progav - aesculapusaifus.com

proGAV ®

CHRISTOPH MIETHKE GMBH & CO. KG

Instructions for UseUSA

0297

CONTENT

INDICATION 4TECHNICAL DESCRIPTION 4FUNCTION OF THE PROGAV 5PHYSICS BACKGROUND 6SELECTING THE APPROPRIATE SHUNT 7ACCESSORIES 8proGAV Verification Tool 8proGAV Masterdisc 8proGAV Compass 8proGAV Adjustment Tool 9proGAV Check-mate 9ADJUSTING THE proGAV 10READING THE PRESSURE SETTING FROM AN X-RAY IMAGE 11POSSIBLE SHUNT COMPONENTS 12TUBE SYSTEMS 12SURGICAL PROCEDURE 12TESTING THE VALVE PATENCY 14VALVE TEST PRIOR TO IMPLANTATION 14TEST RESULTS OF PREIMPLANTATION TEST 15PRESSURE-FLOW CHARACTERISTICS 15TEST ON REFLOW SAFETY 16CONTRAINDICATIONS 16RE-IMPLANTATION 16SAFETY MEASURES 16COMPATIBILITY WITH DIAGNOSTIC PROCEDURES 17MRI INFORMATION 17POSTOPERATIVE VALVE TEST 18FUNCTIONAL SAFETY 18STERILISATION 18CLEANING RECOMMENDATION FOR proGAV Tools WHICH ARE NOT STERILISABLE 18RESTERILISATION 18REQUIREMENTS OF THE MDD 93/42/EEC 18NOTE ON THE INSTRUCTIONS FOR USE 19MEDICAL PRODUCTS CONSULTANT 19GENERAL INFORMATION 19proGAV ADJUSTMENT TROUBLE SHOOTING 20VARIATIONS 21

0297

3

INSTRUCTIONS FOR USE | USA

CAUTIONFederal law restricts this device to sale by or on the order of a physician!

INDICATION

The Miethke proGAV Programmable Shunt System is intended to shunt cerebrospinal fluid (CSF) from the lateral ventricles of the brain into the peritoneum.

TECHNICAL DESCRIPTION

The proGAV is a posture dependent hydroce-phalus valve. It comprises a ball-cone valve with adjustable opening pressure, and a fixed pres-sure gravitational unit. In this way, optimal CSF drainage is ensured for each individual patient in any body position.

Fig. 1: The proGAV is a combination of an adjustable

unit and a gravitational unit.

NOTE: There is limited data for use of this valve system in the pediatric population.

The function of both units is described as fol-lows. Fig. 2 shows a schematic cross section of the proGAV. The adjustable unit is composed of a solid titanium body with a well-tried ball-cone valve (1) integrated in its proximal part. A bow spring (2) defines the opening pressure of the ball-cone valve. The pretensioning of the spring, and thus the valve opening pressure, can be adjusted by turning a rotor (3), with the valve implanted under the patient’s skin.The gravitational unit contains a tantalum ball (4), which defines the opening pressure of this valve, and a sapphire ball (5), which ensures the precise closure of the valve. A connector under the silicone catheter (6) always allows a later disconnection of the catheter if necessary.

FUNCTION OF THE proGAV

The opening pressure of the proGAV is compo-sed of the opening pressure of the adjustable unit and the opening pressure of the gravita-tional unit.

Horizontal positionWhen the patient is lying down, the gravitational unit is always open and therefore does not pre-sent any resistance to the fluid flow.

Fig. 3: Gravitational unit in horizontal position

Hence, the opening pressure of the proGAV is defined, by the adjustable unit. The operational principle of the adjustable unit is illustrated in figures 4a and b. In fig. 4a, the ball-cone valve is closed. The drainage is blocked. In fig. 4b, the adjustable unit is shown in the open condition.

Fig. 4: Adjustable unit a) closed b) open

a)

b)

The patient’s IVP is increased and the spring force, which otherwise keeps closed the ball-cone valve, is overcome. The closing ball moves out of the cone and a gap opens to al-low drainage.

Vertical positionAs soon as the patient moves into an upright position, the gravitational unit closes, the ope-ning pressure of the proGAV is significantly in-creased and CSF drainage is blocked (fig. 5a). Only when the sum of the IVP and the hydro-static pressure exceeds the opening pressure of the proGAV, drainage will be possible again (fig. 5b). The opening pressure of the proGAV in the vertical position is the sum of the opening pressures of both the adjustable unit and the gravitational unit (weight of the tantalum ball).

Fig. 5: Gravitational unit in upright position

a) closed, b) open

a) b)

1 sapphire ball

2 torsion bar

3 rotor

4 tantalum ball

5 sapphire ball

6 connector under the silicone catheter

Fig. 2: Schematic cross section of the proGAV

1

2

3

Adjustable unit

Gravitational unit

6

4 5

| INSTRUCTIONS FOR USE INSTRUCTIONS FOR USE | USA USA

PHYSICS BACKGROUND

The intraventricular pressure is positive in a healthy human in a horizontal position. To ad-just this pressure through shunt drainage, one has to choose the appropriate pressure range, taking into account the abdominal cavity pres-sure. The resulting IVP is the sum of the shunt opening pressure and the abdominal cavity pressure (fig. 6).

