Exhibit 3.118

CERTIFICATE OF INCORPORATION
OF
METRO AMBULANCE SERVICE (RURAL), INC.

ARTICLE ONE
NAME

The name of the corporation is METRO AMBULANCE SERVICE (RURAL), INC. (the
"Corporation").

ARTICLE TWO
PERIOD OF DURATION

The period of duration of the Corporation is perpetual.

ARTICLE THREE
PURPOSES AND POWERS

Section 1. Purposes. The purposes for which the Corporation is organized are to
transact any and all lawful business for which corporations may be organized
under the General Corporation Law of the State of Delaware (the "GCL").

Section 2. Powers. Subject to any specific written limitations or restrictions
imposed by the GCL, by other law, or by the Certificate of Incorporation, and
solely in furtherance thereof, but not in addition to the purposes set forth in
Section 1 of this Article, the Corporation shall have and exercise all of the
powers specified in the GCL, which powers are not inconsistent with the Articles
of this Certificate.

ARTICLE FOUR
CAPITALIZATION, PREEMPTIVE RIGHTS AND VOTING

Section 1. Authorized Shares. The Corporation shall have authority to issue one
class of shares to be designated as, "Common Stock". The total number of shares
of Common Stock which the Corporation is authorized to issue is One Hundred
Thousand (100,000), all at a par value of $.01.

Section 2. Preemptive Rights. Unless otherwise determined by the Board of
Directors, no holder of shares of capital stock of the Corporation shall, as
such holder, have any right to purchase or subscribe for any capital stock which
the Corporation may issue or sell, whether or not exchangeable for any capital
stock of the Corporation, whether issued out of unissued shares authorized by
this Certificate of Incorporation as originally filed or by any amendment
thereof, or out of shares of capital stock of the Corporation acquired by it
after the issue thereof; nor unless otherwise determined by the Board of
Directors in the manner provided under the GCL, shall any holder of shares of
capital stock of the Corporation, as such holder, have any right to purchase,
acquire or subscribe for any securities which the Corporation may issue or sell
whether or not convertible into or exchangeable for shares of capital stock of
the Corporation, and



whether or not any such securities have attached or appurtenant thereto
warrants, options or other instruments which entitle the holders thereof to
purchase, acquire or subscribe for shares of capital stock.

Section 3. Voting. In the exercise of voting privileges, each holder of shares
of the capital stock of the Corporation entitled to voting rights shall be
entitled to one (1) vote for each share held in his name on the books of the
Corporation. In all elections of Directors of the Corporation, cumulative voting
is expressly prohibited. As such, each holder of shares of capital stock of the
Corporation entitled to vote at the election of Directors shall have the right
to vote, in person or by proxy, all or any portion of such shares for or against
each individual Director to be elected and shall not be entitled to vote for or
against any one Director more than the aggregate number of shares held by such
holder which are entitled to vote on the election of Directors. With respect to
any action to be taken by the Shareholders of the Corporation as to any matter,
the affirmative vote of the holders of a majority of the shares of the capital
stock of the Corporation entitled to vote thereon and represented in person or
by proxy at a meeting of the Shareholders at which a quorum is present shall be
sufficient to authorize, affirm, ratify or consent to such action. Any action
required by the GCL to be taken at any annual or special meeting of Shareholders
may be taken without a meeting, without prior notice, and without a vote, if a
consent or consents in writing, setting forth the action so taken, shall be
signed by the holder or holders of a majority of the outstanding shares of the
capital stock of the Corporation entitled to vote thereon.

ARTICLE FIVE
REGISTERED AGENT AND OFFICE

Section 1. Registered Office. The address of the registered office of the
Corporation is in the State of Delaware is The Prentice-Hall Corporation System,
Inc., 32 Loockerman Square, Suite L-100 in the City of Dover, County of Kent,
Delaware 19901-7421.

Section 2. Registered Agent. The name of the registered agent of the Corporation
at such address is The Prentice-Hall Corporation System, Inc.

ARTICLE SIX
DIRECTORS

Section 1. Board of Directors. The Board of Directors shall consist of one or
more members who need not be residents of the State of Delaware or Shareholders
of the Corporation. The number of Directors of the Corporation may from time to
time be changed in accordance with the Bylaws of the Corporation and the GCL.

Section 2. Names and Addresses. The names and addresses of the persons who are
to serve as Directors until the next annual meeting of Shareholders or until
their successors are elected and qualified, or until their earlier death,
resignation, or removal are as follows:


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                     NUMBER, STREET
NAME                 OR BUILDING                         CITY, STATE
- ----                 --------------                      -----------
                                                   
Paul M. Verrochi     67 Batterymarch Street, Suite 300   Boston, MA 02110
Dominic J. Puopolo   67 Batterymarch Street, Suite 300   Boston, MA 02110
John K. Rester       12020 Intraplex Parkway             Gulf Port, MS 39503-4602


Section 3. Limitations on Liability of Directors. No Director of the Corporation
shall be personally liable to the Corporation or its Shareholders for monetary
damages for an act or omission in the Director's capacity as a Director;
provided, however, that the foregoing provision shall not eliminate or limit the
liability of a Director to the extent a Director is found liable for (a) a
breach of the Director's duty of loyalty to the Corporation or its Shareholders,
(b) an act or omission not in good faith that constitutes a breach of duty of
the Director to the Corporation or an act or omission that involves intentional
misconduct or a knowing violation of the law, (c) a transaction from which the
Director received an improper benefit, whether or not the benefit resulted from
an action taken within the scope of the Director's office, or (d) an act or
omission for which the liability of the Director is expressly provided by an
applicable statute.

