AV graft) is used to determine if the flow can support the hemodialysis prescription and if the access is developing a clinically significant stenosis
Ultrasound Dilution Technology
Transonic Transit- Time ultrasound (TTU) flow measurement through sterile tubing is the gold standard for blood flow verification. Transonic ultrasound dilution access measurement by the ‘Krivitski Method’ is the recognized gold standard technology for dialysis patient access flow measurement. The Krivitski Method calls for the temporary reversal of arterial and venous blood lines at their respective needle connections to create mixing conditions conducive for an indicator dilution flow measurement when a bolus of isotonic saline is injected into the blood circuit. Classical dilution equations are used to calculate vascular access flow.
Transonic's transit-time ultrasound flow measurement (TTFM) detects bubbles that are 20% or larger of the inner diameter of the tubing. Bubble detection algorithms can be integrated with your OEM device to stop the pump when bubbles are detected or to send a message alert to the user.
Transit-time ultrasound
Transonic's Transit-time Ultrasound (TTU) flow measurement through sterile tubing is the gold standard for blood flow verification, and has the capability of detecting bubbles that are 20% or larger of the inner diameter of the tubing being used. Wide beam ultrasonic illumination of transit-time ultrasound flowsensors measure the velocity of fluid across the entire vessel lumen to derive volume flow in mL/min or L/min., and in the process can register the presence of bubbles.
Provides proactive cardiac index tracking helping avoid cardiac collapse
Ultrasound Dilution Technology
Ultrasound Dilution Tethodology (UDT), pioneered by Nikolai Krivistki PhD, DSc, uses body temperature saline, an innocuous indicator, injected into a patientís peripheral vascular access. The indicator is injected into the venous line, travels through the heart and lungs and returns via the arterial system where a Flow/dilution Sensor records the diluted blood concentration. Software converts the data into conventional dilution curves. Classic Stewart-Hamilton equations are used to calculate cardiac function and central hemodynamic parameters including Cardiac Output (CO).
Provides an indicator of vascular access dysfunction in fistulas, grafts, and catheters
Ultrasound Dilution Technology
To measure vascular access recirculation, flow/dilution sensors monitor the blood's ultrasound velocity (1560-1590 m/sec). The greater the protein concentration in the blood, the faster ultrasound will travel. When a bolus of isotonic saline (velocity in blood is 1533 m/sec) is injected into the blood, the blood protein concentration is diluted. Flow/dilution sensors detect the reduced ultrasound velocity. When recirculation occurs, the saline indicator returns immediately to the arterial line where the diluted blood is detected by the arterial sensor. Flow-QC software converts the data into conventional dilution curves from which recirculation can be calculated.