Why is normal saline used to rinse and prime the extracorporeal circuit prior to treatment?

Normal saline is utilized to rinse and prime the extracorporeal circuit primarily to remove air. When setting up the dialysis machine and circuit, any trapped air can lead to complications, such as air embolism, which poses significant risks to patient safety. Priming the circuit with normal saline helps to displace air bubbles, ensuring that the circuit is filled with fluid, thus preventing any air from entering the patient's bloodstream during dialysis.

While other concerns like bacteria, carbon filings, or residual chlorine are important in the context of overall dialysis safety and circuit maintenance, they are not the primary reason for using normal saline in this specific procedure. Normal saline serves the crucial role of facilitating a smooth and safe connection between the dialysis machine and the patient by eliminating air from the circuit. This practice supports the overall efficacy of the treatment while protecting the patient from potential harm.