The ventricular pressure in a healthy human in a vertical position becomes slightly negative. To maintain this pressure by means of shunt drainage, the shunt opening pressure has to be significantly higher so that the shunt can com-pensate the hydrostatic pressure minus the sum of the abdominal cavity pressure and the slightly negative intraventricular pressure.Conventional shunts open immediately as soon as the patient stands up, which can lead to cri-tical overdrainage.

SELECTING THE APPROPRIATE SHUNT

The proGAV is a position-dependent shunt, meaning the opening pressure changes depen-ding on the position of the patient.

To choose the proGAV for an individual patient, one opening pressure is set for the horizontal position (patient lying down), and one for the vertical position (patient standing upright).

Horizontal position:The opening pressure for the horizontal position is defined by the adjustable unit. The pressure level should be chosen according to the clinical situation and indication. The unit can be adju-sted to a pressure setting between 0 cmH2O and 20 cmH2O.

Vertical position:The opening pressure of the proGAV for the vertical position is calculated by the sum of the opening pressure of the adjustment and of the gravitational unit. The selection of the gra-vitational unit depends on the activity and the abdominal pressure (adiposity). The following opening pressure ranges for the gravitation unit are possible, the pressure range selected can be checked postoperatively on X-ray image:

Opening pressurefor vertical posture

Coding ofgravitational unit

10 cmH2O small, no ring

15 cmH2O large, no ring

20 cmH2O large, 1 ring

25 cmH2O large, 2 rings



Fig. 7: X-ray image of the gravitational unit

a) large, 1 ring = 20 cmH2O,

b) small = 10 cmH2O

Coding ring

proG

AV

proGAV

Fig. 6: Pressure situation at the shunt for horizontal and vertical position

IVP

PVli

PB

PHydhorizontal: IVP = PVli + PB standing: IVP = PHyd - PVst - PB

IVP Intraventricular pressure

PVli Opening pressure in horizontal position

(adjustable unit only)

PVst Opening pressure in vertical position

(adjustable + gravitational unit)

PB Pressure in the abdominal cavity

PHyd Hydrostatic pressure

PVst

IVP

PB

6 7


ACCESSORIES

Caution: Do not use the proGAV Tools near by pacemakers due to magnets inside the proGAV Tools.

Note: These instruments contain ma-terial which has been determinded to be MR-unsafe. DO NOT use in or around strong magnetic fields such as MR ima-ging equipment.

proGAV Verification Tool

The verification tool is used for reading the valve opening pressure setting. First, the verification tool should be placed on the valve. The mar-king (3) on the verification tool must be in line with the proximal (ventricular) catheter. The tool contains two magnets. As soon as the button on the instrument is pushed (2) the magnets in the tool align with the magnets in the valve. The opening pressure is shown on the scale (1).

2

1

3

Fig. 8: proGAV Verification Tool

proGAV Masterdisc

The verification tool can be easily checked by using the proGAV Masterdisc before measuring the opening pressure of the valve. On the disc the positions 0, 5,10,15 and 20 cmH2O are indicated. If the verification tool is placed on the disc the opening pressure shown by the instrument should be aligned to the value of the masterdisc. Example: The proGAV Verification Tool is put on the proGAV Masterdisc so that the marking on the instruments is in line with the value 10 cmH2O on the proGAV Masterdisc. The proGAV Verification Tool should indicate the value of 10 cmH2O.

Fig. 9: proGAV Masterdisc

proGAV Compass

Alongside the proGAV Verification Tool there is an additional device for measuring the adjusted opening pressure. The proGAV Compass can be used to locate the valve when palpation is not possible. The measuring compass is set on the skin over the implanted valve and mo-ved in a circling motion until the internal disc is fixed over the valve. The opening pressure corresponds to the value indicated toward the direction of the ventricular catheter.

Fig. 10: proGAV Compass

proGAV Adjustment Tool

The adjustment tool is used for adjusting the valve opening pressure. First the intended pres-sure setting is selected at the knurled dial (2), the opening pressure is shown on a scale (1). Then the adjustment tool is placed central on the valve. By pushing the button (3), the adjust-ment tip (4) appears, the brake is decoupled, the rotor turns and the adjusted pressure is achieved. The marking (5) on the adjustment tool has to point towards the proximal catheter (leading to the ventricle).

