Title of Guideline (must include the word “Guideline”
(not protocol, policy, procedure etc)
Author: Contact Name and Job Title
Directorate & Speciality
Date of submission
Explicit definition of patient group to which it applies
(e.g. inclusion and exclusion criteria, diagnosis)
Version
If this version supersedes another clinical guideline
please be explicit about which guideline it replaces
including version number.
Statement of the evidence base of the guideline – has
the guideline been peer reviewed by colleagues?
Evidence base: (1-6)
1
NICE Guidance, Royal College Guideline,
SIGN (please state which source).
2a
meta analysis of randomised controlled trials
2b
at least one randomised controlled trial
3a
at least one well-designed controlled study
without randomisation
3b
at least one other type of well-designed
quasi-experimental study
4
well –designed non-experimental descriptive
studies (ie comparative / correlation and
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5
expert committee reports or opinions and /
or clinical experiences of respected
authorities
6
recommended best practise based on the
clinical experience of the guideline
developer
Consultation Process
Ratified by:
Date: September 2016
Target audience
Review Date: (to be applied by the Integrated
Governance Team)
Guideline for High Frequency Oscillatory
Ventilation In Adult Critical Care
Dr Martin Beed Consultant in Intensive Care, Critical
Care, NUH
Dr Thea de Beer Consultant in Intensive Care,
Critical Care, NUH
Nikki Sarkar Deputy Sister, Critical Care, NUH
Clinical Support Division
Adult Critical Care
1/9/2010, Updated 1/10/2013
Updated 29/09/16
Critically ill adult patients with existing or developing
severe hypoxia
Excludes: children or neonates; high frequency
oscillatory ventilation used within theatres (currently
there is no facility for this to happen); high-frequency
JET ventilation
Version 2
Version 1 ID1655
Peer reviewed by: NUH Critical Care Consultants;
Critical Care Governance Group, Rob Furby
Equipment Lead for Critical Care, Fiona Branch
Divisional Education Lead .
Evidence base: (1-5)
1b at least one randomised controlled trial
3 well –designed non-experimental descriptive
studies (ie comparative / correlation and case
studies)
4 expert committee reports or opinions and / or
clinical experiences of respected authorities
All intensive care consultants
Senior ICU nursing staff
Cross-town guidelines group.
Critical Care Governance
Medical and nursing staff all adult critical care areas
01/10/2021
A review date of 5 years will be applied by the Trust.
Directorates can choose to apply a shorter review
date, however this must be managed through
Directorate Governance processes.
This guideline has been registered with the trust. However, clinical guidelines are guidelines only. The
interpretation and application of clinical guidelines will remain the responsibility of the individual
clinician. If in doubt contact a senior colleague or expert. Caution is advised when using guidelines
after the review date.
HFOV Guideline Revised Sept 16 review Sept 21
Page 1 of 36
High Frequency Oscillatory Ventilation in
Adult Critical Care
Guidance for the initiation, ongoing management and weaning of
high frequency oscillatory ventilation in adult intensive care
patients
Introduction:
High frequency oscillatory ventilation (HFOV) is a method of ventilating patients using
specialised equipment. Despite it being extensively used in the management of critically
ill patients (including adults, children and neonates) there are no clear-cut indications as
to which patients are most likely to benefit from it, the optimal method to which to use it,
and how and when to wean patients from HFOV back to standard methods of
ventilation.
These guidelines are intended to help identify patients who may be likely to benefit from
HFOV, and give guidance on how to set up the HFOV ventilator (the Oscillator), initiate
and manage the patient on HFOV, wean the patient from HFOV, and troubleshoot
complications which may arise whilst on HFOV.
There is only one type of HFOV ventilator (the Novalung Vision Alpha) available for use
in adult Critical Care within NUH. This guideline is for that ventilator.
Exclusions
This guideline is not intended to be applied to the following circumstances:
 Children or neonates requiring HFOV ventilation
 HFOV used within theatres (currently there is no facility for this to happen)
 High-frequency JET ventilation (not used within adult Critical Care in NUH)
 This guideline does not cover the Sensormedics ventilator.
Background
High frequency oscillation (HFOV) is as the term describes, mechanical ventilation that
employs a very high respiratory rate whilst delivering smaller tidal volumes than used in
conventional ventilation. Since its introduction it has become well established in
neonatal and paediatric patients. Only relatively recently have advantages in adult
patients been recognised. Despite this, research into the benefits of HFOV in adults has
not been consistent. This has resulted in much debate amongst clinicians when
considering its effectiveness in patients.
Recent studies have not identified benefits from HFOV, and one study has suggested
that there may even be increased mortality associated with its use in ARDS.
Nevertheless consensus opinion within the literature recognises that these studies have
limitations, and suggests that HFOV still has a role as a life-saving measure in patients
who have failed conventional ventilation and who would otherwise die. As a result the
use of HFOV within NUH is a consultant-only decision, initiated when other forms of
ventilation have failed or are about to fail.
HFOV Guideline Revised Sept 16 review Sept 21
Page 2 of 36
Mechanisms of HFOV
The role of HFOV is to achieve and maintain optimal lung inflation through maximum
alveolar recruitment, increasing functional residual capacity. This is achieved through a
continuous flow of gas producing a pressurised circuit. The gas is oscillated using a
driven piston with a diaphragm unit. This action produces a low tidal volume and a high
frequency which are actively delivered to the patient. The side effects of HFOV may
include cardiovascular instability and barotrauma from the high airway pressures.
Indications for use
The use of HFOV is currently reserved for patients unresponsive to standard ventilation,
or patients in whom standard ventilation is likely to become increasingly difficult requiring
high ventilation pressures or levels of oxygenation. Failure of CO2 removal in
conventional ventilation may also be an indication for HFOV.
The initiation of HFOV is a consultant-only decision.
Potential indications:
FiO2 > 60% and PEEP >10cmH2O
Peak inspiratory pressure >30cmH20
Patients in whom continuous neuromuscular blockade is required because of poor lung
compliance (but NOT as a result of patient/ventilator asynchrony
Persistent uncompensated extreme hypercapnia (PaCO2 >10kPa) despite ventilator
optimisation
Patients in whom prone
As an initial alternative to prone positioning
positioning would normally be Where there is a contra-indication to prone positioning
considered, either:
Where the patient has not responded to prone positioning
Where there have been complications associated with
prone positioning
Patients in whom severe
Trauma-induced hypoxia
respiratory failure is likely to
Viral-induced hypoxia (i.e. influenza pneumonitis,
become progressively more
varicella
pronounced, including:
Inhalational/lung injury associated with burns, chemical
pneumonitis)
exposure or toxic epidermal necrolysis
Pancreatitis-induced acute respiratory distress syndrome
(ARDS)
Patients with a persistent broncho-pleural fistula leak in whom standard ventilation
cannot be optimized.
optimised
HFOV Guideline Revised Sept 16 review Sept 21
Page 3 of 36
Contra-indications to use
There are no absolute contra-indications to the use of HFOV in adults but the following
should be considered relative contra-indications in whom HFOV may cause further
complications:
Relative contra-indications:
Patients with intracranial hypertension
Patients with pronounced airflow Severe bronchospasm / asthma
limitation,
Emphysema / restrictive lung disease
includingat
those
with of having an occult, untreated pneumothorax*
Patients
suspected
Patients at risk of barotrauma /
Recent chest trauma*
pneumothorax, including
Known lung bullae
Recent lung resection / chest surgery
Patients who are profoundly haemodynamically unstable
Patients allergic to multiple neuromuscular blocking drugs
* NB these patients may be considered for HFOV where an intercostal chest drain
has been inserted first
Hazards / Cautions
Complications associated with HFOV include:
Cardiovascular instability during the initial recruitment phase
Barotrauma / pneumothorax / tension pneumothorax
Complications associated with prolonged usage of neuromuscular blocking drugs
De-recruitment / mucous plugging
Hypocapnia (can normally be prevented with careful monitoring and adjustment)
Raised ICP
HFOV Guideline Revised Sept 16 review Sept 21
Page 4 of 36
Management of HFOV within critical care
HFOV ventilators
There is only one type of HFOV ventilator (the Novalung Vision Alpha) available
for use in adult Critical Care within NUH..
