1. Single Needle Hemodialysis
Caution: Federal Law (USA) restricts this device to sale,
by or on the order of a physician.
Read Instruction for Use prior to patient application.
Trademarks used herein are owned by or licensed to Gambro
2006 Gambro Rev B

2. Objectives Rationale for Single Needle (SN) Dialysis
History of SN Dialysis Systems
Phoenix SN
Stroke Volume & Clearance Efficiency
Effects of Changing Pressure Limits & Blood Flow

3. Why Single Needle?
Consistent access to the blood is the weakest link in the hemodialysis process.

4. History of SN Dialysis Control Systems
Pressure – Time
Continuous Pump
Vital Assists
Average Pressure
Intermittent Pump
COBE Centry® SNC (C2)
Pressure – Pressure
Centrysystem® 3/3+
Phoenix®
Continuous Pump (Double Blood Pump)
AK 10
Fresenius + =
LOW
HIGH
AVERAGE
LOW
HIGH

5. SN CYCLE All SN systems have two operating Phases Arterial Phase
Blood drawn FROM the patient
Venous Phase
Blood returned TO the patient
The combination of the two is referred to as a “CYCLE”

6. Phoenix® Single Needle
Utilizes a Pressure – Pressure control device incorporating the intermittent blood pump and A/V clamping device
The operator sets a SN Pressure Max (venous pressure) limit to end the Arterial Phase
AND
a SN Pressure Min (venous pressure) limit to end the Venous Phase
Note: SN Pressure Min/Max = Venous Pressure Min/Max

7. Arterial Phase Description
Blood Pump is ON
Arterial Clamp is Open
Venous Clamp is Closed
When the SN Pressure Max (venous pressure) limit is reached the machine switches to the Venous Phase

8. Venous Phase Description
Blood Pump is OFF
Arterial Clamp is Closed
Venous Clamp is Open
Blood returns to the patient until the SN Pressure Min (venous pressure) limit is reached triggering another Arterial Phase
(The blood is returned by the pressure built up in the system)

9. Stroke Volume & Clearance Efficiency
Clearance Efficiency in single needle dialysis is a function of:
Stroke Volume
Access Recirculation
Average Blood Flow Rate
Blood Tubing Compliance

10. Stroke Volume Optimum Stroke Volume = 20 – 30 mls
Is the quantity of blood removed from the patient in one Arterial Phase
Is relative to how high the SN Pressure Max (venous pressure) limit is set
Optimum Stroke Volume = 20 – 30 mls

11. Stroke Volume (continued)
By increasing the volume of blood pumped with one stroke, the percent of that volume being recirculated is Decreased
Stroke Volume is optimized on the Phoenix® system using a unique Cartridge Blood Set configuration which includes 1 or 2 pumping chambers and the operator’s ability to manipulate blood side pressure limits

12. Stroke Volume Calculation
The Phoenix® system calculates the Stroke Volume:
Arterial Phase Time X Pump Speed 60

13. Sources of Recirculation
Poor blood flow from patient’s access
Common space in the Access Device
Fistula needle or Single Lumen Catheter
Compliance of the blood lines

14. Recirculation
Recirculation is the drawing of dialyzed blood from the Venous Line into the Arterial Line before it circulates through the patient
Dialyzed blood has a lower concentration of solutes than the blood in the patient’s circulatory system, therefore Recirculation can adversely affect clearance efficiency

15. Common Space 1.
Is the space from the tip of the needle to the start of the Y where venous and arterial blood mix
Use of standard Fistula needle is not recommended due to the common space volume 2.
Optimum volume of
common space is 0.5 mL

16. Common Space = Recirculation
A/V Fistula needle with a Y adapter attached is not recommended
12” Fistula Needle w/ tubing = 2.6 – 2.9 ml volume
Use an Access Device designed for Single Needle

17. Common Space = Recirculation
This chart illustrates Common Space Volume as related to % of Recirculation at a certain Stroke Volume

18. Access Device designed for Single Needle
Pictured below is a fistula needle designed for SN as compared to a standard fistula needle
As you can see the common space is vastly different
SN ”Y “ Set
Fistula Needle
Standard Fistula
Needle with
12” Tubing

19. Blood Flow Rate Phoenix® system calculates Blood Flow rate as:
Pump Speed x Active Time of Blood Pump
Cycle Time

20. Blood Tubing Compliance
Recirculation may be caused by the compliance of the blood tubing set during single needle procedures
Pressure differentials as great as 600 mmHg (-200 mmHg arterial, +380 mmHg venous) may occur between venous and arterial phases, causing expansion and contraction of the tubing

21. Blood Tubing Compliance continued
This expansion and contraction causes backflow during the arterial and venous phases
Lastly, due to the configuration of the Cartridge Blood Set, blood flow is continuous through the dialyzer

22. Effects of Adjusting Pressure Limits
Increase
SN Pressure Max to:
Stroke Volume
Average Blood Flow Rate
Arterial Phase Time
Decrease
SN Pressure Max to:
Stroke Volume
Average Blood Flow Rate
Arterial Phase Time

23. Effects of Adjusting Pressure Limits
Increase
SN Pressure Min to:
Stroke Volume
Average Blood Flow Rate
Venous Phase Time
Decrease
SN Pressure Min to:
Stroke Volume
Average Blood Flow Rate
Venous Phase Time

24. Effects of Adjusting Pump Speed
Raising or Lowering Pump Speed will:
Change blood flow rate
speed, arterial phase time
Possible change in stroke volume

25. Gambro® Product Offerings
Cartridge Blood Sets:
Single Needle Set P/N
Single Needle Set w/prime line attached P/N
Single Needle Conversion Kit P/N
Y Connector P/N S-194C
For use with a Single Lumen Catheter