Fig. 11: proGAV Adjustment Tool

3

2

1

54

Warning note: If the implantation site is poorly selected or if the skin over the valve is too thick, adjust-ment of the proGAV can be difficult or some-times impossible. The valve works then as gravitational valve with constant opening pressure. The patient should be informed about the risk.

proGAV Check-mate

The proGAV Check-mate is delivered sterile and is intended to be re-sterilised. It is possi-ble to change and to verify an applied pressure setting on the valve directly. To verify the actual pressure setting the proGAV Check-mate has to be put centrally over the valve. The proGAV Check-mate will immediately start to move. If it remains stable, the pressure setting can be read in alignment to the inlet connector. To adjust a new pressure setting, the proGAV Check-mate has to be placed centrally over the valve. The new pressure setting has to point towards the proximal catheter (leading to the ventricle). By pressing down slightly the proGAV Check-mate, the brake of the valve is decou-pled, the rotor turns and the opening pressure of the proGAV is changed. Please be aware that the steps for changing the pressure setting should not be more than 8 cmH2O per step (see Nr.6, chapter „Adjusting the proGAV“

Fig. 12: proGAV Check-mate

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8 9


ADJUSTING THE proGAV

Each proGAV is calibrated under strict quality control procedures.The presetting of the adjustable unit is 5 cmH2O, but it must be checked before implantation. The setting is changed in the following steps:

1. The valve is located under the skin (fig. 13).

Fig. 13: Locating the valve

2. The verification tool is positioned centrally on the valve. The marking on the instrument has to point towards the proximal catheter (leading to the ventricle). The button is pushed and the pressure setting is read (fig. 14).

Fig. 14: Measuring the pressure setting

a) correctly, b) incorrectly

CHRISTOPH MIETHKE

0...20p ro G A V

a)

b)

Caution: Placing the verification tool in a non-central position on the valve can lead to erroneous readings!

3. The adjustment tool is set to the required opening pressure by turning the knurled dial of the unit (fig. 15).

Caution: The new opening pressure setting of the valves must not differ from the measured opening pressure by more than 8 cmH2O in any one setting (see step Nr.6)

4. The adjustment tool is positioned centrally on the valve. The marking on the instrument has to point towards the proximal catheter (leading to the ventricle).

Fig. 15: Setting the adjustment tool

5. As soon as the adjustment tool has been positioned centrally on the valve, the button is pushed onto the valve and the adjustment tip appears. This triggers the mechanical decoup-ling and the valve setting is adjusted to the re-quired opening pressure setting (fig.16)

Fig. 16: Adjusting the pressure setting

a) b)

Caution: By pushing the button the instru-ment should stay very close to the valve.

6. After the adjustment, the valve opening pres-sure is measured again, as described in step 2. If the pressure measured now differs from the intended pressure level, the adjustment proce-dure has to be repeated from step 3.

After adjusting the proGAV using the proGAV Adjustment Tool, it may be verified using the proGAV Verification Tool and may be confirmed by radiograph (X-ray).

Caution: Due to postoperative swelling of the skin the adjustment of the valve setting may be difficult within the first few days.

Caution: X-ray confirmation may still be ne-cessary for patients with scalp thicknesses greater than or equal to 5 mm thick.

The following table shows the quantitative in-formation regarding the overall agreement rates between the X-ray and the respective verifica-tion tool for the proGAV valve. The maximum deviation from the actual valve readings used were 0, ≤ 1, ≤ 2, > 2 cmH2O. For example at ≤ 2 cmH2O 99.1% of the measurements made by the proGAV VERIFICATION TOOL with the proGAV valve deviate not more than ± 2 cmH2O from the actual value of the valve. The agreement rates are based on non-clinical testing with readings of 15 valves by 15 clinical users under simulated use conditions, yielding a total of 225 readings with each valve and ve-rification tool or compass.

= 0 cmH2O

≤ 1 cmH2O

≤ 2 cmH2O

> 2 cmH2O

proGAV VERIFICATION TOOL

proGAV Valve 33.3 % 93.8 % 99.1 % 0.9 %

proGAV VERIFICATION COMPASS

proGAV Valve

47.6 % 97.3 % 99.1 % 0.9 %

During the adjustment the opening pressure of the adjustable unit should not be changed more than 8 cmH2O per adjustment procedure.

Example: Opening pressure is to be changed from 3 to 18 cmH2O. With only one adjustment procedure the rotor would turn in a counter clockwise direction (short way) and would stop at the position 0 cmH2O (fig. 17a). The correct adjustment is in 2 steps: Adjustment from 3 to 11, and from 11 to 18 cmH2O. The ro-tor turns now in a clockwise direction (fig. 17b).

0

3 3

11

18a) b)

Fig. 17: Rotor rotation during adjustment

a) false b) correct

READING THE PRESSURE SETTING FROM AN X-RAY IMAGE

The pressure setting of the proGAV should be measured with the verification tool, but if there is any discrepancy between the desired adjust-ment setting and the setting that is read by the verification tool, then radiographic confirmation (x-ray) can be performed to confirm the actu-al valve setting. The magnets are visible in the image as white dots. The direction of the rotor tip indicates the pressure setting. The rotor tip can take any position outside region (Fig. 18a). Thus, the opening pressure of the proGAV can be adjusted in increments of 1 cmH2O between 0 and 20 cmH2O.In order to avoid misidentification of the adju-sted opening pressure in the X-ray image, the valve is flattened on one side.

