What are the common complications during hemodialysis and their interventions?

Complications During Hemodialysis and Necessary Interventions

Intradialytic Hypotension (Most Common Complication)

Intradialytic hypotension occurs in approximately 25% of all hemodialysis sessions and requires immediate intervention to prevent serious cardiovascular complications including myocardial ischemia, stroke, and vascular access thrombosis. 1

Immediate Management of Acute Hypotensive Episodes

• Stop or reduce ultrafiltration immediately to prevent further blood pressure decline 2
• Administer intravenous normal saline bolus (typically 100-250 mL) to rapidly expand plasma volume 2
• Place patient in Trendelenburg position (head down, legs elevated) to improve venous return 2
• Provide supplemental oxygen to improve tissue oxygenation and reduce symptoms 2

Prevention Strategies for Recurrent Hypotension

Dialysate modifications:

• Increase dialysate sodium concentration to 148 mEq/L to maintain vascular stability, particularly early in the session 2
• Reduce dialysate temperature from 37°C to 34-35°C to increase peripheral vasoconstriction and cardiac output 2
• Switch from acetate-containing to bicarbonate-containing dialysate to prevent inappropriate decreases in total vascular resistance 2

Pharmacological prevention:

• Administer midodrine (oral α1-adrenergic agonist) 30 minutes before dialysis initiation to prevent hypotension 2
• Review and adjust antihypertensive medications taken before dialysis, as these frequently contribute to intradialytic hypotension 2

Ultrafiltration adjustments:

• Slow the ultrafiltration rate by extending treatment time when possible 2
• Reevaluate the patient's estimated dry weight, as hypotension may indicate it is set too low 2

High-Risk Patient Populations

Patients at highest risk for intradialytic hypotension include: 1

• Diabetic patients with autonomic dysfunction
• Elderly patients (≥65 years)
• Those with pre-dialysis systolic blood pressure <100 mm Hg
• Patients with cardiovascular disease
• Those with severe anemia or hypoalbuminemia

Infection-Related Complications

Catheter-Related Bloodstream Infections

Catheter-related bloodstream infections carry an 8.5 times higher risk compared to arteriovenous fistulas and require strict adherence to infection prevention protocols. 1

Prevention measures:

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

Water Quality-Related Infections

Bacterial or endotoxin contamination of dialysis water can cause pyrogenic reactions ranging from chills and fever to septicemia with severe hypotension and shock. 1

• Perform monthly cultures and endotoxin analysis of water and dialysate as a proactive strategy 1
• Notify the medical director immediately if bacterial or endotoxin levels exceed action levels to determine if it is safe to continue dialyzing 1

Vascular Access Complications

Limb Ischemia

All patients, particularly diabetics and elderly patients, must be monitored for limb ischemia following arteriovenous access construction, as this can lead to tissue loss if not recognized emergently. 1

Monitoring protocol:

• Assess subjectively for coldness, numbness, tingling, and impaired motor function not limited by postoperative pain 1
• Assess objectively for skin temperature, gross sensation, movement, and distal arterial pulses compared to the contralateral side 1
• Refer emergently to vascular access surgeon if new findings suggestive of ischemia develop 1

Access Hemorrhage

• Apply direct pressure immediately to control bleeding from needle dislodgement or access site 3
• Avoid trauma to vessel intima during all access procedures 1

Cardiovascular Emergencies During Dialysis

Acute Dyspnea

Sudden onset dyspnea during hemodialysis most commonly results from myocardial ischemia, fluid overload, or pulmonary embolism and requires immediate assessment. 4

Immediate diagnostic approach:

• Assess vital signs immediately, including oxygen saturation 4
• Obtain 12-lead ECG to evaluate for ischemia or arrhythmias 4
• Examine for signs of fluid overload (crackles, elevated jugular venous pressure) 4
• Order chest X-ray to identify pulmonary edema, infiltrates, or pneumothorax 4

Management based on etiology:

• For suspected cardiac ischemia: obtain ECG immediately and transfer to acute care setting by EMS 4
• For fluid overload: adjust ultrafiltration goals and reassess dry weight 4
• For rapid ultrafiltration-induced dyspnea: slow ultrafiltration rate 4

Fluid Overload Complications

Basilar airspace opacification and pulmonary edema in hemodialysis patients typically represent volume overload requiring adjustment of dry weight and ultrafiltration strategy. 5

Management approach:

• Perform echocardiography to measure cardiac filling pressures and volume status noninvasively 5
• Reevaluate and gently probe the prescribed target dry weight to address potential volume overload 5
• Increase ultrafiltration with every dialysis treatment while maintaining hemodynamic stability 5
• Decrease dialysate sodium concentration to 135-140 mmol/L to reduce thirst, fluid gain, and hypertension 5
• Implement strict dietary sodium restriction (typically <2g/day) to reduce interdialytic weight gain 5

Rare Life-Threatening Emergencies

While modern dialysis machines have made these complications extremely rare, staff must remain vigilant for: 6, 3

• Dialysis disequilibrium syndrome (cerebral edema from rapid solute shifts)
• Venous air embolism (requires immediate Trendelenburg positioning and 100% oxygen)
• Hemolysis (from water treatment errors or mechanical trauma)
• Major allergic reactions to dialyzer membranes or medications
• Cardiac arrest (requires immediate basic and advanced life support)

Critical Pitfalls to Avoid

• Do not use sodium profiling techniques, as they aggravate thirst and fluid gain despite theoretical benefits 5
• Avoid overly aggressive ultrafiltration, which can cause intradialytic hypotension and damage residual kidney function 5
• Be aware that increased dialysate sodium may lead to increased thirst, interdialytic weight gain, and hypertension 2
• Recognize that most hemodialysis emergencies are attributable to human error rather than equipment failure 3
• Do not allow patients to eat immediately before or during hemodialysis, as this decreases peripheral vascular resistance and promotes hypotension 2