BREAS MEDICAL
PV401 Service Manual Issue K-2
Service Manual
136 Pages
Preview
Page 1
TABLE OF CONTENTS
Service Manual PV401
TABLE OF CONTENTS 1.
INTRODUCTION...1 1.1 1.2 1.3 1.4 1.5
Intended use of the ventilator... 1 Design and function of the ventilator... 1 The scope of this manual... 1 Intended audience ... 1 Service personnel's training requirements... 1
2.
OPERATING MANUAL (Reference copy)
3.
MAINTENANCE SERVICE INSTRUCTIONS ...1 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9
4.
REPLACEMENT PARTS...1 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8
5.
Pneumatic Diagram ... 1 Functional Block Diagram... 2
DISMANTLING AND ASSEMBLING THE PV 401 ...1 6.1 6.2 6.3 6.4 6.5 6.6
7.
General view ... 1 Casings and decals... 2 Drive unit... 3 Exploded view A, Motor and Transformer ... 4 Exploded view B, Casing and Base Plate ... 5 Exploded view C, Circuit Boards and Connectors ... 6 Exploded view D,.Bellows and Drive Screw ... 7 Part No. list... 8
FUNCTIONAL DIAGRAMS 5.1 5.2
6.
Verifying the components and software installed... 1 Special safety precautions ... 1 Equipment and tools required ... 1 Replacement parts required... 1 Servicing instructions... 2 Service schedule ... 2 External checks ... 3 Internal checks ... 4 Final checks before handing over ... 6
Tools required... 1 Removing the upper casing ... 1 Replacing the LCD board... 2 Removing the motor unit from the lower casing ... 3 Replacing the complete motor unit... 4 Assembling the motor unit in the casing... 6
MOTOR UNIT...1 7.1 7.2 7.3 7.4 7.5 7.6
Doc. No.1525En
Construction ... 1 Inspecting/Replacing the drive belts... 2 Lubricating the drive screw ... 2 Replacing the membranes in the check valves ... 3 Tubes and bellows, leakage check... 6 Replacing the drive screw assembly ... 7
Issue: K-2
BREAS MEDICAL
Page 1
Service Manual PV401
8.
ELECTRONICS ... 1 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 8.10 8.10 8.11 8.12
9.
Function and construction...1 Wiring diagram, test points...6 Main cabling diagram ...7 Test points...8 Calibration of pressure sensors...9 Check of battery operation...11 Replacing the alarm batteries ...12 Electrical safety precautions...14 Upgrading the software...15 Upgrading the software to revision MXG...16 Circuit diagrams ...18 Component positions...28 Component list ...33
FAULT TRACING ... 1 9.1 9.2
Fault tracing ...1 Error codes...3
10. APPENDICES 10.1 10.2 10.3 10.4
Page 2
Engineering Change History PV 401...1 Service Record For PV 401...1 Returning Products To Breas...1 Breas Addresses ...1
BREAS MEDICAL
Doc. No. 1525En
Issue: K-2
Service Manual PV 401
1 1.1
INTRODUCTION
INTRODUCTION Intended use of the ventilator
The PV 401 is a pressure-controlled, pressure-monitored ventilator, especially developed for treatment in the home of patients with chronic breathing difficulties. The PV 401 is designed to give many years of trouble-free breathing assistance to the user provided that preventive maintenance is done at the specified intervals described in this manual. Well-performed maintenance will increase the service life of the ventilator considerably. It is also important that any peripheral equipment and accessories are checked at the time the service is carried out.
1.2
Design and function of the ventilator
The PV 401 is constructed around a bellows and a drive screw assembly driven by an electronically-controlled servo-motor. A microprocessor controls the correct speed of the motor and its power supply by means of calculations based on the settings for pressure, rate, inspiration time etc. The set pressure and the trigger level are monitored at the same time. In the event of a mains power supply fail, the ventilator will automatically switch to the external battery supply. This is indicated by the LED in the On/Off button flashing. If the external battery voltage drops too low, an audible alarm is given.
1.3
The scope of this manual
The manual contains all the points to be checked during the maintenance service and other service instructions for the PV 401. Also included are reference copies of the Operating Manual and the Patient Data Analysis Manual.
