Exhibit 24

                               POWER OF ATTORNEY

     Know all by these presents, that the undersigned hereby makes, constitutes
and appoints each of Scott Hutton, David Poticha and Robin Harper Cowie, or any
of them acting individually, and with full power of substitution, the
undersigned's true and lawful attorney-in-fact to:

     (1)     prepare, execute in the undersigned's name and on the undersigned's
             behalf, and submit to the U.S. Securities and Exchange Commission
             (the "SEC") a Form ID, including amendments thereto, and any other
             documents necessary or appropriate to obtain codes and passwords
             enabling the undersigned to make electronic filings with the SEC of
             reports required by Section 16(a) of the Securities Exchange Act of
             1934 or any rule or regulation of the SEC;

     (2)     execute for and on behalf of the undersigned, in the undersigned's
             capacity as an officer and/or director of Biodesix, Inc., a public
             limited company incorporated under the laws of England and Wales
             (the "Company"), Forms 3, 4, and 5, including amendments thereto,
             in accordance with Section 16(a) of the Securities Exchange Act of
             1934 and the rules and regulations thereunder;

     (3)     do and perform any and all acts for and on behalf of the
             undersigned which may be necessary or desirable to complete and
             execute any such Form 3, 4, or 5, complete and execute any
             amendment or amendments thereto, and timely file such form with the
             SEC and any stock exchange or similar authority; and

     (4)     take any other action of any type whatsoever in connection with the
             foregoing which, in the opinion of such attorney-in-fact, may be of
             benefit to, in the best interest of, or legally required by, the
             undersigned, it being understood that the documents executed by
             such attorney-in-fact on behalf of the undersigned pursuant to this
             Power of Attorney shall be in such form and shall contain such
             terms and conditions as such attorney-in-fact may approve in such
             attorney-in-fact's discretion.

     The undersigned hereby grants to each such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever requisite,
necessary, or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could do if personally present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-in-fact, or such
attorney-in-fact's substitute or substitutes, shall lawfully do or cause to be
done by virtue of this power of attorney and the rights and powers herein
granted. The undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, are not assuming,
nor is the Company assuming, any of the undersigned's responsibilities to comply
with Section 16 of the Securities Exchange Act of 1934.

     This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4, and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier (a) revoked by the undersigned in a signed writing delivered to
the foregoing attorneys-in-fact or (b) superseded by a new power of attorney
regarding the purposes outlined herein at a later date.

     IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 1st day of October, 2020.


                                             /s/ Jean Franchi
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                                                          Signature


                                             Jean Franchi
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                                                          Print Name