An overview of the ventilator, including instructions on how to set up
ventilator circuits, and basic control functions can be found in Appendix
One.
Definition of Settings (terminology)
HFOV ventilators do not use the same setting as standard ventilators, and slight
variations exist between different HFOV machines. The following is a brief
explanation of terminology:
SETTINGS
Mean Airway Pressure (MAP)
(measured in cmH2O)
DEFINITION
Recruits and maintains lung volume determining
the oxygenation
Frequency (ƒ)
(measured in Hertz. 1 Hz = 60
breaths/minute)
Opposite to conventional ventilation. Increasing
the frequency will decrease CO2 removal as the
piston displacement is decreased, in turn
decreasing the AMP and I Time.
Cycle Volume (measured in ml)
Changes in Cycle Volume will change the Adjustments will affect the tidal volume (seen by
an increased chest wiggle) and reduce CO2.
measured amplitude
Base Flow
(measured in L/min)
Amount of gas flow in the circuit.
Changes in Bias flow will alter MAP.
FiO2
Determines oxygenation.
Initiating HFOV ventilation
The transition from standard to HFOV ventilation requires that the patient is adequately
prepared. Patients will initially need to be on an FiO2 of 100% using standard
ventilation, and also fully paralysed with neuromuscular blocking drugs (with
accompanying sedation). During the change to HFOV a maximal ventilatory
recruitment manoeuvre will need to be performed.
This procedure has the potential to make the patient cardiovascularly unstable and
provision should be made to reverse any hypotension that occurs. Following the
initiation of HFOV, and once the patient has been fully recruited, a chest X-ray should
be performed.
A check list for preparation, instruction on how to perform a recruitment
manoeuvre and initial HFOV settings can be found in the summary
guidelines
HFOV Guideline Revised Sept 16 review Sept 21
Page 5 of 36
Continuing care of patients on HFOV ventilation
Whilst a patient is on HFOV specific ventilation guidelines should be followed.
These address the following issues:
Target parameters; how to adjust the ventilator to
adjust clinical response in the face of:
Hypercapnia
Hypocapnia
Hypoxia
Suctioning whilst on HFOV
Weaning of ventilation, and when to convert to standard ventilation
Trouble-shooting complications, including:
HFOV failure
Loss of “chest-wiggle”
Secretion retention
Suspected baro-trauma /
pneumothorax
Changes in amplitude requirement
On-going ventilation guidelines for a patient on HFOV ventilation can be found
in the Summary Guidelines later in this document
Audit and Competency
The care of patients requiring HFOV ventilation may require intermittent audit to
ensure that good practice is adhered to. A sample audit form for the initiation and
care of HFOV patients can be found in Appendix 2.
A competency package will be made available, and a competency document
required. A sample competency document for the initiation and care of HFOV
patients can be found in Appendix 3.
References:
1.
2.
3.
4.
Novalung VisionAlpha High Frequency Oscillatory Ventilation User Manual
HumiCare 200 Short manual Gruendler GmbH no date
Mehta S, et al. High Frequency Oscillatory Ventilation in adults. Chest 2004
Chan KPW, et al. High Frequency Oscillatory Ventilation for adult patients with
ARDS.
5. Chest 2007
6. Downar J, et al. Bench-to-bedside review: High-frequency oscillatory ventilation
in adults with acute respiratory distress syndrome. Critical Care 2006
7. Chan KPW, et al. Clinical use of high-frequency oscillatory ventilation in adult
patients with acute respiratory distress syndrome. Critical Care Medicine
2006
8. McLuckie A. High-frequency oscillation in acute respiratory distress syndrome
(ARDS). British Journal of Anaesthesia 2004
9. David M. et al. High-frequency oscillatory ventilation in adults with traumatic
brain injury and acute respiratory distress syndrome. Acta Anaesthesiologica
Scandinavica 2005
10. Ferguson ND, et al. High-frequency oscillation in early acute
respiratory distress syndrome. New England Journal of Medicine 2013
11. Young D, et al. High-frequency oscillation for acute respiratory distress
syndrome. New England Journal of Medicine 2013
12. Malhotra A, et al. High-frequency oscillatory ventilation on shaky ground. New
England Journal of Medicine 2013
HFOV Guideline Revised Sept 16 review Sept 21
Page 6 of 36
Summary Guidelines 1
High Frequency Oscillatory Ventilation
Management on Adult Critical Care
Preparation for HFOV
1. Ensure patient is
 Well sedated
 On FiO2 100% on standard ventilation
 Has fluid / inotropes available for treatment of hypotension
 Has size 8 or above endotracheal tube
o Consider changing tube if < size 8
o Check position of tube is above carina
o Consider shortening tube if appropriate
2. Give bolus & commence infusion of neuromuscular blocking drug
Take baseline arterial blood gas (ABG)
Initial HFOV settings (Novalung vision alpha)





FiO2 100%
Bias flow (base flow) 20 l/min
Mean airway pressure (MAP) to current +5cmH2O
Frequency (ƒ) 8Hz
Cycle volume 185ml
Initial recruitment manoeuvre

 Check ABG 10-15 mins after commencing HFOV
 If PaO2 <8 and MAP<50 cmH2O commence recruitment:
o Increase mean airway pressure (using mean) by 5cmH2O
o Wait 10-15 mins then recheck ABG
o If PaO2 <8 and MAP<50 cmH2O repeat recruitment
If mean arterial pressure drops after recruitment to <60mmHg:
o Decrease MAP by 5cmH2O
o Give fluids / vasopressors if appropriate then repeat recruitment
If PaO2 drops after recruitment
o Decrease MAP by 5cmH2O & repeat ABG
o If further drop in PaO2 discuss with consultant who may consider
holding at present levels or a rapid recruitment manoeuvre
If relatively cardiovascularly stable, but hypoxic, consider a rapid recruitment
manoeuvre (consultant only):
 Set static inflation pressure to 40-50 cmH2O
 Press the SV button for 30-60 seconds, monitoring SaO2, heart rate and blood
pressure
HFOV Guideline Revised Sept 16 review Sept 21
Page 7 of 36
Initial Management
After recruitment, once optimum mean airways pressure (MAP) attained
 If possible keep the patient at this level of MAP for approximately 4 hours
before weaning
 During this 4 hour window adjust oxygen as required for SaO2 88-95, and
optimise PaCO2 using guidelines below
On-going management – carbon dioxide removal
TARGET pH = 7.25-7.35
After recruitment monitor pH and adjust frequency (ƒ) and amplitude (power or
cycle volume depending on oscillator) as below until pH in target range
High pH
 pH > 7.35 / ƒ < 15Hz
increase ƒ by 1-2 Hz every 2 hours until pH in target
range
 pH > 7.35 / ƒ = 15Hz
