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                                                                     Exhibit 5.2

                                  April 5, 2004


Medex, Inc.
MedVest Holdings Corporation
Medex Medical, Inc.
Medex Cardio-Pulmonary, Inc.
2231 Rutherford Road
Carlsbad, California 92008

   RE:  REGISTRATION STATEMENT ON FORM S-4 OF MEDEX, INC.

Ladies and Gentlemen:

          We have acted as special counsel to Medex, Inc., an Ohio
corporation ("MEDEX"), MedVest Holdings Corporation, an Ohio corporation and
sole shareholder of Medex ("MEDVEST"), Medex Cardio-Pulmonary, Inc, an Ohio
corporation and wholly-owned subsidiary of Medex ("MEDEX CARDIO-PULMONARY"),
Medex Medical, Inc., an Ohio corporation and wholly-owned subsidiary of Medex
("MEDEX MEDICAL" and together with Medex Cardio-Pulmonary, Medex and MedVest,
the "MEDEX PARTIES" and each, individually, a "MEDEX PARTY"), in connection
with the preparation of the Registration Statement on Form S-4 (the
"REGISTRATION STATEMENT"), to be filed with the Securities and Exchange
Commission (the "COMMISSION"), on behalf of Medex and the other Medex
Parties, relating to Medex's offer to exchange Medex's currently outstanding
$200 million aggregate principal amount of 8 7/8% senior subordinated notes
due 2013 (the "OLD NOTES") and related guarantees (the "OLD GUARANTEES"), for
an equivalent principal amount of Medex's 8 7/8% senior subordinated notes
due 2013 (the "EXCHANGE NOTES") and related guarantees (the "EXCHANGE
GUARANTEES"), all as more fully described in the Registration Statement. The
Exchange Notes and Exchange Guarantees will be issued under Medex's
Indenture, dated as of May 21, 2003 (the "INDENTURE"), among the Medex
Parties and The Bank of New York, as trustee (the "TRUSTEE"), and pursuant to
the terms of that certain Exchange and Registration Rights Agreement, dated
as of May 21, 2003 (the "REGISTRATION RIGHTS AGREEMENT"), among the Medex
Parties and Lehman Brothers Inc. Capitalized terms used herein and not
otherwise defined shall have the meanings assigned to such terms in the
Registration Rights Agreement.

          This opinion letter is delivered in accordance with the requirements
of Item 601(b)(5) of Regulation S-K under the Securities Act of 1933, as amended
(the "SECURITIES ACT").

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Medex, Inc.
April 5, 2004
Page 2

          In connection with this opinion, we have examined and are familiar
with originals or copies, certified or otherwise identified to our satisfaction,
of the following documents:

          (a)     the Registration Statement;

          (b)     the Purchase Agreement;

          (c)     the Indenture;

          (d)     the Registration Rights Agreement;

          (e)     the form of the Exchange Notes; and

          (f)     the form of Exchange Guarantees.

          The agreements and other documents referred to in the foregoing
clauses (a) through (f) are collectively referred to as the "TRANSACTION
DOCUMENTS." In rendering this opinion, we have also examined originals, or
copies certified or otherwise authenticated to our satisfaction, of the
following documents and corporate records:

          (a)     A copy of resolutions adopted by the Board of Directors of
Medex, dated as of May 8, 2003, authorizing, INTER ALIA, the preparation and
filing of the Registration Statement registering the Exchange Notes and the
Exchange Guarantees, certified as true and correct as of the date hereof, by the
Secretary of Medex;

          (b)     A copy of the Second Amended Regulations, as amended, of
Medex, certified as true and correct as of the date hereof, by the Secretary of
Medex;

          (c)     A certificate from the Secretary of State of Ohio, dated
November 5, 2003, with respect to the Articles of Incorporation of Medex, as of
such date, and also certified as true and correct as of the date hereof, by the
Secretary of Medex (the "MEDEX ARTICLES");

          (d)     A certificate from the Secretary of State of Ohio, dated as
of the date hereof, with respect to the status of Medex as a corporation in
good standing under the laws of the State of Ohio;

          (e)     A copy of resolutions adopted by the Board of Directors of
MedVest, dated as of May 8, 2003, authorizing, INTER ALIA, the preparation and
filing of the Registration Statement registering the Exchange Notes and the
Exchange Guarantees, certified as true and correct as of the date hereof, by the
Secretary of MedVest;

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Medex, Inc.
April 5, 2004
Page 3


          (f)     A copy of the Regulations, as amended, of MedVest, certified
as true and correct as of the date hereof, by the Secretary of MedVest;

          (g)     A certificate from the Secretary of State of Ohio, dated
November 5, 2003, with respect to the Articles of Incorporation of MedVest, as
of such date, and also certified as true and correct as of the date hereof, by
the Secretary of MedVest (the "MEDVEST ARTICLES");

          (h)     A certificate from the Secretary of State of Ohio, dated as
of the date hereof, with respect to the status of MedVest as a corporation in
good standing under the laws of the State of Ohio;

          (i)     A copy of resolutions adopted by the Board of Directors of
Medex Cardio-Pulmonary, dated as of May 8, 2003, authorizing, INTER ALIA, the
preparation and filing of the Registration Statement registering the Exchange
Notes and the Exchange Guarantees, certified as true and correct as of the date
hereof, by the Secretary of Medex Cardio-Pulmonary;

