----------------
entire agreement among the parties with respect to the subject matter hereof.
In the event of a conflict between the terms and provisions of this Agreement
and of the Merger Agreement, the terms and provisions of this Agreement shall
govern.

     10.  Amendment, Etc.  This Agreement may not be amended, supplemented or
          --------------
discharged, and no provision of this Agreement may be modified or waived, except
by a written instrument signed by Parent, Shareholders' Representative and the
Escrow Agent.

     11.  Waiver.  No waiver of any provision of this Agreement by any party
          ------
shall be deemed a continuing waiver of any matter by such party. Shareholders'
Representative shall have the authority to waive the application of any
provision of this Agreement on behalf of the Shareholders, and any such waiver
shall be binding on all of the Shareholders.

     12.  Counterparts.  This Agreement may be executed in several counterparts,
          ------------
each of which shall be deemed an original, but such counterparts together shall
constitute one and the same instrument.

     13.  Headings.  The section headings contained in this Agreement are for
          --------
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

     14.  Settlement of Disputes.  Any dispute which may arise under this
          ----------------------
Agreement with respect to the delivery and/or ownership or right of possession
of the Escrow Fund or any part thereof, or the duties of the Escrow Agent
hereunder, shall be settled either by mutual agreement of the Shareholders'
Representative and Parent or, failing such agreement, either the Shareholders'
Representative or Parent shall have the right to submit the dispute to any
federal or state court in the States of California or Minnesota. Each party
waives any objection which it may now or hereafter have to the laying of venue
of any such proceeding, and irrevocably submits to the jurisdiction of such
courts in any such suit, action or proceeding. The Escrow Agent shall be under
no duty whatsoever to institute or defend any such proceedings. Prior to the
settlement of any such dispute, the Escrow Agent is authorized and directed to
retain in its possession, without liability to anyone, that portion of the
Escrow Fund which is the subject of such dispute.

                                       6
<PAGE>

     15.  Governing Law.  This Agreement shall be governed by and interpreted in
          -------------
accordance with the laws of the State of Delaware, without reference to
Delaware's conflict of laws principles, and shall be binding on the successors
and assigns of the parties hereto.

           [The balance of this page is intentionally left blank.
                         The signature page follows.]

                                       7
<PAGE>

                                                                   Exhibit 10.18

         IN WITNESS WHEREOF, Shareholders' Representative, Parent and the Escrow
Agent have executed this Agreement as of the date set forth in the first
paragraph.



                                          SHAREHOLDERS' REPRESENTATIVE



                                        DRAFT
                                        ----------------------------------------
                                        Mark Wagner


                                        DRAFT
                                        ----------------------------------------
                                        [Representative of U.S. Trust]


                                        DRAFT
                                        ----------------------------------------
                                        [Representative of Fidelity Investments]



                                        PARENT

                                        Cardiac Science, Inc.


                                        By: DRAFT
                                           -------------------------------------
                                           Its:
                                               ---------------------------------


                                        ESCROW AGENT


                                        [Bank]


                                        By: DRAFT
                                           -------------------------------------
                                           Its:
                                               ---------------------------------

<PAGE>

                                  SCHEDULE A
                                      TO
                               ESCROW AGREEMENT

                           ESCROW AGENT FEE SCHEDULE

<PAGE>

                                    ANNEX A
                                      TO
                               ESCROW AGREEMENT

                      ALLOCATION OF ESCROW FUND PROCEEDS



                      Amount of Initial Deposit of Merger
                               Consideration into
                                  Escrow Fund                      Allocation
Shareholder           Escrow Notes          Escrow Shares          Percentage
-----------           -----------------------------------          ----------