decrease cycle volume by 5-10mls ( or amplitude by 510 cmH2O) every 2 hours until pH in target range
Low pH
 pH < 7.25: increase cycle volume by 5-10mls (or amplitude by 5-10 cmH2O)
every 2 hours until pH in target range
 pH < 7.25 & max. cycle volume (or amplitude 90 cmH2O): decrease ƒ 1-2Hz
every 1-2 hours
 pH < 7.25 & max. cycle volume (or amplitude at 90 cmH2O) and ƒ = 4: discuss
with consultant and consider
o exclude tube occlusion and/or removing potential deadspace
o inducing deliberate cuff leak
o consider increasing inspiratory time
o bicarbonate infusion
On-going management – oxygenation
TARGET PaO2 8-9 kPa (or SaO2 88-95%)
After recruitment repeat ABG every 15 mins until PaO2 in target range

If PaO2 > 9kPa (SaO2 >95%) decrease FiO2 by 5% every 5 mins

If PaO2 < 8 kPa (SaO2 < 88%) increase FiO2 by 5% and consider
repeating recruitment manoeuvre
Once PaO2 stable in target range repeat ABG every 2-4 hours and wean as
below:
Identify the FiO2 (%) / Mean Airway Pressure (MAP cmH2O) and follow instructions
reduce MAP by 2cmH2O every 2-4 hours until MAP
 100% / >38
 100%
reduce
cmH2O/ 38
38 cmHFiO
2O 2 by 5-10% every 2-4 hours until FiO2
 80%
cmH2O/ 38 cmH2O reduce
80% MAP by 2cmH2O every 2-4 hours until MAP
34 cmHFiO
2O 2 by 5-10% every 2-4 hours until FiO2
 80% / 34 cmH2O reduce
70%
 70% / 34 cmH2O reduce MAP by 2cmH2O every 2-4 hours until MAP
32 cmHFiO
 70% / 32 cmH2O reduce
2O 2 by 5-10% every 2-4 hours until FiO2
60% MAP by 2cmH2O every 2-4 hours until MAP
 60% / 32 cmH2O reduce
cmHFiO
 60% / 30 cmH2O 30
reduce
2O 2 by 5-10% every 2-4 hours until FiO2
50% MAP by 2cmH2O every 2-4 hours until MAP
 50% / 30 cmH2O reduce
24 cmHeither
 50% / 24 cmH2O reduce
2O MAP or FiO2 until FiO2 30% and
MAP 22cmH2O
Consider converting to standard ventilation once MAP =24 for 6-12 hours provided
severe hypercapnia not present
HFOV Guideline Revised Sept 16 review Sept 21
Page 8 of 36
Recording observations
The following observations should be recorded in the respiratory/ventilation section
of the 24HR Observation Chart
 FiO2
 Mean Airway Pressure (MAP)
 Base Flow
 Cycle Volume
 Amplitude
 Frequency (f) in Hz
 Presence of bilateral chest wiggle





Deliberate cuff leak protocol
Suction oropharynx
Set high pressure alarm to 55cmH2O
Increase bias (base) flow 5-10l/min until mean airway pressure increase by 5
cmH2O
Deflate cuff until mean airway pressure decreases by 5 cmH2O
Return pressure alarms to previous values
Other associated on-going care







Oscillator observations should be recorded hourly on the supplied
documentation
All oscillator patients should be 30-45 degrees head up where possible
All circuits must be humidified
Soft clamps should be available at the bedside in case the patient
needs to be disconnected from the oscillator
Patients on the oscillator should have a standard ventilator at the
bedside at all times
Neuromuscular blockade infusions should be stopped after the first 24
hours and the patient assessed – if large swings in mean airway pressure
occur (>5cmH2O) sedation should be increased. If this fails consider
increasing bias (base) flow by 5-10 l/min or re-starting neuromuscular
blockade infusions (reassess every 24 hours
Suctioning is usually not required in the first 24 hours and only rarely
required thereafter. If suctioning is required a recruitment manoeuvre
should be performed afterwards
Troubleshooting complications







Circuit won’t pressurise – check for a leak or damage to the circuit or humidifier.
Unexplained rise in amplitude - check for secretions or ETT obstruction
Unexplained fall in amplitude – exclude pneumothorax (if in doubt, X-ray)
Unilateral wiggle – exclude pneumothorax or tube movement
Decreased wiggle – exclude secretions or tube blockage
Fall in PaO2 – consider pneumothorax, air-trapping or blocked ETT
Hypotension – exclude pneumothorax or air-trapping
 Raise in PaCO2 – exclude blocked ET
HFOV Guideline Revised Sept 16 review Sept 21
Page 9 of 36
Summary Guidelines 2
How to set up the Novalung Vision Alpha HFOV ventilator
NB. This oscillator has no back-up battery, always
have an alternative means of ventilation (i.e. Ambu
bag) in case of power failure
If in doubt about any aspect of oscillator management
not covered in this guideline please refer to the user
manual (kept on ICU)
Setting up the circuit
Prior to using any tubing carefully check the following:
 Packaging intact
 Expiry date not exceeded
 Exclude any visible damage (cracks, holes, heater wire connection). If any part
of the circuit is damaged do not use it, use another circuit instead.
 Ensure all humidifier jacks and adapter cables are clean and dry
 Ensure oxygen (below Left) and air (below Right) hoses are connected
HFOV Guideline Revised Sept 16 review Sept 21
Page 10 of 36
Assembly
1 Place and lock diaphragm chamber
into the intended opening of the
ventilator
See ventilator IFU
Diaphragm chamber compartment
Warning
Be sure to lock the tab
Diaphragm chamber
set
Tab locked
2. Attach impedance valve to
diaphragm chamber and connect
impedance valve to impedance valve
port off the ventilator See ventilator IFU
Impedance valve port
Impedance valve
HFOV Guideline Revised Sept 16 review Sept 21
Page 11 of 36
3. Place and lock exhalation bacteria
filter to the exhalation port of the
ventilator Be sure to close the retainer
knob
See ventilator IFU
Bacterial filter compartment
Retainer knob
4. Set the humidification chamber to the
humidifier base. See humidifier and
ventilator IFU
5. Connect the ventilator gas outlet to
the impedance valve gas inlet by 40 cm
connecting tube
40 cm connecting tube
HFOV Guideline Revised Sept 16 review Sept 21
Page 12 of 36
6. Connect outlet of the impedance
valve to gas inlet of the humidification
chamber using 30cm humidification
chamber tube.
Warning
To avoid sterilization of the
impedance valve a filter can be
connected between the impedance
valve and the 30cm humidification
chamber tube. Be noted, that in this
event the system compliance will be
affected producing lower
amplitudes during HFO operation.
Filter to avoid impedance valve
contamination
NB: the impedance valve should be fitted with a retainer clip (shown above) to hold “5
o’clock” tubing in place – it will work without this clip, but is better with it in place.
THE RETAINER CLIP IS NOT DISPOSABLE – DO NOT THROW IT AWAY
7. Connect the dually heated tubing
system to gas outlet of the
humidification chamber.
HFOV Guideline Revised Sept 16 review Sept 21
Page 13 of 36
8. Prepare connection to exhalation
bacteria filter by connecting: Silicon
joint, one-way valve and straight 22M
connector to the dually heated tubing
system exhalation limb.
