From the Guidelines
Transient bilateral vision loss post dialysis is most likely caused by dialysis-associated reductions in blood pressure, serum potassium, and serum phosphorus, as well as changes in other electrolytes and proteins, which may lead to a "perfect storm" of stress on the brain and cardiovascular system. This is supported by the 2015 update of the KDOQI clinical practice guideline for hemodialysis adequacy 1. The exact mechanism is not fully understood, but it is thought to be related to the removal of low-molecular-weight hormones, vitamins, and other vital molecules during dialysis, as well as the exposure of the blood to a large foreign surface for several hours.
Some possible causes of transient bilateral vision loss post dialysis include:
- Dialysis-associated reductions in blood pressure, which can lead to decreased blood flow to the brain and eyes
- Electrolyte imbalances, such as changes in serum potassium and phosphorus levels, which can affect nerve function and muscle contractions
- Changes in other electrolytes and proteins, which can contribute to a "perfect storm" of stress on the brain and cardiovascular system
- Uremic toxins, which can accumulate and damage the optic nerve
To manage transient bilateral vision loss post dialysis, it is essential to:
- Stabilize blood pressure and correct electrolyte imbalances
- Optimize dialysis parameters, such as gradual ultrafiltration rates and sodium profiling, to minimize rapid fluid shifts
- Evaluate patients promptly by an ophthalmologist and neurologist
- Monitor pre-dialysis and post-dialysis weights, blood pressure readings, and electrolyte levels to prevent recurrence
- Adjust the dialysis prescription as needed to prevent repeated episodes, as suggested by the KDOQI clinical practice guideline for hemodialysis adequacy 1.
From the Research
Causes of Transient Bilateral Vision Loss Post Dialysis
- Transient bilateral vision loss post dialysis can be caused by hypotension-induced blindness, as reported in patients on renal dialysis who suffered severe longstanding hypotension with bilateral non-arteritic anterior ischaemic optic neuropathy 2.
- Another possible cause is ischemic optic neuropathy, which is a risk factor associated with blood pressure decrease, a common complication of hemodialysis 3.
- However, it is worth noting that not all cases of vision loss in dialysis patients are directly related to hypotension or ischemic optic neuropathy, as other factors such as crystal deposition in end-stage kidney disease treated with peritoneal dialysis can also lead to catastrophic retinal vascular occlusion and vision loss 4.
- The relationship between blood pressure control and vision loss is complex, and while some studies suggest that controlling blood pressure is crucial in preventing vision loss 2, 3, others focus on the importance of blood pressure management in preventing cardiovascular and renal outcomes in patients with hypertension and type 2 diabetes 5, 6.