Abdominal Aortic Aneurysm Repair
(Abdominal Aneurysm - Open Repair, AAA Repair, Triple A Repair, Abdominal Aneurysmectomy, Endovascular Aneurysm Repair, EVAR)
Abdominal aortic aneurysm (AAA) repair is a procedure used to treat an aneurysm (abnormal enlargement) of the abdominal aorta. Repair of an abdominal aortic aneurysm may be performed surgically through an open incision or in a minimally-invasive procedure called endovascular aneurysm repair (EVAR).
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An abdominal aortic aneurysm, also called AAA or triple A, is a bulging, weakened area in the wall of the aorta (the largest artery in the body) resulting in an abnormal widening or ballooning greater than 50 percent of the normal diameter (width).
The aorta extends upward from the top of the left ventricle of the heart in the chest area (ascending thoracic aorta), then curves like a candy cane (aortic arch) downward through the chest area (descending thoracic aorta) into the abdomen (abdominal aorta). The aorta delivers oxygenated blood pumped from the heart to the rest of the body.
The most common location of arterial aneurysm formation is the abdominal aorta, specifically, the segment of the abdominal aorta below the kidneys. An abdominal aneurysm located below the kidneys is called an infrarenal aneurysm. An aneurysm can be characterized by its location, shape, and cause.
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The shape of an aneurysm is described as being fusiform or saccular, which helps to identify a true aneurysm. The more common fusiform-shaped aneurysm bulges or balloons out on all sides of the aorta. A saccular-shaped aneurysm bulges or balloons out only on one side.
A pseudoaneurysm, or false aneurysm, is an enlargement of only the outer layer of the blood vessel wall. A false aneurysm may be the result of a prior surgery or trauma. Sometimes, a tear can occur on the inside layer of the vessel resulting in blood filling in between the layers of the blood vessel wall, creating a pseudoaneurysm.
The aorta is under constant pressure as blood is ejected from the heart. With each heart beat, the walls of the aorta distend (expand) and then recoil (spring back), exerting continual pressure or stress on the already weakened aneurysm wall. Therefore, there is a potential for rupture (bursting) or dissection (separation of the layers of the aortic wall) of the aorta, which may cause life-threatening hemorrhage (uncontrolled bleeding) and, potentially, death. The larger the aneurysm becomes, the greater the risk of rupture.
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Because an aneurysm may continue to increase in size, along with progressive weakening of the artery wall, surgical intervention may be needed. Preventing rupture of an aneurysm is one of the goals of therapy.
There are two approaches to abdominal aortic aneurysm repair. The standard surgical procedure for AAA repair is called the open repair. A newer procedure is the endovascular aneurysm repair (EVAR).
- abdominal aortic aneurysm open repair:
Open repair of an abdominal aortic aneurysm involves an incision of the abdomen to directly visualize the aortic aneurysm. The procedure is performed in an operating room under general anesthesia. The surgeon will make an incision in the abdomen either lengthwise from below the breastbone to just below the navel or across the abdomen and down the center. Once the abdomen is opened, the aneurysm will be repaired by the use of a long cylinder-like tube called a graft. Grafts are made of various materials, such as Dacron (textile polyester synthetic graft) or polytetrafluoroethylene (PTFE, a non-textile synthetic graft). The graft is sutured to the aorta connecting one end of the aorta at the site of the aneurysm to the other end of the aorta. Open repair remains the standard procedure for an abdominal aortic aneurysm repair.
- endovascular aneurysm repair (EVAR)
EVAR is a minimally-invasive (without a large abdominal incision) procedure performed to repair an abdominal aortic aneurysm. EVAR may be performed in an operating room, radiology department, or a catheterization laboratory. The physician may use general anesthesia or regional anesthesia (epidural or spinal anesthesia). The physician will make a small incision in each groin to visualize the femoral arteries in each leg. With the use of special endovascular instruments, along with x-ray images for guidance, a stent-graft will be inserted through the femoral artery and advanced up into the aorta to the site of the aneurysm. A stent-graft is a long cylinder-like tube made of a thin metal framework (stent), while the graft portion is made of various materials such as Dacron or polytetrafluoroethylene (PTFE) and may cover the stent. The stent helps to hold the graft in place. The stent-graft is inserted into the aorta in a collapsed position and placed at the aneurysm site. Once in place, the stent-graft will be expanded (in a spring-like fashion), attaching to the wall of the aorta to support the wall of the aorta. The aneurysm will eventually shrink down onto the stent-graft.
The physician will determine which surgical intervention is most appropriate, either open repair or EVAR.
