VNS Therapy System Overview and Dosing

Transcription

1 Course Outline VNS Therapy System Overview and Dosing Product Overview Basic parameters and dosing Programming System set up Model 102/102R Dosing Diagnostics End of Service Common error messages Model 103/104 Dosing Diagnostics End of Service Common error messages Summary of differences Misc. Software Features Lessons Learned 2 VNS Therapy System Components Pulse Generators VNS Therapy Generators: Pulse Model 102/ Pulse Duo 102R Pulse Generator Demipulse Model 103/ Demipulse Duo 104 Pulse Generator Model 100, Model 101 (no longer distributed) Handheld Computer Dell Axim X50 VNS Therapy Programming Wand Model 201 VNS Therapy Model 250 Programming Software Version 7.1 Model 220 Magnets (Patient Kit) Leads Model 302 and 303 Lead (distributed) Model 300 (no longer distributed) Surgical Components (n/a for clinic setting) Model 402 Tunneler Model 502 Accessory Kit 3 Pulse Model 102 Pulse Duo Model 102R Demipulse Model 103 Demipulse Duo Model 104 Location Subcutaneously in left chest Purpose Delivers electric pulses at programmed time intervals Stores selected information Model 102 and 103 (Single Pin receptacle) Model 102R and 104 (Dual Pin receptacle) 4 1

2 Programming System Components VNS Therapy Leads Handheld Computer Platform for Programming Software Always keep charged when not in use Programming Wand Accessory to programming handheld computer Communication tool between Programming Software and Pulse Generator Lead Model 302 Perennia Model VNS Therapy Patient Magnets Inhibit Stimulation (all indications) VNS Therapy Patient Magnets-On Demand Stimulation (Epilepsy Only) Location Patient s wrist or belt Location Patient s wrist or belt Purpose Temporarily turn off the device to alleviate possible side-effects (due to stimulation parameters) Use Hold over device to immediately stop stimulation Keep in place for 65 seconds or greater After at least 65 seconds and when removed, stimulation resumes after one complete OFFtime period 7 Purpose To provide on-demand magnet mode stimulation before or at an onset of a seizure Can also be used to test device daily to ensure battery is functioning properly Details Magnetic field of at least 50 Gauss at 1 inch Apply or pass the Magnet over the Pulse Generator for >1 sec and <65 sec will result in magnet mode stimulation 8 2

3 Parameters NORMAL MODE BASIC PARAMETERS AND DOSING Pulse Generator Dosing Parameters Parameter Units Range Output Current Milliamps (ma) Signal Frequency Hertz (Hz) 1-30 Pulse Width Microseconds ( msec) Signal On-time Seconds (sec) 7-60 Signal Off-time Minutes (min) Stimulation throughout the day (24 hours/day, 7 days/week) is referred to as the Normal Mode Stimulation 10 Parameters MAGNET MODE Pulse Generator Dosing Parameters Parameters Dose Output Current (ma) Parameter Units Range Magnet Output Current Milliamps (ma) Magnet Pulse Width Microseconds ( µ sec ) Magnet On-time Seconds (sec) 7-60 The magnet output current will always be set to 0 ma for patients diagnosed with Treatment-Resistant Depression Pulse Width (µsec) 1 Signal Frequency (Hz) Output Current Amount of electrical current delivered in a single pulse of stimulation. Pulse Width Duration of a single pulse within a stimulation period Signal Frequency Number of pulses per second; measured in Hertz

4 Parameters Dose Adjustment Parameters Timing Patient 1 Patient 2 Stimulation Time Ramp Up On Time Ramp Down (2 sec.) (2 sec.) Adjusting Output Current alone. Output Current 1 ma 2 ma Adjusting Pulse Width alone. 250 msec 500 msec 1 Signal Frequency Pulse Width Off Time Ramp Up Gradual increase in output current over approximately two seconds at the beginning of stimulation. Adjusting Signal Frequency alone. 20 Hz 30 Hz 13 Ramp Down Gradual decrease in output current over approximately two seconds at the end of stimulation. 14 Parameters Timing - Duty Cycle Calculation Duty cycle (%) = On Time (sec) + 4 seconds X 100 On Time (sec) + Off Time (sec) OFF TIME (Minutes) ON TIME (Seconds) PROGRAMMING SYSTEM Set-up

