Controlling Flow Rate in Post-Operative Pain Pumps

1. Mechanical Post Operative Pain Pumps Ways to Control the Flow Rate (Technical Presentation) April 2016

2. Parameters affecting the flow rate • Resistance; The resistance to medication flow is created by the “Restrictor”. • Pressure ; The medication pressure over the “restrictor” (the pressure difference between the inlet port and exit port of the restrictor ). Epidural 2

3. Reservoir Restrictor Represents pressure of 700 milibar Represents pressure of 0 milibar Schematic lay-out of common Elastomeric Pump טיפול בכאב מבוא ורקע כללי • The elastomeric reservoir creates the pressure of the medication. • The restrictor creates the resistance to the medication flow. In the above lay-out, the pressure tover he restrictor is the pressure in the pump reservoir, in this example is 700 milibar. 3

4. Flow-rate chart of typical Elastomeric Pump Flow-Rate Curve Pressure Curve טיפול בכאב מבוא ורקע כללי • Due to the characterizes of the elastomeric material , the pressure at the beginning and at the end of the therapy is higher then at the middle . • Therefore, the flow rate at the beginning and at the end of the therapy is higher then in the middle. Due to the characterizes of typicl elastomeric material the flow -rate chart of a typical elastomeric pump is always concaved! 4

5. Reservoir Flow Regulator with Pressure Compensation Mechanism Represents pressure of 700 milibar Represents pressure of 500 milibar Schematic lay-out of Elastomeric Pump with Pressure Compensation Inlet Port Secondary Chamber Restrictor טיפול בכאב מבוא ורקע כללי • The elastomeric reservoir creates the pressure of the medication. • The Flow Regulator maintains constant pressure difference between the inlet port and the secondary chamber. • The restrictor creates the resistance to the medication flow between the Inlet Port and the Secondary Chamber. The pressure over the restrictor such lay-out is the pressure difference between the inlet port and the secondary chamber of the regulator, in this example is 200 milibar. 5

6. Represents pressure of 700 milibar Represents pressure of 500 milibar Represents pressure of 900 milibar SmartBlock™ & SmartInfuser PainPump™ are the only Elastomeric Pump with pressure compensation mechanism Pressure Curve Flow-Rate Curve Despite the pressure changes in the elastomeric reservoir, the flow regulator maintains constant pressure difference that result with straight horizontal flow -rate chart. 6

7. Influence of the pressure at the exit port on the flow-rate of Elastomeric Pump The flow-rate of pumps with Pressure Compensation is Indifferent to the changes of the Pressure in the exit port The pressure at the pumps exit port influences the pressure over the restrictor it a typical elastomeric pump; reduce it.The pressure at the secondary chamber in the Pressure Compensation pump is significant higher then the pressure at the exit port; thus, no influence on the pressure over the restrictor. Presser Compensation Stable Flow Rate Typical Pump Low Flow Rate 7

8. Influence of changes in the barometric pressure on the flow-rate of Elastomeric Pump The flow-rate of pumps with Pressure Compensation is Indifferent to the changes of the Barometric Pressure The barometric pressure influence the pressure inside the elastomeric reservoir; higher barometric pressure results with higher medication pressure in the reservoir High Barometric Pressure Low Barometric Pressure Presser Compensation Presser Compensation Stable Flow Rate Stable Flow Rate Typical Pump Typical Pump High Flow Rate Low Flow Rate 8