1.4
Intended audience
This Service Manual is intended for technicians who have medical/technical training and knowledge of the construction and function of the ventilator. It is not intended for clinic personnel or patients. Breas Medical reserves the right to make changes to the product and the contents of this manual without prior notice.
1.5
Service personnel's training requirements
Thanks to the simple construction of the PV 401, no special competence is required other than general medical technical training on ventilators. Always contact Breas Medical if there are any questions or if training is required. All service must, however, be performed as described in this manual.
Doc. No. 1525En
Issue: K-2
BREAS MEDICAL
Page 1
INTRODUCTION
Page 2
Service Manual PV 401
BREAS MEDICAL
Doc. No. 1525En
Issue: K-2
Operating Manual PV 401
Operating Manual PV 401
CONTENTS 1
INTRODUCTION...1
2
IMPORTANT SAFETY NOTICES ...2
3
INSTALLATION ...3 3.1 3.2 3.3 3.4 3.5 3.6 3.7
4
PANEL DESCRIPTIONS...5 4.1 4.2 4.3 4.4
5
Unpacking... 3 Placement ... 3 Connecting the tubes... 3 Mains power supply ... 3 Replacing the fuse... 4 Power cord... 4 External battery power ... 4
Front panel... 5 Setting panel description... 6 Rear panel description ... 7 Underside description... 8
DETAILED FUNCTION DESCRIPTION...9 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8
On/Off button and External battery operation ... 9 Checking the software version ... 9 Function button... 9 Decrease/Increase and Selection buttons... 10 Lock function... 10 Setting Date and Time... 10 Alarms ... 11 PCV & PSV Modes ... 12 5.8.1 PCV (Pressure Control Ventilation) Mode ... 12 5.8.2 PSV (Pressure Support Ventilation) Mode... 13 5.8.3 Comparing PCV and PSV ... 14
5.9
Settings... 15 5.9.1 Setting a parameter value ... 15 5.9.2 Pressure... 15 5.9.3 Alarm for low Pressure... 15 5.9.3.1 Setting the alarm level for Pressure... 16 5.9.4 Rate ... 16 5.9.5 Inspiration time... 17 5.9.6 Trigger... 17 5.9.7 Plateau ... 18 5.9.8 Expiratory sense (EXP. SENSE) ... 18 5.9.9 Tidal volume (Est. Vol.) ... 19 5.9.10 Alarm for low Tidal Volume... 19 5.9.10.1 Setting the alarm level for low Tidal Volume ... 19
5.10 Incorrect settings ... 20 5.11 Digital Output (D-sub, female) ... 20 5.12 Analog Output (D-sub, male) ... 21
BREAS MEDICAL
Doc. No. 1602EN Issue: M-1
Operating Manual PV 401
6
FUNCTION CHECKS ... 22 6.1
Function check in PSV (Pressure Support Ventilation) mode...22 6.1.1 6.1.2 6.1.3 6.1.4 6.1.5 6.1.6 6.1.7 6.1.8 6.1.9
6.2
Function check in PCV (Pressure Control Ventilation) mode ...24 6.2.1 6.2.2 6.2.3 6.2.4 6.2.5 6.2.6 6.2.7 6.2.8
7
Adjustment of the mask and patient circuit...28 Settings in PSV mode ...28 Settings in PCV mode ...28
BATTERY OPERATION... 29 8.1 8.2
9
Alarm check PATIENT – low pressure ... 25 Inspiration... 26 Exhalation ... 26 Trigger... 26 Tidal volume (EST. VOL.) ... 26 Alarm check for low Tidal volume ... 26 Alarm check POWER ... 27 Completing the function check ... 27
USAGE ... 28 7.1 7.2 7.3
8
Alarm check “PATIENT” – low Pressure... 22 Inspiration... 23 Exhalation ... 23 Trigger... 23 Expiratory sense (EXP. SENSE) ... 23 Tidal volume (EST. VOL.) ... 23 Alarm check for low Tidal Volume ... 24 Alarm check for Power failure... 24 Completing the function check ... 24
External Battery...29 Low battery voltage alarm ...29
OXYGEN CONNECTOR... 30
10 CLEANING, FILTER REPLACEMENT AND SERVICE... 31 10.1 Cleaning/replacing the air filter ...31 10.2 Yearly service ...31
11 FAULT TRACING ... 32 11.1 Fault tracing chart...32
12 ACCESSORIES ... 33 13 TECHNICAL SPECIFICATIONS PV 401 ... 34 14 PNEUMATIC DIAGRAM ... 35 15 PATIENT INSTRUCTIONS FOR BREAS PERSONAL VENTILATOR PV 401... 36 PATIENT SETTINGS ... 37
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BREAS MEDICAL
Operating manual PV 401
1
INTRODUCTION
INTRODUCTION
The PV 401 is a pressure controlled and pressure support ventilator. It has two modes of operation; PSV and PCV. Both modes have an adjustable trigger sensitivity setting which allows the patient to initiate ventilator-assisted breaths. In PSV mode (Pressure Support Ventilation), the ventilator’s expiratory sense can also be adjusted allowing the ventilator to more easily match each patient's needs. In PCV mode (Pressure Controlled Ventilation) the ventilator provides assisted/controlled breathing.
