Ischemia and Hypoxia During Dialysis

Primary Mechanisms of Ischemia/Hypoxia

Intradialytic hypotension is the dominant cause of ischemia during dialysis, occurring in approximately 25% of all hemodialysis sessions and directly predisposing to coronary and cerebral ischemic events through hypoperfusion of vital organs, according to the American Journal of Kidney Diseases 1, 2
The American Journal of Kidney Diseases defines intradialytic hypotension as a decrease in systolic blood pressure by ≥20 mm Hg or mean arterial pressure by ≥10 mm Hg, accompanied by symptoms including abdominal discomfort, nausea, muscle cramps, dizziness, or anxiety 1, 2
Intradialytic hypotension can lead to cardiac ischemic events from reduced coronary perfusion, cerebral ischemic events from inadequate brain perfusion, mesenteric venous infarction from splanchnic hypoperfusion, and cardiac dysrhythmias that further compromise cardiac output, as reported by the American Journal of Kidney Diseases 1, 2

The American Journal of Kidney Diseases identifies diabetic CKD patients with autonomic dysfunction, elderly patients ≥65 years with reduced physiologic reserve, patients with pre-dialysis systolic BP ≤100 mm Hg, anephric patients, and those on long-term dialysis as being at substantially increased risk for ischemia/hypoxia during dialysis 1, 2
Patients with severe anemia limiting oxygen-carrying capacity, poor nutritional status and hypoalbuminemia, and those requiring high-volume ultrafiltration (>3-4% body weight per session) are also at increased risk, according to the American Journal of Kidney Diseases 1, 2

The American Journal of Kidney Diseases is not the source of this information, however Praxis Medical Insights reports that dynamic electrolyte fluctuations during dialysis create a dysrhythmogenic state that persists for 4-5 hours post-dialysis, triggering arrhythmias that compromise cardiac output and tissue perfusion 4, 5
Key electrolyte disturbances include potassium shifts causing ventricular dysrhythmias, calcium fluctuations triggering cardiac rhythm disturbances, and magnesium depletion contributing to refractory arrhythmias, as reported by Praxis Medical Insights 4, 5