If the GCL or other applicable provision of Delaware law hereafter is amended to
authorize further elimination or limitation of the liability of Directors, then
the liability of a Director of the Corporation, in addition to the limitation on
the personal liability provided herein, shall be limited to the fullest extent
permitted by the GCL or other applicable provision of Delaware law as amended.
Any repeal or modification of this Section 3 by the Shareholders of the
Corporation shall be prospective only, and shall not adversely affect any
limitation on the personal liability of a Director of the Corporation existing
at the time of such repeal or modification.

ARTICLE SEVEN
SPECIAL POWERS OF BOARD OF DIRECTORS

In furtherance of, and not in limitation of the powers and authorities conferred
under the GCL, the Board of Directors is expressly authorized:

(1) To make, alter, amend and rescind the Bylaws of the Corporation; to fix,
adjust and maintain from time to time the amount to be reserved as working
capital; and to authorize and cause to be executed mortgages and liens upon the
real and personal property of the Corporation.

(2) From time to time, to determine whether and to what extent and at what times
and places and under what conditions and provisions the accounts and books of
the Corporation shall be maintained and made available for inspection of any
Shareholder, and no Shareholder shall have any right to inspect any account or
books or records of the Corporation, except as provided in the GCL, or
authorized by the Board of Directors.

(3) If the Bylaws so provide, to designate two or more of their number to
constitute an executive committee, which committee shall, as provided in said
resolution or in the Bylaws of the Corporation, have and exercise any or all of
the powers of the Board of Directors in the


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management of the business and affairs of the Corporation, except to the extent
that the GCL requires a particular matter to be authorized by the Board of
Directors.

ARTICLE EIGHT
ADDITIONAL POWERS IN BYLAWS

The Corporation may in its Bylaws confer powers and authorities upon the Board
of Directors in addition to the foregoing and to those expressly conferred upon
them by the GCL.

ARTICLE NINE
TRANSACTIONS WITH DIRECTORS, OFFICERS AND SHAREHOLDERS

The Officers, Directors and Shareholders holding ten percent (10%) or more of
the outstanding capital stock of the Corporation ("Insiders") may enter into
business transactions with the Corporation in which they are personally
interested without such transaction being affected or invalidated solely because
of such personal interest; provided, however, that nothing contained herein
shall relieve any Insider from liability for breach of the fiduciary duties of
an Insider or authorize any Insider to enter into any transaction with the
Corporation in which such Insider has a material interest for the purpose of
personal gain to the detriment of the Corporation.

ARTICLE TEN
INDEMNIFICATION

Section 1. Mandatory Indemnification and Advancement of Expenses. Each person
who was or is made a party or is threatened to be made a party to or is involved
in any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative, arbitrative or investigative, any appeal in
such action, suit or proceeding, and any inquiry or investigation that could
lead to such an action, suit, or proceeding ("Proceeding"), by reason of the
fact that he is or was a Director or Officer of the Corporation, or who, while a
Director of the Corporation, is or was serving at the request of the Corporation
as a director, officer, partner, venturer, proprietor, trustee, employee, agent,
or similar functionary of another corporation, partnership, joint venture, sole
proprietorship, trust, employee benefit plan or other enterprise, shall be
indemnified and held harmless by the Corporation to the fullest extent permitted
by the GCL against all judgments, penalties (including excise and similar
taxes), fines, settlements, and reasonable expenses (including attorneys' fees)
actually incurred by such person in connection with such Proceeding. Such right
shall be a contract right and shall include the right to require advancement by
the Corporation of reasonable expenses (including attorneys' fees) incurred in
defending any such Proceeding in advance of its final disposition; provided,
however, that the payment of such expenses in advance of the final disposition
of such Proceeding shall be made by the Corporation only upon delivery to the
Corporation of a written affirmation by such person of his good faith belief
that he has met the standard of conduct necessary for indemnification under the
GCL and a written undertaking, by or on behalf of such person, to repay all
amounts so advanced if it should be ultimately determined that such person has
not satisfied such requirements.


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Section 2. Nature of Indemnification. The indemnification and advancement of
expenses provided for herein shall not be deemed exclusive of any other rights
permitted by law to which a person seeking indemnification may be entitled under
any Bylaw, agreement, vote of Shareholders or disinterested Directors or
otherwise, and shall continue as to a person who has ceased to be a Director or
Officer of the Corporation and shall inure to the benefit of the heirs.
executors and administrators of such a person.

