Vascular access is the circulatory site that makes the connection between the patient’s circulation and the hemodialysis machine possible. Blood is pulled out of the body by the blood pump through the vascular access. The pump will then force the blood through the dialyzer and back to the patient’s bloodstream. A needle infiltration occurs when the needle dislodges from inside the vascular access during cannulation or during the dialysis treatment itself. Cannulation is the insertion of a needle cannula into a blood vessel to drain blood or administer blood back into circulation. When the patient has an infiltration, blood may leak outside the access into the surrounding tissues. Because of this, swelling and pain may be felt around the area. While the patient’s access will continue to function, having an infiltration will cause a lot of discomfort. It may become bruised, swollen and the area may feel firm to touch. There are two basic types of vascular accesses that need to be cared for by a dialysis technician. Each of which can become infiltrated. While both have their own strengths and weaknesses, the type to be used will always be patient-dependent.
The Basic Types of Vascular Accesses
- Internal – these accesses are usually permanent, and are ideal for patients who will be on long-term hemodialysis. An Internal access is usually placed in the early stages of chronic renal failure, even before the patient needs it. This is done so it will be ready to use when the patient actually starts treatment. Internal accesses should be cared for by the dialysis technician, especially when it’s infiltrated, so they’ll last longer.
- External – these are temporary accesses placed while the internal access is still maturing. An external access may come in the form of a straight hemodialysis catheter or a cuffed and tunneled hemodialysis catheter. This type of access is usually done when the patient only needs dialysis for a short while. A dialysis technician will still need to provide proper care even if this access is used temporarily.
Internal Vascular Access
Getting a fistula or graft placed is part of preparing the patient for hemodialysis. A fistula or graft is the ideal access for dialysis. If your patient is right handed, the surgeon’s first choice is to place the access in the patient’s left arm. If he’s left handed, the right arm will be the surgeon’s first choice. However, there are instances when this will not be the case. The surgeon will always inform the patient which arm to protect. In this regard, the dialysis technician should be well aware that the designated arm should not be compromised by IV’s, needle sticks for lab work, or even checking the blood pressure. In some cases, patients may require additional studies to verify the size of their blood vessels before the placement of the access. Ultrasound mapping is typically the most effective tool a surgeon can use to plan for access. Normally, there are no needles involved when mapping is done. On the other hand, some patients may also need a venogram done. During this study, a small needle is used to inject sterile dye into the blood vessels. The surgeon and access team will decide which study is best for the patient. The placement of an internal vascular access requires a trip to the Outpatient Surgery Department. A fistula or graft will then be placed in the operating room.
The Types of Internal Vascular Accesses
- The Arterial-Venous (AV) Fistula – The AV fistula uses the patient’s native vein and artery to make a connection. A fistula is usually situated in the patient’s upper or lower arm. When the link is made, the artery’s higher pressure pushes blood into the vein. After a few months, the vein will become larger and its walls will become thicker. The blood from these vessels can then be used for dialysis. The fistula normally matures in about 4-6 weeks. When this happens, it will now be possible to insert two needles for treatment. One needle will be used to pull blood from the patient’s body through the dialysis tubing. The blood will then flow through the dialyzer, filtering it in the process. Clean blood will be returned to the patient’s body through the second needle. The AV fistula is the most popular type of internal vascular access for hemodialysis. Since it doesn’t utilize foreign material to make, it is less likely to become infected or clotted. It is also more flexible because it is made of native tissues. When well-cared for by a dialysis technician, the AV fistula will provide the patient with better dialysis, resulting to better prognoses. Unfortunately, there are still risks involved. If a fistula may not develop successfully, a graft will then be utilized.
- The Graft – A graft is highly similar to an AV fistula. It still connects artery to a vein. It is also used for dialysis in the same way as a fistula. However, what differentiates the graft is the material it uses. Unlike a fistula, a graft utilizes a thin, hollow, semi-rigid tube of a man-made material. A graft is ideal for patients with veins that can’t or didn’t develop a fistula. Grafts are usually placed in the upper or lower arm, or the upper leg of the patient. This type of access can either be straight or looped, which are literally named after their design. Since grafts are larger and more rigid than a natural vein, the dialysis technician can insert needles through them with less trouble than with a fistula. However, grafts can become infected or clotted more easily than a fistula since they are not naturally part of the patient’s body tissue. Grafts can be used in about 2 weeks after its first placement.
