What are the acute complications of hemodialysis and how are they managed?

Acute Complications of Hemodialysis

Intradialytic Hypotension

Intradialytic hypotension is the most common acute complication, occurring in 15-50% of hemodialysis treatments, and requires immediate intervention as it is associated with myocardial ischemia, stroke, vascular access thrombosis, and increased mortality. 1, 2, 3

Immediate Management

• Stop or reduce ultrafiltration immediately to prevent further blood pressure decline 3
• Administer intravenous normal saline bolus (100-250 mL) to rapidly expand plasma volume 3
• Place patient in Trendelenburg position (head down, legs elevated) to improve venous return 3
• Provide supplemental oxygen to improve tissue oxygenation and reduce symptoms 1, 3

Prevention Strategies

• Avoid excessive ultrafiltration by limiting ultrafiltration rate to <13 mL/kg/hour 1, 4
• Increase dialysate sodium concentration to 148 mEq/L to maintain vascular stability, particularly early in the session 1, 3
• Reduce dialysate temperature from 37°C to 34-35°C to increase peripheral vasoconstriction and cardiac output 1, 3
• Switch from acetate to bicarbonate-buffered dialysate to prevent inappropriate decreases in total vascular resistance 1, 3
• Administer midodrine 30 minutes before dialysis to prevent hypotension 1, 3
• Review and adjust antihypertensive medications taken before dialysis 3

High-Risk Patients

Patients at highest risk include diabetics with autonomic dysfunction, elderly patients (≥65 years), those with pre-dialysis systolic blood pressure <100 mm Hg, patients with cardiovascular disease, and those with severe anemia or hypoalbuminemia. 3

Muscle Cramps

Muscle cramps are a leading cause of treatment discomfort and premature termination, occurring in approximately 70% of patients who terminate dialysis early for medical reasons. 1, 2

Management Approaches

• Avoid excessive ultrafiltration 1, 2
• Slow the ultrafiltration rate 1, 2
• Increase dialysate sodium concentration 1, 2
• Switch to bicarbonate-buffered dialysate 1, 2
• Perform isolated ultrafiltration when appropriate 1

Catheter-Related Bloodstream Infections

Catheter-related bloodstream infections carry an 8.5 times higher risk compared to arteriovenous fistulas and represent a critical acute complication requiring strict prevention protocols. 2, 3

Prevention Protocol

• Perform hand hygiene before all catheter manipulations 3
• Disinfect catheter hubs with antiseptic (soak for 3-5 minutes in povidone-iodine, then allow to dry) when accessing or disconnecting 3
• Use alcohol-based chlorhexidine at the catheter exit site during dressing changes 3
• Both patient and staff must wear surgical masks during all catheter procedures that access the bloodstream 1, 3
• Apply dry gauze dressings with povidone-iodine and mupirocin ointment at the exit site, especially in patients with nasal Staphylococcus aureus carriage 1, 3

Treatment Requirements

• Catheter removal is mandatory when tunnel tract involvement is present 2
• Three weeks of systemic antibiotic therapy are required 2
• New permanent access should not be placed until cultures have been negative for at least 48 hours after cessation of antibiotic therapy 2

Vascular Access Hemorrhage

Vascular access hemorrhage, particularly from needle dislodgement or pseudoaneurysm rupture, can be life-threatening and requires immediate recognition and intervention. 2, 5, 6

Immediate Management

• Apply direct pressure immediately to the bleeding site
• Assess for signs of hypovolemic shock (tachycardia, hypotension, altered mental status)
• Activate emergency medical services if hemorrhage is severe or uncontrolled
• Avoid needle insertion into pseudoaneurysm areas due to hemorrhage risk 2

Pseudoaneurysm Management

Surgical resection and interposition graft placement are required when pseudoaneurysms are rapidly expanding, exceed twice the graft diameter, threaten overlying skin viability, or are infected. 2

Dialysis Disequilibrium Syndrome

Dialysis disequilibrium syndrome is a potentially life-threatening neurological complication that occurs primarily in patients initiating dialysis with severe uremia (BUN >175 mg/dL). 5, 6

Clinical Presentation

• Headache, nausea, vomiting
• Restlessness, confusion
• Seizures, coma (in severe cases)

Prevention Strategy

• Reduce initial dialysis intensity in high-risk patients (first-time dialysis, severe uremia)
• Target Kt/V of 0.9-1.0 for initial treatments rather than full dose
• Shorten treatment time to 2-3 hours initially
• Consider prophylactic mannitol in very high-risk patients

