Automatic Frequent Measurements of Plasma Sodium, Potassium, Total Carbon Dioxide, Urea Nitrogen, and Other Values During Hemodialysis

Customizing acute and chronic hemodialysis treatments by tailoring the prescription can occur by knowing the patient’s electrolyte and acid-base status at any given moment. Point-of-care (POC) testing using whole blood samples can provide laboratory results of sodium, potassium, chloride, bicarbonate, glucose, calcium, phosphorus, blood urea nitrogen, creatinine, pH, partial pressure of carbon dioxide, oxygen, and lactate. The impact of dialysis on these values will impact patient outcomes and quality of life. Besides knowing the laboratory results, one can calculate the anion gap and osmolar gap to treat patients with disorders such as diabetic ketoacidosis and alcohol poisoning, respectively. We describe a new technology for obtaining blood samples from the hemodialysis arterial line and using a POC device installed in the dialysis machine to perform electrolyte and blood gas measurements, and inform the clinician promptly of possible prescription adjustments to meet the needs of the patient requiring acute or chronic hemodialysis. Besides the obvious benefits, we highlight some pitfalls associated with using whole blood versus serum samples, and arterial versus venous blood samples.