Fig. 18a: Schematic X-ray image

0

1

3 7

9

11

1920

rangenot adjustable

valve is flattened on one side

Fig. 18b: X-ray image position 0 cmH2O

10 11


POSSIBLE SHUNT COMPONENTS

The proGAV is available with different shunt accessories. These variants are comprised of a variety of components, which are described briefly introduced below:

The borehole reservoir is positioned in the cra-nial borehole. It allows flushing and extraction of CSF. Its solid titanium base is highly puncture-re-sistant. All reservoirs are available with integrated catheters or titanium connectors. A special bo-rehole reservoir is the SPRUNG RESERVOIR. As additional new feature of this reservoir CSF can be flushed towards the valve because of a one-way valve in the bottom of the reservoir. By this mechanism a flow in the direction of the ventri-cular catheter is avoided during the pumping procedure. The opening pressure of the shunt system is not increased by the implantation of the SPRUNG RESERVOIR.

The prechamber is positioned on the craniu m. It allows flushing and extraction of CSF and performing palpatory ventricle inspection. Its solid titanium base is highly puncture-resistant. A puncture of the prechamber or the control reservoir should be performed as perpendi-cular to the reservoir surface as possible with a cannula of max. 0,9 mm. 30 times of punc-tures are able without any restrictions. A special prechamber is the CONTROL RESERVOIR. As an additional new feature of this reservoir, CSF can be flushed towards the valve because of a one-way valve in the proximal inlet of the reser-voir. By this mechanism a flow in the direction of the ventricular catheter is avoided during the pumping procedure. The opening pressure of the shunt system is not increased by the im-plantation of the CONTROL RESERVOIR.

Warning note: Frequent pumping can lead to overdrainage and thus to unphysiological pressure conditions. The patient should be informed about the risk.

Due to its tight fit on the ventricular catheter, the deflector allows choosing the length of catheter penetrating into the skull prior to implantation. The ventricular catheter is deflected at a right angle in the borehole (see chapter “Variants”).

TUBE SYSTEMS

The proGAV has been designed to ensure the optimal ventricular pressure. It is available as a shunt system or as individual valve units with or without an integrated distal catheter (internal diameter 1.2 mm, external diameter 2.5 mm). Individual valve units should be used with ca-theters of approx. 1.2 mm internal diameter and approx. 2.5 mm external diameter. The connector on the valve allows using catheters of 1.0 mm to 1.5 mm internal diameter. The ex-ternal diameter of the catheter should be about double the internal diameter. In any case, the catheters must be carefully fixed with a ligature to the valve connectors. Kinks in the catheter have to be avoided.The provided catheters have virtually no effect on the pressure-flow characteristics.

SURGICAL PROCEDURE

Positioning the ventricular catheterSeveral surgical techniques are available for po-sitioning the ventricular catheter. The necessary skin incision should be carried out, preferably, in the shape of a lobule pedicled towards the draining catheter or as a straight skin incision. To avoid CSF leakage, care should be taken that the dura opening is kept as small as possi-ble after applying the borehole. The ventricular catheter is stiffened by the introducing stylet supplied with the product.

The proGAV is available in different shunt va-riants:When using a proGAV SHUNTSYSTEM with borehole reservoir or SPRUNG RESERVOIR, the ventricular catheter is implanted first. Once the introducing stylet has been removed, the patency of the ventricular catheter can be te-sted by checking if CSF is dripping out. The ca-theter is shortened and the borehole reservoir is connected, with the connection secured with a ligature. The skin incision should not be located directly above the reservoir. The proGAV SHUNTSYSTEM with prechamber or CONTROL RESERVOIR comes with a de-flector. This deflector is used for adjusting the position of deflection before implantation of the ventricular catheter. The catheter is deflected;

the prechamber is put into place. The position of the ventricular catheter should be inspected again by postoperative CT or MR imaging.

Positioning the proGAVThe adjustable unit of the proGAV is supplied with a factory setting of 5 cmH2O. This ope-ning pressure can be set to a different value prior to implantation (see chapter “Adjusting the proGAV”). The gravitational unit of the proGAV is a posture-dependent valve. Therefore, care must be taken that the unit is implanted parallel to the body axis. A suitable implantation site is behind the ear.After the skin incision and tunneling under the skin, the catheter is pushed forward, from the borehole to the intended shunt implantation site. The catheter is shortened, if necessary, and secured at the proGAV with a ligature. The shunt should not be located directly under the skin incision. The valve is marked with an arrow pointing in the direction of flow (arrow pointing to distal or downward).

Warning note: The adjustable unit must be placed over a hard boney surface and should not be implanted within an area, which makes finding and feeling the valve more difficult (e. g. under a scar). Frequent pumping can lead to overdrainage and thus to unphysiological pressure condi-tions. The patient should be informed about the risk.

Positioning the peritoneal catheterThe access site for the peritoneal catheter is left to the surgeon’s discretion. It can be applied e. g. para-umbilically in a horizontal direction or transrectally at the height of the epigastri-um. Likewise, various surgical techniques are available for positioning the peritoneal catheter.We recommend pulling through the peritoneal catheter, using a subcutaneous tunneling tool and perhaps with an auxiliary incision, from the shunt to intended position of the catheter. The peritoneal catheter, which is usually securely at-tached to the proGAV, has an open distal end, but no wall slits. Following the exposure of, and the entry into, the peritoneum by means of a trocar, the peritoneal catheter (shortened, if ne-cessary) is pushed forward into the open space in the abdominal cavity.