Warning
Be careful to set the one-way valve in
the right direction.
9. Connect exhalation limb to the
exhalation bacteria filter.
10 Set pressure monitor to the Y-piece
and to pressure monitor port in the
ventilator
Pressure monitor
Paw port
THE PAW LINE MUST BE HANGING OVER THE
SUPPORT ARM SO THAT WATER CANNOT BACKTRACK FROM THE PATIENT INTO THE MACHINE – IF
THIS HAPPENS THE MACHINE WILL FREQUENTLY
ALARM WHILST THE OSCILLATOR IS IN USE
HFOV Guideline Revised Sept 16 review Sept 21
Page 14 of 36
11. Connect the electrical
connections to the humidifier.
Connect the reservoir to the
humidification chamber AND
allow it to fill before turning the
humidifier on. Once the humidifier
is turned on it will fill some more.
See humidifier IFU.
F&P Temperature probe for MR850
humidifier 900MR869 or equivalent, and
Heater wire adaptor for RT series dual
heated breathing circuit 900MR805 or
equivalent.
12 Plug in and switch both power switches on prior to use
Main power switch
900MR869
Screen power switch
13. In case rainout becomes a persistent problem try to extend the inspiratory limb by
adding in the extra 30cm tube (included in the set) between the Y piece and the
temperature probe.
Initial machine calibration
The Vision Alpha will run through an automatic self-test and calibration at power-up
HFOV Guideline Revised Sept 16 review Sept 21
Page 15 of 36
Setting standard alarm settings
The standard alarm settings are pre-set in the NovaLung Vision Alpha and are designed
to alter with the ventilator settings (i.e. they are pre-set to alarm if values reach a
percentage above or below whatever ventilator settings are being used)
Warnings
 Do NOT use with anaesthetic agents (e.g. isoflurane in the AnaConda)
 Do not cover tubing (e.g. with blankets
 Ensure heated tubing does not remain in contact with the patient’s skin
 Do not reuse single use items, do not use items that are broken or cracked
 Ensure a minimum average gas flow of 3L/min (to avoid overheating)
If high inspired oxygen concentrations (≥70%) are used for a long period of time
(>72hrs) there is an increased risk of damage (and subsequent failure) of the breathing
circuit. This is likely to result in partial or complete inability to ventilate the patient. Due
to the high risk associated with routinely changing circuits in profoundly hypoxic
oscillated patients, it has been agreed that the need for oscillation will be assessed
daily after 72hours use.
HFOV Guideline Revised Sept 16 review Sept 21
Page 16 of 36
Appendix One
Detailed instructions relating to the Novalung Vision Alpha
Basic Control Functions
1
2
5
3
4
The Vision α®'s front panel is divided into the following sections according to their
operations.
(1)
(2)
(3)
(4)
(5)
NOTE:
LED bar graph
LCD
Normal ventilation (CMV) setup section
HFOV setup section
Operating mode selection section
When you turn ON the respirator, the ventilation conditions used for the
last operation take effect.
HFOV Guideline Revised Sept 16 review Sept 21
Page 17 of 36
2
3
4
5
18
6
7
19
20
21
17
22
23
24
1. External alarm indicator lamp
2. LED bar graph
3. Power failure lamp
4. Mute button
5. VCV button
6. Manual breath button
7. PCV button
8. Tidal volume setting dial
9. Inspiration flow rate setting dial
10. Inspiratory pressure setting dial
11. Inspiratory time setting dial
12. Breath rate setting dial
HFOV Guideline Revised Sept 16 review Sept 21
13.PEEP/CPAP pressure setting dial
14. Trigger level setting dial
15.PS pressure setting dial
16. Operation mode selector
dial
17.Supply oxygen
concentration setting dial
18.LCD
19.Parameter selector dial
([Select/Setting])
20.Cancel button
21.Parameter accept button
([Accept])
22.Oscillation frequency setting dial
23.Mean airway pressure setting
dial
24.Cycle volume setting dial
Page 18 of 36
1.Setting (Changing) the Respiration Type
1.1 With the [Operation Mode] switch on the front select either
CPAP or CMV (normal ventilation).
1.2 When the CPAP mode is selected, the selection isfinalized by
the [Operation Mode] switch so that the respirator immediately
enters the CPAP mode
1.3 To change the MV (normal ventilation) mode, press the [VCV]
or [PCV] button on the front panel as appropriate.
1.4 The LCD displays the message "Do you want to switch to
VCV? If so, press [Accept]. If not, press [Cancel]." Or "Do you
want to switch to PCV? If so, press [Accept]. If not, press
[Cancel]." When you accept the displayed mode change, the
Numerals in the fields for items related to the newly selected
mode are brightly illuminated. The numerals in the fields for
items related to the previously selected mode are greyed out.
NOTE: It is possible to preset the front panel settings so that they are greyed out
2. Setting (Changing) the Ventilation Mode
2.1 From the LCD, open the ventilation condition setup screen. To switch to the ventilation
condition setup screen from another screen, rotate the [Select/Setting] dial so that the blue
highlighting moves within the LCD. Select the [IMV Setup] key in the bottom bar and then
press the [Select/Setting] dial.
NOTE
The bottom bar is positioned at the bottom of the CD screen. It contains IMV setup, IMV alarm,
IMV data, waveform and Loop. Various set up items can be selected to perform setup to rotate
the [Select/Setting] dial to select a desired item then press the [Select/Setting] dial
HFOV Guideline Revised Sept 16 review Sept 21
Page 19 of 36
2.2.
Choose [A/C] or [SIMV], whichever is desired, and then press the [Select/Setting] dial
2.3. The LCD displays the message "Do you want to switch to A/C (or SIMV)? If so, press
[Accept]. If not, press [Cancel]. To apply the displayed change, press the [Accept]
button, which is located in the lower right-hand side of the LCD. To abort the displayed
change, press the [Cancel] button.
3. Setting (Changing) the Ventilation Conditions from the Front Panel
Rotating the dial for a clockwise increases the
setup item displayed numerical value. A
clockwise counter rotation decreases the
displayed numerical value. Each setting is
finalized when it is changed to a new
numerical value.
NOTE
The numerical values for setup items
irrelevant to the selected respiration type
are greyed out. However you can rotate the
dials to pre select setting that will take
effect after the respiration type changes.
The respiration condition setup items
which can be defined from the front panel
are described in the table below
HFOV Guideline Revised Sept 16 review Sept 21
Page 20 of 36
Parameter
Setting
range
Resolution
Factory
default
setting
Description
[Vt]
50 mL to
2500 mL
1 mL
500 mL
Tidal volume of mandatory
ventilation expressed as
BTPS.
[Flow rate]
3 to 140 LPM
1 LPM
30 LPM
Maximal inspiration rate
during 1- minute mandatory
VCV.
0 to 100 cmH2O
[Insp. press.]
1cmH2O
20cmH2O
Sets the inspiratory
pressure. The peak
inspiratory pressure is
obtained by adding the
PEEP pressure to this
setting.
Sets the period of time
during which the inspiratory
pressure is maintained
[Ti]
0.1 to 9.9 sec
0.1 sec
1 sec
[Breath rate]
1 to 80 BPM
1 BPM
12 BPM
[PEEP/CPAP]
0 to 35 cmH2O
1cmH2O
0cmH2O
Sets the PEEP/CPAP
pressure.
