|
Patient
Advice and Information
Abdominal Aortic
Aneurysm
by Dr Panayiotopoulos, Consultant Vascular and General Surgeon
Essex.
1. What is an aneurysm?
An aneurysm is a stretching of a weakened artery which
balloons out rather like a worn motorcar tyre. The wall of the
artery becomes thinned by loss of its elastic tissue, resulting in
ballooning of the artery, making it likely to burst. The most
common artery to be affected is the aorta, which is the main
artery in the abdomen
[stomach], supplying with blood the legs and all the abdominal
organs.
|
|
· The
normal transverse diameter of the aorta is about 15mm.
· When
it is twice that size or greater than 29mm it is
considered to be an aneurysm.
· Most
of the patients are men over the age of 60 years.
· Smoking
and increased blood pressure is known to increase the risk.
·
However, small aneurysms do not represent a serious risk. |
The rupture [burst] of an
aortic aneurysm is a common cause of sudden death [4% of such
deaths in men] while the risk of such a death peaks up in men aged
70-79 years, approaching 2% of all deaths.
Very few patients survive rupture without surgery;
death rate in the community is estimated to be around 90%
[6,000-10,000 deaths in England and Wales annually]. Of those
patients who reach the hospital, death rate is on average 60%
[35-75%].
2. How is abdominal aortic aneurysm
detected?
Most aneurysms [60%] do not cause any symptoms,
therefore they are diagnosed coincidentally when the patients
are examined for another problem, or if they have a scan for a
different reason [i.e. kidney trouble or gallstones for example].
Occasionally the patient may be aware of a pulsation in the
abdomen. As the aneurysm stretches, it may cause symptoms, the
most common of which is backache as it pushes the spine. It
may also cause ankle swelling [by compressing the main vein in the
abdomen], shooting pain in the groin by compressing nerves, or
tenderness in the abdomen in cases of inflammation.
 
If an aneurysm
is suspected, your GP will refer you to a specialist Vascular
Surgeon for advice; either your GP or specialist will order an
ultrasound scan. Ultrasound scanning of the abdomen is a
painless outpatient test that only takes a few minutes to do. It is
used to decide whether an aneurysm is present and to measure its
exact size.
For large aneurysm and when
surgery is considered, your specialist may request a CT-scan,
a special X-ray that gives more accurate information compared to the
ultrasound
3. Who is at risk?
It is known that men over the age of 60,
younger men with a brother or father who has had an aneurysm
or men with other arterial disease [high blood pressure,
angina and peripheral vascular disease] are at higher risk. In some
areas of the country people at increased risk of having an abdominal
aortic aneurysm are being offered screening by ultrasound
scan. It was thus found that the annual incidence of aortic
aneurysms was 5.4% for all aneurysms and 2.3% for aneurysms greater
than 4cm in diameter.
4. Do I need surgery?
Not all aneurysms need an operation.
The risk of rupture and therefore the need for repair, depends on
the size of the aneurysm. The risk of rupture is small for
aneurysms less than 4cm in diameter, and extremely great for
those above 5.5cm, with 43% of the patients dying from rupture
within 2 years. For aneurysms between 4 -5.5cm, the risk of rupture
is 15-25% in 5 years [6% per annum]. Consequently, for large
aneurysms [more than 5cms in diameter], is probably safer to have an
operation to repair it than to leave it alone. This protects the
aorta from rupture.
Smaller aneurysms are usually observed by repeat
ultrasound scanning
at 6-12 monthly intervals, in case they enlarge and become
dangerous. Average enlargement is about 0.5cm per year, so surgery
may be required in the future at later stage. If the aneurysm
expands rapidly, is probably safer to have surgery to repair it.
Your specialist Vascular Surgeon will give you a clear explanation
of the options in your case.
5. What does surgery involve?
The operation is done through a long up and down
incision in your abdomen.
Current
surgical treatment involves the insertion of a new lining into
the aorta [like the inner tube of a tyre] made of a very strong
plastic material called Dacron. This will last up to 20 years
or more.
 
A new technique
has developed in the last 5 years that involves percutaneous
insertion of stent-grafts by means of proper radiological
control to exclude the aneurysm. The technique is still at its
infancy, and is feasible in less than one quarter of the cases.
6. Is surgery
successful?
If aortic aneurysms are repaired before they rupture,
there is a high overall chance of successful repair and return to
normal life expectancy. However, you should discuss the risks of
surgery in your particular case with your surgeon. The overall
death rate for planned repair is less than
5%.
7. How can I help myself?
There is nothing you can do about the aneurysm.
However, improving your general health by taking regular
exercise, losing weight and stopping smoking is helpful, even if you
do not need an operation at present. Controlling the high blood
pressure may delay the expansion rate of the aneurysm and may
thus reduce slightly the risk of rupture.
Abdominal Aortic Aneurysm Repair
1. Why do I need the operation?
Because the main artery [aorta] in your abdomen has
stretched and weakened forming an aneurysm which is either large or
is causing symptoms, therefore the risk of rupture is extremely
high [43% at two years]; if it bursts, the risk of dying from it
is extremely high [60%]. Therefore, the risk of rupture outweighs
the risk of surgery. This operation is to repair the stretched
section so that it will not burst.