          (j)     A copy of the Amended and Restated Regulations of Medex
Cardio-Pulmonary, certified as true and correct as of the date hereof, by the
Secretary of Medex Cardio-Pulmonary;

          (k)     A certificate from the Secretary of State of Ohio, dated
November 5, 2003, with respect to the Articles of Incorporation of Medex
Cardio-Pulmonary, as of such date, and also certified as true and correct as of
the date hereof, by the Secretary of Medex Cardio-Pulmonary (the "MEDEX
CARDIO-PULMONARY ARTICLES");

          (l)     A certificate from the Secretary of State of Ohio, dated as
of the date hereof, with respect to the status of Medex Cardio-Pulmonary as a
corporation in good standing under the laws of the State of Ohio;

          (m)     A copy of resolutions adopted by the Board of Directors of
Medex Medical, dated as of May 8, 2003, authorizing, INTER ALIA, the preparation
and filing of the Registration Statement registering the Exchange Notes and the
Exchange Guarantees, certified as true and correct as of the date hereof, by the
Secretary of Medex Medical;

          (n)     A copy of the Amended and Restated Regulations of Medex
Medical, certified as true and correct as of the date hereof, by the Secretary
of Medex Medical;

          (o)     A certificate from the Secretary of State of Ohio, dated
November 5, 2003, with respect to the Articles of Incorporation of Medex
Medical, as of such date, and also certified as true and correct as of the date
hereof, by the Secretary of Medex Medical (the "MEDEX MEDICAL ARTICLES");

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Medex, Inc.
April 5, 2004
Page 4


          (p)     A certificate from the Secretary of State of Ohio, dated as
of the date hereof, with respect to the status of Medex Medical as a
corporation in good standing under the laws of the State of Ohio;

          (q)     Such other ledgers, minutes, minute books, certificates of
officers of the Medex Parties and records certifications or representations as
to factual matters of public officials as we have deemed necessary or
appropriate for the purpose of this opinion.

          Further, all opinions expressed herein are premised upon the
assumptions, to the extent relevant to the opinions expressed, that:

          (i)     All records and documents examined by us in preparation of
this opinion are complete, authentic and accurate;

          (ii)    All documents submitted to us as copies in connection with
this opinion conform to the originals thereof;

          (iii)   No action has been taken which amends, revokes or terminates
any of the documents or records which we have reviewed;

          (iv)    All signatures contained in such records and documents are
genuine signatures of parties purporting to have signed the same; and

          (v)     All natural persons signing said documents and records had,
at the time of such signing, full legal capacity (other than natural persons
signing the Transaction Documents in their capacity as officers of the Medex
Parties) to sign and deliver said documents.

          Although we have premised our opinions contained herein upon the
assumptions stated above and have neither independently investigated nor
attempted to verify or established the accuracy of such matters, nothing is
actually known by those attorneys in our firm who have devoted substantive
attention to, or who have had active involvement in, the transactions
contemplated by the Transaction Documents, the negotiation or documentation of
such transactions, or the opinions herein rendered with respect to such
transactions, leading them to question the accuracy of such assumptions.

          We have relied upon the above-referenced documents: (a) the Medex
Articles; (b) the MedVest Articles; (c) the Medex Cardio-Pulmonary Articles; and
(d) the Medex Medical Articles (collectively, the "BUSINESS ENTITY DOCUMENTS").
Although we have neither independently investigated nor attempted to verify or
establish the accuracy or completeness of the matters set forth in the items
referred to in the Business Entity Documents, nothing has come to the attention
of those attorneys in our firm who have, as attorneys, devoted substantive
attention to the transactions contemplated by the Transaction Documents which
would lead us to question the accuracy of such matters.

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Medex, Inc.
April 5, 2004
Page 5


          Based upon and subject to the foregoing, and upon such further
investigation of law as we have deemed necessary, and subject to the
qualifications, exceptions, limitations and further assumptions set forth below,
we are of the opinion that:

          1.      The issuance and exchange of the Exchange Notes for the Old
Notes and the issuance of the Exchange Guarantees have been duly and validly
authorized by requisite corporate action on the part of the applicable Medex
Parties.

          The foregoing opinion is subject to the following further assumptions,
limitations, qualifications and exceptions:

          The opinion expressed herein is limited to the laws of the State of
Ohio and United States federal laws and we express no opinion as to the effect
or applicability of the laws of any other jurisdictions. Our opinion as to Ohio
and United States laws are further limited in that we express no opinion as to
any of the legal issues identified in clauses (a) though (r) of Section 19 of
the Legal Opinion Accord of the ABA Section of Business Law (1991).

          This opinion is limited to the matters expressly stated herein. No
implied opinion may be inferred to extend this opinion beyond the matters
expressly stated herein. We hereby consent to the reference to our firm under
the headings "Legal Matters" in the Prospectus and to the filing of this opinion
with the Commission as an exhibit to the Registration Statement. In giving such
consent, we do not concede that we are experts within the meaning of the
Securities Act or the rules and regulations thereunder or that this consent is
required by Section 7 of the Securities Act. Subject to the foregoing, this
opinion is being delivered to the Medex Parties, is intended solely for the use
of the Medex Parties, and may not be relied upon by any other person for any
purpose without the express written consent of the undersigned.


                                   Very truly yours,


                                   CALFEE, HALTER & GRISWOLD LLP