Hemodialysis is the most common form of dialysis, one that has been in use for nearly a half-century. It takes advantage of a machine that can remove a high volume of blood from the body, dialyze the blood, and return the blood to the body. For most patients, this requires reporting to a dialysis center on a regular basis for care.
Hemodialysis is a safe and well-established treatment. It has become a more efficient therapy, and its side effects have been greatly reduced in recent decades.
Team and Patient Commitment to Highly Organized Routine
The treatment is a very important aspect of a dialysis patient’s life and weekly schedule, because for most patients the treatment requires coming to a dialysis center several times a week for a few hours. Such clinics are often busy treatment environments but ones that become familiar to patients. The team at dialysis centers usually includes a nephrologist, dialysis nurse, dialysis technician, dietitian and social worker. Patients recline in a treatment chair and may sleep, read, watch television, socialize, make phone calls or otherwise relax as their dialysis proceeds, with blood removed from through one line and returned through another.
Hemodialysis is a significant commitment by the patient to health, functionality, and survival, as it typically requires a visit to the dialysis center for three to five hours, three times per week. A newer approach is shorter dialysis sessions, six times a week. (This “daily dialysis” has not yet gained coverage from the government, which currently reimburses for only three dialysis sessions per week.)
Requires Surgical Step First
Dialysis is not a simple procedure and requires a coordinated team effort to deliver well. The specialized staff of nurses and technicians at a dialysis center, under the medical directorship of a physician who is usually a nephrologist, is trained to provide the treatment.
To properly receive hemodialysis, patients must undergo a surgical procedure to allow dialysis access to a location of significant blood flow in the circulatory system. This permits a higher volume of blood removal and replacement than is possible through a typical intravenous line. The dialysis catheter used for this purpose must access large blood vessels, and may need to established and stabilized in advance of using it. The surgery to create access is typically minor and can be provided on an outpatient basis.
The three primary types of dialysis access are:
AV Fistula. To make an arteriovenous (AV) fistula (or AVF), a surgeon joins an artery with vein, for example in the arm, to create a fast, high-volume stretch of blood flow that has a strong arterial feed with strong venous drainage. Near this point, where flow is returning quickly into venous circulation, the dialysis team can remove blood to the dialysis machine and then return it by a separate line just downstream in the same vein. While the opening between arterial and venous blood flow that permits this may take some to mature and stabilize for use, an AV fistula is the preferred method of access in dialysis because of less chance of complications, the strong blood flow that it provides and the long-lasting access it offers.
Catheter. The surgeon places these double-tubed lines into a large vein (usually the vena cava). Sometimes called a central venous line or central catheter, this access permits a single catheter to withdraw blood in one direction, send it through the dialysis process and return it back into the venous flow through the tube’s other line. The catheter protrudes from the skin at the site that surgeon inserts it, usually in a vein in the neck or a vein in the thigh, and provides access without the need for any additional punctures or needles.
For a tunneled catheter, the surgeon advances the catheter some distance under the skin before accessing the vein, so that the point of entry into the circulation is contained further within the body. This reduces the chance of serious infection at the site of the vein. A tunneled catheter is best if the catheter must remain in place for at least a few weeks.
Catheter access has the advantage of not requiring needle sticks each time it is accessed. However, this approach brings the risk of infection through the skin-entry site and the risk of obstruction of the accessed vein. Thus, dialysis catheters are usually used as a temporary or rapid measure, when dialysis is needed quickly or when it is likely to take place over only a few days, weeks or months.
Because catheters establish immediate access for dialysis, they are often used when renal failure has taken place too quickly for the treatment team to establish an AV fistula or graft. The dialysis team may take advantage of catheter access after an AV fistula has been created, while waiting for the fistula to stabilize and become useable.
Arteriovenous graft. This arrangement serves much the same function as a fistula but uses a tube (usually of a special plastic) to connect the arterial and venous circulation. The arteriovenous (AV) graft (or AVG) can be a good choice when the patient’s vessels don’t lend themselves well to creating a fistula, often because they are too small. They suffer from some of the same drawbacks, though, that catheters do.
Choice of surgical access depends on the patient and the amount of time that individual is expected to remain on dialysis. The Lourdes multidisciplinary kidney team is skilled and experienced in establishing these forms of dialysis access and educating patients on their care. Patients, for example, must maintain the cleanliness of their access sites. Working with the patient, the staff provides vigilant management of these access configurations.
Lourdes provides dialysis services in partnership with the nationally recognized DaVita, Inc. at three locations in Southern New Jersey.