A brachial axillary arteriovenous (AV) graft is a synthetic tube placed under the skin of the upper arm, connecting an artery and a vein. This surgical connection creates a high-flow, reliable access point for hemodialysis, a process that filters the blood when the kidneys have failed. The graft serves as a reinforced pathway, allowing the high blood flow rates necessary to effectively clean the blood during dialysis treatments.
Context: Why This Specific Graft Is Necessary
The standard recommendation for long-term dialysis access is an arteriovenous fistula, which surgically joins a patient’s native artery and vein without synthetic material. However, not all patients possess veins suitable for this procedure, often due to repeated procedures or underlying vascular disease. When native veins are too small, weak, or have been exhausted by prior access attempts, a synthetic graft becomes a necessary alternative for creating a functional access.
This decision-making process follows a general “fistula first” principle, where surgeons prioritize using the patient’s own vessels. When initial attempts at a forearm fistula fail or pre-operative mapping shows poor vein quality, a graft is considered. The brachial axillary placement uses the brachial artery and a deep vein like the axillary vein, which are larger vessels found higher up the arm. This upper-arm placement is often a later-stage option for patients who have already used and failed more distal access sites. The synthetic nature of the graft allows for quicker use compared to a fistula, which must mature for several months.
The Surgical Procedure and Initial Healing
The placement of a brachial axillary AV graft is typically performed as an outpatient procedure, meaning the patient can often go home the same day. The surgery usually takes between one to two hours, often utilizing local anesthesia with sedation, or sometimes a regional nerve block, to minimize discomfort. The surgeon makes one or two incisions in the upper arm or shoulder region to connect the prosthetic tube between the brachial artery and the axillary vein. The synthetic graft is then tunneled just beneath the skin to form a loop or a straight connection, depending on the patient’s anatomy.
Post-operatively, managing pain and swelling is a primary focus; keeping the arm elevated above heart level helps reduce this swelling. Unlike a fistula, a graft may be ready for use in as little as two to four weeks, but typically requires three to four weeks for the surrounding tissue to heal. During this initial period, the incision site must be kept clean and dry to prevent infection. Feeling a gentle vibration, known as the “thrill,” beneath the skin is an early positive sign that blood is flowing properly through the graft.
Daily Management and Proper Dialysis Access
A central aspect of living with the graft is adhering to the “limb alert” protocol, which protects the access site from damage. Patients must avoid activities that could compress or damage the graft, including:
- Allowing blood pressure cuffs, blood draws, or intravenous lines to be placed in the access arm.
- Wearing tight clothing, watches, or jewelry that could compress the graft and impede blood flow.
- Sleeping on the access arm.
- Carrying heavy objects, typically over ten pounds, to prevent trauma or clotting.
Patients should monitor the graft daily by checking for the “thrill,” a subtle buzzing sensation that confirms the graft is open and functioning. The corresponding sound, called the “bruit,” can be heard with a stethoscope and also indicates good blood flow. During dialysis treatments, proper needle insertion, or cannulation, is important to preserving the graft’s integrity. Dialysis staff must rotate the cannulation sites along the length of the graft to prevent repeated punctures in the same small area, which helps avoid weakening the graft material.
Recognizing and Addressing Potential Issues
Synthetic grafts carry a higher risk of certain complications compared to native fistulas, making patient awareness of warning signs very important. One of the most urgent issues is thrombosis, or clotting, which occurs when blood flow stops within the graft. A sudden loss of the thrill or bruit, accompanied by coolness or numbness in the arm, signals a clot and requires immediate medical attention to salvage the access.
Infection is a significant concern for grafts because the synthetic material offers a surface where bacteria can easily adhere and colonize. Signs of infection include localized redness, unusual warmth, pain, or drainage from the skin over the graft, sometimes accompanied by a fever.
Stenosis, the narrowing of the graft, often develops at the connection point to the vein due to scar tissue formation. Indicators include difficult cannulation, prolonged bleeding after dialysis, or a change in the quality of the thrill. Steal Syndrome (access-induced ischemia) occurs when blood is diverted away from the hand into the graft. This results in cold, painful fingers or hand and can lead to tissue damage if left untreated.