5 Dell AXIM x50 Dosing System Set-up Getting Started Wand Check Flash Card Slot Notice: Only 1 connection into Handheld Serial Cable Stylus Handheld Computer A/C Adapter Model 201 Programming Wand Briefly press and release the two red Reset buttons Check illumination time of green Power Light Illumination > 25 seconds indicates sufficient battery life Power LED Reset Buttons Illumination < 25 seconds, replace 9 Volt Battery Getting Started Handheld Turn Handheld ON Place Programming Wand over patient s generator ( 1 inch away) Pulse Model 102/102R Generator: Dosing ON/OFF 19 5

6 Typical Dose Adjustment Session 1. Interrogate generator 2. Adjust parameters if desired, based on efficacy, outcome and paying attention to patient s tolerability 3. Program parameters 4. Always interrogate generator as last step in session Ensures parameters are programmed as desired System and Normal Mode Diagnostics steps will be added to dose adjustment sessions once minimum stimulation parameters are achieved Step 1 Interrogate Device Interrogation is always the first and last step in a programming session From Main Menu, select Interrogate Device Step 1 Interrogate Device (cont.) With wand properly placed over the generator, select Start Interrogation Step 2 Selecting Parameters Tap the New button for the parameter you want to change. Allow time for completion

7 Step 2 Selecting Parameters (cont.) Tap the desired value Use scroll buttons to view more selections Step 3 Programming Select Program then Start Programming Step 3 Programming (cont.) Step 4 Final Interrogation (cont.) NOTE: After completion the device will stimulate the patient as programmed. Note: For patients with depression, the pulse generator s magnet mode output should remain at 0 ma Check parameters are programmed as desired, then, Select Menu followed by Main Menu, and turn handheld Off

8 Example of Titration Process Parameter Step #1 Step #2 Step #3 Output current Signal Frequency 20/30 20/30 20/30 Pulse Width 250/ / /500 Signal ON Time Signal OFF Time Example of Titration Process: cont. Parameter Step #4 Step #5 Step #6 Output current Signal Frequency 20/30 20/30 20/30 Pulse Width 250/ / /500 Signal ON Time Signal OFF Time Magnet Output Current Magnet Pulse Width Magnet Signal ON Time.5 (0 ma for TRD).75 (0 ma for TRD) 1.0 (0 ma for TRD) Magnet Output Current Magnet Pulse Width Magnet Signal ON Time 1.25 (0 ma for TRD) 1.5 (0 ma for TRD) 1.75 (0 ma for TRD) Step #3 diagnostic tests should be routinely performed when the output current reaches 0.75mA and greater 29 Step #3 diagnostic tests should be routinely performed when the output current reaches 0.75mA and greater 30 Normal Mode Diagnostics: Model 102/102R Pulse Model 102/102R Generator: Device Diagnostics Normal Mode Diagnostic To assess the deliverability of the normal mode output current. Minimum settings: Output Current 0.75 ma Signal Frequency > 10 Hz ON Time 30 seconds Recommend perform at every office visit once patient can tolerate minimum settings (see above) 32 8

9 System Diagnostics: Model 102/102R Purpose: Tests the VNS system s connection to the patient and integrity of the VNS Therapy Lead Automatically programs the device to the following settings: 1 ma, 20 Hz, 500 msecs, 30 sec ON, and 60 min OFF, then returns the device to its original Normal Mode parameters Recommend perform at every office visit (pending patient s tolerance of settings listed above) OTHER DIAGNOSTICS Generator Diagnostics Only used to troubleshoot in the operating room on the day of implant. DO NOT use for Follow-up visits. Magnet Mode Diagnostics (For patients with Epilepsy) Tests the system s magnet mode functionality in the same way as the Normal Mode, but with the use of the magnet to initiate the test Typical Dose Adjustment Session 1. Interrogate generator 2. Adjust parameters if desired, based on efficacy, outcome and paying attention to patient s tolerability 3. Program parameters 4. Perform System and Normal Mode Diagnostics 5. Always interrogate generator as last step in session Ensures parameters are programmed as desired Perform Normal Mode Diagnostics Confirm device settings meet the requirements for this test Minimum requirements: Output Current 0.75 ma Signal Frequency > 10 Hz ON Time 30 seconds

10 Perform Normal Mode Diagnostics Select Menu Select Device Diagnostics Perform Normal Mode Diagnostics Select Other Diagnostics Select Normal Mode Diagnostics Perform Normal Mode Diagnostics Place programming wand over generator, select OK. Normal Mode Diagnostics RESULTS Output Status: If OK - Programmed current is being delivered If LIMIT Programmed output current is NOT being delivered DC DC Converter: Ranges from 0-7 DCDC 7 typically coincides with a LIMIT Output Status

