Dialysis is a medical procedure that filters waste products, excess salts, and fluid from the blood, assuming the function of failing kidneys. This treatment is necessary for end-stage renal disease (ESRD) when the kidneys can no longer adequately perform this cleansing task. Starting dialysis involves significant adjustment, requiring preparation, understanding the treatment process, and changes to daily routines. This guide provides a clear overview of what new patients can expect as they transition to this life-sustaining therapy.
Understanding the Types of Dialysis
Patients facing kidney failure typically choose between two primary methods: hemodialysis (HD) and peritoneal dialysis (PD). HD involves drawing the blood out of the body, circulating it through a specialized filter (dialyzer), and then returning the cleansed blood. This process requires a machine and is often performed at a medical facility three times per week, with each session lasting about four hours.
PD uses the body’s internal lining of the abdomen, the peritoneal membrane, as the filter. A cleansing fluid, dialysate, is introduced into the abdominal cavity through a catheter. Waste products pass into the dialysate, which is later drained and replaced.
The choice often depends on personal lifestyle, as PD offers greater flexibility and is generally performed at home. PD is a continuous therapy, performed daily, either manually (CAPD) or overnight using an automated machine (APD). HD is intermittent, requiring stricter control over fluid and diet between sessions than PD.
Preparing the Body for Treatment
Preparing the body requires a surgical procedure to create a reliable access point for treatment, regardless of the chosen modality. For hemodialysis, the preferred method is an arteriovenous (AV) fistula, a surgical connection between an artery and a vein, usually in the arm. This connection increases blood flow and strengthens the vein wall to withstand repeated needle insertions.
Fistula preparation requires maturation time for the vein to enlarge and strengthen, often taking between four weeks and several months before use. If the patient’s vessels are unsuitable, a synthetic arteriovenous graft may be implanted. Grafts generally require a shorter maturation period, sometimes two to six weeks.
For peritoneal dialysis, a soft peritoneal catheter must be surgically placed into the abdomen. This catheter serves as the conduit for the dialysate fluid. Surgeons typically place this device ten to fourteen days before routine exchanges begin to allow the site to heal.
What Happens During a Dialysis Session
In-center hemodialysis begins after the access site is cleaned and two needles are inserted into the fistula or graft. One needle draws blood toward the dialyzer, and the other returns the cleaned blood to the body. The blood circulates through the machine, where the dialyzer performs cleansing and excess fluid is removed via ultrafiltration.
During the four-hour treatment, nurses monitor blood pressure and heart rate, as rapid fluid removal can cause sudden drops (hypotension). Common side effects include muscle cramps, nausea, or dizziness, managed by adjusting the rate of fluid removal. After the session, needles are removed, and pressure is applied to stop bleeding.
Peritoneal dialysis exchange involves three phases: fill, dwell, and drain. During the fill phase, dialysate flows into the abdominal cavity via the catheter, taking ten to twenty minutes. The dwell time (typically four to six hours) allows waste products to transfer into the fluid.
The drain phase removes the used dialysate into a collection bag. While the exchange is not painful, some patients feel fullness or bloating while the fluid dwells. Automated cycler users perform multiple exchanges overnight, remaining connected for eight to twelve hours while sleeping.
Managing Daily Life and Restrictions
Integrating dialysis requires careful adherence to long-term lifestyle adjustments, particularly concerning diet and fluid intake. A renal dietitian guides patients in modifying food choices to manage the accumulation of minerals and waste products. Most dialysis patients require a higher intake of protein to replace losses that occur during filtering.
Controlling mineral levels is important. This includes limiting phosphorus intake, which can lead to weakened bones and skin itching. Patients must also restrict foods high in potassium, as elevated levels affect heart rhythm. Sodium restriction is equally important because salt causes thirst, leading to excessive fluid intake and potential fluid overload.
Fluid management is a constant concern, especially for those on intermittent hemodialysis, who may be restricted to less than a quart daily. Tracking all liquids consumed prevents fluid buildup, which can cause swelling, shortness of breath, and strain on the heart. Patients learn their target “dry weight,” which is their body weight without excess fluid retained between sessions.
Medication adherence is routine for managing kidney failure. Many patients take phosphate binders with meals to absorb phosphorus from food, preventing it from entering the bloodstream. Since failing kidneys produce less erythropoietin, many patients receive Erythropoiesis-Stimulating Agents (ESAs) to treat anemia, often accompanied by iron supplements.
Scheduling revolves around the chosen modality. HD requires keeping three four-hour slots per week open. PD patients must perform exchanges in a clean environment and maintain a set schedule, but this offers greater flexibility for work and travel. Successful management relies on consistent communication with the healthcare team and commitment to these adjustments.