Flow rate trigger:
0.5 to 20 LPM
Flow rate trigger:
0.1/9.9 LPM:
0.1 LPM;
10/20 LPM:
1.0 LPM Pressure
trigger:
0.1cmH 2O
Type: flow rate
Flow rate: 3.0
Pressure: -2.0
1cmH2O
0cmH2O
When you select the flow
rate sensitivity the base flow
is set to a level that is
higher than the trigger level
setting by 3 LPM.
For the flow rate trigger, the
pressure trigger is
automatically set to -2 cm
H2O for backup purposes
.
Sets the P S pressure. The
actual PS pressure is
obtained by adding the
PEEP pressure to this
setting.
1%
21%
[Trigger level]
Pressure trigger: 0.1 to -20 cmH2O
0 to 100 cmH2O
[PSV press.]
[Supply
oxygen
concentration]
21 – to 100%
HFOV Guideline Revised Sept 16 review Sept 21
Page 21 of 36
Breath rate during 1-minute
Mandatory ventilation.
Sets the supply oxygen
concentration.
4 Setting (Changing) the Ventilation Conditions from the LCD
4.1 Selecting (Changing) a Setup Item
Rotate the [Select/Setting] dial to select a desired setup item and then press the [Select/Setting]
dial. The LCD then displays the message "Do you want to switch to XXX? If so, press [Accept].
If not, press [Cancel]. To apply the displayed change,, press the [Accept] button. To abort the
displayed change, press the [Cancel] button.
4.2. Changing the Setting
Rotate the [Select/Setting] dial to select a desired setup item, and then press
the [Select/Setting] dial. The LCD then shows a setting bar graph. Rotate the
[Select/Setting] dial to select a new setting.
To apply the setting change, press the [Accept] button. To abort the setting
change, press the [Cancel] button.
The setup items to be defined from the LCD are described in the table below.
HFOV Guideline Revised Sept 16 review Sept 21
Page 22 of 36
Respiration condition setup (LCD)
Item
Setting range
Resolution
Factory
default
setting
Description
Trigger
type
[Pressure
trigger]
[Flow rate
trigger]
Flow rate
waveform
[Decrescent]
[Rectangular]
Decrescent
Patient
type
[Child] [Adult]
Adult
[Rise time]
0.1 to 0.9 sec
0.1 sec
0.1 sec
[Expiration
recognition]
10 to 45% of
peak
flow rate
1%
25%
[Plateau]
0.0 to 2.0 sec
0.1 sec
0.0 sec
[Apnea
breath rate]
1 to 80 BPM
1 BPM
12 BPM
Flow rate
trigger
HFOV Guideline Revised Sept 16 review Sept 21
The pressure trigger and flow rate
trigger are to be set independently
of each other. When you change
the trigger type, the setting also
changes. The pressure trigger is
activated in accordance with the
pressure setting. Even when the
flow rate is high, the trigger does
not work if the pressure is not built
up.
The flow rate trigger is
activated in accordance with
the flow rate setting.
The trigger can be activated
even when the pressure is
extremely low.
Flow rate waveform for mandatory
VCV ventilation. If you change this
setting, the I:E ratio automatically
changes.
The spontaneous inspiratory time
upper limit alarm is set to 3.5 sec
when "Adult" is selected or 2.5 sec
when "Child" is selected.
Sets the inspiratory rise time. The
peak inspiratory pressure is
reached in the pre-selected rise
time, which is within the preselected inspiratory time. This
setting is applied to the inspirations
for both PCV ventilation and PSV
ventilation. Select an appropriate
setting in accordance with the
hardness of the patient lung.
It is assumed that the maximal
inspiration flow rate is 100%. After
the end of inspiration, expiration is
recognized when the flow rate is
between 10% and 45% of the
maximal inspiration flow rate.
Time for retaining the mandatory
VCV inspiratory pressure. When
inspiration terminates, expiration
does not start immediately, but the
high airway pressure is maintained.
This ensures that fresh air is
delivered to the end of each
pulmonary alveolus. Consequently,
the inspired gas distribution in the
lung improves so as to promote
blood oxygenation.
Sets the number of
ventilations per minute for
apnea backup.
Page 23 of 36
5. Ventilation Condition Limitations
5.1 The [Apnoea Breath Rate] setting cannot be lower than the [Breath Rate] setting. If the
breath rate setting is higher than the apnoea breath rate setting, the apnoea breath rate
setting automatically follows the breath rate setting and becomes equal to the breath rate
setting. However, if the breath rate setting is lower than the apnoea breath rate setting,
the apnoea breath rate setting does not follow or become equal to the breath rate setting.
If an attempt is made from the LCD to select an [Apnoea breath rate] setting that is
lower than the [Breath Rate] setting, the LCD displays the message "You cannot select
an apnoea breath rate setting that is lower than the breath rate setting." If this message
appears, press the [Accept] button to clear the displayed message, and then enter an
appropriate setting.
5.2 As regards VCV ventilation, you cannot select a breath rate, tidal volume, or ventilation flow
rate setting that provides an I:E ratio of greater than 3:1. If an attempt is made to enter an
unacceptable setting, the previous setting takes precedence.
When the last setting (e.g., breath rate) exceeds the above limit:
 If a setting entered from the LCD is concerned, the LCD displays the message
"(Example) The I:E ratio cannot exceed 3:1. Check the tidal volume, inspiration flow
rate, and plateau settings." In this instance, press the [Accept] button to clear the
displayed message, and then perform respiration condition setup again.

If a setting entered from the front panel is concerned, the LCD does not display the
above message. Further, the numerical value remains unchanged even when the
associated dial is rotated.
CAUTION
The above limit is also imposed on the apnoea breath rate. The apnoea breath rate
setting is higher than or equal to the breath rate setting. In reality therefore the limitation
depends on the apnoea breath rate
If you change the breath rate setting during a PCV operation to exceed the above limit
the tidal volume setting automatically decreases so that the I: E ratio is automatically set
to 3:1 or lower
5.3. As regards PCV ventilation, you cannot select a breath rate or inspiratory time setting that
provides an I:E ratio of greater than 4:1. If an attempt is made to enter an
unacceptable setting, the previous setting takes precedence.
When the last setting (e.g., breath rate) exceeds the above limit:
 If a setting entered from the LCD is concerned, the LCD displays the message
(Example) The I:E ratio cannot exceed 4:1. Check the inspiratory time setting. In
this instance, press the [Accept] button to clear the displayed message and then
HFOV Guideline Revised Sept 16 review Sept 21
Page 24 of 36

perform respiration condition setup again.
If a setting entered from the front panel is concerned, the LCD does not display
the above message. Further, the numerical value remains unchanged even
when the associated dial is rotated.
CAUTION
The above limit is also imposed on the apnoea breath rate. The apnoea breath rate
setting is higher than or equal to the breath rate setting. In reality therefore the limitation
depends on the apnoea breath rate
If you change the breath rate setting during a VCV operation to exceed the above limit
the inspiratory time setting automatically decreases so that the I: E ratio is automatically
preset to 4:1 or lower
6. HFOV
Rotate the operation mode dial to HFO.
Before a change, you can set the frequency, mean airway pressure, and stroke volume.
