Are there situations that require acute or urgent treatment in patients undergoing chronic dialysis, despite planned sessions, and potentially involving medications like methoxy polyethylene glycol-epoetin beta (Mircera) and darbepoetin alfa (Aranesp)?

Acute and Urgent Situations Requiring Immediate Intervention in Chronic Dialysis Patients

Yes, despite the chronic and planned nature of dialysis, multiple acute life-threatening situations require urgent treatment, including acute coronary syndromes, severe hyperkalemia, uncontrolled hypertension, seizures, and urgent dialysis initiation when patients present with complications before planned access creation.

Life-Threatening Acute Complications

Acute Coronary Syndromes

• All dialysis patients presenting with acute coronary syndromes should be treated identically to the non-dialysis population, with percutaneous coronary intervention preferred over thrombolytic therapy due to increased hemorrhagic risk 1
• Dialysis patients with ST-segment elevation myocardial infarction require emergent reperfusion therapy, with PCI as the preferred treatment when available 1
• The timing of dialysis in the first 48 hours after acute coronary syndrome must account for individual risk factors including volume status, electrolyte disturbances, and bleeding potential through collaboration between nephrology and cardiology teams 1
• Mortality after acute MI in dialysis patients approaches 75% at 2 years, making aggressive acute management critical 1

Hypertensive Emergencies and Seizures

• Uncontrolled hypertension is a contraindication to initiating or continuing erythropoiesis-stimulating agents like darbepoetin alfa and methoxy polyethylene glycol-epoetin beta, requiring urgent blood pressure control before resuming therapy 2
• Hypertensive encephalopathy and seizures have been reported in CKD patients receiving darbepoetin alfa, requiring immediate dose reduction or withholding of the medication 2
• During the first several months following initiation of ESAs, patients require close monitoring for premonitory neurologic symptoms, with urgent evaluation needed for new-onset seizures or changes in seizure frequency 2
• Approximately 40% of CKD patients require initiation or intensification of antihypertensive therapy during the early phase of ESA treatment 2

Urgent Dialysis Initiation

• Dialysis-dependent patients must be transferred to functioning facilities within 48-72 hours maximum during disasters or access failures, as hospitalizations and mortality increase significantly when treatment sessions are missed 3
• Unplanned urgent dialysis initiation (starting with a hemodialysis catheter or as an inpatient) occurs in approximately 61% of new-onset hemodialysis patients and is associated with significantly increased early mortality risk (HR 2.510,95% CI 1.177-5.355) compared to planned elective starts 4
• Patients presenting as "known acute" (requiring urgent dialysis despite being known to renal services ≥4 months) have more severe anemia, lower GFR, and 90% increased odds of urgent start when they have not attended predialysis clinics 5

ESA-Related Acute Complications

Severe Allergic and Cutaneous Reactions

• Serious allergic reactions including anaphylaxis, angioedema, and bronchospasm require immediate and permanent discontinuation of darbepoetin alfa with appropriate emergency therapy 2
• Severe cutaneous reactions including Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis require immediate discontinuation of ESA therapy 2

Pure Red Cell Aplasia

• Severe anemia with low reticulocyte count developing during ESA treatment requires immediate withholding of the medication and evaluation for neutralizing antibodies to erythropoietin 2
• If PRCA is confirmed, permanently discontinue darbepoetin alfa and do not switch patients to other ESAs 2

Lack of Hemoglobin Response

• For lack or loss of hemoglobin response to ESAs, immediately initiate a search for causative factors including iron deficiency, infection, inflammation, and bleeding 2
• The most common cause of incomplete response to epoetin is iron deficiency, requiring urgent iron status evaluation and supplementation 6

Dialysis Access Emergencies

Vascular Access Complications

• Arteriovenous graft thrombosis occurs in approximately 5% of patients and requires urgent intervention to restore access function 2
• Vascular access complications occur in 8% of dialysis patients and may require emergency procedures to maintain dialysis capability 2
• Patients receiving ESAs may require increased anticoagulation with heparin to prevent clotting of the extracorporeal circuit during hemodialysis 2

Disaster and Crisis Situations

Emergency Dialysis Management

• During disasters, dialysis patients require strict fluid restriction protocols (typically 500-1000 mL per day depending on residual urine output) when treatment access is unavailable 3
• Potassium-binding resins (e.g., sodium polystyrene sulfonate) must be provided to dialysis patients to prevent life-threatening hyperkalemia during treatment gaps 3
• Patients must receive education on the renal emergency diet emphasizing fluid and potassium restriction, as they may go several days without dialysis during relocation 3

Critical Pitfalls to Avoid

• Never continue ESA therapy in patients with uncontrolled hypertension, as this is an absolute contraindication that increases risk of hypertensive encephalopathy and seizures 2
• Delaying patient relocation beyond 72 hours for dialysis-dependent patients significantly increases hospitalization and mortality risk 3
• Failing to recognize acute coronary syndromes promptly in dialysis patients leads to the extremely poor 75% two-year mortality rate, as these patients often receive inadequate post-MI treatment 1
• Inadequate medication stockpiling (less than 7 days supply) results in dangerous treatment gaps during emergencies, as pharmacy access may be impossible for 1-2 weeks 3
• Overlooking iron deficiency as the most common cause of ESA non-response delays appropriate treatment and prolongs anemia 6, 2