Supplemental Body Plethysmograph Service Guide Version/Revision 1.A ComPAS ver. 1.9

Transcription

1 Supplemental Body Plethysmograph Service Guide Version/Revision 1.A ComPAS ver. 1.9 Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 1

2 Information in this manual is subject to change without notice and does not represent a commitment on the part of Morgan Scientific, Inc. The software described in this document is furnished under a license agreement. The software may be used or copied only in accordance with the terms of the agreement. It is against the law to copy the software on any medium except as specifically allowed in the license or nondisclosure agreement. No part of this manual may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, for any purpose without express written permission of Morgan Scientific, Inc. Copyright 2012 Morgan Scientific, Inc. Precautions Caution: Federal law restricts this device to sale by, or on the order of a physician Caution: Not suitable for use in the presence of flammable anesthetics Service of this instrumentation is restricted to factory trained personnel only Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 2

3 Table of Contents Chapter Section Details Page 1.0 Problem Guide Common problems with symptoms and solutions Diagnostics Body Box Diagnostic routines Changing Gas Cells 3-1 Replacing the O2 Cell Replacing the CO Cell Cleaning and Disassembling the Mouthpiece Shutter Assembly 5-0 Cleaning the Plethysmograph Cabin 4-1 General Recommendations Routine Practice Hygiene Cleaning Instructions Cleaning/Disinfecting- Recommendations Chart Disassembling the Pneumotachograph 15 Assembly 4-7 Disassembling the Valve and Shutter Assembly Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 3

4 1:0 Body Box Problem Guide Fault Symptom Solution The large inspirate bag will not empty for gas calibration The pump continues to run but the inspiratory bag will not empty. 1) Check the side gas analyzer absorber is seated properly. 2) Check that the gas cylinder output pressure is set to 50 psi 3) Replace the large inspirate bag. If the problem persists it is useful to try one of the small expirate bags to confirm that your spare large inspirate bag is leak free or not. 4) If you have completely ruled out any leaks in the bag, the problem will be resolved by adjusting the vacuum switch. This can be accessed on the rear of the box electronics module as shown: If the bag will not trigger the vacuum to indicate "empty", then turn the screw adjustment counterclockwise. Complete one full turn and try emptying the bag again. Continue until the vacuum trigger operates. No cylinder gas reaches the analyzers during calibration. The gas analyzers appear to be sluggish and the DLCO results are in error. The flow volume calibration will not be accepted after several attempts. Body Box appears to operate (i.e. valve functions and bag filling) with the exception of being able to calibrate the analyzers. System appears to be working, but the analyzer responses are slow. You may also notice that the inspirate and expirate bags are emptying simultaneously when only the expirate bag is supposed to be emptying. During the calibration sequence, the flow volume calibration is constantly rejected. The cylinder pressure is too high. Reduce the cylinder pressure to between 50 & 60 psi. Note: Sometimes old gas regulators do not display the correct pressure! Open the electronics module. It is very likely that a sample tube has been kinked or trapped. Check that the pneumotach is properly seated in the valve body. Check that the red and blue hose connections to the top of the pneumotach are connected properly. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 4

