Contraindications; Side Effects - Integra OSV II Lumbar Valve Systems Mode D'emploi

DESCRIPTION
The Integra® OSV II® Lumbar hydrocephalus Valve System is an implantable device for controlled cerebrospinal fluid (CSF) drai-
nage from the lumbar subarachnoid region to the peritoneal cavity. Unlike conventional valves, the OSV II Lumbar Valve System
is a variable resistance valve which maintains drainage rate close to the CSF secretion rate (20 ml/hr) within the physiological
range of intracranial pressure (ICP). The mechanism incorporates a safety pressure relief mode to prevent accidental intracranial
hypertension.
Caution: The Integra OSV II Lumbar Valve may appear similar to the Integra® Flow Regulating Valve Low Flow, Lumbar, however,
the Integra Flow Regulating Valve Low Flow, Lumbar features a black, radiopaque flow direction arrow to differentiate both
products: visually during implantation and by X-ray after implantation (Figure 4).
WARNING:
The Integra OSV II Lumbar Valve should be used in patients who need a drainage rate close to the CSF secretion rate (18-30 ml/
hr). For patients who need a lower drainage rate (8-17 ml/hr), the Integra Flow Regulating Valve Low Flow, Lumbar should be used.
Principles of Operation
The variable flow restrictor (Figure 1) consists of a silicone elastomer diaphragm (4), synthetic ruby seat (5), and notched pin (6).
The diaphragm reacts to differential pressure (DP) variations. The seat is inserted into the center of the diaphragm. As differential
pressure varies, the clearance between the seat and the pin increases or decreases depending on seat movement along the pin.
Changes in the seat and pin clearance vary flow rates. A typical flow/pressure curve is shown in Figure 2.
Note - Differential pressure/flow characteristics for each valve are verified to be within specification at time of manufacture.
The three stages of operation of the OSV II Lumbar Valve System are defined below:
Stage I Low Differential Pressure
This stage begins when the flow rate through the valve reaches 5ml/hr (DP will be between 30 and 80 mm H₂0). The valve
remains in Stage I with CSF flow rates up to 18 ml/hr (DP will be between 40 and 120 mm H₂0).
Stage II Flow Regulation
When the DP increases, the valve operates as a variable resistance flow regulator. At DP ranges between 120 and 300 mm H₂0,
the valve restricts flow between 18 and 30 ml/hr.
Stage III Pressure Relief Mode
Should the intraventricular pressure (IVP) elevate abruptly, the shunt operates in a rapid flow rate mode to facilitate IVP norma-
lization. The valve then reverts to Stage II or I, depending upon conditions.
Configurations
The system is available in two configurations: valve with or without antechamber (see product label). The system consists of a
valve with pre-attached, proximal tubing and pre-attached distal catheter, one F5 lumbar catheter, one guidewire, one 14G Tuohy
needle, one suture clamp, one step-down connector, one luer connector and one straight connector.
Materials
Materials in contact with body tissues or body fluids are silicone elastomer with or without barium sulfate, polysulfone, synthe-
tic ruby, silicone adhesive, polypropylene, epoxy, stainless steel, polycarbonate and PTFE.
INDICATIONS
The OSV II Lumbar Valve System is an implantable system used in the treatment of patients with communicating hydrocephalus
to shunt CSF from the lumbar subarachnoid region to the peritoneal cavity.

CONTRAINDICATIONS

The OSV II Lumbar Valve System should not be used in patients with non-communicating hydrocephalus.
This valve system should not be implanted when an infection along the shunt pathway (e.g. meningitis, ventriculitis, perito-
nitis) is suspected. It is advisable to postpone valve implantation if an infection is present anywhere in the body (septicemia,
bacteremia).
The OSV II Lumbar Valve System should not be implanted in patients with untreated choroid plexus tumors. Such tumors pro-
duce CSF at rates in excess of the specification of the flow regulation Stage II, and the OSV II Lumbar Valve System would under-
drain under these conditions.

SIDE EFFECTS

• In addition to the risks associated with shunt system or component implantation, major complications include mechanical
failure, such as tubing fracture, material deterioration with time, or shunt pathway obstruction, infection, immune system
reaction to materials and CSF leakage along the shunt pathway. System disconnection can lead to catheter migration into
the subarachnoid space or peritoneal cavity.
• Intracranial hypertension syndrome is a specific result of obstruction.
• Overdrainage may result in subdural hematomas, craniostenosis, intracranial hypotension syndrome, sunken fontanelles (in
infants) or acquired tonsillar herniation.
• Shunt system failure should be suspected if any of these is noted: Continuing symptoms of hydrocephalus; CSF leakage;
redness, tenderness or erosion of the skin along the shunt pathway. These complications require prompt replacement of the
shunt system or affected component(s).
• Low grade bacterial colonization may cause recurrent fevers, anemias, splenomegaly, shunt nephritis or pulmonary hyper-
tension.
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