12 13


TESTING THE VALVE PATENCY

Fig. 19: Patency test

proG

AV

proG

AV

isotonic sterile sodium chloride solution

The proGAV can be filled most gently by aspiration through a ste-rile, single-use syringe attached to the distal end of the catheter. The proximal end of the valve is immersed in a sterile, physiological saline solution. The valve is patent if fluid can be extracted in this way (see fig. 19).Caution: Pressure admission through the single-use syringe should be avoided, both at the proximal and the distal end.Contaminations in the solution used for the test can impair the product’s performance.

VALVE TEST PRIOR TO IMPLANTATION

Each proGAV valve has been tested to ensure that the perfor-mance specifications given on the label are always met. The dyna-mic performance characteristics of the shunt cannot be tested in a static test performed in the operating room.

If the surgeon wishes to verify, prior to implantation, that the shunt meets the specifications given by the manufacturer, the test de-scribed in the following can be carried out in the operating room:Caution: Always take care that sterility is maintained and par-ticle contamination is avoided.

Test methodEquipment required for this test:a) sterile fluid reservoir or water bathb) sterile fluid 60-cm water manometer with millimeter grading and three- branch faucet at the basec) sterile syringe, 30 cc to 50 ccd) sterile 5-µ tip filtere) sterile tube adapterf) sterile silicone tube

CH

RIST

OPH

MIE

THKE

0...20

proG

AV

60 cm

7

20

1a

3

4

45

6

1b

CHRISTOPH MIETHKE0...20proGAV

0

Fig. 20: Test setup1 proGAV a) horizontal, b) vertical; 2 water bath; 3 constant water level; 4 silicone tube; 5 three-way tap; 6 single-use syringe with syringe filter; 7 manometer

Setting up the equipmenta) Position the manometer and the water bath in such a way that the zero point of the manometer and the fluid level of the water bath are at the same height (see fig. 20).b) Fill the syringe, with the 5-µ tip filter attached, with sterile water (Always use the 5-µ tip filter when topping up the syringe.). Remo-ve the tip filter when the syringe is full.c) Connect the syringe, the manometer and the silicone tube with each other. Use the tube adapter if necessary. (see fig. 20)d) To release all air from the test assembly, turn the three-way fau-cet as shown in fig. 21.e) Immerse the silicone tube in the sterile water bath and rinse it with the sterile water from the syringe.

Calibrating the equipmenta) Turn the three-way faucet as shown in fig. 22 and fill the mano-meter to at least 5 cmH2O.b) With the silicone tube immersed in the water bath, turn the three-way faucet so that the syringe is isolated from the mano-meter (see fig. 23).c) Allow the water column in the manometer to drop.d) The water column should stop dropping at the zero point. Adjust the zero point of the manometer to fluid level of the water bath, if necessary.e) The manometer has now been calibrated to the zero-level of the water bath. Fixate the manometer to maintain its position in relation to the water bath.

closed

from syringeto valve

open

Fig. 22

open

to valve

from syringe

closed

Fig. 23

to valve

closed

from syringe

Fig. 21

Test procedurePlease note: During the test the shunt must be submerged in the water bath. The zero point of the manometer has to be aligned with the water level of the water bath in order to obtain correct results.a) Connect the sterile shunt to be tested to the ready assembled, sterile test equipment.b) Turn the three-way faucet as shown in fig. 22 and fill the ma-nometer to 10 cmH2O above the expected opening pressure. (Example: For testing a proGAV with an opening pressure setting of 5 cmH2O horizontal and 25 cmH2O vertical, the manometer is filled to 15 cmH2O with the shunt in a horizontal position and to 40 cmH2O with the shunt in a vertical position.)c) Turn the three-way faucet as shown in fig. 21 so that the ma-nometer is isolated.

d) Remove all air from the shunt and the test setup by carefully rinsing it through with sterile water from the syringe.e) Immerse the sterile shunt in the sterile water bath. The distal part of the shunt must be under water to obtain valid test results.f) Carefully maintain a flow through the shunt and turn the three-way faucet as shown in fig. 23 to isolate the syringe. As soon as the three-way faucet is in the correct position, the water column should begin to drop.The syringe is now isolated from the valve and it is not necessary anymore to maintain its flow. Repeat steps b to f if the water co-lumn fails to drop.g) Allow the water level in the manometer to drop for 2 to 2.5 mi-nutes. Read the resulting pressure at the manometer.

TEST RESULTS OF PREIMPLANTATION TEST

The following table shows results, which should be achieved by this method, for some selected pressure levels:

Pressure rating (cmH2O) Acceptable pressure ranges

adjustable unitgravitatio-nal unit

horizontal vertical

0 10 0-5 cmH2O 5-15 cmH2O

0 20 0-5 cmH2O 10-25 cmH2O

10 10 5-15 cmH2O 10-25 cmH2O

10 20 5-15 cmH2O 15-35 cmH2O

20 20 10-25 cmH2O 20-45 cmH2O

20 30 10-25 cmH2O 25-55 cmH2O

20 35 10-25 cmH2O 27-60 cmH2O

Table 1: Selected pressure ranges

PRESSURE-FLOW CHARACTERISTICS

Horizontal positionThe following diagrams show the pressure-flow characteristics of the adjustable unit of the proGAV for the pressure settings 0, 10 and 20 cmH2O.