11 Comparison of Possible Results NORMAL MODE DIAGNOSTICS Output current being delivered Implanted Communication mm/dd/yy OK Output current not being delivered Implanted Communication mm/dd/yy OK Perform System Diagnostics Select Menu Select Device Diagnostics Output Status OK Output Status LIMIT Output Current 2.0ma Output Current 2.0ma Lead Impedance OK Lead Impedance HIGH DCDC Converter 5 DCDC Converter 7 Near End of Service NO Near End of Service NO See troubleshooting section for High Lead Impedance on a diagnostic Test at Follow-Up Visit in Physician s Manual for recommendations and course of action Perform System Diagnostics Choose System Diagnostics from the Diagnostics Menu of options. Place programming wand over device, select OK. System Diagnostics RESULTS Lead Impedance: OK If OK integrity of the system is WNL DCDC (0-3) coincides with OK impedance. Lead Impedance: HIGH If HIGH lead impedance is higher than expected DCDC (4-7) coincides with HIGH impedance conditions (e.g. fibrosis or lead break) Output Status: If OK 1mA current is being delivered If LIMIT 1mA current is NOT being delivered

12 Comparison of Possible Results System Diagnostics 1 ma being delivered Typical discontinuity results Implanted Communication Output Status Output Current Lead Impedance mm/dd/yy OK OK 1.0ma OK Implanted Communication Output Status Output Current Lead Impedance mm/dd/yy OK LIMIT 1.0ma HIGH Suspected Lead Breaks If diagnostics suggest that a fracture is present, consider turning the VNS Pulse Generator to zero milliamps (0 ma) of output current. Continuing stimulation with a fractured Lead may result in dissolution of the conductor material resulting in Pain Inflammation Vocal Cord dysfunction DCDC Converter 3 Near End of Service NO DCDC Converter 7 Near End of Service NO Risk/Benefit of leaving On should be evaluated and monitored by the treating medical professional. See troubleshooting section for High Lead Impedance on a diagnostic Test at Follow-Up Visit in Physician s Manual for recommendations and course of action Pulse Model 102/102R Generator: End of Service End of Service (EOS): 102/102R Clinical Indicators of potential EOS Increase in seizure activity Painful or erratic stimulation Report of decreased perception of stimulation or no stimulation when performing daily magnet activation If EOS has been reached, the pulse generator will not deliver any output, the patient will not feel stimulation, attempts to interrogate will be unsuccessful 48 12

13 End of Service (EOS): 102/102R Elective Replacement Indicator (ERI): Upon Interrogation, if the ERI is set to YES, this message will be displayed. The ERI should be used as the primary indicator of nearing EOS. The time from ERI to EOS is highly dependent on the programmed parameters and the Lead impedance. End of Service: All Diagnostics (102/102R) Each diagnostic test will provide the ERI, Near End of Service. NO indicates the device is NOT nearing End of Service at this time. YES indicates the device is nearing End-of Service. Prompt replacement may help minimize any possible relapse in seizures/depressive symptoms. Note: Model 100B generators (distributed prior to 1999) do not have the Elective Replacement Indicator function End of Service Summary: 102/102R For help in determining generator battery life, please contact Clinical Technical Support at with the patient s complete parameter history and latest System Diagnostic test results If longevity of the generator is shorter than expected, contact Clinical Technical Support at Pulse Model 102/102R Generator: Common Errors 51 13

14 Output Warning Common Diagnostic Errors: 102/102R Communication problems during a diagnostic test can result in the following messages 53 See Troubleshooting Section in Physician s Manual for recommendations and course of action 54 Common Interrogation Errors Communication problems during an interrogation can result in the following messages Solutions to Common Errors Be sure the handheld computer is fully charged and is not plugged into a wall outlet. Test the batteries in the programming wand. Make sure the programming wand is directly over the pulse generator. Check all cables and connections to ensure they are properly connected. Rule out an EMI (electromagnetic interference). If these steps do not address the problem, call Cyberonics Clinical Technical Support Team at (866) See Troubleshooting Section in Physician s Manual for recommendations and course of action