Section 3. Insurance. The Corporation shall have power to purchase and maintain
insurance or another arrangement on behalf of any person who is or was a
Director, Officer, employee or agent of the Corporation, or is or was serving at
the request of the Corporation as a Director, officer, partner, venturer,
proprietor, trustee, employee, agent, or similar functionary of another
corporation, partnership, joint venture, sole proprietorship, trust, employee
benefit plan or other enterprise against any liability asserted against him and
incurred by him in any such capacity, or arising out of his status as such,
whether or not the Corporation would have the power to indemnity him against
such liability under the provisions of this Article Ten or the GCL.

ARTICLE ELEVEN
AMENDMENT OF BYLAWS

The Shareholders of the Corporation hereby delegate to the Board of Directors
the power to adopt, alter, amend or repeal the Bylaws of the Corporation. Such
power shall be vested exclusively in the Board of Directors and shall not be
exercised by the Shareholders.

ARTICLE TWELVE
POWER TO CALL SPECIAL SHAREHOLDERS' MEETINGS

Special meetings of the Shareholders of the Corporation may be called by the
President of the Corporation, the Board of Directors or holders of not less than
ten percent (10%) of all the shares entitled to vote at the proposed special
meeting of the Shareholders.

ARTICLE THIRTEEN
AMENDMENTS

The Corporation reserves the right to amend, alter, change or repeal any
provision contained in this Certificate of Incorporation or in its Bylaws in the
manner now or hereafter prescribed by the GCL or this Certificate of
Incorporation, and all rights conferred on Shareholders herein are granted
subject to this reservation.


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ARTICLE FOURTEEN
INCORPORATOR

The name and mailing address of the Incorporator of the Corporation is as
follows:



NAME                          MAILING ADDRESS
- ----                          ---------------
                           
Lila Newberry Bradley, Esq.   3340 Peachtree Road, N.E.
                              Suite 2000,
                              Tower Place
                              Atlanta, Georgia  30326-1026


ARTICLE FIFTEEN
CAPTIONS

The captions used in this Certificate of Incorporation are for convenience only
and shall not be construed in interpreting the provisions hereof.

IN WITNESS WHEREOF, the Incorporator of the Corporation has caused this
Certificate of Incorporation to be executed on this 9th day of August, 1994.


/s/ Lila Newberry Bradley
- -----------------------------------------
Lila Newberry Bradley, Esq., Incorporator


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CERTIFICATE OF AMENDMENT
OF
CERTIFICATE OF INCORPORATION
OF
METRO AMBULANCE SERVICE (RURAL), INC.

Metro Ambulance Service (Rural), Inc., a corporation organized and existing
under and by virtue of the General Corporation Law of the State of Delaware,
DOES HEREBY CERTIFY:

FIRST: That the Board of Directors of said corporation has adopted by unanimous
written consent the following resolution:

RESOLVED: That is advisable and in the best interest of this Corporation that
Section 1 of Article 4 of the Certificate of Incorporation of this Corporation
be amended to read in its entirety as follows:

"Section 1. Authorized Shares. The Corporation shall have authority to issue one
class of shares to be designated as, "Common Stock". The total number of shares
of Common Stock which the Corporation is authorized to issue is Three Thousand
(3,000), all at a par value of $.01."

SECOND: That said amendment has been consented to and authorized by the holder
of a majority of the issued and outstanding stock entitled to vote by written
consent given in accordance with the provisions of Section 228 of the General
Corporation Law of the State of Delaware.

THIRD: That the aforesaid amendment was duly adopted in accordance with the
applicable provisions of Section 242 and 228 of the General Corporation Law of
the State of Delaware.

IN WITNESS WHEREOF, said corporation has caused this Certificate to be signed by
William E. Earl, its President, and attested by Daniel W. Alexander, its
Secretary, this 18 day of September, 1995.


/s/ William E. Earl
- -------------------------------------
President


Attested by: /s/ DW Alexander
             ------------------------
             Secretary


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CERTIFICATE OF CHANGE OF REGISTERED AGENT
AND
REGISTERED OFFICE

* * * * *

Metro Ambulance Service (Rural), Inc., a corporation organized and existing
under and by virtue of the General Corporation Law of the State of Delaware,
DOES HEREBY CERTIFY:

The present registered agent of the corporation is The Prentice-Hall Corporation
System, Inc., and the present registered office of the corporation is in the
county of New Castle.

The Board of Directors of Metro Ambulance Service (Rural), Inc., adopted the
following resolution on the 1st day of September, 1996.

Resolved, that the registered office of Metro Ambulance Service (Rural), Inc.,
in the state of Delaware be and it hereby is changed to Corporation Trust
Center, 1209 Orange Street in the City of Wilmington, County of New Castle, and
the authorization of the present registered agent of this corporation be and the
same is hereby withdrawn, and THE CORPORATION TRUST COMPANY, shall be and is
hereby constituted and appointed the registered agent of this corporation at the
address of its registered office.

IN WITNESS WHEREOF, Metro Ambulance Service (Rural), Inc. has caused this
statement to be signed by William George, its Vice President this 1st day of
September, 1996.


By /s/ William George
   -----------------------------------
   William George
   Vice President


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