Fig. 24 Pressure-flow characteristics for some pressure settings of the adjustable unit

5

10

10 20 30 400 5 2515 35 45 50 55

15

20

25

30pr

essu

re (

cm

H2O

)

flow (ml/h)

Adjustable unit 20 cmH2O



Vertical positionThe opening pressure of the proGAV in the vertical position is the sum of the opening pressure of the adjustable unit and the gravi-tational unit. The following diagrams shows the pressure-flow-cha-racteristics for some pressure settings in the vertical body position.

5

10

15

20

25

10 20 30 400 5 2515 35 45 50 55

30

35

40

45

50

55

60

Gravitational unit 10 cmH2O

pres

sure

( cm

H2O

)

flow (ml/h)




5

10

15

20

25

10 20 30 400 5 2515 35 45 50 55

30

35

40

45

50

55

60


pres

sure

( c

mH

2O)

flow (ml/h)




5

10

15

20

25

10 20 30 400 5 2515 35 45 50 55

30

35

40

45

50

55

60


pres

sure

( cm

H2O

)

flow (ml/h)




5

10

15

20

25

10 20 30 400 5 2515 35 45 50 55

30

35

40

45

50

55

60


pres

sure

( cm

H2O

)flow (ml/h)




14 15


5

10

15

20

25

10 20 30 400 5 2515 35 45 50 55

30

35

40

45

50

55

60


pres

sure

( cm

H2O

)

flow (ml/h)




5

10

15

20

25

10 20 30 400 5 2515 35 45 50 55

30

35

40

45

50

55

60


pres

sure

( cm

H2O

)

flow (ml/h)




The total opening pressure refers to a reference flow of 5 ml/h. When the flowrates reach 20 ml/h, the opening pressures are approximately 1-2 cmH

2O higher.

TEST ON REFLOW SAFETY

This test is carried out with the same equipment as the pre-implan-tation test. The shunt is carefully filled with sterile saline solution from the syringe before the air is removed from it (fig. 25). The shunt is connected against the direction of flow (see arrow on the shunt). The outlet of the shunt has to be at the zero level of the manometer. The manometer is filled up to 14 cmH2O (fig. 26). The three-way faucet is used for unblocking the flow to the shunt and blocking the flow to syringe. In this setup, no more than 2 drops (0.1 cc) per minute should emerge from the proximal part of the shunt (fig. 27).

Caution: Be careful to maintain sterility and to avoid particle contamination.

Fig. 25

proG

AV

isotonic sterile sodium chloride solution

14 cm

0-levelopen

Fig. 26

14 cm

closed

open

0-level

Fig. 27

CONTRAINDICATIONS

The adjustable unit should not be implanted within an area which makes locating and sensing the valve more difficult (e. g. under a scar). The valve should lie on the periost or the bone to make an adjustment after implantation possible.

RE-IMPLANTATION

Under no circumstances should products that have had previously been implanted in one patient be subsequently reimplanted in ano-ther, as a validated decontamination process will compromise the functionality of the valve.

SAFETY MEASURES

The patients must be carefully monitored after the implantation. Reddened skin and tension in the area of the drainage tissue could indicate infections at the shunt system. Symptoms such as hea-dache, dizzy spells, mental confusion or vomiting are common oc-currences in cases of shunt dysfunction. Such symptoms, as well as shunt system leakage, necessitate the immediate replacement of the shunt component responsible, or of the entire shunt system.

COMPATIBILITY WITH DIAGNOSTIC PROCEDURES

MRI examinations with field strengths of up to 3.0 tesla and CT examinations can be carried without endangering or impairing the function-ality of the shunt.The proGAV valve will not change when sub-jected to an MRI of 1.5T or 3T.All components of the proGAV are visible via X-ray. The provided catheters are MRI Safe. Reservoirs, deflectors and connectors are MRI Conditional.

MRI SAFETY INFORMATION

The proGAV programmable valve was deter-mined to be MR Conditional (ASTM F2503-13). According to the results of in vitro testing, a patient with the proGAV may undergo an MRI procedure using an MR system with a static magnetic field of 3T or less. No impact on the performance of the proGAV at 3T or less can be expected.

Warning note: When using a magnetic field and simultaneous pressing on the valve an adjustment of the valve cannot be excluded.

Non-clinical testing has demonstrated the proGAV is MR Conditional.

It can be scanned safely under the following conditions: · static magnetic field of 1.5 and 3 Tesla· spatial gradient field of 4.3 T/m ( =430 G/cm)· maximum whole body ave raged specific absorption rate (SAR) of 2.9 W/kg for 15 minutes of scanning.

