Dialysate Composition and Chemistry Flashcards

What is the purpose of bicarbonate in hemodialysis dialysate?

Answer: To correct metabolic acidosis by providing a buffer that crosses into the patient's blood

Bicarbonate in dialysate diffuses across the membrane into the blood, replacing bicarbonate lost to ESRD-associated metabolic acidosis and restoring acid-base balance.

Why is glucose often added to hemodialysis dialysate?

Answer: To prevent hypoglycemia during treatment and reduce glucose loss across the membrane

Adding glucose (typically 100–200 mg/dL) to dialysate helps prevent intradialytic hypoglycemia and reduces net glucose loss, particularly in diabetic patients.

What is the typical sodium concentration range in hemodialysis dialysate?

Answer: 135–145 mEq/L

Dialysate sodium is typically maintained at 135–145 mEq/L to approximate normal plasma sodium and avoid hypo- or hypernatremia during treatment.

Which ion in dialysate is primarily responsible for controlling dialysate conductivity?

Answer: Sodium

Sodium is present in the highest concentration in dialysate and contributes most to overall ionic conductivity, making it the primary determinant of conductivity readings.

What happens if dialysate calcium is set too high for a patient?

Answer: Hypercalcemia, potentially causing cardiac arrhythmias, vascular calcification, and soft tissue deposits

Excess calcium transferred from dialysate to blood causes hypercalcemia, which can trigger arrhythmias, worsen vascular calcification, and cause soft tissue mineral deposits.

The potassium concentration in hemodialysis dialysate is typically set at:

Answer: 1–4 mEq/L, individualized to the patient's pre-dialysis serum potassium

Dialysate potassium is individualized based on pre-treatment serum levels to safely remove excess potassium without causing dangerous hypokalemia.