Dialysis is a medical treatment that takes over the function of failing kidneys, filtering waste products and excess fluid from the blood. This process is essential for sustaining life when the kidneys can no longer perform their essential function. Dialysis helps maintain the body’s internal balance, preventing harmful substances from accumulating.
Why Dialysis Becomes Necessary
Healthy kidneys filter waste and excess fluid, balance electrolytes, and produce hormones. When kidney function severely declines, these tasks are compromised. Waste products like urea and creatinine, along with excess water, build up, leading to uremia. This severe stage of chronic kidney disease, End-Stage Renal Disease (ESRD), means kidneys function at 10 to 15 percent of normal capacity. Without intervention, toxin accumulation and fluid overload become life-threatening.
Key Medical Indicators for Initiation
The decision to start dialysis is largely guided by specific medical criteria. A primary indicator is the Glomerular Filtration Rate (GFR), which measures how effectively the kidneys are filtering blood. Dialysis is considered when the GFR falls below 15 mL/min/1.73m², signifying a severe reduction in kidney function, though some guidelines suggest initiation around 6-9 mL/min/1.73m².
Beyond GFR, the presence and severity of symptoms and complications are important. Patients with advanced kidney failure may experience overwhelming fatigue, nausea, vomiting, and a metallic taste in their mouth. Swelling in the hands, feet, or face, along with shortness of breath due to fluid buildup in the lungs, are common signs. Neurological symptoms, such as difficulty concentrating or muscle twitching, indicate that waste products are affecting the brain.
Laboratory abnormalities support the need for dialysis. High levels of potassium, phosphorus, and acid in the blood indicate that the kidneys can no longer regulate these substances. These imbalances can lead to serious health issues, including abnormal heart rhythms. The combination of a low GFR, significant symptoms, and electrolyte disturbances signals that the kidneys are no longer able to sustain bodily functions.
Beyond the Numbers: Patient-Centered Factors
The decision to begin dialysis extends beyond laboratory results and is a collaborative process involving the patient, their family, and the healthcare team. A patient’s overall health and quality of life are important considerations. This includes evaluating how symptoms like fatigue and fluid retention impact their daily activities, energy levels, and general well-being.
Patient preferences and values play an important role, ensuring the treatment plan aligns with their understanding of their condition and their personal goals. Other existing health conditions, known as comorbidities, can influence the timing and type of dialysis chosen. Preparation for dialysis is also important, often involving a surgical procedure to create a vascular access point, such as an arteriovenous (AV) fistula or graft, well in advance for healing and maturation.
Implications of Timing
The timing of dialysis initiation carries important implications for patient outcomes. Delaying dialysis when medical indicators and symptoms are severe can lead to serious complications. These include fluid overload, high potassium levels, and uremic encephalopathy, a brain dysfunction caused by toxin buildup. Such delays often result in emergency dialysis initiation, which is not ideal compared to a planned start.
Conversely, studies have shown that starting dialysis too early, particularly in asymptomatic individuals, may not offer survival benefits and could be associated with increased risks. Some research suggests that starting dialysis at higher GFRs may be linked to a higher risk of mortality. The goal is an individualized approach, balancing medical necessity with the patient’s well-being, aiming for a planned rather than an urgent initiation.