5 Fault Symptom Solution Communication is lost with the Body Box The analog flow signal appears to be working as do the digital controls, but all other analog channels are reading ) Administrative rights have been changed or taken away from ComPAS. In Regedit, set Full Administrative rights for the registry branch: HKEY_Local_Machine Software Morgan Scientific, Inc Navigate to C:\Program Files\Morgan Scientific\ and also the main program Full Administrative rights: C:\Program Files\Morgan Scientific\ 2) The Compatibility Mode properties for the ComPAS icon must be set to Windows XP Service Pack 3 for all users! Gas appears to be leaking from inside the electronics assembly. The cylinder of diffusion gas (model 5510) or compressed air (model 5500) is going down. When the main pressure is turned-off on the regulator, the gauge rapidly falls to zero. The AirTrol miniature precision regulator may have failed. Earlier models of Body Box 5500 and 5510 were fitted with a model 820 regulator. This should be replaced with the improved model 810. When received from Morgan Scientific, the output pressure will have been set to 50psi. Manometer fluid appears to climb when trying to calibrate Mouth Pressure. You cannot set zero on the manometer when trying to calibrate because the fluid keeps climbing. It is not possible therefore to calibrate Mouth Pressure. If you have not calibrated Mouth Pressure for some time, The problem would likely be seen as erroneous lung volume data. Typically a leak into the valve during a VTG maneuver will result in a falsely lower value for VTG, FRC and TLC. A low TLC value would most likely be recognized by an abnormally low RV (TLC -SVC= RV). One of the piston valves on the patient manifold is leaking and needs to be replaced. Please call Morgan Scientific for immediate help. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 5

6 Fault Symptom Solution No gas is collected in the expiratory bag at the end of a DLCO test. During either gas calibration or DLCO testing, the inspiratory bag will not inflate. All other test functions and valve operation seems to be normal. Items to check are as follows: 1) That the patient maintained a tight seal on the mouthpiece during expiration. 2) That the settings for Washout and Sample were appropriate. Note: Minimum setting for Sample is 400ml. Minimum setting for Washout is 200ml. 3) The cylinder pressure (used to operate the valves) is set at 50 psi. No gas is filling into the inspiratory bag. During either gas calibration or DLCO testing, the inspiratory bag will not inflate. All other test functions and valve operation seems to be normal. There is an over-pressure sensor that is used to prevent the inspiratory bag from being over-filled. The sensor shown in the illustration below has a screw adjustment on the side. A clockwise turn of the screw will decrease the sensitivity for detecting an over-pressure. The inspiratory bag is not filling with enough volume During DLCO tests, either too much or too little gas is entering the inspiratory bag. The control of the bag filling can be adjusted as follows: 1) Go to "Calibration" and then click on the Diagnostics button 2) From the side [Tabs] select "Configuration". The default setting for the "Inspirate Bag Filling Speed" is 18. Decreasing the value will increase the filling volume of the bag. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 6

7 Fault Symptom Solution The VA at BTPS values appear to be elevated. The VA (Alveolar Volume) at BTPS from the DLCO test are higher than TLC from either plethysmographic or helium dilution tests. 1) Assuming the TLC values are reliable and reproducible, the most likely cause is a minor leak in the expiratory bag. Sometimes the leak is so small that it cannot be detected by the vacuum switch test prior to completing any DLCO maneuver. 2) Check that the chemicals in the absorber are fresh. In particular, exhausted soda lime will cause significant changes in helium analysis. 3) Check that the absorber is not over-filled causing a leak. The gas analyzers are not calibrating properly from the inspiratory bag. If you did not recognize a problem in gas calibration, you may first see the symptom with erroneous Alveolar Volume values in DLCO. The helium analyzer wave form seen during calibration is clearly unusual (see diagram) The top coil of solenoid S-20 has failed and needs replacing. The flow/volume signal appears to have lost all gain. The flow signal can be zeroed but there was little or no gain when performing a test or calibration. The analog signals for the gas analyzers are normal. The internal differential pressure transducer has most likely failed. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 7

8 2.0 Body Box Diagnostics The diagnostics screen will show all the voltages coming from the Body Plethysmograph. At the same time, it will allow the service of biomedical engineer to test the digital control functions of the instrument. To access diagnostics, go to "Calibration" and then click on the Diagnostics button From here you will be able to view and check both the analog voltages and digital controls. The right-hand tabs provide an array of 'tools' and 'test functions' to help engineers with any service issues. Setup - is used for the initial installation of the Body Box and also for creating linearity tables and changing span factors in calibration. Gas - gives access to testing all functions where gas analysis is used. Digital - allows you to test all the digital commands and actions Modules - allows you to run any of the automated sequences used in testing Scope - provides a useful oscilloscope to view voltage changes Configuration - hardware control settings On all screens, the analog voltages can be viewed directly in the appropriate meter displays. To diagnose digital functions and Body Box solenoid operation, clicking on any of the Digital Controls will activate the command. The valve diagram will indicate which valve function is being activated by the "Change Valve" options. On the 5510, the valve has the following positions: Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 8

