Majority of Routine Screening Laboratory
Examinations Prior to an Operation NOT Necessary!
Reynaldo O. Joson, MD
Chairperson
Department of Surgery
Ospital ng Maynila Medical Center
November 6, 2002
'Routine' tests are
defined as those ordered for an asymptomatic, apparently healthy individual in
the absence of any specific clinical indication except to identify conditions
undetected by clinical history and examination.
There is a
universal concern by medical insurers, hospital administrators, surgeons and
anesthesiologists on the cost-effectiveness of routine preoperative screening
investigations. Search of the medical
literature yielded papers on this topic originating from almost all countries
in the world and with publications as early as the 70s and as recent as
2002. There is NO paper that advocates
routine preoperative screening investigations.
All papers are advocating selective screening with reliance placed on
history (interview for symptoms and risk factors) and physical examination.
It is estimated
that 60% of routine screening laboratory examinations presently being done
prior to an operation as ordered by surgeons, anesthesiologists and other
specialists like the internists and pediatricians are NOT necessary based on
the following parameters:
These routine
screening laboratory examinations include complete blood count (CBC),
urinalysis, blood chemistries, blood coagulation tests (bleeding time, clotting
time, clot retraction test, prothrombin time), chest x-ray, and ECG. These tests are usually being done in
association with cardiopulmonary and pediatric clearances, which are also being
practiced routinely and are considered also NOT to be necessary.
Selective
screening is being advocated over routine screening in all types of operations
(general surgery – head and neck, breast, abdomen, and skin and soft tissue;
gynecologic surgery; pediatric surgery; orthopedic surgery; eye surgery; and
ear, nose, throat and dental surgery) and in whatever age group including
pediatric and geriatric patients.
Selective screening is advocated not only by surgeons but also by
well-informed anesthesiologists with concern on cost-effectiveness.
Selective
screening is done when data gathered from history and physical examination make
a physician strongly suspects the presence of a subclinical (non-evident)
condition or risk that may significantly change the plan of treatment or that
may interfere with the outcome of the operation. Below are some examples of situations in which screening tests
are done using a selective approach.
1. Complete blood count is done only if a
physician strongly suspects the presence of a blood disorder because of
frequent occurrence of spontaneous bruises.
2. Hemoglobin determination (part of a blood
count) is done if the patient is suspected to be pale.
3. Blood coagulation tests are done if the patient
has a history of prolonged and excessive bleeding during a previous operation
or trauma.
4. Blood sugar determination (FBS) is done
only if a physician strongly suspects the presence of diabetes mellitus.
5. Blood chemistries on kidney function
(such as BUN, creatinine) are done only if a physician strongly suspects the
presence of a kidney function problem.
6. Blood chemistries on liver function (such
as SGOT, SGPT, TP, alkaline phosphatase) are done only if a physician strongly
suspects the presence of a liver function problem.
7. Urinalysis is done only if the patient
has symptoms of urinary disturbance such as painful urination.
8. Chest x-ray is done if the patient has a
chronic cough.
9. ECG is done at age 70 and above who are
to undergo a major operation because of the high risk of cardiac problem in
this age group as borne out by scientific evidences.
In the
Philippines, there exists a similar concern which was overtly expressed in a
project conducted by the Philippine College of Surgeons in 1999 entitled “Evidence-based
clinical guidelines on preoperative evaluation in noncardiac surgery”.
Despite the time
immemorial concern, the practice of routine approach is still prevalent
worldwide, the Philippines included.
Some of the reasons cited are medicolegal protection, habit, requirement
of institution, ignorance of scientific evidences and unawareness of
cost-effective management practice.
In the
Philippines, practicing a selective approach in preoperative screening will be
accompanied by a saving of about PhP 5,000 per patient. This was extrapolated from a study in the
Ospital ng Maynila Medical Center (OMMC) in 2001 in the Operasyon Bosyo
(Operation Goiter) conducted by the hospital’s Department of Surgery. Beside the financial savings, the other
advantages of the selective approach consist of unnecessary pain from needle
prick in blood collection; radiation exposure from routine chest x-ray; false
alarms and mental anguish in cases of false-positive results; and inconvenience
of going back and forth to the physician’s clinic, laboratory, and hospital
(average of 5 times).
Knowing that
majority of the routine screening preoperative laboratory examinations are NOT
necessary and that there is a need to shift from the routine to the selective
approach, how can change be brought about?
If you are a
patient, ask your surgeon and anesthesiologist to request only tests that are
really necessary. For any test that you
are being advised to undertake, you can ask these three questions:
If the answers
to the above three questions are small, none, and none respectively, then there
is no need for the screening test.
For the medical
insurers and hospital administrators as well as chairpersons of departments of
surgery and anesthesia who are interested in instituting a shift from routine
to selective approach, there is a model of change strategy that you can adopt
or at least get some idea from.
From 2001 to
2002, a change from a routine to selective preoperative screening
investigations has been successfully effected and institutionalized in the
Department of Surgery of Ospital ng Maynila Medical Center. The change process consisted essentially of
4 chronological phases: 1) emergence of a surgeon-manager who could act as a
change facilitator using an action research method; 2) development of a shared
mission primarily between the staff of the departments of surgery and
anesthesia and secondarily together with the staff of the nonsurgical
departments and the hospital director/administrator; 3) pilot testing with
documentation to convince all parties concerned of the benefits of the change;
and 4) institutionalization of the change and constant monitoring against
back-sliding. The change is being maintained by a memorandum of agreement
between the Department of Surgery and Department of Anesthesia with
authorization from the Hospital Director.
Anybody
interested in the details of how to effect the change, please call 524-60-61 and
look for Dr. Vivian Enriquez or Dr. Rolando de Guzman.
Email: rjoson2001@yahoo.com
Website: https://ommcsurgery.tripod.com/research/preopscreenlabexams.htm