Reasons an abdominal aortic aneurysm repair may be performed include, but are not limited to, the following:
- to prevent the risk of rupture
- to relieve symptoms
- to restore a good blood flow
- size of aneurysm greater than 5 centimeters in diameter (about two inches)
- growth rate of aneurysm of more than 0.5 centimeter (about 0.2 inch) over one year
- when risk of rupture outweighs the risk of surgery
- emergency life-threatening hemorrhage (uncontrolled bleeding)
There may be other reasons for your physician to recommend an abdominal aortic aneurysm repair.
As with any surgical procedure, complications can occur. Some possible complications may include, but are not limited to, the following:
- open repair:
- myocardial infarction (heart attack)
- irregular heart rhythms (arrhythmias)
- bleeding during or after surgery
- injury to the bowel (intestines)
- limb ischemia (loss of blood flow to legs/ feet)
- embolus (clot) to other parts of the body
- infection of the graft
- lung problems
- kidney damage
- spinal cord injury
- EVAR:
- damage to surrounding blood vessels, organs, or other structures by instruments
- kidney damage
- limb ischemia (loss of blood flow to leg/feet) from clots
- groin wound infection
- groin hematoma (large blood-filled bruise)
- bleeding
- endoleak (continual leaking of blood out of the graft and into the aneurysm sac with potential rupture)
- spinal cord injury
Patients who are allergic to or sensitive to medications, contrast dyes, iodine, shellfish, or latex should notify their physician.
There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.
- Your physician will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
- You will be asked to sign a consent form that gives permission to do the procedure. Read the form carefully and ask questions if something is not clear.
- In addition to a complete medical history, your physician may perform a physical examination to ensure you are in good health before you undergo the procedure. You may also undergo blood tests and other diagnostic tests.
- You will be asked to fast for eight hours before the procedure, generally after midnight.
- If you are pregnant or suspect that you are pregnant, you should notify your physician.
- Notify your physician if you are sensitive to or are allergic to any medications, latex, iodine, tape, contrast dyes, and anesthetic agents (local or general).
- Notify your physician of all medications (prescribed and over-the-counter) and herbal supplements that you are taking.
- Notify your physician if you have a history of bleeding disorders or if you are taking any anticoagulant (blood-thinning) medications, aspirin, or other medications that affect blood clotting. It may be necessary for you to stop these medications prior to the procedure.
- If you smoke, you should stop smoking as soon as possible prior to the procedure, in order to improve your chances for a successful recovery from surgery and to improve your overall health status.
- You may receive a sedative prior to the procedure to help you relax.
- The areas around the surgical site may be shaved.
- Based upon your medical condition, your physician may request other specific preparation.
Abdominal aortic aneurysm repair requires a stay in a hospital. Procedures may vary depending on your condition and your physician's practices.
Generally, an abdominal aortic aneurysm repair follows this process:
- You will be asked to remove any jewelry or other objects that may interfere with the procedure.
- You will be asked to remove your clothing and will be given a gown to wear.
- You will be asked to empty your bladder prior to the procedure.
- An intravenous (IV) line will be started in your arm or hand. Additional catheters will be inserted in your neck and wrist to monitor the status of your heart and blood pressure, as well as for obtaining blood samples. Alternate sites for the additional catheters include the subclavian (under the collarbone) area and the groin.
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- You will be positioned on the operating table, lying on your back.
- The anesthesiologist will continuously monitor your heart rate, blood pressure, breathing, and blood oxygen level during the surgery. Once you are sedated, a breathing tube will be inserted through your throat into your lungs and you will be connected to a ventilator, which will breathe for you during the surgery.
- A catheter will be inserted into your bladder to drain urine.
- The skin over the surgical site will be cleansed with an antiseptic solution.
- Once all the tubes and monitors are in place, the physician will make an incision (cut) down the center of the abdomen from immediately below the breastbone to below the navel or across the abdomen from underneath the left arm across to the center of the abdomen and down to below the navel.
- The physician will place a clamp on the aorta above and below the site of the aneurysm. This will temporarily interrupt the flow of blood.
- The physician will cut open the aneurysm sac and suture into place a long tube called the graft. This will connect both ends of the aorta together.
- The clamps will be removed and the physician will wrap the wall of the aneurysm around the graft, suturing the aorta back together.
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- You will be placed in a supine (on your back) position on the operating table or on a procedure table in a radiology suite.
- The anesthesiologist will continuously monitor your heart rate, blood pressure, breathing, and blood oxygen level during the surgery. Once you are sedated, a breathing tube may be inserted through your throat into your lungs and you will be connected to a ventilator, which will breathe for you during the surgery.
- The physician may choose regional anesthesia instead of general anesthesia. Regional anesthesia is medication delivered through an epidural (in the back) to numb the area to be operated on. You will receive medication to help you relax and analgesic medication for pain relief. The physician will be able to talk to you during the procedure. The physician will determine which type of anesthesia is appropriate.
