System and method for controlling venous air recovery in a portable dialysis system
The present specification discloses a portable dialysis system comprising a mechanism that allows the user to accurately position an air bubble in a venous line, so that it can be safely removed. When an air bubble is detected, the system automatically runs the blood pump in a direction such that the air bubble is placed close to the extraction point on the venous line, from where it can safely be removed using a needleless syringe.
1. A portable dialysis system for conducting hemodialysis on a patient, the system comprising:
a dialyzer;
an arterial blood line for carrying blood from the patient;
a blood pump for drawing blood from said arterial line and pumping it to the dialyzer;
a venous blood line for carrying purified blood from said dialyzer to said patient;
a pinch clamp to prevent air in said venous line from being returned to the patient;
an air bubble detector positioned in said venous blood line for detecting an air bubble arising in said venous blood line, wherein the air bubble detector is positioned within a range of 10 to 20 cm upstream of said pinch clamp and within a range of 20 to 40 cm downstream of said dialyzer;
an extraction port located within a range of 10 to 20 cm upstream of said air bubble detector and within a range of 10 to 20 cm downstream of said dialyzer in the venous blood line, said extraction port being adapted to remove the said air bubble; and
a controller in communication with said air bubble detector and said blood pump, said controller configured to cause said blood pump to run in a reverse direction back toward said dialyzer when an air bubble is detected, such that the air bubble is moved upstream towards the extraction port.
2. The system of claim 1 , wherein the blood pump is run in a reverse direction for a specified time period of the order of 2-15 seconds.
3. The system of claim 1 further comprising a display with a Graphical User Interface (GUI), wherein said Graphical User Interface is in communication with said controller.
4. The system of claim 3 , wherein the GUI is configured to issue an alarm as soon as an air bubble is detected.
5. The system of claim 4 , wherein the GUI is configured to provide an option to the user to discontinue hemodialysis treatment when an air bubble is detected.
6. The system of claim 3 , wherein when an air bubble is detected, the GUI is configured to display instructions for a user to remove the air bubble.
7. The system of claim 3 , wherein the GUI is configured to display a plurality of navigation buttons, wherein said plurality of navigation buttons are configured to enable a user to adjust a position of the air bubble for extraction from said extraction port.
8. The system of claim 7 , wherein pressing at least one of said plurality of navigation buttons causes the blood pump to run in a forward or reverse direction, such that the air bubble is moved downstream or upstream towards the extraction port.
9. The system of claim 1 , wherein said controller is configured to automatically run said blood pump in a reverse direction when an air bubble is detected.
10. The system of claim 1 , wherein said controller is configured to operate said blood pump in a reverse direction on user input, when an air bubble is detected.
11. In a portable dialysis system for conducting hemodialysis on a patient, a method for removing an air bubble arising in a venous blood line, said method comprising:
detecting the air bubble arising in the venous blood line using an air bubble detector;
issuing an alarm to the patient using a graphical user interface;
electronically prompting a user of the portable dialysis system to select between recovering the air bubble and discontinuing treatment; and
electronically receiving a selection of at least one recovering the air bubble or discontinuing treatment, wherein based upon said received selection,
causing a blood pump to run in a reverse direction such that the air bubble is placed close to an extraction port;
receiving input to confirm that the air bubble is successfully extracted; and
resuming hemodialysis treatment when the user confirms the air bubble is successfully extracted.
12. The method of claim 11 further comprising displaying a plurality of navigation buttons on said graphical user interface based upon electronically receiving the selection of recovering the air bubble.
13. The method of claim 12 , wherein said at least one of said plurality of navigation buttons is configured to adjust a position of the air bubble for extraction from said extraction port.
14. The method of claim 12 , wherein pressing a forward navigation button causes the blood pump to run in a forward direction such that the air bubble is moved downstream towards the extraction port.
15. The method of claim 12 , wherein pressing a reverse navigation button causes the blood pump to run in a reverse direction such that the air bubble is moved upstream towards the extraction port.
16. The method of claim 11 , wherein, upon running the blood pump in the reverse direction, the blood pump operates for a first period of time of the order of 2-15 seconds, and at a rate of around 20-60 ml/min.