HFO base flow:
SI pressure setting:
MAP upper limit 1
MAP upper limit 2
MAP lower limit:
Amplitude upper limit:
Amplitude lower limit:
HFOV Guideline Revised Sept 16 review Sept 21
Intra-circuit steady flow setting
Deep respiration pressure setting
Upper-limit setting for mean airway pressure
Pressure release upper limit pressure setting
for mean airway pressure
Lower limit setting for mean airway pressure
Upper limit setting for oscillatory pressure
Lower limit setting for oscillatory pressure
Page 25 of 36
HFO DATA
HFO base flow
Amplitude
SI time
MAP
Steady flow setting display
Measured amplitude pressure
Manual deep respiration elapsed time
Measured mean airway pressure
The amplitude value differs from the value displayed by the LED bar graph. Since the
amplitude is an absolute value of oscillatory pressure, divide the numerical value by 2 and add
the obtained value to the mean airway pressure. The resulting numerical value is indicated
by the LED bar graph.
Cycle volume is dependent on HFOV frequency as described below
Frequency (Hz)
Max Cycle
Volume (ml)
5
350
6
285
7
240
8
205
9
180
10
160
11
144
12
132
13
119
14
109
15
100
HFOV Guideline Revised Sept 16 review Sept 21
Page 26 of 36
Appendix Two
Detailed troubleshooting instructions relating to the Novalung Vision Alpha
If you cannot think of an appropriate remedial action when an alarm is issued or if you think
that the respirator is faulty, first take proper care of the patient and then perform a
troubleshooting procedure as directed in the table below.
The table below merely lists the troubleshooting procedures to be performed for the respirator,
and does not take patient factors into consideration. Also, note that the troubleshooting
procedures are enumerated in an order that does not imply the probability or severity of
troubles.
Remedies for alarm conditions
Trouble
The airway pressure is
too high.
Probable cause
The expiratory side
respiration circuit is
clogged.
Fighting with the patient.
The tube in the trachea
is clogged.
Other
There is a leak in the
respiration circuit.
The inspiratory side
circuit is clogged.
The airway pressure is
too low.
The flow rate is too low.
The supply gas pressure is
too low.
Other
The respiration circuit is
clogged.
There is a leak in the
respiration circuit.
The CPAP/PEEP is
abnormal.
The power supply is
abnormal.
The supply pressure is
abnormal.
The ventilation
operation is stopped
due to an unduly high
airway pressure.
The flow rate adjustment valve
is faulty.
Other
The power plug is not
connected
to the outlet.
Power is not supplied.
The power cord is broken.
Other
The pressure difference
between the supplied oxygen
and supplied air is greater than
2
2 kgf/cm .
The supply pressure is
2
below 3 kgf/cm .
The circuit is completely
clogged.
The patient became
suddenly worse.
The respirator is faulty.
HFOV Guideline Revised Sept 16 review Sept 21
Remedy
Correct any bend or twist in the respiration
circuit. Remove water from the circuit. If
necessary, replace the circuit.
Take appropriate remedial action in
compliance with the doctor's instructions.
Remove a secretion, for instance, by
providing vacuum suction.
Call an emergency contact number.
Check whether the circuit is damaged. Also,
check that the circuit connections are
properly made.
Correct any bend or twist in the respiration
circuit. Remove water from the circuit. If
necessary, replace the circuit.
With the IMV operating control section, raise
the flow rate setting.
Confirm the supply gas pressure and
check for leaks.
Call an emergency contact number.
Correct any bend or twist in the respiration
circuit. Remove water from the circuit. If
necessary, replace the circuit.
Check whether the circuit is damaged. Also,
check that the circuit connections are
properly made.
Call an emergency contact number.
Call an emergency contact number.
Connect the power plug to the outlet.
Ensure that the commercial power supply
breaker and switch are ON.
Call an emergency contact number.
Call an emergency contact number.
Check the gas lines for improper
supply. The normal range is from 3.0
2
to 4.5 kgf/cm .
Check the supply gas lines for improper
supply. The normal range is from 3.0 to 4.5
2
kgf/cm .
Replace the respiration circuit.
Take appropriate remedial action in
compliance with the doctor's instructions.
Call an emergency contact number.
Page 27 of 36
Operating Control Abnormalities
Trouble
The mode remains
unchanged when
you change the
mode switch
position.
The oxygen
concentration is
unstable.
Probable cause
Remedy
The mode switch is faulty.
Call an emergency contact number.
Place the switch in the CPAP or CMV
(normal ventilation) position.
The mode switch is faulty.
The respirator is faulty.
Call an emergency contact number.
Other
Call an emergency contact number.
The supply gas
pressure is unstable.
Check whether there is a leak or clog in
the supply line.
The flow sensor is faulty.
Call an emergency contact number.
The mixer is malfunctioning.
Call an emergency contact number.
Other
Call an emergency contact number.
During IMV/CPAP Operation
Trouble
Probable cause
There is a leak in the
respiration circuit.
The peak
inspiratory
pressure does not
rise.
The inspiratory side
circuit is slightly
clogged.
The flow rate is too low.
The supply gas pressure
is too low.
Other
The trigger level setting is too
high.
Automatic triggering
takes place.
Synchronization is not
achieved.
There are many leaks.
Improper triggering is invoked
by
a collapsed or bent patient
circuit.
The respirator is faulty
The trigger level setting is too
low.
The patient's voluntary
inspiration is weak.
The time setting is improper.
The respirator is faulty
HFOV Guideline Revised Sept 16 review Sept 21
Remedy
Check for holes in the circuit. Also,
check that the circuit connections are
properly made.
Correct any bend or twist in the
respiration circuit. Remove water from
the circuit. If necessary, replace the
circuit.
With the IMV operating control section,
raise the flow rate setting.
Confirm the supply gas pressure and
check for leaks.
Call an emergency contact number.
Adjust the trigger level setting.
Take appropriate remedial action in
compliance with the doctor's
instructions.
Replace the patient circuit.
Call an emergency contact number.
Adjust the trigger level setting.
Take appropriate remedial action in
compliance with the doctor's
instructions.
Adjust the inspiratory time and breath
rate settings in compliance with the
usage instructions for the IMV operating
control section.
Call an emergency contact number.
Page 28 of 36
Alarm Messages
When an alarm condition arises, the LCD will display an alarm message. When the alarm
condition is cleared; the alarm message will change to a string of black non-bolded
characters. Even when the alarm condition is cleared, the alarm message remains as a
past event record until the [Mute] button is held down for a period of longer than 3 seconds
Alarm message and Meaning of alarm message
Inspiratory pressure upper limit
 This message indicates that the inspiratory pressure is higher than the setting by at
least 0.1 cm H20. The respirator immediately switches to the expiration phase. A lowpriority alarm is issued when the pressure setting is exceeded by one respiration.
However, a high-priority alarm is issued if the pressure setting is exceeded by two
successive respirations.
 It is conceivable that the patient circuit may be collapsed or clogged. It is also
conceivable that excessive water may be caught in a place other than the patient
circuit water trap.
Inspiratory pressure lower limit
 A high-priority alarm is immediately issued if the inspiratory pressure for mechanically
triggered inspiration is lower than its setting.
 It is conceivable that this alarm message may be generated due, for instance, to a
leaky patient circuit, loose connections, or disconnected connections.
PEEP pressure low
 A medium-priority alarm is issued if the PEEP pressure prevailing during expiration
remains lower than the setting for one second. A high-priority alarm is issued if the
 PEEP pressure remains lower than the setting for one minute.
 It is conceivable that this alarm message may be generated due, for instance, to a
leaky patient circuit, loose connections, or disconnected connections.