Explanation of label symbols under the ventilator: Read the Operating Manual thoroughly before connection to the patient.
Body floating.
Class II equipment; dual isolation.
0123
CE marking applies according to the directive MDD 93/42/EEC.
TÜV approved according to IEC 601-1, EN 794-2.
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IMPORTANT SAFETY NOTICES
2
Operating manual PV 401
IMPORTANT SAFETY NOTICES
• The PV 401 should not be used for total life support. Use BREAS PV 501 instead. • Clinic personnel and patients must read this operating manual and understand how the PV 401 works before setting up and using the ventilator. • Adjustments to settings may only be carried out by authorised clinic personnel. • Before use, a function check must be performed. • To ensure maximum operational reliability, the PV 401 must be serviced at the specified intervals by authorised service personnel. • Oxygen may only be supplied through the patient hose, use BREAS oxygen adapter. • Do not use the PV 401 in environments where there are explosive gases or other inflammable anaesthetic agents present. • Do not use patient hoses or tubes made of static or electrically conducting material. • Electromagnetic fields greater than 10 V/m can affect operation. Examples of equipment that produce electromagnetic fields are defibrillators, diathermia equipment, cellular telephones, etc. • Do not use a steam autoclave to sterilise the ventilator. • The ventilator’s performance may deteriorate at temperatures below 5°C and above 50°C. • Do not place the PV 401 on soft surfaces so that the air inlet on the underside can be blocked. • Always clean all parts that come in contact with the exhalation air before use on a new patient. • If an air humidifier is used, always place it lower than the PV401 to prevent water from running into the ventilator if the humidifier tips over.
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Operating manual PV 401
3
INSTALLATION
3.1
Unpacking
INSTALLATION
• Check the ventilator for any damage and that all ordered accessories are included.
3.2
Placement
• Place the PV 401 on its feet, on a hard, flat surface. Make sure that nothing can block the patient air inlet under the ventilator.
3.3
Connecting the tubes
• Connect the patient circuit (A) to the “PATIENT AIR” outlet on the front panel. • Connect the thin tube (B) for the exhalation valve to the “EXH. VALVE” nipple. • Connect the pressure measuring tube (green) (C) to the “PRESSURE” connector. • If a bacteria filter/oxygen adapter (D) is used, connect it between hose (A) and the patient air outlet. PAT IEN T A IR B
Exh. Valve Pressure
A
D
C
3.4
Mains power supply
• IMPORTANT! Make sure that the power cord is undamaged before it is connected to the ventilator. • P O W E R S U P P LY
POWER
P OW ER
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Check that the voltage selector is set for the voltage the ventilator is to be connected to. Different countries have different power supplies, the USA has, for example 115 V. All European countries have 230 V. Voltage range 115 V covers 110 – 120 V Voltage range 230 V covers 220 – 240 V
To change the voltage setting • Make sure the power cord is not connected. •
Change by turning with a screwdriver.
•
Change to the correct fuse rating.
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INSTALLATION
3.5
Operating manual PV 401
Replacing the fuse • Check that the power supply fuse the set voltage.
