Treatment of Uremic Encephalopathy
Initiate renal replacement therapy immediately when uremic encephalopathy is present, as dialysis is the definitive treatment that directly addresses the underlying accumulation of uremic toxins causing neurological dysfunction. 1, 2
Immediate Indications for Dialysis
Uremic encephalopathy is an absolute indication for urgent renal replacement therapy. 3, 2 The diagnosis is often made retrospectively when symptoms improve after dialysis or transplantation, making institution of kidney replacement therapy both diagnostic and therapeutic. 4
Start dialysis emergently when any of the following are present:
- Severe encephalopathy with altered mental status, confusion, or decreased level of consciousness 3, 1, 2
- Uremic seizures requiring immediate intervention 1
- Concurrent life-threatening complications including persistent hyperkalemia, severe metabolic acidosis, or volume overload unresponsive to diuretics 3, 2, 5
Selection of Dialysis Modality
Hemodynamically Stable Patients
Intermittent hemodialysis (IHD) should be the initial modality for most patients, as it provides superior efficiency for rapid removal of uremic toxins, urea, and electrolytes. 2 Standard IHD achieves urea clearance rates that effectively reduce uremic burden within hours. 3
Hemodynamically Unstable Patients or Those with Cerebral Edema
Continuous renal replacement therapy (CRRT) is preferred over intermittent hemodialysis for patients who are hemodynamically unstable or have cerebral edema. 1, 2 CRRT provides greater improvement in hemodynamic stability, better control of azotemia and fluid overload, and improved nutritional support compared to IHD. 3, 2
In centers without CRRT capability, long-duration daily dialysis serves as an acceptable alternative for patients with cardiovascular instability. 3
Frequency of Dialysis
Frequent (daily) dialysis is recommended initially to address the continuous presence of uremic toxins and metabolites. 3 The timing and dose of dialysis should be adjusted based on clinical response and biochemical parameters. 3
Peritoneal Dialysis
Peritoneal dialysis should be reserved only for situations where hemodialysis and CRRT are unavailable, as it has significantly lower efficiency in removing uremic solutes compared to other modalities. 3, 2
Management of Seizures
For active seizures associated with uremic encephalopathy:
- Administer anticonvulsants such as diazepam, phenytoin, or barbiturates acutely 1
- Consider levetiracetam (10 mg/kg, maximum 500 mg per dose every 12 hours) as the preferred agent due to minimal drug interactions and better tolerability in renal failure 1
- Obtain EEG monitoring to detect subclinical epileptic activity and guide ongoing treatment 1
Monitoring During Treatment
- Check electrolyte levels regularly, particularly potassium, calcium, and phosphate 1, 2
- Monitor for dialysis disequilibrium syndrome, especially during the first few hemodialysis sessions 6, 7
- Assess for improvement in neurological symptoms, which typically begin within hours of initiating adequate dialysis 4, 8
Critical Pitfalls to Avoid
Do not delay dialysis while searching for other causes of encephalopathy in patients with severe renal failure and compatible symptoms. The diagnosis of uremic encephalopathy is often confirmed by clinical improvement with dialysis. 4
Avoid aluminum-containing phosphate binders, especially in combination with citrate salts, as aluminum accumulation can cause dialysis dementia, a distinct and irreversible neurological syndrome. 1, 6
Start with low-dose dialysis in dialysis-naive patients and progressively increase the dose in subsequent sessions to prevent dialysis disequilibrium syndrome. 6, 7
If neurological symptoms do not improve after adequate dialysis and improvement in clearance, promptly search for alternative explanations such as stroke, subdural hematoma, infection, or other metabolic derangements. 4, 9, 8
Management of Precipitating Factors
Address concurrent conditions that may worsen uremic encephalopathy:
- Identify and treat infections with appropriate cultures and antimicrobial therapy 1
- Correct dehydration by assessing volume status and providing appropriate fluid resuscitation 1
- Manage gastrointestinal bleeding with endoscopy, transfusion, or vasoactive drugs as needed 1
- Monitor and correct electrolyte disturbances closely 1