15 Cross-Programming What is it? Cross programming one patient s settings to another patient s device without interrogating the second patient s device first. There have been a few incidences of cross-programming reported recently. Cross-Programming What can be done to prevent cross-programming? Always Interrogate as the first and last step Set Inactivity Time-out to a lower value (3 min, 5 min, or 10 min) for Prescribing Physician Handheld When does it occur? If the patient previously interrogated has the same model number generator and the software is left on either the program new parameters screen or a diagnostic testing screen. What will happen? The programming event will appear in the programming software as if it was performed on the first patient, though it was actually performed on the second patient Typical Dose Adjustment Session Pulse Model 103/104 Generator: Dosing 1. Interrogate generator 2. Adjust parameters if desired, based on efficacy, outcome and paying attention to patient s tolerability 3. Program parameters 4. Perform System Diagnostic Test 5. Always interrogate generator as last step in session Ensures parameters are programmed and delivered as desired 60 15

16 Step 1 Interrogate Device Interrogation is always the first and last step in a programming session From Main Menu, select Interrogate Device Step 1 Interrogate Device (cont.) With wand properly placed over the generator, select Start Interrogation Allow time for completion Step 2 Selecting Parameters Tap the New button for the parameter you want to change. Step 2 Selecting Parameters (cont.) Tap the desired value Use scroll buttons to view more selections

17 Step 3 Programming Select Program then Start Programming. Step 3 Programming (cont.) NOTE: After completion the device will stimulate the patient as programmed. NOTE: For patients with depression, the pulse generator s magnet mode output should remain at 0 ma Step 4 Final Interrogation (cont.) Example of Titration Process Parameter Step #1 Step #2 Step #3 Output current Signal Frequency 20/30 20/30 20/30 Pulse Width 250/ / /500 Signal ON Time Signal OFF Time Check parameters are programmed and delivered as desired, then, Select Menu followed by Main Menu, and turn handheld Off. Magnet Output Current Magnet Pulse Width Magnet Signal ON Time.5 (0 ma for TRD).75 (0 ma for TRD) 1.0 (0 ma for TRD) A System diagnostic tests should be routinely performed at each dosing 68 17

18 Example of Titration Process: cont. Parameter Step #4 Step #5 Step #6 Output current Signal Frequency 20/30 20/30 20/30 Pulse Width 250/ / /500 Signal ON Time Signal OFF Time Pulse Model 103/104 Generator: Device Diagnostics Magnet Output Current Magnet Pulse Width Magnet Signal ON Time 1.25 (0 ma for TRD) 1.5 (0 ma for TRD) 1.75 (0 ma for TRD) A System diagnostic tests should be routinely performed at each dosing 69 Automatic Lead Impedance Measurement Impedance value will display the true impedance between 7000 Ohms and >10000 Ohms if High, and <200 Ohms if Low. Typical Dose Adjustment Session 1. Interrogate generator 2. Adjust parameters if desired, based on efficacy, outcome and paying attention to patient s tolerability 3. Program parameters 4. Perform System Diagnostic Test 5. Always interrogate generator as last step in session Ensures parameters are programmed and delivered as desired Once every 24 hours a lead impedance measurement is taken. If the impedance has reached High or Low between interrogations (office visits), a warning message similar to the one above will be displayed upon interrogation of device

19 System Diagnostics: Model 103/104 System Diagnostic Evaluates the Lead impedance of the VNS system as well as the pulse generator s ability to deliver the programmed stimulation. Recommended at every office visit. System Diagnostic for Demipulse Model 103/104 When output current is > 0 ma (e.g. Follow-up) 1. Short 0.25 ma, 130 msec pulse (Assess Impedance) 2. Followed by ANY programmed parameters (Assess Output Current) When output current is = 0 ma (e.g., in OR) : 1. Short 0.25 ma, 130 msec pulse (Assess Impedance) 2. Followed by 1.0 ma, 20 Hz, 500 msec parameters (Assess Output Current) Note Automatic System Diagnostic (one per 24 hours) is not performed when the Demipulse is programmed to 0mA System Diagnostics: Follow-up Assessing Lead Impedance Model 103/ / 104 Results Focus on Lead Impedance and Impedance Value 0.5 ma 0.5 ma 0.5 ma > 7000 ohms is High impedance for Demipulse Model 103 and ma 0.25 ma, 130 m sec Impedance Measurement Pulse The System Diagnostic assesses both the Lead Impedance and the Output Current for 103 and 104 All programmable settings are allowed 75 > 10,000 ohms is indicative of a discontinuity or break < 200 ohms is Low impedance for Demipulse Model 103 and 104, could also indicate a break or short circuit NOTE: In this example, 0.5 ma was programmed as the output current prior to diagnostics