Air Embolism

Venous air embolism is a rare but potentially fatal complication that can occur from disconnection of venous lines or improper priming of the dialysis circuit. 5, 6

Immediate Management

• Clamp venous line immediately to prevent further air entry
• Place patient in left lateral decubitus position with head down (Durant maneuver) to trap air in right ventricle
• Administer 100% oxygen via non-rebreather mask
• Activate emergency medical services for potential hyperbaric oxygen therapy
• Do not attempt to aspirate air from central lines unless specifically trained

Prevention

• Ensure proper priming of dialysis circuit before initiating treatment
• Use air detectors and automatic clamps on all dialysis machines
• Secure all connections and inspect regularly during treatment

Hemolysis

Acute hemolysis during dialysis is a medical emergency that can result from dialysate contamination, overheated dialysate, or mechanical trauma to red blood cells. 5, 6

Clinical Recognition

• Cherry-red blood in venous line (pathognomonic sign)
• Chest pain, dyspnea
• Hemoglobinuria (dark or red urine)
• Sudden onset of back pain

Immediate Management

• Stop dialysis immediately and do not return blood to patient
• Obtain blood samples for plasma-free hemoglobin, potassium, LDH
• Monitor for hyperkalemia and treat aggressively if present
• Maintain high urine output with IV fluids to prevent acute tubular necrosis
• Investigate cause immediately (check dialysate temperature, water treatment system, mechanical issues)

Dialyzer Reactions

Dialyzer reactions range from mild (Type A) to severe anaphylactic (Type B) reactions and require immediate recognition and treatment. 6

Type A Reactions (Mild)

• Chest tightness, back pain
• Pruritus, urticaria
• Continue dialysis with close monitoring
• Administer antihistamines as needed

Type B Reactions (Severe/Anaphylactic)

• Sudden onset within minutes of starting dialysis
• Severe dyspnea, bronchospasm
• Hypotension, cardiovascular collapse
• Stop dialysis immediately and do not return blood
• Administer epinephrine 0.3-0.5 mg IM immediately
• Provide airway support and 100% oxygen
• Administer IV fluids for hypotension
• Switch to synthetic dialyzer membranes for future treatments

Cardiac Arrhythmias and Acute Coronary Syndromes

Cardiac events during dialysis are common due to electrolyte shifts, volume changes, and the high prevalence of cardiovascular disease in dialysis patients. 1, 6

Immediate Assessment

• Obtain 12-lead ECG immediately for any chest pain, dyspnea, or palpitations 3
• Check potassium level emergently as hyperkalemia is a common cause of arrhythmias
• Assess for signs of myocardial ischemia (ST changes, troponin elevation)

Management of Acute Coronary Syndrome

• Treat dialysis patients with ACS as in the non-dialysis population, with attention to drug clearances 1
• Emergent PCI is preferred over thrombolytic therapy due to increased hemorrhagic risk 1
• Timing of dialysis in the first 48 hours after ACS should consider volume status, electrolyte disturbances, and bleeding potential 1
• Dialysis prescriptions should be adjusted to maximize benefits while reducing risk of hypotension during this vulnerable period 1

Acute Stroke During Dialysis

Hemodialysis induces a significant reduction in global and regional cerebral blood flow, and intradialytic hemodynamic instability is associated with ischemic white matter changes and cognitive dysfunction. 1

Immediate Management

• Activate stroke protocol immediately for any neurological symptoms
• Do not withhold thrombolysis in otherwise-eligible dialysis patients, including those on hemodialysis with normal PTT 1
• Thrombectomy should not be withheld in suitable candidates despite limited data in dialysis patients 1

Dialysis Considerations in Acute Stroke

• Avoid intermittent hemodialysis immediately after acute stroke when possible, as it may increase intracranial pressure due to osmotic shifts 1
• If dialysis is necessary, use slower ultrafiltration rates and avoid rapid urea reduction 1
• Minimize systemic anticoagulation to avoid exacerbating hemorrhage 1
• Monitor blood pressure carefully to maintain cerebral perfusion 1

Critical Pitfalls to Avoid

• Do not use sodium profiling techniques, as they aggravate thirst and fluid gain 3
• Do not allow patients to eat immediately before or during hemodialysis, as this decreases peripheral vascular resistance and promotes hypotension 3
• Avoid overly aggressive ultrafiltration, which can cause intradialytic hypotension and damage residual kidney function 3
• Never attempt to return blood to patient if hemolysis or severe dialyzer reaction is suspected 6
• Do not delay emergency interventions for life-threatening complications to complete the dialysis session 7, 5