In non-clinical testing, the proGAV pro-duces a temperature rise of less than 0.2 °C at a maximum whole body averaged specific absorption rate (SAR) of 2.9 W/kg, as assessed by calorimetry for 15 minutes of scanning in a MR scanner

· 1.5 Tesla Vision Sonata of Siemens Healthcare (Erlangen, Germany), software version Numaris/4 MR A30· 3 Tesla Trio of Siemens Healthcare (Erlangen, Germany), software version Numaris/4 MR B15

To confirm that the valve setting has not been altered by exposure to the MRI scanner, the pressure setting of the adjustable unit can be checked with the proGAV Verification Tool.

Warning note: The proGAV will produce arti-facts or signal-intensity voids in MR images that extends 16 mm beyond the physical size of the device.

closed

Valve orientation

coronal transverse

Imaging plane and phase encoding direction

sagittal ap

sagittal hf

coronal rl

coronal fh

sagittal ap

sagittal hf

coronal rl

coronal fh

TSE artifact in [cm2]

22,76 22,22 20,62 25,68 22,02 20,85 19,84 21,94

Imaging plane sagittal coronal sagittal coronal

GRE artifact in [cm2]

35,27 31,27 25,17 23,98

Artifact size for the proGAV associated with MR imaging at 3T

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As such, the proGAV should not be placed in close proximity to a location, which may re-quire an MR image. Below is a chart containing the signal void associated with the proGAV as tested to ASTM F 2119-07 using a 3 Tesla MR-scanner Magnetom Trio of Siemens at the section on Experimental Radiology in Tübingen, Germany.

The temperature measurement at 3T and 1,5 T showed no increased temperature caused by the implant in a worst-case scenario (static li-quid) test performed at a whole-body averaged SAR of 2,9 W/kg. The results imply, that no additional risk due to radio frequency induced heating is caused to the patient, if the valves are implanted. Testing was conducted in accordance to ASTM F2182-09.

The proGAV had relatively minor magne-tic field interaction, passing the deflection testing of ASTM F2052-06 with no tor-que produced (ASTM F2213-06) and a 22-degree deflection angle. Therefore the proGAV will not present an additional risk or hazard to the patient with the regards to de-flection or torque in the environment of a 3 T magnetic resonance tomography.

POSTOPERATIVE VALVE TEST

The proGAV has been designed as a safe and reliable unit even without the provision of a pumping device. However, there are ways of testing the unit if a shunt system with a prech-amber or a borehole reservoir is used. Valve tests can be carried out by flushing or pressure measurements.

FUNCTIONAL SAFETY

The valves have been designed for long-term reliable and precise operation. Still, it cannot be excluded that the shunt system needs to be re-placed for technical or medical reasons.The valve and the valve system are able to resist positive and negativ pressure up to 200 cmH2O during and after implantation.

Warning note for carriers of pacemakers: Due to the implantation of a proGAV the function of a pacemaker can be affected.

STERILISATION

The products are sterilized with steam under closely monitored conditions. The double wrap-ping in sterile bags ensures sterility for a period of five years. The expiry date is printed on the wrapping of each individual product. Products taken from a damaged wrapping must not be used under any circumstances.

CLEANING RECOMMENDATION FOR proGAV Tools WHICH ARE NOT STERILISABLE

Attention: proGAV Tools are made from ther-mal unstable components which are affec-table by heat or humidity or chemical agres-sive substances. Do not steep the proGAV Tools in liquids and keep the inside of the instruments dry!

Remove surface pollution of the proGAV instru-ments after the use immediately with alcohol ba-sed cleaners (more than 75% alc.) by a wiping procedure. The time of impact should be more than 60 sec. and should be depending on the le-vel of pollution. For final cleaning use a dry wipe.

The following cleaning methods are not al-lowed for the cleaning of the proGAV Tools: Irradiation, Ultrasonic, Sterilization, Machine preparation, Inserting into liquids.

RESTERILISATION

The functional safety and reliability of resterilized products cannot be guaranteed, therefore re-sterilisation is not recommended.

REQUIREMENTS OF THE MDD 93/42/EEC

The MDD calls for the comprehensive docu-mentation of the whereabouts of medical pro-ducts that are applied in human beings, es-pecially the whereabouts of implants. For this reason, the individual identification numbers of any implanted valves are to be noted in pa-tients‘ records, so that in the event of any in-

quiries, the implant can be traced without any difficulties. Each valve is outfitted with a sticker for this purpose.

NOTE ON THE INSTRUCTIONS FOR USE

The descriptions and explanations given in this document are based on the clinical experience available to date. It is for the surgeon to deci-de if surgical procedures should be changed according to his or her experience and to sur-gical practice.