9 Patient to Atmosphere (the position for spirometry, flow volume and MVV studies) Patient to the Expirate Bag (activated in the DLCO test) Patient to the Inspirate Bag (activated in the DLCO test) Patient to Closed Shutter (used in VTG and Raw testing. Note: the "Shutter" button operates this position) Empty the Expirate Bag (also checks for any leaks) Empty the Inspirate Bag (also checks for any leaks) Fill the Inspirate Bag The [Configuration] tab allows you to change settings for both hardware function and test settings: Number of points to show on history reports DLCO % of VC to use for bag filling Number of points to show on history reports Gas sampling speed The default setting is 10 The number of past calibration dates to view on the calibration history displays The default setting is 100 The percent of measured VC to use when filling the bag for DLCO The default setting for the "Inspirate Bag Filling Speed" is 18. Increasing the value will reduce the volume of gas entering the bag and conversely, decreasing the value will increase the filling volume of the bag. The default setting is 0.6 L/min This is the pump speed for gas sampling and rarely if ever needs changing. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 9

10 Setting for oxygen zero Typically this value is very close to 4000 Flow noise filter The default setting is 3 This is a value that must be recorded (Set to Current) whenever the O2 cell is changed The filter is used in post processing of all flow data. Increasing the filter value will smooth data but care has to be taken not to affect peak flow readings. Mouth pressure calibration value The default setting is 20 cmh20 The value used when calibrating the mouth pressure transducer with a manometer. MIP MEP computation method The default setting is 0 Field not used at this time. AtoD Rev Body Box serial numbers after should all be set to 1 Swap A/B pistons on non- DLCO models Only used on a special research unit 3.0 Changing the O2 and CO Gas Cells 3-1 Changing the O2 Cell 1) Turn off the electronics and remove the power cord. 2) Remove the white O2 cell cap by simply pulling down. 3) Unplug the signal cable from the center of the sensor. 4) Unscrew the old O2 cell and replace with the new one; for now do not connect the signal cable to the O2 cell 5) Go to "Calibration" and then click on the Diagnostics button 6) From the side [Tabs] select "Configuration". Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 10

11 7) The current zero or open-circuit value will be shown. Click on [Set to Current] and be absolutely certain that you click the button! 8) Reconnect the O2 signal cable and replace the white cap over the cell. 9) Exit the diagnostics routines. 10) Once everything is replaced and the system has been powered-on, it is necessary to go to "Tools" and "Configuration" and "Devices" to tell the software that the cell(s) have been changed. Click the [Change] button to confirm the cell change. 11) Run a gas calibration to complete the cell change 3-2 Changing the CO Cell Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 11

12 1) Turn off the electronics and remove the power cord. 2) The CO sensor is mounted under the Body Box electronics module. 3) Pull off the large white cover. 4) Remove the plug and then unscrew the three retaining screws. 5) Once the new cell has been replaced, you will need to go to "Tools" and "Configuration" and "Devices" to inform ComPAS that new cells are being used. Click the [Change] button to confirm the cell change. 6) Run a gas calibration to complete the cell change 4.0 Cleaning and Disassembling the Mouthpiece Shutter Assembly Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 12

