Dialysis-associated hypotension

Background

• Most frequent complication of hemodialysis (20%-30% of treatment)

Clinical Features

• Nausea/vomiting
• Anxiety
• Dizziness
• Orthostatic hypotension
• Syncope

Differential Diagnosis

• Excessive ultrafiltration
  • > 0.35 ml/min/kg
  • >20% plasma volume
• Predialytic volume loss
  • GI losses (e.g. vomiting, diarrhea)
  • Decreased oral intake
• Intradialytic volume loss
  • Tube and hemodialyzer blood losses
• Postdialytic volume loss
  • Vascular access blood loss
• Hemorrhage
• Medication effects
  • Antihypertensives
  • Opioids
• Decreased vascular tone (sepsis)
• Cardiac dysfunction
  • LVH, ischemia, hypoxia, arrhythmia, pericardial tamponade
• Pericardial disease
  • Effusion
  • Tamponade
• Hemolysis

Dialysis Complications

• Dialysis-associated hypotension
• Dialysis disequilibrium syndrome
• Air embolism
• Missed dialysis (pulmonary edema)

Evaluation

Assess:

• Volume status (US)
• Cardiac function
• Pericardial disease
• Infection
• GI bleeding

Evaluation by HypotensionTiming

• Early in session: usually due to preexisting hypovolemia
• During the session: often due to blood loss (from tubing or filter leak)
• Near the end: usually result of excessive ultrafiltration
  • Underestimation of patient's ideal blood volume (dry weight)
  • Also consider pericardial or cardiac disease

See Also

• Dialysis complications