MEDICAL PRODUCTS CONSULTANT

In compliance with the requirements of the Eu-ropean law MDD 93/42/EEC, Christoph Miethke GmbH & Co. KG names medical pro duct con-sultants as the individuals to be addressed with all queries concerning the products:

Dipl.-Ing. Christoph Miethke Dipl.-Ing. Roland Schulz

Christoph Miethke GmbH & Co. KGUlanenweg 2D-14469 Potsdam · GermanyPhone: +49(0) 7000 6438453 orPhone: +49(0) 331 620 83 0Fax: +49(0) 331 620 83 40e-mail: [email protected]

Please address any enquiries to:AESCULAP AG Am Aesculap PlatzD-78532 Tuttlingen · GermanyPhone: +49 (0) 7461 95-0Fax: +49 (0) 7461 95-26 00e-mail: [email protected]

Service address in the USAESCULAP Inc.Attn. AESCULAP Technical Services615 Lambert Pointe RoadHazelwood, MO, 63042

AESCULAP Repair HotlinePhone: +1 (800) 214-3392Fax: +1 (314) 895-4420

Distributor in the US/ Contact in CanadaAESCULAP Inc.3773 Corporate ParkwayCenter Valley, PA 18034Phone: +1-800-282-9000www.aesculapusa.com

GENERAL INFORMATION

Manufacturer Christoph Miethke GmbH & Co. KG

Product name proGAV

Intended use Treatment of Hydrocephalus

Intended for one-time use (disposable)

Store in a clean, dry place

Schematic representation of the valve with its external dimensions:

Height 4,4 mm Height 4,6 mm

18 mm 15 mm

Note: When adjusting the proGAV preope-ratively through the packaging, moderate force with the proGAV Adjustment Tool is sufficient. DO NOT USE THE BUTTON. Strong pressu-re can cause damage to the housing, which might affect valve function.

18 19


Issue The proGAV does not adjust to the pressure setting desired

Resolution Steps Insure that the markings and scale windows on either the Adjustment Tool or the Verification Tool are aligned with the proGAV valve's proximal connector (the one pointing towards the ventricle) when used. Approximately ±15 degrees of misalignment will result in a ±1 cmH2O measurement discrepancy. Note: When adjusting the proGAV in its sterile packaging the arrow on the proGAV points distally towards the peritoneal catheter and distal connector, the proximal connector is opposite the direction pointed by the arrow.

Insure that the desired tool is centered over the proGAV. The Adjustment Tool will not be able to adjust the proGAV unless it is located over the center of the proGAV. The Verification Tool will not provide accurate readings unless it is also centered over the proGAV. Note: For thick skin where the proGAV can not be palpated, use the Verification Compass to locate the center of the proGAV valve.

The proGAV can be adjusted without completely pushing down on the Adjustment Tool's but-ton for patients with thin skin covering the proGAV or while the proGAV is still in its sterile packaging. However, this is NOT the case for patients with thick skin or scar tissue covering the proGAV. For these patients, insure that the tool is pressed firmly against the proGAV valve and that the button on the tool is pressed down completely. If the patient moves their head away when pressing the button on the tool, you may need to steady the patient's head by supplying support with your hand on the opposite side of their head.

Check the accuracy of the Verification Tool against the Masterdisc. If the measurements of the Verification Tool do not match with the Masterdisc, use a different Verification Tool, the Verification Compass, or an X-ray scan to obtain the setting confirmation. If the Verification Tool is accurate, try using an alternate Adjustment Tool.

Multiple attempts to adjust the proGAV may be required in some cases. Typically and experienced user will be able to complete an adjustment procedure with 3 attempts or less. However, for patients with thick skin and/or scar tissue covering the valve studies have shown that up to 10 attempts may be required to complete the proGAV adjustment. The clinical condition of the skin above the valve is the only limiting factor with regard to the number of adjustment attempts. The maximum distance possible for readjusting the valve is approximately 10 mm from the base of the Adjustment Tool to the top surface of the proGAV.

Was the desired change in pressure settings greater than 8 cmH2O? See note on page 11. Repeat reprogramming, but use a smaller increment of change. Thus, it may require more than one adjustment to reach the desired pressure setting.

VARIATIONS

The proGAV is available as a single valve or as a shunt system comprising various components.

proGAV

proGAV SHUNTSYSTEM

Scale: 1:1

proGAV ADJUSTMENT TROUBLE SHOOTING

proGAV SHUNTSYSTEM with SPRUNG RESERVOIR or with (pediatric) borehole reservoir

proGAV SHUNTSYSTEM with CONTROL RESERVOIR or with (pediatric) prechamber

20 21


TA 011544 GBA_80_12_0217_USA

CE-Kennzeichnung gemäß Richtlinie 93/42/EWGCE marking according to directive 93/42/EECLabel CE conforme à la directive 93/42/CEEIdentificatión CE en conformidad con la directriz 93/42/CEEMarchio CE conforme alla direttiva 93/42/CEE

Technische Änderungen vorbehaltenTechnical alterations reservedSous réserve de modifications techniquesSujeto a modificationes técnicasCon riserva di modifiche tecniche

Manufacturer acc. MDD 93/42/EEC:

CHRISTOPH MIETHKE GMBH & CO. KG

Christoph Miethke GmbH & Co. KG | Ulanenweg 2 | 14469 Potsdam | GermanyPhone +49 (0) 331 62 083-0 | Fax +49 (0) 331 62 083-40 | www.miethke.com

Distributed by:

Aesculap AG | Am Aesculap-Platz | 78532 Tuttlingen | GermanyPhone +49 (0) 7461 95-0 | Fax +49 (0) 74 61 95-26 00 | www.aesculap.com

Aesculap - a B. Braun company

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progav - aesculapusaifus.com

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