13 4-1 General Recommendation To reduce the risk of cross infection a new Bacterial Viral Filter should be used for each subject. A Risk Assessment should be carried out to assess the risks presented to both operator and subject, and an action plan devised by the facility to minimize the chance of cross infection occurring, particularly where known-infectious or immuno-deficient subjects are being tested. An assessment should be made of methods of decontamination available to the operator and their effectiveness against potential risks - a table of materials used in the Plethysmograph is provided below to assist in this. It is recommended in cases of high risk with no effective disinfection methods available that the contaminated parts are disposed of; for this device, these are the Pneumotach Assembly (pneumotach complete), Filter Adaptor and Interconnection Assembly. 4-2 Routine Practice A new Bacterial Viral Filter should be used for each subject. Between patients it is recommended that all exterior surfaces of the Plethysmograph (pneumotach assembly and valve) by wiped down using Sani Surface Wipes. A delay of at least 5 minutes should be allowed between subjects to allow settling of previously aerosolized particles in the measuring device. It is recommended that the Pneumotach Assembly be regularly cleaned according to the guidelines of the user s facility. In the event of visible contamination to the Pneumotach Assembly and Screen - these should be cleaned and disinfected. The frequency of cleaning is dependent on the Facilities Risk Assessment, usage, and test environment, but should be at least monthly or every 100 subjects (500 blows). 4-3 Hygiene It is vital for the user to set guidelines for protective hygiene measures whilst performing spirometry testing. There are three main potential sources of cross contamination, skin contact; aerosolized particles and saliva/body fluids. By far the most important is the last item a minimum requirement is to use a new disposable mouthpiece for each subject tested. We recommend using the Bacterial Viral Filter for all testing maneuvers. We also recommend that a delay of at least 5 minutes be allowed between subjects. This allows aerosolized organisms to be removed by gravitational sedimentation between tests. (Am J Respir Crit Care Med Vol 159. pp , 1999). 4-4 Cleaning Instructions All parts of the Plethysmograph require regular cleaning, i.e. the removal of visible particulate contamination. The parts of the Plethysmograph that make up the Pneumotach Assembly also require disinfecting. Morgan Scientific recommends that cleaning and disinfecting should normally be carried out on a bi-annual basis. In addition to a weekly cleaning and disinfection cycle, Morgan Scientific recommends cleaning and disinfection of equipment to be carried out after use on infected subjects or prior to use on immunocompromised subjects. The user must determine what level of disinfection is appropriate and acceptable in any particular circumstance. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 13

14 4-5 Cleaning/Disinfecting- Recommendations Chart Part Material Clean/Disinfect Autoclave Recommended Disinfectants Main Cabin Exterior Cabin Frame: Aluminum AlMg3, Polyurethane & aliphatic setting paint Clean No Wiping w ith a 70% Isopropyl Alcohol impregnated cloth provides a suitable form of cleaning and low -level disinfection. Cabin Door: Toughened security glass Sani Surface Wipes are recommended and w idely used in hospital settings. Chair Patient Valve Cabin Panels: Acrylic Wood and polyurethane coating OR acrylic (two types of chair are available) Polyoxymethylene (POM), Aluminum Clean No As Above Clean No As Above Interconnection assembly Nylon Clean No As Above Filter Adaptor Polyoxymethylene (POM) Clean Viable As Above Pneumotach Body Polyoxymethylene (POM) Clean Viable As Above Pneumotach Screen Aluminum, Stainless Steel Clean & Disinfect O Rings Viton fluoroelastomer Clean & Disinfect Viable Viable Disinfect by immersion in sodium dichloroisocyanurate solution at 1000ppm concentration of free chlorine for 15 minutes. The pneumotach screen w ill also w ithstand autoclaving at 134 C for 3 minutes. As Above Inspirate & Expirate Bags Polyoxymethylene (POM), Polyethylene Dispose No Dispose Definitions of cleaning and disinfection are as defined in Sterilization, Disinfection and Cleaning of Medical Equipment: Guidance on Decontamination from the Microbiology Committee to Department of Health Medical Devices Directorate, 1996 Recommendations for chemical disinfectants are derived from the PHLS publication Chemical Disinfection In Hospitals On the Body Box, the complete breathing pathways can be cleaned and sterilized. The full circuit includes the following components: The pneumotachograph assembly The patient valve Cleaning guidelines for each module will now be detailed: Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 14

