CPT® Code 90940

A hemodialysis access flow study, identified by CPT® Code 90940, is a diagnostic procedure aimed at assessing blood flow within vascular access points used for hemodialysis, specifically in grafts and arteriovenous (AV) fistulae. This study employs an indicator method, which is a technique that utilizes ultrasound technology to monitor blood flow dynamics. The primary objective of this procedure is to detect any abnormalities in blood flow, such as stenosis, which is a narrowing of the blood vessels that can lead to complications like graft thrombosis. Early detection of these issues is crucial as it can significantly prolong the functional lifespan of the graft and improve patient outcomes. During the procedure, trained healthcare professionals, including physicians or specialized staff, conduct the study while the patient is undergoing a routine hemodialysis session. The process involves the attachment of two ultrasound sensors to the hemodialysis tubing blood lines. One sensor is placed on the tube that carries blood from the patient’s body to the dialysis machine, while the other is positioned on the tube that returns the filtered blood back to the patient. These sensors emit ultrasound waves through the tubing wall into the bloodstream, allowing for real-time monitoring of blood flow. To enhance the accuracy of the measurements, an isotonic saline solution is injected into the bloodstream. This saline bolus serves to dilute the blood, thereby altering the ultrasound velocity, which is critical for the assessment. As the saline travels through the tubing, the sensors detect changes in the ultrasound characteristics of the blood, which are indicative of the flow dynamics. The data collected from these measurements are then analyzed to identify any potential blood flow issues, ensuring timely intervention if necessary. The entire process, including the setup, measurement, and disconnection from the monitoring device, is encompassed within the scope of this procedure.