<PAGE>
                                                                EXHIBIT 10.21(b)

                             FIRST AMENDMENT TO THE
                   HCA SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN


         This is the First Amendment to the HCA Supplemental Executive
Retirement Plan, as effective July 1, 2001 (the "Plan"). Under Section 8.1 of
the Plan, the Board of Directors of HCA Inc. has the right to amend the Plan in
the following particulars. Accordingly, the Board of Directors hereby amends the
Plan in the following particulars effective as of October 1, 2003.

                                       1.

         The following sentence is added to Section 3.1, relating to Benefit
Amount, to follow the last sentence thereof:

         Unless the Participant voluntarily pays his share of the FICA tax due
         and payable with respect to his Benefit, the Participant's Benefit
         shall be reduced utilizing Actuarial Factors (unless a lump-sum is
         paid, in which case the lump-sum will be directly offset) by the FICA
         tax payment made by the Employer on the Participant's behalf.

                                       2.

         In order to change the death benefit provisions with respect to
individuals who die prior to retirement, Section 5.1 of the Plan is amended to
read as follows:

         5.1 DEATH. In the event of the death of a married Participant prior to
         Retirement, but after attainment of age 55, an annuity shall be
         supplied for the benefit of the Participant's surviving spouse with
         payments beginning as soon a administratively feasible following death
         which shall provide the surviving spouse with payments for life equal
         to the 100% survivor portion of a joint and 100% survivor annuity which
         could have been provided (assuming eligibility conditions met) for the
         Participant and spouse with the Participant's Benefit as determined on
         the day immediately preceding the date of the Participant's death. The
         Early Retirement factors supplied in Section 3.1(b)(1) shall be
         utilized to calculate the Benefit that would exist if a single life
         annuity was payable. (Such Benefit amount shall then be utilized to
         calculate the actual survivor annuity Benefit.) In the event of death
         of a married Participant prior to age 55, an annuity shall be supplied
         for the Participant's surviving spouse with payments beginning as soon
         as administratively feasible following death which shall supply the
         surviving spouse with payments for life equal to the 100% survivor
         portion of a joint and 100% survivor annuity which could have been
         provided (assuming eligibility conditions were met) for the Participant
         and spouse with the Participant's Benefit as determined on the day
         immediately preceding the date of the Participant's death. The Early



<PAGE>

         Retirement factors supplied in Section 3.1(b)(1) shall be utilized to
         calculate the Benefit at age 55, and such age 55 Benefit shall then be
         reduced by Actuarial Factors to the date of death, to calculate the
         Benefit that would exist if a single life annuity was payable. (Such
         Benefit amount shall then be utilized to calculate the actual survivor
         annuity Benefit.) Should a married Participant die after Retirement,
         but before his Benefit payments begin and before a benefits election
         form has been received by the Committee, then an annuity shall be
         supplied for the benefit of the Participant's surviving spouse with
         payments beginning as soon as administratively feasible following death
         which shall supply the surviving spouse with payments for life equal to
         the survivor portion of a joint and 100% survivor annuity which could
         have been provided for the Participant and spouse with the
         Participant's Benefit as determined on the day immediately preceding
         the date of the Participant's death. Notwithstanding the preceding
         provisions of this Section 5.1, at its discretion, the Committee may
         pay any surviving spouse's foregoing Benefits or the remainder thereof
         in the form of a lump-sum distribution in cash. In such a case, the
         Actuarial Factors shall be utilized to calculate the lump-sum amount.
         No death benefits shall exist whatsoever for a single Participant.

                                       3.

All provisions of the Plan not inconsistent herewith are hereby ratified and
confirmed.


<PAGE>

<TABLE>
<CAPTION>
EFFECTIVE DATE OF SCHEDULE:  NOVEMBER 1, 2003                                          SCHEDULE A
--------------------------------------------------------------------------------------------------------------------