2
has the correct rating for
For 230 V, use a glass fuse F 315 mAL For 115 V, use a glass fuse F 630 mAL
1
• Change the fuse by pulling the fuse holder straight out. There is a spare fuse in the holder.
3.6
Power cord • Connect the power cord to the power socket BREAS power cord.
. Only use a
• Secure the power cord in the clip to prevent accidental disconnection.
3.7
External battery power
See Chapter 8 for complete information.
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Operating manual PV 401
4 4.1
PANEL DESCRIPTIONS
PANEL DESCRIPTIONS Front panel
PATIE N T A IR EX H. VA LVE
PR ES SUR E
2
1
3
(1)
Patient air outlet, ∅ 22 mm ISO cone, male.
(2)
Exhalation valve connector, ∅ 4 mm tube.
(3)
Connector for pressure measuring at the exhalation valve, ∅ 3 mm tube (green).
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PANEL DESCRIPTIONS
4.2 (1)
Operating manual PV 401
Setting panel description Patient pressure meter; 0 to 40 mbar/cm H2O.
P R E S SU R E
1 0
(2) (3) (4)
Rate setting; Breaths per minute (BPM). Inspiration time setting; in seconds (only active in PCV mode.)
(5)
Trigger setting; green LED is lit during a patient triggered inspiration.
(6)
Plateau setting; the time to reach the set pressure.
(7)
10
Patient pressure setting; Green LED is lit during inspiration.
Expiratory sense setting; percentage of maximum flow. (Only active in PSV mode.)
20 30 m b ar / c m H 2 O
40
14
2 3 4 5 6 7 8
PRE SSUR E 6 R AT E .
40
6
40
.INS P. TIM E 0 .5 T RIGG E R
5
m b ar B PM S ec
O F F, -2
m b ar 8
10
80
0
1 .8
P LAT E AU
E ST. V O L .
9
% L ite r
+
O N /O F F
11
A LA R M POWER PATIE NT
12
Est. Vol. The tidal volume delivered is 13 displayed here after each breath. The alarm level setting function for Pressure and low Tidal Volume is also accessed here.
(9)
- and + buttons to increase or decrease the selected parameter. The buttons are also used to set the date and time and to make selections in different displays.
P SV M O DE PCV
(10) ON / OFF switch; Keep pressed for 2 seconds to start or stop the ventilator. (11) Alarm for power failure; red LED lights if the mains or external battery supply fails. An audible alarm is also given. (12) Patient alarm. The red LED flashes if the set percentage of the set pressure is not reached within 15 seconds, e.g. due to leakage from the mask and/or the tidal volume is low. An audible alarm is also given together with a flashing arrow indication against the function in question (Pressure and/or Est. Vol) in the display. (13) Button for changing between PSV (Pressure Support Ventilation) and PCV (Pressure Control Ventilation) mode. Keep pressed for 1 second to change mode. (14) Seven LED indicators showing which function is selected. The selection function's parameter can be adjusted using the –/+ buttons (9). (15) Function button. Used to select required parameter or to mute audible alarms for 2 minutes. (16) Green LED, when lit, indicates that the setting panel is locked. (17) LCD Display. Shows the current settings. It is also used when setting the Date & Time. The background lights when button (15) is pressed and stays on for 2 minutes after the last press on a setting button.
BREAS MEDICAL
16 17
10
(8)
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Operating manual PV 401
4.3
PANEL DESCRIPTIONS
Rear panel description
1
2
P O W E R S U P P LY
O P E R ATIO N H O U R S
3
4
PO W ER
D IG ITA L O U T P U T
A N A L O G O U TP U T
FUS E
5
6
E X T. B AT TE R Y
FUS E
9
10
8
7
(1)
Connection for power cord.
(2)
Hour meter, shows the ventilator's total operation time.
(3)
Buzzer for alarm. Adjust the sound level using a small screwdriver.
(4)
Fastening clamp for power cord.
(5)
Voltage selector switch; 115 V or 230 V AC.
(6)
Fuse holder with fuse, T 630 mA for 115 V, T 315 mA for 230 V.
(7)
Analog signal output for registering patient pressure and tidal volume, male.
(8)
Digital communication connector, female.
(9)
Socket for external battery, 24V DC.