Simple Infiltration Care Steps for a Dialysis Technician
- “Feel” the thrill. “Hear” the bruit. The thrill is a vibration that you can palpate. It is normally continuous and soft. Assessing the thrill will confirm the direction of the blood flow in the access. Meanwhile, the bruit is a continuous, soft, and low-pitched sound that you can hear with a stethoscope. If the sound becomes discontinuous, harsh, and high-pitched, the access may be abnormally constricting.
- Assess for the signs and symptoms of a needle infiltrate or hematoma. When infiltrated, the patient’s access will be painful and/or swollen just beyond the needle cannulation site. The swelling will worsen with infusion. When left untreated by the dialysis technician, generalized pain and swelling will be present in the access extremity. As a result of the injury to the blood vessels, bruising or discoloration may present itself on the vascular access or extremity. Since the surrounding tissues will also swell, the skin over the vascular access may tighten and become shiny. Changes in arterial or venous pressures throughout treatment without a change in the blood flow may also indicate the presence of an infiltration.
- Even though the dialysis technician is primarily responsible for providing direct patient care, the registered nurse should be notified of infiltrations and/or bruising. Dialysis technicians work under the direct supervision of registered nurses.
- Ask for assistance from the licensed nurse when assessing the vascular access for the above signs and symptoms. Open communication between members of the healthcare team will accurately determine if there is localized or generalized pain and swelling. If present, the nurse will identify the location, the size, the color, and induration. An induration is an increase in the fibrous elements in tissue. It commonly results with inflammation and is marked by loss of elasticity and pliability. When the nurse is inspecting the infiltrated site, the dialysis technician may ask for the patient’s subjective description of the pain.
- Making use of a clean pen or marker, the dialysis technician may outline the border of the infiltrate or hematoma on the patient’s skin. This is basically done to easily determine the increasing size. Circumferential measurements must be recorded in the patient’s medical chart in case an enlarging deep hematoma is present.
- Localized needle infiltrates in a vein or artery may worsen during hemodialysis treatment. Once confirmed, immediately stop the machine, and remove the needle. Using a clean gloved hand and sterile gauze, the dialysis technician should apply direct pressure to the insertion site. Infiltrations can increase in size, and will cause generalized swelling or pain. To minimize its complications, apply clean, disposable cold pack to the infiltration. However, before doing so, the dialysis technician should line the patient’s skin with a clean, moisture barrier. Constantly check on the infiltrate every 5 minutes. You can also elevate the access extremity to promote better circulation. Monitor vital signs and provide the proper supportive care accordingly.
- There are instances when a localize needle infiltrate is not increasing in size or severity. If this is the case, the dialysis technician may carefully reposition the needle and continue to use it. If not possible, clamp and secure the infiltrated needle, and then recannulate away from the infiltrated needle. Subsequently, apply clean, disposable cold pack to infiltration. However, before doing so, the dialysis technician should line the patient’s skin with a clean, moisture barrier. Remove cold pack and check infiltrated site every 15 minutes for any improvements.
- When the vein is infiltrated, and it is not increasing in size or severity, the nurse may recannulate above affected site. If not possible, remove infiltrated needle and gently apply direct pressure.
- One of the roles of a dialysis technician is educating the patient about infiltration. Be ready to explain the logic behind applying cold packs to an infiltrated site 24 hours after the incident. Timing is very important. Cold packs should be on for 15 minutes and off for 15 minutes while the patient is awake. For the first 24 hours, the size of the infiltrate should be monitored every hour. If treated well, its size and severity should gradually decrease after a few hours. Warm, moist packs may be utilized by the patient after 24 hours. However, excessive heat or heating pads should never be used since they extreme temperatures dilate blood vessels, promoting bleeding.
- After the patient is treated for a vascular access hematoma, the dialysis technician should make sure that he cannulates away from the hematoma site. Continuously asses for any changes in access or hematoma during treatment.
- Notify the physician of any changes, as needed.
- Accurately document all your findings and interventions in the patient’s medical record.