15 4-6 The Pneumotachograph Assembly Step 1 Disconnect the heater cable and the red and blue hoses from the pneumotach. Carefully remove the pneumotach from the patient valve. Step 2 Place your thumbs on the two pressure fittings and gently turn against one another in an anti-clockwise direction. If the pneumotach is a later design, a special tool is available to help open the two halves. This will open the pneumotach and gain access to the Lilly-style screen. Up against a backlight, carefully examine the screen. Some bacterial/viral filters deposit a fine lint that can gradually clog the screen. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 15

16 Step 3 If the screen needs simple cleaning, preferably blow compressed air or O2 through the screen. If compressed air is not available, hold the screen beneath warm running water. Shake the screen vigorously to remove water droplets and then let it air dry before re-assembling the pneumotach. With each Plethysmograph there are spare screens to use while others are drying. If the screen needs to be sterilized, disinfect by immersion in sodium dichloroisocyanurate solution at 1000ppm concentration of free chlorine for 15 minutes. The pneumotach screen will also withstand autoclaving at 134 C for 3 minutes. Step 4 Once all the parts are cleaned and sterilized, apply a small amount of DuPont Krytox grease on the two O'ring seals that secure the pneumotach back into the patient valve. Krytox is available from Morgan Scientific: Cat No. CH71686 Krytox grease (1 oz) 4-7 The Valve and Shutter Assembly Step 1 Turn-off the cylinder pressure and use the diagnostics screen in ComPAS to bleed-off any pressure in the circuit. Remove the inspirate and expirate bags. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 16

17 Step 2 Disconnect the all the tubing connections. Each of the pneumatic tubing connections are labelled for correct re-assembly. To release the high-pressure connections, hold the collar against the manifold and pull on the hose. Regular soft hose connections simply pull away from the retaining nipple. Step 3 Remove the valve assembly from the patient arm. The valve simply slides out of the retaining slot Step 4 The valve can be further disassembled by removing the inspirate bag valve as shown. The valve body should either be cleaned with 70% Isopropyl Alcohol or immersed in Cidex as recommended by the manufacturer. Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 17

18 Step 5 Once the valve has been cleaned, it should be lubricated using the Krytox grease before use. The parts to lubricate are all the visible the O-rings. Step 6 Each of the pressure and tubing connections are labelled on the valve body with corresponding labels on the tubes. The pneumotach connections are labelled with red and blue identifiers. Having put everything back together, use the ComPAS Diagnostic screen to test that all the valve functions are performing properly. 5-0 Cleaning the Plethysmograph Cabin Since the Plethysmograph is designed to be an 'open' and friendly environment, the majority of the construction is made of glass and acrylic. These materials tend to show dirt and dust very easily, so we recommend that the instrument be cleaned on a regular basis. Cabin Exterior All the glass or acrylic surfaces should be cleaned with a commercial glass cleaner using a soft cloth or paper towel. For the interior panels, we recommend a glass cleaner that also contains a disinfectant or bacterial fighting agent. Having cleaned the interior panels, the door should be left open and the cabin ventilated for 20 minutes. Materials Data: Exterior Frame: Alluminium AlMg3 Frame Covering: Polyurethane & aliphatic setting paint Door: Toughened security glass Panels: Acrylic Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 18

19 Cabin Interior The cabin chair and floor surfaces should be cleaned with a commercial cleaning solution that contains a mild disinfectant or bacterial fighting agent. Having cleaned the interior, the door should be left open and the cabin ventilated for 20 minutes. Materials Data: Chair: Wood and polyurethane coating OR acrylic (two types of chair are available) Chair Post: Stainless Steel 3041 and 3161 Floor: Synthetic rubber (non latex) Morgan Scientific, Inc. Supplemental Body Plethysmograph Service Guide Page 19