(10) Fuse holder with fuse for external battery supply. F 3.15 A.
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PANEL DESCRIPTIONS
4.4
Operating manual PV 401
Underside description
2
1
(1)
Air inlet and filter for patient air. See Chapter 10 for replacing/cleaning the filter.
(2)
Model and serial number label.
Explanation of symbols on label: 1 2
3
4
5
6
7
(1)
Model number.
(2)
Serial number.
(3)
Class II equipment; dual isolation.
(4)
Body floating.
(5)
Read the Operating Manual thoroughly before using with the patient.
(6)
CE marking applies according to the directive MDD 93/42/EEC.
(7)
TÜV approved according to IEC 601-1, EN 794-2.
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Operating manual PV 401
5
DETAILED FUNCTION DESCRIPTION
DETAILED FUNCTION DESCRIPTION
5.1
On/Off button and External battery operation The green LED shows a steady light when the ventilator is operating from the mains supply. The LED flashes when operating from an external battery.
O N /O F F
Press and hold the button for 2 seconds to switch on or off. The ventilator should be kept connected to the mains supply, even when not in use, to maintain charging of the alarm batteries.
5.2
Checking the software version
PR ESS URE
REV
R AT E
m b ar B PM
INS P. T IM E
401
se c
T R IG G E R
M XG
m b ar
P LAT E AU :
SGP
When switching on the ventilator, the software version installed is shown for approx. 1 second before the ventilator starts working. The illustration shows an example of how the software version designation can appear.
% E S T. V O L.
5.3
Liter
Function button This button is used to: Select the parameter to be adjusted This button is used to select the required parameter to be set. A lit green LED indicates which parameter is active. If no setting is done within 5 seconds, the selected parameter LED will go off. Mute the acoustic alarm This button is also used to mute acoustic alarms for two minutes.
PR ESS URE
Y 97 m b ar
R AT E
M 12 B PM
INS P. T IM E
D 07 se c
T R IG G E R
m b ar
P LAT E AU :
Select Date & Time If this button is held while switching on the ventilator, the current date & time is shown in the display. See section 5.6, Setting Date and Time, for more information
H 13 M 34 %
E S T. V O L.
Liter
Pressing the function button will light the background illumination of the display.
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DETAILED FUNCTION DESCRIPTION
5.4
Operating manual PV 401
Decrease/Increase and Selection buttons These buttons have two functions. They are used to adjust a parameter setting, press – to
+
decrease or + to increase the value of the selected parameter. The new setting is saved in the ventilator’s memory at the first breath after the value has been set. The buttons are also used to set the date and time and as Yes/No selection buttons when setting the alarm levels for pressure and tidal volume, where + = Yes and - = No.
5.5
Lock function The lock function is used to lock the setting panel to prevent accidental changes to the settings.
1
+
5.6
is on, the lock is active. It is now only When the LED possible to switch the ventilator On or Off. Press and hold both the – and + buttons for 5 seconds to lock or unlock.
Setting Date and Time
As part of the data storage function, the date and time is recorded to allow analysis of the patient data in the different printouts available. Note! The clock function uses the 24-hour clock standard. To check or set the date and time:
PR ESS URE
Y 97 m b ar
R AT E
M 12 B PM
INS P. T IM E
D 07 se c
T R IG G E R
m b ar
P LAT E AU :
Page 10
The display will now show the current settings for date and time.
H 13 M 34 %
E S T. V O L.
• Press and hold the Function button while pressing the On/Off button.
Liter
To change a setting: • Press the Function button until the LED for the required setting is lit. • Press + to increase the setting or - to decrease it. • Continue by moving down through the menu to the M setting. • To exit this display, press the Function key after the M setting has been selected.
BREAS MEDICAL
Doc. No. 1602EN Issue: M-1
Operating manual PV 401
DETAILED FUNCTION DESCRIPTION
The display will now show the following text. PR ESS URE
m b ar
R AT E
B PM
INS P. T IM E
se c
T R IG G E R
m b ar
TU R N
P LAT E AU :
O FF POWER
E S T. V O L.
5.7
• Switch off the ventilator. The new date and/or time will be saved.
