Cobe Centrysystem 3 Calibration procedures

Calibration Procedures on Cobe Centrysystem 3:

I) Balance Chamber Calibration:

- Verify that pressure regulators PRV and PRV2 are calibrated as well as pressure

transducers PDI and PDO with switches SW2 and SW1-8 are closed (after switching
system power off, setting the calibration switches SW2 and SW1-8 to CAL position
(i.e. down) is necessary to enter into the calibration mode).

- Switch the power button on, select calibrate option C, and keep selecting until

“Balance Chamber” option appears.

- Start calibration.

- Step 1: Bypass the machine by shunting the bypass ports.

- Step 2: Remove bypass mode. The numbers corresponding to LS1 and LS2 appear on

the screen (chamber 1 and 2 diaphragms are forced to the left by dialysate prep
system in the chamber i.e. HL1 and HL2). The numbers should increase from 0000 to
above 0040. If not, then replace the affected CCA Hall-effect sensor. Wait for 2
minutes so the values can stabilize.

- Step 3: GP3 pump forces the chamber diaphragms 1 and 2 to the right side HR1 and

HR2.The numbers should start at 00FF and decrease beyond 00D0. If not, then
replace the affected CCA Hall-effect sensor.

- Step 4: The numbers of the NOVRAM # 67 to # 70 (UFC 8/6 M&L and

UFC 8/7 M&L) appear. Turn the switches on the UF board on and store the values
recorded.

- Check the status for dialysate flow (should be ± 30 mL/min within 500 mL/min).

- Check UF service screen 1 (window 1).

- Verify that the control bytes are within 3 of each other: 8M (chamber 1 flow) and 8L

(chamber 2 flow).

- Verify that control bytes are within 5 within each other:

4L (chamber 1 fill time)
5L (chamber 2 fill time)
6L (chamber 1 cycle time)
7L (chamber 2 cycle time)

- Repeat calibration until desired results are reached otherwise set SW2 and SW1-8

open.

II) Dialysate Pressure Transducer Calibration (PDO and PDI):

- There is a need for clamps, a T-connector and a syringe.

- The setup diagram is shown below in Figure 2:

Figure 1 - Setup for Dialysate Pressure Transducer Calibration

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- Verify switches SW2 and SW1-8 are closed after switching the system power off.

- Switch power button on, select calibrate option C, and keep selecting until “Dialysate

Pressure Transducers” option appears.

- Start calibration.

- Step 1: Bypass the machine, clamp the tubing with padded hemostats at output of

PDO between PDO and bypass tee. Mark tubing between PDO transducer and check
valve with piece of tape. Remove tubing from PDO transducer at check valve.
Remove tubing from PDI transducer at fluid ground. Remove any water from tubing.
Connect the 2 tubing pieces with chevron or T connector. Connect the pressure meter
Neo-2 and syringe to T-connector ports. Adjust the syringe until the pressure meter
reads -300 mmHg for 3 seconds. The numbers on the screen should be between 30 to
50 H. Continue the process of calibration.

- Step 2: Adjust the syringe until pressure meter reads 300 mmHg for 3 seconds. The

numbers on the screen should be between B0 to D0 H. Continue the process of
calibration.

- Step 3: Adjust the syringe until the pressure meter reads -300 mmHg for 3 seconds.

The numbers on the screen should read 30 to 50 H. Continue the process of
calibration.

- Step 4: Adjust the syringe until the pressure meter reads 300 mmHg for 3 seconds.

The numbers on the screen should be between B0 to D0 H. Continue the process of
calibration.

- Step 5: The displayed numbers are:

PDO Gain NOVRAM # 81 – UFC 9/5M (control)
PDO Offset NOVRAM # 82 – UFC 9/5L (control)
PDO Gain NOVRAM # 119 – UFM 9/8L (monitor)
PDO Offset NOVRAM # 120 – UFM 9/9M (monitor)
PDI Gain NOVRAM # 117 – UFM 9/7L (monitor)
PDI Offset NOVRAM # 118 – UFM 9/8M (monitor)

- Save and store the parameter values and then switch SW2 and SW1-8 on.

III) Blood Handling Pressure Transducer Calibration (Arterial/Venous Pressure

Transducers):

- Set the switches SW2 and SW1-8 down after turning the system power off. Turn the

power button on, go to the option “Calibrate”, and then select option A “Automatic
Calibration”. Select “Blood Handling Pressure Transducers”.

- Start calibration.

- Step 1: Connect the pressure meter and syringe to the “Venous Pressure” transducer

(to the left); adjust the syringe until the pressure reading is 300 mmHg for 3 seconds;
continue.

- Step 2: Move the meter and syringe to “Arterial Pressure” transducer; adjust the

syringe until the pressure reading is -300 mmHg for 3 seconds; continue.

- Step 3: Move the meter and syringe and open the transducers to the atmospheric

pressure for 3 seconds; continue.

