The kidneys regulate fluid volume, filter waste products, and balance electrolytes. End-Stage Kidney Disease (ESKD) occurs when the kidneys function at less than 10 to 15% of their normal capacity. Without intervention like dialysis or transplantation, ESKD is fatal. When treatment is withdrawn, the body’s inability to manage its internal environment leads to a predictable series of physiological failures. This process involves the toxic buildup of substances and the failure of fluid regulation. This article explains the mechanisms that lead to death and how compassionate care manages the final days.
The Underlying Physiological Causes of Death
The fundamental cause of death is the body’s inability to excrete waste products and regulate chemical balances. The retention of nitrogenous waste, known as uremia, is a major factor. Uremic toxins, such as urea and creatinine, poison the central nervous system, causing a progressive decline in brain function.
The failure to eliminate fluid and sodium results in volume overload, straining the cardiovascular system. This excess fluid backs up into the lungs, causing pulmonary edema. Pulmonary edema is a life-threatening complication in ESKD, leading to severe respiratory distress and failure.
An imbalance of electrolytes is the most immediate and common cause of sudden death. The kidneys lose the ability to excrete potassium, leading to hyperkalemia (dangerously high concentration in the blood). Elevated potassium interferes with the electrical signaling of the heart muscle, disrupting the heart’s rhythm and resulting in a fatal cardiac arrhythmia.
Recognizing the Signs of End-Stage Decline
The physiological failures translate into a set of observable, progressive symptoms during the patient’s final days. Neurological changes are common due to the toxic effects of uremia on the nervous system, ranging from confusion and delirium to a deepening state of drowsiness that progresses to coma.
Fluid overload manifests as severe shortness of breath, medically termed dyspnea, as the lungs fill with fluid. This is coupled with generalized swelling, or edema, particularly noticeable in the legs, ankles, and feet. Gastrointestinal symptoms are also prominent, including persistent nausea, vomiting, and a severe loss of appetite.
Patients often report intense, generalized itching, known as uremic pruritus, caused by the deposition of waste products in the skin. Extreme fatigue and muscle weakness become overwhelming, leading to the patient becoming bed-bound. The decline in kidney function is marked by oliguria (very little urine output) or anuria (no urine output), a clear sign that the body’s filtering system has ceased to function.
Palliative Care and Comfort Measures
The focus of care during the final stages of kidney failure shifts to providing comfort and managing distressing symptoms. Managing pain and anxiety is a primary goal, requiring careful selection of medications because the body cannot clear drug metabolites. Opioids like hydromorphone or fentanyl are preferred over morphine, whose metabolites can accumulate and cause increased confusion in kidney failure patients.
Respiratory distress caused by fluid overload is managed with positioning, such as elevating the head, and sometimes with low-dose opioids to ease the sensation of breathlessness. Aggressive interventions to remove fluid are avoided in this non-curative setting, and the goal is simply to make the patient’s breathing easier. Anticholinergic drugs like glycopyrrolate may be used to dry up upper respiratory secretions, which can cause a “death rattle” sound distressing to families.
Emotional and psychological support for both the patient and the family is a central component of palliative care. The care team provides reassurance and education to the family, explaining that symptoms like noisy breathing do not necessarily indicate patient distress. The final hours are managed by reducing unnecessary medical monitoring and focusing on a peaceful environment, ensuring the patient is comfortable and supported until death.