Breath rate upper limit
 A medium-priority alarm is issued if the total breath rate exceeds the setting. If the
total breath rate remains higher than the setting for one minute, a high-priority alarm is
 issued. A judgment is formulated at the end of inspiration by determining the
inspiration start count prevailing during the last one minute. It is conceivable that the
patient may be breathing at frequent intervals. It is also conceivable that the trigger
level may be improperly set for the patient's spontaneous respiration effort.
Minute-volume-of-ventilation lower limit
 A medium-priority alarm is issued if the minute volume of ventilation is smaller than the
setting. If the minute volume of ventilation remains smaller than the setting for one
minute, a high-priority alarm is issued. It is conceivable that the patient's inspiration
 effort may be weak. It is also conceivable that this alarm message may be generated
due, for instance, to a leaky patient circuit, loose connections, or disconnected
connections.
Minute-volume-of-ventilation upper limit
 A medium-priority alarm is issued if the minute volume of ventilation is larger than the
setting. If the minute volume of ventilation remains larger than the setting for one
minute, a high-priority alarm is issued. This alarm function is operative in the PCV
mode only.
 It is conceivable that the patient may be breathing at frequent intervals. It is also
conceivable that the trigger level may be improperly set for the patient's spontaneous
 respiration effort.
Spontaneous ventilation volume decreased
 A medium-priority alarm is issued if the tidal volume for spontaneous respiration or
supported respiration is smaller than the setting in the VCV or PCV mode. If this state
 persists for one minute, a high-priority alarm is issued. The alarm condition can be
 cleared by holding down the [Mute] button for a period of longer than 3 seconds.
HFOV Guideline Revised Sept 16 review Sept 21
Page 29 of 36

It is conceivable that the patient's spontaneous respiration effort may be weak. It is
also conceivable that the trigger level may be improperly set for the patient's
spontaneous respiration effort.
Mandatory tidal volume decreased
 A medium-priority alarm is issued if the mandatory tidal volume is smaller than the
setting in the VCV or PCV mode. If this state persists for one minute, a high-priority
alarm is issued. It is conceivable that this alarm message may be generated due, for
instance, to a leaky patient circuit, loose connections, or disconnected connections.
Apnea monitoring time
 If no inspiration occurs within the pre-selected time, a medium-priority alarm is issued
so that the respirator enters the apnea backup mode. If this state persists for one
minute, a high-priority alarm is issued. The respirator switches from the apnea backup
mode to the normal ventilation mode when the alarm is reset or when the patient
trigger is activated twice before the next mandatory ventilation.
 It is conceivable that this alarm message may be generated due to weak spontaneous
respiration of the patient or the absence of breathing. It is also conceivable that the
trigger level may be improperly set for the patient's spontaneous respiration effort.
Circuit clogged - Safety valve open
 If the patient circuit is found to be clogged, a high-priority alarm is issued. The
ventilation operation then comes to a stop with the safety valve and expiration valve
opened. When the [Mute] button is held down for a period of longer than 3 seconds
with the patient circuit unclogged, inspected, and connected, the ventilation operation
resumes.
 Locate a clog in the patient circuit and restore it to normal. If the patient circuit cannot
be unclogged, replace it.
Spontaneous inspiration time upper limit
 A medium-priority alarm is issued if the inspiratory time for spontaneous respiration or
supported respiration exceeds 3.5 seconds in the adult mode or 2.5 seconds in the
child mode. If this state persists for one minute, a high-priority alarm is issued.
 The lung compliance may be high. The patient's inspiration effort may be intensified.
There may be a leak in the patient circuit.
MAP abnormal/circuit open
 This alarm message appears if the detected MAP remains below 2 cmH2O for 1
second. This stops HFO vibration, stops MAP control, keeps the expiration valve open to
a certain degree, and provides an inspiration flow rate of 20 Lpm. It is conceivable that
the patient circuit or lip pressure monitor line may be disconnected.
MAP upper limit 1
 This alarm message appears if the automatic alarm setting is exceeded for a period of
longer than 1 second.
 Although an alarm sound is generated with the alarm message displayed, the
respirator does not change its operation. It is conceivable that the alarm message may
be generated due to a clogged circuit or kinked monitor line. Check whether the patient
circuit is twisted, collapsed, or clogged.
MAP upper limit 2
 This alarm message appears 200 msec after the alarm setting is reached. This causes
the HFO vibration to stop, the inspiration valve to fully open, the expiration valve to
fully open, and the safety valve to open. The alarm condition is cleared if the MAP
remains below 3 cmH2O for a period of longer than 1 second. It is conceivable that the
alarm message may be generated due to a clogged circuit or kinked monitor line.
Check whether the patient circuit is twisted, collapsed, or clogged.
MAP lower limit
 This alarm message appears immediately after the MAP falls below the automatic
alarm setting. Although an alarm sound is generated with the alarm message displayed,
the respirator does not change its operation. The alarm condition is cleared when the
MAP is back within the alarm setting range.
 It is conceivable-that the circuit or lip pressure monitor tube may be disconnected.
HFOV Guideline Revised Sept 16 review Sept 21
Page 30 of 36
Check whether the patient circuit is properly connected.
Amplitude upper limit
 This alarm message appears immediately after the amplitude rises above the automatic
alarm setting. Although an alarm sound is generated with the alarm message displayed,
the respirator does not change its operation. The alarm condition is cleared when the
amplitude is back within the alarm setting range. It is conceivable that the patient circuit
and patient volume may have changed.
Amplitude lower limit
 This alarm message appears immediately after the amplitude falls below the automatic
alarm setting. Although an alarm sound is generated with the alarm message displayed,
the respirator does not change its operation. The alarm condition is cleared when the
amplitude is back within the alarm setting range. It is conceivable that the patient
circuit and patient volume may have changed.
Both gases stopped - Safety valve open
 A high-priority alarm is issued when the air and oxygen are both in short supply. The
ventilation operation then comes to a stop with the safety valve opened. The air and
oxygen supplies are shut off.
Oxygen pressure low
 A high-priority alarm is issued if the oxygen supply pressure falls below 2.4(0.4 kg/cm2
while the operation is performed at a supply oxygen concentration of 22% or higher.
The operation is then performed with the percentage of air raised to 100%. It is
conceivable that the piped oxygen supply pressure may be abnormal.
Air pressure low
 A high-priority alarm is issued if the piped air supply pressure falls below 2.4(0.4
kg/cm2. It is conceivable that the piped air supply pressure may be abnormal.
No air source - Oxygen operation
 A high-priority alarm is issued if the wall air pressure falls below 2.4(0.4 kg/cm2. In
this instance, the operation cannot be continued.
 It is conceivable that the air supply pressure may be abnormal.
Expiration valve open
 This alarm message appears if the expiration flow rate is higher than 3 LPM when a
period of 150 msec elapses after the start of inspiration and the resulting cumulative
value is 60 mL. Contact your local dealer.
Air valve open
 This alarm message appears if the air inspiration flow rate is higher than 5 LPM when a
period of 60 msec elapses after the start of expiration. This alarm function is
operative only when the pressure trigger is selected. Contact your local dealer.
Oxygen valve open
 This alarm message appears if the oxygen inspiration flow rate is higher than 5 LPM
when a period of 60 msec elapses after the start of expiration. This alarm function is
operative only when the pressure trigger is selected. Contact your local dealer.
Expiration valve problem
 This alarm message appears if the inspiration flow rate is higher than 3 LPM when a
period of 150 msec elapses after the start of inspiration and the resulting cumulative
value is 60 mL. Contact your local dealer. Expiration valve clogged
 It is conceivable that the expiration valve may be in trouble.
