Vascular access for hemodialysis:
Vascular access for hemodialysis is defined as a vascular pathway which is created for uremic patients undergoing hemodialysis. A good vascular access can provide blood flow with a rate at least 500-600 mL/min and can be maintained for 4 hours to meet the needs of hemodialysis.
Types of vascular access:
- Temporary vascular access: Before the creation of the arteriovenous fistula in patients with end-stage renal disease, a temporary catheter is placed in the neck or groin for hemodialysis, such as the catheter (central venous catheters) placed in the femoral vein or internal jugular vein.
- Mid / long-term vascular access: For patients with bad vascular condition, surgical implantation of a silicone catheter, which has a soft buckle, can be fixed in the subcutaneous tunnel to prevent the invasion of foreign bodies or bacteria, called as double-lumen catheters.
- Permanent vascular access: An arteriovenous fistula is a connection, made via surgical approach, joining an artery and vein so that arterial blood can pulse into the vein achieving venous arterialization for dialysis; however, if patients have poor vascular function, the physician will create an arteriovenous graft, where an artificial vessel is used to join the artery and vein, to be used as a future puncture site, of which such grafts are divided into two types: strip and loop.
Vascular access procedures:
- Temporary vascular access
- The dressing should be changed every two days (or if necessary), in order to keep the wound clean and dry. Observe the wound for any signs and symptoms of infection, such as purulent discharge, pain, redness/heat, and swelling.
- At the end of each dialysis, the nurse will flush the catheter with saline solution and fill the catheter with an anticoagulant (heparin) to prevent it from becoming blocked.
- Avoid kinking or pulling of the catheter, in order to maintain the catheter unobstructed.
- Pay attention to whether the catheter is clamped.
- If the wound is bleeding, applying a pressure to stop bleeding and notify the medical staff as soon as possible.
- Mid- and long-term vascular access
- Same as the nursing care of “temporary vascular access.”
- Do not clamp the clip of catheter in the double-loop part of the catheter, only in the curved part.
- Permanent vascular access
Home care of arteriovenous fistulas includes arm movements, physical therapy, water and diet control, self-assessment of fistulas, prevention of infections and smoking cessation, etc. in order to maintain the functions of fistulas, extend the service life and reduce the occurrence of obstruction.
- Keep the wound clean and dry after surgery, and observe the wound daily for signs of bleeding, inflammation, or infection.
- After the creation of the arteriovenous fistula, patients should check for the thrill and the bruit (swishing sound) every day; if no bleeding occurs after the first 24 hours of surgery, they can begin doing hand grip exercises.
- Patients with arteriovenous grafts, within two weeks after suture removal, are allowed to undergo hemodialysis in about 2 to 4 weeks; the postoperative limb will swell more easily than that of the arteriovenous fistula. Blood circulation can be promote by elevating the limb with a pillow.
Practical caring in routine:
- Mid / long-term vascular access
- Avoid the wound and catheter getting wet during bathing. Apply a wipe to clean the skin around the catheter without scratching the skin around the catheter.
- Wear loose clothing to avoid kinking or pulling on the catheter.
- Pay attention ensuring the catheter is clamped.
- Observe the wound daily whether there is swelling and pain or secretions and other signs of infection and fever.
- If the wound is bleeding, applying pressure to stop bleeding and notify the medical staff as soon as possible.
- Permanent vascular access
- Same as the nursing care of “Permanent vascular access.”
- Any treatment of the hand with the arteriovenous fistula, such as injection, blood pressure measurement, and blood extraction are forbidden.
- The hand with the arteriovenous fistula is not allowed to be used as a pillow or wear too tight jewelry for avoiding to press the fistula.
- Use a wrist brace to protect the fistula, and avoid being accidentally cutting with massive bleeding. Not too tight, so as not to compress the fistula causing obstruction.
- Daily observe the fistula for sign of redness, swelling, heat, pain or other signs of infection; palpate the fistula to assess thrill and bruit (swishing sound), if there is no indication, the fistula may be occluded, and notify medical staff as soon as possible.
- After dialysis, remove the needle and apply pressure at the injection site for at least 5-10 minutes, but not too long and not wrap too tight, otherwise may affect blood flow; one must pay attention whether or not there will be bleeding or hematoma.
- If you find pinhole hemorrhage, apply pressure to stop bleeding. However, if it is still bleeding, notify medical staff as soon as possible.
- If hematoma occurs on the puncture site, an ice pack may be applied on the first day, and a warm compress (temperature not exceeding 50℃) on the succeeding days.
- Bander, S. J., Schwab, S. J.,& Woo, K. (2017,November 20). Central catheters for acute and chronic hemodialysis access. Retrieved from https://www.uptodate.com/contents/central-catheters-for-acute-and-chronic-hemodialysis-access
- Liu,L.T.(2017). Arteriovenous Fistula: The Most Common Vascular Access of Renal Disease Patients on Long-term Hemodialysis,Taipei City Medical Journal,14(4),409-415. doi:10.6200/TCMJ.2017.14.4.01.