- The physician will make an incision in each groin to expose the femoral arteries. Using fluoroscopy (a type of x-ray "movie" that transmits images to a TV-like monitor), the physician will insert a needle into the femoral artery through which a guidewire will be passed and advanced to the aneurysm site. The needle will be removed and a sheath slid over the guidewire.
- An aortogram (injection of contrast dye to visualize the position of the aneurysm and adjacent blood vessels) will be performed.
- The physician will use special endovascular instruments and x-ray images for guidance. A stent-graft will be inserted through the femoral artery and advanced up into the aorta to the site of the aneurysm.
- The stent-graft, in a collapsed position until after it is inserted, will be advanced up into the aorta and situated at the aneurysm site. The stent graft will be expanded (in a spring-like fashion) and attached to the wall of the aorta.
- An aortogram will be repeated to check for an endoleak (blood leaking out into the aneurysm sac) of the stent-graft.
- Once no leak has been determined, the instruments will be removed.
- The incisions will be sutured back together.
- A sterile bandage/dressing will be applied.
- After an open procedure, a tube may be inserted through your mouth or nose into your stomach to drain stomach fluids.
- You will be transferred from the operating table to a bed, then taken to the intensive care unit (ICU) or the post-anesthesia care unit (PACU).
After the procedure, you may be taken to the recovery room before being taken to the intensive care unit (ICU) to be closely monitored. Alternatively, you may be taken directly to the ICU from the operating room. You will be connected to monitors that will constantly display your electrocardiogram (ECG or EKG) tracing, blood pressure, other pressure readings, breathing rate, and your oxygen level.
You may have a tube in your throat so that breathing can be assisted with a ventilator (breathing machine) until you are stable enough to breathe on your own. As you continue to wake up from the anesthesia and start to breathe on your own, the breathing machine will be adjusted to allow you to take over more of the breathing. When you are awake enough to breathe completely on your own and you are able to cough, the breathing tube will be removed.
After the breathing tube is out, your nurse will assist you to cough and take deep breaths every two hours. This may be uncomfortable due to soreness, but it is extremely important that you do this in order to keep mucus from collecting in your lungs and possibly causing pneumonia. Your nurse will show you how to hug a pillow tightly against your chest while coughing to help ease the discomfort.
You may receive pain medication as needed, either by a nurse, through an epidural catheter, or by administering it yourself through a device connected to your intravenous line.
You may be on special IV medications to help your blood pressure and your heart, and to control any problems with bleeding. As your condition stabilizes, these medications will be gradually decreased and discontinued as your condition allows.
Once the breathing tube has been removed and your condition has stabilized, you may start liquids to drink. Your diet may be gradually advanced to more solid foods as you are able to tolerate them.
If you have a drainage tube in your stomach, you will not be able to drink or eat until the tube is removed. The drainage tube will be removed when your intestinal function has returned to normal, usually two to three days after the procedure.
When your physician determines that you are ready, you will be moved from the ICU to a post-surgical nursing unit. Your recovery will continue to progress. Your activity will be gradually increased as you get out of bed and walk around for longer periods of time. Your diet will be advanced to solid foods as tolerated.
Arrangements will be made for a follow-up visit with your physician.
You may or may not be taken to the intensive care unit (ICU); however, you may be taken to a post anesthesia care unit (PACU). You will be connected to monitors that will constantly display your electrocardiogram (ECG or EKG) tracing, blood pressure, other pressure readings, breathing rate, and your oxygen level.
You will remain in either the ICU or PACU for a designated period of time and then transferred to a regular nursing care unit.
You will be given pain medication for incisional pain or you may have had an epidural (a type of anesthesia that involves continually infusing an anesthetic medication through a thin catheter (hollow tube) into the space that surrounds the spinal cord in the lower back, causing numbness in the lower body, abdomen, and/or chest) placed during surgery which will help with postoperative pain.
Your activity will be gradually increased as you get out of bed and walk around for longer periods of time. Your diet will be advanced to solid foods as tolerated.
Arrangements will be made for a follow-up visit with your physician.
Once you are home, it will be important to keep the surgical area clean and dry. Your physician will give you specific bathing instructions. The sutures or surgical staples will be removed during a follow-up office visit, in the event they were not removed before leaving the hospital.
The surgical incision may be tender or sore for several days after an aneurysm repair procedure. Take a pain reliever for soreness as recommended by your physician.
You should not drive until your physician tells you to. Other activity restrictions may apply.
Notify your physician to report any of the following:
- fever and/or chills
- redness, swelling, or bleeding or other drainage from the incision site
- increase in pain around the incision site
Your physician may give you additional or alternate instructions after the procedure, depending on your particular situation.
The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease, or replace the professional medical advice you receive from your physician. Please consult your physician with any questions or concerns you may have regarding your condition.
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