- Step 4: The displayed values are:

Art. Pres. Offset (control) NOVRAM # 129 – BHC 2/6M
Ven. Pres. Offset (control) NOVRAM # 130 – BHC 2/6L
Art. Pres. Gain (control) NOVRAM # 131 – BHC 2/7M
Ven. Pres. Gain (control) NOVRAM # 132 – BHC 2/7L
Art. Pres. Offset (monitor) NOVRAM # 145 – BHM 2/6M
Ven. Pres. Offset (monitor) NOVRAM # 146 – BHM 2/6L
Art. Pres. Gain (monitor) NOVRAM # 147 – BHM 2/7M
Ven. Pres. Gain (monitor) NOVRAM # 148 – BHM 2/7L

- Save and store the parameter values. Switch SW2 and SW1-8 back on. Prove with the

status screen (“Run” mode) that the “Arterial Pressure” and “Venous Pressure” are

-4 to 4 mmHg. Connect the pressure meter and syringe to the “Venous Pressure”
transducer (left) and adjust the syringe until the pressure is -40 mmHg on the pressure
meter while the “Venous Pressure” reads on display -36 to -44 mmHg. Adjust the
syringe until the pressure is 380 mmHg; verify the “Venous Pressure” reads
372 to 388 mmHg and clamp the line so that the read pressure is 360 to 400 mmHg
with the line clamped. Move the meter and syringe to the “Arterial Pressure”
transducer and adjust the syringe similar to the “Venous Pressure” transducer but with

complementary values 40 mmHg, 36 to 44 mmHg, -372 to -388 mmHg, and

-360 to -400 mmHg.

- Allow the temperature to stabilize for 5 seconds and monitor the “Venous Pressure”

and “Arterial Pressure” for two minutes. If a change of more than 4 mmHg is
recorded, locate and repair the leak as well as re-conduct the test.

IV) Dialysate Flow Calibration (GP1):

- Set the switches SW2 and SW1-8 down after turning the system power off. Turn the

power button on, go to the option “Calibrate”, and then select option C “Device
Calibration”. Select “Dialysate Flow”.

- Start calibration.

- Step 1: The parameters appearing on the screen are:

Flow Gain 70 – A8 H
Flow Offset 00 – 50 H
Flow / Temperature Corr. 00 – 20 H

The above values are the allowed ranges which can be acquired. If any value is out of
its respective range, select “Exit” option B: if the flow gain is out of range, set
NOVRAM # 6 to 85 H; if the flow offset is out of range, set NOVRAM # 5 to 35 H;
if the flow / temperature corr. is out of range, set NOVRAM # 7 to 06 H. After
changing the appropriate NOVRAM parameter, exit and store the value.

- Step 2: A timer of 60 seconds allows the flow to go up to 400 mL/min.

- Step 3: Place the drain hose in a graduated cylinder (of capacity 750 mL) and

measure the flow for 1 minute; press modify to change the flow value as indicated by
the graduated cylinder (if the value is far off from 400 mL, a higher reading is traced
to a malfunctioning flow pump GP2 or GP1 or a leak in the vacuum system while a
low reading is traced to a leak in the drain system).

- Step 4: A timer of 60 seconds allows the flow to go up to 600 mL/min.

- Step 5: Place the drain hose in the graduated cylinder and measure the flow for

1 minute; press modify to change the flow value as indicated by the graduated
cylinder (if the value is far off from 600 mL, a higher reading is traced to a
malfunctioning flow pump GP2 or GP1 or a leak in the vacuum system while a low
reading is traced to a leak in the drain system).

- Save and store the parameter values and then switch SW2 and SW1-8 on.

- Select “Run” mode in order to operate the system. The flow should be within

± 30 mL/min form the value of Operating parameter # 21 which corresponds to the
dialysate flow rate.

V) Deaeration Level Sensor Calibration (LS1):

- Set the switches SW2 and SW1-8 down after switching the system power off. Turn

the power button on, go to the option “Calibrate”, and then select option C “Device
Calibration”. Select “Deaeration Level Sensor”.

- Start calibration.

- Step 1: V1 is turned off so that no water enters the machine; therefore, LS1 is forced

to its lowest level. Wait for 1 minute, and then press continue.

- Step 2: V1 is turned full on; hence, LS1 is forced to its highest level. Wait for

1 minute, and then press continue.

- Step 3: The displayed numbers on the screen are:

LS1 Trip Point (hi) (control) NOVRAM # 1 – DPC E/5M
LS1 Trip Point (lo) (control) NOVRAM # 2 – DPC E/5L
LS1 Trip Point (hi) (monitor) NOVRAM # 47 – DPM 3/8M
LS1 Trip Point (lo) (monitor) NOVRAM # 48 – DPM 3/8L

- Save and store the parameter values and then switch SW2 and SW1-8 on.

- Select “Run” mode in order to operate the system.

- Verify the readings as follows:

1. Turn off the water for 1 minute.

2. Select the DP1 service screen 6.

3. The values of the control byte 7M and the monitor byte 7L appear.

4. Add the bits to each value.

5. Select the DP service screen E.

6. Verify that the control byte 5L reads within 5 bits of the monitor byte 7L

adjusted value.

7. Turn the water on, power off then power on.

8. Press fill and wait 1 minute.

9. Select the DP service screen 6.

10. The values of the control byte 7M and monitor byte 7L appear.

11. Subtract 8 bits from each number.

12. Select the DP service screen E.

13. Verify that the control byte 5M reads within 5 bits of the control byte 7M

adjusted value.

14. Select DP service screen 3.

15. Verify that the monitor byte 8M reads within 5 bits of the monitor byte 7L

adjusted value.

16. If the values fall within specification, the new parameters are reserved;

otherwise the calibration process is repeated.

VI) Blood Leak Calibration:

- Set the switches SW2 and SW1-8 down after switching the system power off. Turn

the power button on, go to the option “Calibrate”, and then select option C “Device
Calibration”. Select “Blood Leak Calibration”.

- Start calibration (with dialyzer hoses connected to shunt block).

- Step 1: A timer of 20 minutes allows the blood leak detector calibrate.

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DP: Dialysate Pressure