% Liter
Alarms
Power (red LED) Should the power supply fail during operation, the ventilator will alarm by the red LED for “POWER” being lit and an audible alarm. Attempts to start the ventilator without any power source connected will also cause this alarm.
A LA R M POW ER PAT IE N T
Patient (red LED) The patient alarm (red LED) flashes if the set percentage of the set pressure is not reached within 15 seconds, e.g. due to leakage from the mask and/or the tidal volume is low. An audible alarm is also given together with a flashing arrow indication against the function (Pressure and/or Est. Vol) in the display.
A LA R M POW ER PAT IE N T
The alarm is reset once the pressure and/or the tidal volume reaches the set value. Alarm for low Pressure The alarm for low pressure can be set as required. Refer to section 5.9.3, Alarm for low Pressure, for information. Alarm for low Tidal Volume The alarm for low Tidal Volume can be set as required. Refer to section 5.9.10, Alarm for low Tidal Volume, for information. Alarm mute The alarm can be muted for 2 minutes by pressing the Function (alarm mute) button. The alarm for low tidal volume can also be adjusted, see 5.7.7.
Alarm sound level Adjust the sound level of the alarm to a suitable level. Adjust the screw ( in figure) on the ventilator’s rear panel using a small screwdriver.
1
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DETAILED FUNCTION DESCRIPTION
5.8
Operating manual PV 401
PCV & PSV Modes
This section describes the PCV and PSV modes. The ventilator always starts in the mode which was active when it was switched off. • To change between PSV and PCV mode, press the MODE button for one second.
PSV MODE PCV 5.8.1
PCV (Pressure Control Ventilation) Mode
In PCV mode, the ventilation is controlled by the ventilator. The RATE setting corresponds to the patient’s breathing rate expressed as the number of breaths per minute (BPM). The length of each inspiration is controlled by the INSPIRATION TIME setting. The PLATEAU parameter sets the speed at which the pressure increases to the set value. The lower the setting, the slower the pressure increase will be, a higher setting will give a faster pressure increase and therefore a longer plateau.The setting has 9 steps where 1 is the lowest and 9 is the highest. The figure below shows how the Pressure and Flow settings control the ventilator's function in PCV mode, where the Pressure setting is 20 cm H2O, the Inspiration Time is 1.8 seconds and the Plateau setting is 5. A breath is started when either the set rate starts a breath or the patient triggers a breath (if trigger is activated). The ventilator tries to reach and maintain the set pressure until either the inspiration time setting expires or the bellows reaches its end position. Pressure cm H O 2
20
P atient ex hales
P re ss ure s etting
P lateau s etting
S tart of b re ath
seconds
In sp.tim e P C V
Flow % 1 00 %
M ax flow a nd s et p res s ure is reac hed
P atient ex hales
seconds
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Operating manual PV 401
5.8.2
DETAILED FUNCTION DESCRIPTION
PSV (Pressure Support Ventilation) Mode
In PSV mode, the patient normally controls both inspiration through the trigger function, and exhalation by the expiratory sense. If the patient’s own “triggering” ceases, the ventilator’s rate setting will take over where the RATE setting corresponds to the patient’s breathing rate expressed as the number of breaths per minute (BPM). The PLATEAU parameter sets the speed at which the pressure increases to the set value. The lower the setting, the slower the pressure increase will be, a higher setting will give a faster pressure increase. The setting has 9 steps where 1 is the lowest and 9 is the highest. The figure below shows how the Pressure and Plateau (Flow) settings control the ventilator's function in PSV mode, where the Pressure setting is 20 cm H2O, the Expiration Sense is 25% and the Plateau setting is 5. A breath is started when either the patient triggers a breath (if trigger is activated) or the set back-up Rate takes over. The ventilator tries to reach and maintain the set pressure until either the flow drops to the “EXP.SENSE” setting (percentage of maximum insp. flow), the bellows reaches its end position or Inspiration is longer than 3 seconds.
P re s s u re cm H O 2
P res su re setting
20
M ax . de livered press ure
S ta rt o f breath
s ec o n d s In sp .tim e P S V
F lo w % 10 0%
M ax . flow
E X P. S en se 2 5% se tting
F low h as dropped to s et E X P. S ens e. N ew brea th is triggered
P atient ex hale s
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s ec o n d s
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