Air valve clogged
 This alarm message appears if the air flow rate remains below 3.33 LPM for 100 msec
although the air valve open signal value is greater than 450 during inspiration. Contact
your local dealer.
Oxygen valve clogged
 This alarm message appears if the oxygen flow rate remains below 3.33 LPM for 100
msec although the oxygen valve open signal value is greater than 450 during
inspiration. Contact your local dealer.
ADC wrap sensor faulty
 It is conceivable that the sensor unit may be in trouble. Contact your local dealer.
HFOV Guideline Revised Sept 16 review Sept 21
Page 31 of 36
Internal oxygen sensor faulty
 It is conceivable that the internal oxygen sensor may be in trouble. Contact your local
dealer.
Internal temperature sensor faulty
 It is conceivable that the internal temperature sensor may be in trouble. Contact your
local dealer.
Internal voltage sensor faulty
 It is conceivable that the sensor unit or respirator power supply may be in trouble.
Contact your local dealer.
Internal oxygen concentration high
 It is conceivable that there may be an oxygen leak in the respirator. Contact your local
dealer.
Internal temperature high
 It is conceivable that the temperature in the respirator may be too high.
 Ensure that the operating environmental temperature is not higher than 40(C. Contact
your local dealer.
Default settings used
 This message appears to indicate that the factory default settings are used for
operation.
Default compliance used
 This message appears to indicate that the factory default compliance setting (3.45
mL/H2O) is used for operation.
Default altitude used
 This message appears to indicate that the factory default altitude setting (0 m above
sea level) is used for operation.
HFOV Guideline Revised Sept 16 review Sept 21
Page 32 of 36
Appendix Three - Sample HFOV audit form
Data Collection sheet for HFO
Date admitted to ICU:
Please affix patient label
Date of invasive ventilation: Primary diagnosis:
Patient Name:
Date of birth:
NHS / K Number:
Prior to starting HFOV:
Indication for starting HFOV:
Name:
………………….. Date of birth: …………………..
Hospital no.
…………………..
Date
pH
SpO2
FiO2
P insp.
Mean arterial pressure
HR
Sex – M/F
Time
Blood gas
PaO2settings
PaCO2
Ventilator
PEEPsettings
Freq
Base excess
I:E Ratio
Tidal volume
Cardiovascular
status
Inotropes – None/ Adrenaline/ Nor adrenaline/ Dobutamine/ Vasopressin
Adjuncts – None/ Frusemide/ Nebulised Prostacyclin/ Proning/ β2 agonists/ Muscle relaxants
CVVH – Yes/ No
After initiation of HFOV:
Blood gases and cardiovascular status during first 24 hours:
After
pH
PaO2
PaCO2
SpO2
Mean Art
Pressure
HR
Fluid
boluses
Comment
1 hour
6 hours
24 hours
Over entire 24 hours
Inotropes – None/ Adrenaline/ Nor adrenaline/ Dobutamine/
Vasopressin
HFOV Guideline Revised Sept 16 review Sept 21
Page 33 of 36
HFOV settings during first 24 hours:
After
1 hour
FiO2
MAP
Amp / Cycle vol.
Insp%
Freq
Bias / base flow
6 hours
24 hours
Over entire 24 hours Adjuncts – None/ Frusemide/ Nebulised Prostacyclin/ Proning/ β2
agonists/
Muscle relaxants
Weaning from HFOV:
Date and time when switched to conventional ventilator:
Reason:
Blood gases, and HFOV and Conventional ventilator settings at point of change:
pH
PaO2 PaCO2
FiO2 MAP
FiO2
Freq
P insp.
Blood gases and cardiovascular status
Mean Art Pressure HR Fluid boluses
SpO2
Insp%
PEEP
HFOV
settings
Amp / Cycle vol.
Comment
Bias / base flow
Conventional ventilator
settings I:E Ratio
Freq
Tidal volume
Other details Inotropes – None/ Adrenaline/ Nor adrenaline/ Dobutamine/ Vasopressin
Adjuncts – None/ Frusemide/ Nebulised Prostacyclin/ Proning/ β2 agonists/
Muscle relaxants
Overall outcome:
Date weaned from mechanical ventilator:
Date of ICU discharge/death (please circle):
Date of hospital discharge/death (please
circle):
HFOV Guideline Revised Sept 16 review Sept 21
Page 34 of 36
Appendix Four
Competency document Managing Care of the High Frequency Oscillation Ventilation (HFOV) Patient
Competency
The Practitioner is able to:-
Factors to Consider Evidence
of
learning
Required
1. Perform an assessment of the
Oscillated patient
Identify causes of
respiratory failure
2. Understand the principles of Oscillation High frequency, low
volumes
3. Examine the indications for Oscillation CO2 levels
for a patient with respiratory failure
Peak Pressures
O2 requirements
4. Demonstrate an awareness of
Hz, Mean Pressure,
Oscillation settings and ranges on The
Cycle Volume
Vision Alpha
5. Recognise situations in which patients Monitor ABG’S
are not receiving optimal ventilation. And Hz, Mean Pressure,
act accordingly.
Cycle Volume
Emergency Care
required Patient
Complications
6. Identify when a patient requires
ABG’s improved over
weaning from Oscillation
sufficient length of
time
7. Demonstrate knowledge of how to
change ventilation modes
CPAP or Vent modes
8. Demonstrate ability to Troubleshoot
alarms
Alarms
9. Discuss the nursing actions taken in
emergency situations associated
with oscillation
Emergency
equipment
10. Demonstrate correct use of
humidification system
Alarms, Settings
available, fluid
required
Evidence of Learning
O – Observation
WP – Work Product
PA – Project or Assignment
CE – Candidate Explanation
HFOV Guideline Revised Sept 16 review Sept 21
Page 35 of 36
Initial Final
Rating Rating
Appendix Five
Equality Impact Assessment Report
1.
Name of Policy or Service
Response to external best practice policy
2.
Responsible Manager
Owen Bennett (Clinical Quality, Risk and Safety Manager)
3.
Name of person Completing EIA
Mary Beckenham Critical Care Clinical governance Lead
4.
Date EIA Completed
1/5/2010, reviewed 1/10/2013, 4/10/2016
5.
Description and Aims of Policy/Service
This clinical guideline has been written to inform adult critical care staff of how
to safely manage critically ill patients requiring high- frequency oscillatory
ventilation.
6.
Brief Summary of Research and Relevant Data
There is no research or relevant data at the present time.
7.
Methods and Outcome of Consultation
Consultations have been carried out with the following:
Adult critical care consultants and senior nurses
Comments from the above consultations have been received and
incorporated where appropriate.
8.
Results of Initial Screening or Full Equality Impact Assessment:
Equality Group
Assessment of Impact
Age
Gender
Race
Sexual Orientation
Religion or belief
Disability
No Impact Identified
No Impact Identified
No Impact Identified
No Impact Identified
No Impact Identified
No Impact Identified
Dignity and Human Rights
Working Patterns
Social Deprivation
No Impact Identified
No Impact Identified
No Impact Identified
9.
Decisions and/or Recommendations (including supporting rationale)
From the information contained in the procedure, and following the initial
screening, it is my decision that a full assessment is not required at the
present time.
10.
11.
Equality Action Plan (if required) N/A
Monitoring and Review Arrangements
For review 27/09/2019
HFOV Guideline Revised Sept 16 review Sept 21
Page 36 of 36