When the kidneys reach End-Stage Renal Disease (ESRD), they have lost nearly all their filtering ability, typically functioning at less than 15% of normal capacity. Dialysis is designed to replace the kidney’s function of removing metabolic waste products and excess fluid from the blood. Choosing not to receive dialysis means forfeiting this artificial life support, allowing toxins and fluid to accumulate unchecked. This decision initiates a rapid and predictable decline as the body’s internal chemical balance collapses.
The Onset of Uremia and Systemic Toxicity
The initial phase of decline is marked by the systemic accumulation of nitrogenous waste products, primarily urea and creatinine, a condition known as uremia. These toxins, which the failing kidneys cannot excrete, begin to poison various organ systems throughout the body. Early symptoms include profound fatigue and weakness that cannot be relieved by rest.
The gastrointestinal tract is also significantly affected by uremia. Patients commonly experience persistent nausea and vomiting, often leading to a severe loss of appetite (anorexia). A distinct metallic or foul taste, called uremic fetor, develops in the mouth due to high urea concentrations in the saliva. The toxic environment also impairs the nervous system, causing early neurological changes such as difficulty concentrating, forgetfulness, and increasing confusion.
Fluid Overload and Cardiovascular Strain
As kidney function halts, the body loses the ability to regulate water and sodium balance, causing excess fluid to be retained in the vascular system and surrounding tissues. This volume expansion results in significant edema, most noticeable as swelling in the feet, ankles, and legs. The massive increase in circulating blood volume forces the heart to work harder, leading to dangerously high blood pressure, or hypertension.
This chronic overload mechanically strains the heart muscle, often progressing to congestive heart failure. Excess fluid is forced into the air sacs of the lungs, creating pulmonary edema. This fluid accumulation in the lungs causes severe shortness of breath and a drowning sensation, particularly when lying down. Cardiovascular complications are a leading cause of death in untreated kidney failure.
Critical Electrolyte Imbalances and Acidosis
Foregoing dialysis leads to the chemical destabilization of the blood, affecting electrolytes and acid-base balance. The inability of the kidneys to excrete potassium leads to hyperkalemia, a high concentration of potassium ions in the bloodstream. Since potassium is essential for the heart muscle’s electrical signaling, excessive levels disrupt the normal rhythm. This disruption causes cardiac arrhythmias, which can rapidly degenerate into ventricular fibrillation and sudden cardiac arrest.
Another severe chemical imbalance is metabolic acidosis, where the blood becomes excessively acidic because the kidneys cannot remove acid waste products like sulfuric and phosphoric acid. This intense acidity impairs the function of the heart muscle, diminishing its contractile strength and worsening existing heart failure. The body attempts to compensate by breathing faster and deeper (Kussmaul respiration) to expel carbon dioxide and temporarily raise the blood pH. The combination of hyperkalemia and uncompensated acidosis places the heart at constant risk of failure.
The Final Stages and Timeline of Decline
The timeline for decline without dialysis ranges from a few days to several weeks, depending on the patient’s residual kidney function and fluid intake restrictions. As systemic toxicity and fluid overload intensify, neurological symptoms progress to uremic encephalopathy. This severe disorder is characterized by increased drowsiness, tremors, and involuntary muscle twitching.
In the final hours or days, neurological deterioration culminates in seizures, followed by stupor and deep coma. For patients who choose to refuse or withdraw from dialysis, often referred to as Conservative Kidney Management (CKM), palliative care focuses on managing symptoms like pain, nausea, and shortness of breath to maintain comfort. Death typically results from the combined effects of overwhelming fluid on the lungs and an irreversible cardiac event caused by electrolyte imbalance.