                                           ACCRUAL RATE    EMPLOYEE HOLDING TITLE
           POSITION                         PERCENTAGE             IN 2003            INITIAL PARTICIPATION DATE
---------------------------------------------------------------------------------------------------------------------
<S>                                        <C>             <C>                        <C>
       CEO                                     2.4         Jack O. Bovender, Jr.                 07/01/01
---------------------------------------------------------------------------------------------------------------------
       President & COO                         2.4         Richard M. Bracken                    07/01/01
---------------------------------------------------------------------------------------------------------------------
       Eastern Group President                 2.4         Jay Grinney                           07/01/01
---------------------------------------------------------------------------------------------------------------------
       Eastern Group CFO                       2.2         Bill B. Rutherford                    07/01/01
---------------------------------------------------------------------------------------------------------------------
       Western Group President                 2.4         Samuel N. Hazen                       07/01/01
---------------------------------------------------------------------------------------------------------------------
WESTERN GROUP CFO                              2.2         Richard J. Shallcross                 07/01/01
---------------------------------------------------------------------------------------------------------------------
       President - Financial                   2.2         Beverly B. Wallace                    07/01/01
           Services Group
---------------------------------------------------------------------------------------------------------------------
       President - Ambulatory                  2.2         Greg Roth                             07/01/01
           Surgery Division
---------------------------------------------------------------------------------------------------------------------
CFO AMBULATORY SURGERY DIVISION                2.2         Don Liedtke                           07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP & General Counsel                   2.2         Robert A. Waterman                    07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP & CIO                               2.2         Noel B. Williams                      07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP & Controller                        2.2         R. Milton Johnson                     07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP Finance & Treasurer                 2.2         David G. Anderson                     07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP, Development                        2.2         V. Carl George                        07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP, Ethics, Compliance & Corp.         2.2         Alan P. Yuspeh                        07/01/01
           Responsibility
---------------------------------------------------------------------------------------------------------------------
       SVP, Government Programs                2.2         Patricia T. Lindler                   07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP, Human Resources                    2.2         John M. Steele                        11/01/03
---------------------------------------------------------------------------------------------------------------------
       SVP, Internal Audit &                   2.2         Joseph N. Steakley                    07/01/01
           Consulting Services
---------------------------------------------------------------------------------------------------------------------
       SVP, Investor Relations &               2.2         Victor L. Campbell                    07/01/01
           Public Relations
---------------------------------------------------------------------------------------------------------------------
       SVP, Operations Administration          2.2         A. Bruce Moore, Jr.                   07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP, Operations Finance                 2.2         Rosalyn S. Elton                      07/01/01
---------------------------------------------------------------------------------------------------------------------
       SVP, Contracts &                        2.2         James A. Fitzgerald                   07/01/01
           Operations Support
---------------------------------------------------------------------------------------------------------------------
       Medical Director & SVP Quality          2.2         Frank M. Houser                       07/01/01
---------------------------------------------------------------------------------------------------------------------
</TABLE>



<PAGE>
<TABLE>
<S>                                            <C>         <C>                                   <C>
---------------------------------------------------------------------------------------------------------------------
DIVISION PRESIDENT - FINANCIAL SERVICES        2.2         Eric Ward                             04/01/03
---------------------------------------------------------------------------------------------------------------------
       Division President -                    2.2         Jeffrey A. Dorsey                     07/01/01
           Continental Division
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - CONTINENTAL                     2.2         Gregory J. D'Argonne                  07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - Southeast          2.2         Charles R. Evans                      07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - SOUTHEAST                       2.2         Jeffrey T. Crudele                    07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - East               2.2         Stephen L. Royal                      04/01/03
           Florida
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - EAST FLORIDA                    2.2         James M. Petkas                       07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President -                    2.2         John Kausch                           07/01/01
           International Operations
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - INTERNATIONAL OPERATIONS        2.2         Michael Neeb                          07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - Delta              2.2         Maurice L. Lagarde                    07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - DELTA                           2.2         Michael A. Reese                      07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - Far West           2.2         Thomas J. May                         07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - FAR WEST                        2.2         Donald W. Stinnett                    07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - West               2.2         J. Daniel Miller                      07/01/01
           Florida
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - WEST FLORIDA                    2.2         R. Samuel Hankins                     07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - North Texas        2.2         William D. Poteet, III                07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - NORTH TEXAS                     2.2         Thomas O. Corley                      07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - Mid America        2.2         William P. Rutledge                   07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - MID AMERICA                     2.2         Russell K. Harms                      07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION PRESIDENT - NORTH FLORIDA             2.2         Charles J. Hall                       07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - NORTH FLORIDA                   2.2         Kim M. Lelli                          07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President - Gulf Coast         2.2         Michael D. Snow                       07/01/01
---------------------------------------------------------------------------------------------------------------------
</TABLE>


<PAGE>
<TABLE>
<S>                                            <C>         <C>                                   <C>
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - GULF COAST                      2.2         Jeffry R. Anthony                     07/01/01
---------------------------------------------------------------------------------------------------------------------
       Division President -Central             2.2         Marilyn B. Tavenner                   07/01/01
           Atlantic
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - CENTRAL ATLANTIC                2.2         V. Lynn Strader                       07/01/01
---------------------------------------------------------------------------------------------------------------------
DIVISION PRESIDENT - MIDWEST                   2.2         Bryan Rogers                          04/01/03
---------------------------------------------------------------------------------------------------------------------
DIVISION CFO - MIDWEST                         2.2         Clifton Mills                         04/01/03
---------------------------------------------------------------------------------------------------------------------
INACTIVE PARTICIPANTS
---------------------------------------------------------------------------------------------------------------------
       Division President - North              2.2         James W. Slack, Jr.                   07/01/01
           Florida                                         (retired 5/31/03)
---------------------------------------------------------------------------------------------------------------------
       SVP, Human Resources                    2.2         Philip R. Patton                      07/01/01
                                                           (deceased 10/23/03)
                                                           Susan Patton (Spouse)                 11/1/03
---------------------------------------------------------------------------------------------------------------------
</TABLE>