2. Before your operation
You will usually be admitted into hospital one or two
days before your operation. You will also be asked to attend a
pre-admission clinic about a week earlier in order to allow time for
tests required to ensure you are fit for the operation. These tests
may include ultrasound and CT scans of the abdomen [if not
done earlier] or x-rays of the arteries [arteriogram]. Special
scans of your heart to check that it is working properly may
also be needed.
3. Coming into hospital
Please bring with you all the medications that you
are currently taking. You will be admitted to your bed by one of the
nurses who will also note down your personal details in your nursing
records. Prior to surgery you will undergo a number of
investigations, if these have not been performed previously,
including a heart tracing, a chest x-ray and blood tests. You will
be visited by the surgical team who will perform your operation as
well as the doctor who will give you the anaesthetic. If you have
any questions regarding the operation please ask the doctors. You
will be started on injections of heparin which will continue
throughout your stay in hospital. This stops blood clots forming in
the veins of your legs.
4. The operation
You will be taken into the anaesthetic room and from
there to theatres. As well as being put to sleep, you may have a
small tube placed at your back [epidural] to help with pain relief
following surgery. Whilst you are asleep, tubes will also be
inserted into your bladder to drain your urine, into your stomach
[via your nose] to stop you feeling sick and into a vein in your
neck for blood pressure measurements and administration of fluids
following surgery.
You will have a long cut up and down your
abdomen and very rarely you may have a small cut in one or both
groins. The aorta and particularly its swollen area will be replaced
by an artificial blood vessel made from plastic [Dacron]. The
wounds are usually closed with a stitch under the skin that
dissolves by itself.
5. After the operation
You will usually be taken to an intensive care
or high dependency unit following your operation in order to be able
to monitor your progress closely. It is sometimes necessary for you
to remain on a breathing machine for a period after the
operation but you will be taken off this as soon as possible.
Following this sort of surgery the bowel stops
working for a while and you will be given all the fluids you require
in a drip until your bowel can cope with fluids by mouth. One
of the first signs that the bowel is working is when you pass wind
down below.
A blood transfusion may also be required.
The nurses and doctors will try and keep you free
of pain by giving pain killers by injection via the tube in your
back or by a machine that you are able to control by pressing a
button.
As the days pass and you improve the various tubes
will be removed and you will return to the normal ward until you
are fit enough to go home. This is usually 7-10 days after
your operation. The physiotherapist will visit you before and
after the operation to help you with your walking and with your
breathing to prevent you developing a chest infection.
6. Going home
.
As
dissolvable stitches have been used, these do not need to be
removed. However, the stitch takes a long time to dissolve and if it
comes to the surface it may be removed with a tweezers.
.
You
will feel tired for many weeks after the operation but this
should gradually improve as time goes by. Regular exercise such as
short walk combined with periods of rest is recommended for the
first few weeks after surgery, followed by a gradual return to
your normal activity.
.
Driving: It will be safe to drive when
you are able to move without pain and perform an emergency car stop.
.
Bathing: You may bathe or shower as
normal, but do not soak in a bath until the wound is fully healed
[i.e. no scabs as these may become soggy]
.
Work: You should be able to return to
work within 1-3 months following your operation. If in doubt, please
ask your doctor.
.
Lifting: You should avoid heavy
lifting or straining for 4 weeks after the operation.
.
Medications: You will usually be sent
home on a small dose of aspirin if you were not already
taking it. This is to make the blood less sticky. If you are unable
to tolerate aspirin an alternative drug may be prescribed. You
should also continue taking your regular medications.
.
Sexual activity: You may resume sexual
activity when you feel comfortable to do so.
.
Follow-up:
Your vascular Surgeon will see you in the outpatients’ clinic 6
weeks after discharge. In most cases there is no need for further
follow-up appointments.
7. Complications
.
Chest infections can occur following
this type of surgery, particularly in smokers, and may require
treatment with antibiotics and physiotherapy.
.
Wound problems: Slight discomfort
and twinges of pain in your wound is normal for several weeks
following surgery, but wounds sometimes become infected and
these can usually be successfully treated with antibiotics. Also the
wound in your groin [if you have one] may fill with a fluid called
lymph that may discharge between the stitches, but this
usually settles down with time. [Occasionally, further minor surgery
may be required].
.
As
with any major operation such as this, there is a small risk of
you having a medical complication such as a heart attack, but
the doctors and nurses will try to prevent these complications and
to deal with them rapidly if they occur.
.
Occasionally the bowel is slow to start working again but
this requires patience and fluids will be provided in a drip until
your bowels come back to normal.
. Sexual
activity may be affected due to nerves
in your abdomen being injured during the operation. This usually
causes a failure of ejaculation. Problems with erection are due to
preexisting vascular disease and insufficient blood supply to the
deep pelvis.
. The
death rate for planned elective surgery is between
3-5%.
8. What can I do to help myself?
If you were previously a smoker you must make a
sincere and determined effort to stop completely. Continued smoking
will cause further damage to your arteries and your graft is more
likely to stop working.
Every effort should be made to control your blood
pressure as hypertension causes further damage to your arteries.
General health measures such as reducing weight, a low fat diet and
regular exercise are also important.
Return to top of page.
Please note:
A written referral from a general practitioner is helpful but is not essentially required in order to make an appointment to see a consultant specialist. |