20 Assessing Output Current Model 103/104 Focus on Output Current and Current Delivered Model 103/104 Comparison of Possible Results System Diagnostics Implanted 1 ma being delivered Typical discontinuity results mm/dd/yy Implanted mm/dd/yy Output current should be OK Communication OK Communication OK If LOW, then Current Delivered Programmed Current Output Current Current Delivered OK 1.0 ma Output Current Current Delivered LOW 0.0ma Lead Impedance OK Lead Impedance HIGH NOTE: In this example, 0.5 ma was programmed as the output current prior to diagnostics. 77 Impedance Value 3000 ohms End of Service x yrs Impedance Value ohms End of Service x yrs See troubleshooting section for High Lead Impedance on a diagnostic Test at Follow-Up Visit in Physician s Manual for recommendations and course of action 78 System Diagnostics Suspected Lead Breaks If diagnostics suggest that a fracture is present, consider turning the VNS Pulse Generator to zero milliamps (0 ma) of output current. Continuing stimulation with a fractured Lead may result in dissolution of the conductor material resulting in Pain Inflammation Vocal Cord dysfunction Risk/Benefit of leaving On should be evaluated and monitored by the treating medical professional

21 OTHER DIAGNOSTICS Generator Diagnostics Only used to troubleshoot in the operating room on the day of implant. DO NOT use for clinic follow-up visits. Pulse Model 103/104 Generator: End of Service Magnet Mode Diagnostics (For patients with Epilepsy) Tests the system s magnet mode functionality in the same way as the Normal Mode, but with the use of the magnet to initiate the test. 81 End of Service (EOS): 103/104 Clinical Indicators of potential EOS Increase in seizure activity Painful or erratic stimulation Report of decreased perception of stimulation or no stimulation when performing daily magnet activation If EOS has been reached, the pulse generator will not deliver any output, the patient will not feel stimulation, attempts to interrogate will be unsuccessful Generator Battery Life Projection The Demipulse Model 103 and 104 have the ability to project battery life based on time of implant and programmed settings. Each generator s software monitors battery depletion. Upon interrogation, warning messages are displayed by the handheld software when the generator battery life is approaching or is past the projection for end of service. All VNS Pulse Generators eventually require surgical replacement as a result of battery depletion. Pulse Generator replacement does not, of itself, require Lead replacement unless a Lead discontinuity (break) is suspected

22 Generator Battery Life Projection Generator Near End of Service Warning Instant update to End of Service Projection when new device settings are chosen. Projection will update over time as well Generator Past End of Service Warning Pulse Model 103/104 Generator: Common Errors At this point the generator may or may not be delivering stimulation as intended

23 Output Warning Common Diagnostic Errors Communication problems during a diagnostic test can result in the following messages 89 See Troubleshooting Section in Physician s Manual for recommendations and course of action 90 Common Interrogation Errors Communication problems during an interrogation can result in the following messages Solutions to Common Errors Be sure the handheld computer is fully charged and is not plugged into a wall outlet. Test the batteries in the programming wand. Make sure the programming wand is directly over the pulse generator. Check all cables and connections to ensure they are properly connected. Rule out an EMI (electromagnetic interference). If these steps do not address the problem, call Cyberonics Clinical Technical Support Team at (866) See Troubleshooting Section in Physician s Manual for recommendations and course of action

24 VNS Therapy Pulse Generators Comparison Summary of Differences: Previous Pulse Generators vs. 103/104 Size Comparison of the Model 103 vs. the Model Feature Model 103 / 104 Enhancements Generator Battery Life Projection System Generator Battery Life Warning Message Smaller Size Direct Lead Impedance Measurement Automatic Lead Impedance Measurement Once Every 24 Hours Quicker Communication Parameter Retention Benefit Remaining generator battery life projected and displayed to assist with End of Service decision process. Displayed when battery life is within 6 months of the end of life projection to assist with End of Service decision process. Improve post implant cosmetics. No more DCDC codes. Impedance is measured directly and displayed to clinician to give accurate measurements (ohms). Warning message notification to clinician upon interrogation if impedance is High or Low. Faster patient dosing and diagnostics. Settings are not lost if generator is reset. 95 Generator Evolution The Demipulse Model 103 and 104 have a 48% reduction in Generator thickness and a 74% reduction in Generator volume compared with the Model 100, which has improved post implant cosmetics. Model 100 Thickness: 0.52 (13.2 mm) 31 cc Model (10.3 mm) 26 cc Model 102/102R 0.27 (6.9 mm) 14/16 cc Model 103/ (6.9 mm) 8/10 cc 96 24

25 VNS Therapy Pulse Generators Comparison Generator Model R Matching Lead Type Single Pin Dual Pin Single Pin Dual Pin Launch Year Thickness 7 mm 7 mm 7 mm 7 mm Volume 14 cc 16 cc 8 cc 10 cc Weight 25 gms 27 gms 16 gms 17 gms Battery Life* 6+ yrs 6+ yrs 6+ yrs 6+ yrs Computer Platform Handheld/ Laptop Handheld/ Laptop Handheld ONLY Handheld ONLY Software Miscellaneous Software Features *Predicted longevity at 2mA, 20Hz, 500µS, 10% duty cycle into a 4kOhm load. The dose settings impact how long the battery will last. For example, the battery may last for 3 years at a higher setting, compared with 8 years at a lower setting. For the full range of settings in relationship to battery life, see the Physician's Manual or the EOS Projection on the Handheld. 97 Programming Software Features Adjusting Date and Time Inactivity Timeout Feature Time Stamp It is very important that the date and time on the handheld are correct. All historical programming data is stored using the handheld date and time

26 Inactivity Timeout Warning Database Utility Feature Capability to view and print programming history database in an Excel spreadsheet Equipment needed: Flashcard Reader Not provided by Cyberonics Technical support for the Flashcard Reader is not provided by Cyberonics Personal PC Not provided by Cyberonics Database Utility Feature Located on the User Preferences Screen Database Utility Feature Exporting Files

27 Database Utility Feature Programming Software Features View Database Patient does not need to be present to perform View Database Remove Flashcard from Handheld Computer 2. Insert flashcard into a flashcard reader connected to a desktop computer 3. Open files PIExport, DiagExport, and MagExport in Microsoft Excel View Database VIEW PARAMETER HISTORY Select View Parameter History View Database VIEW DIAGNOSTIC HISTORY Select View Diagnostic History

28 View Database VIEW MAGNET HISTORY Select View Magnet History Parameters Screen Menu Select Standard Settings sets Output current to 0 ma and other predetermined parameters Program Patient Data Program Patient Data Allows user to enter patient ID and Implant Date. Should be performed in the OR. Display Device History Display Device History Allows user to view stored pulse generator information

29 Handheld Battery Charge Keep your handheld computer plugged in at all times when not in use PC Power Remaining status bar indicates charge remaining on handheld computer Parameters Screen Menu User Preferences Screen Miscellaneous Handheld Features 113 Soft Reset Press Reset button with Stylus for 5 seconds Perform during screen freeze Reset button Hard Reset Press Power button and Reset button simultaneously Perform only when soft reset does not resolve a screen freeze Power button Reset button Contacts button Note: When prompted, select the Contacts button

30 Hard Reset If the handheld computer has not been plugged in to an AC power for a period of time, the battery charge will completely deplete. When you plug in the AC power cord, the handheld computer will go through a hard reset. Steps during hard reset Hard Reset Steps during hard reset Hard Reset Steps during hard reset Hard Reset

31 Align Screen Press both buttons together to align screen Power button Lock Button Lock button located on left side Should remain in the UNLOCK position at all times Note: This screen align is not associated with a soft or hard reset. The screen align should be used to voluntarily align the screen when the screen is not aligned. Select button Handheld is locked, move button down to unlock Handheld is in the unlocked position with the button down Proper Handling of the VNS Programming System The VNS Therapy Programming System is designed to withstand normal wear and tear conditions for electronic devices Do not subject the Programming System to rough handling or abuse Lessons Learned Do not pull on data cables If adaptor cable must be disconnected from the Handheld, grasp the connector firmly and pull the adapter out Do not store or operate the Programming System with sharp bends in the data cables or adaptors. Avoid coiling cables into small diameters

32 Lessons Learned Having a clear understanding of the parameters will lead to intended dose adjustments. Always Interrogate as the FIRST and LAST step at every visit. Keep your Handheld computer plugged in at all times when not in use Always check the battery in the wand prior to use and keep a backup 9 Volt battery if necessary Pay close attention to all warning, error, and fault messages Routine diagnostic testing can prove beneficial in the long term The Technical Guide and Physician s Manual are valuable tools for any questions, concerns, and troubleshooting