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High Frequency Oscillatory Ventilation (HFOV) (2.03)

High Frequency Oscillatory Ventilation (HFOV) (2.03) - Policies, Clinical, UWHC Clinical, Department Specific, Respiratory Care Services, Mechanical Ventilation


2.03 High Frequency Oscillatory Ventilation
Category: UWHC Departmental Policy
Effective Date: November 1, 2015
Version: Revision
Manual: Respiratory Care Services
Section: Mechanical Ventilation

I. Purpose

High Frequency Oscillatory Ventilation (HFOV) is used for the treatment of various forms of
respiratory failure and those failing mechanical ventilation. Lung protection is achieved by inflating the lung
with a continuous distending pressure and superimposing very small volume swings.

Management of the patient is an art.
To manipulate oxygenation, adjustments made in the patient’s lung volume via mean airway pressure
(Pāw) will have a profound effect. There is a near linear relationship between lung volume and surface
area for gas exchange.
Ventilation is primarily manipulated by amplitude (∆P) or power control which impacts the patient’s
tidal volume. Further manipulation for ventilation can be done by making adjustments to the frequency
(Hz) or % I-Time. Counter-intuitively, lowering the frequency will increase delivered tidal volume and
thus lower PaCO2. Increasing the % inspiratory time maximizes the delivered tidal volume as well.

II. Equipment

A. 3100 A-patients under 35kg
B. 3100 B-patients over 35kg
C. UPS battery pack
D. Pressure bag for water
E. External oxygen analyzer with alarms
F. Closed suction set up for ETT 7.0 or greater use specific adapter. See related link
G. NICU will place white or blue swivel elbow onto the oscillator circuit.

III. Policy

A. Machine and circuit calibration will be completed in C5/115 prior to patient use.
B. Oscillator will be connected to UPS.
C. Inline suctioning daily (preferable on the day shift) and when indicated: decrease chest wiggle,
increase in pCO2 or decrease inSpO2.
D. The piston will be stopped for 10-15 seconds during suctioning followed by a recruitment
E. Patients shall be assessed by a Respiratory Therapist at a minimum of every four hours.
F. If patients are receiving conventional ventilation prior to the initiation of HFOV, the
conventional ventilator should remain on stand-by at the bedside. The ventilator circuit will
expire after 24 hours of non-use.
G. No Helium therapy, or MDI can be used in line with the oscillator.
H. Nitric Oxide can be used in line with the oscillator.
I. Aerosolized, medication including nitric oxide, can be given with the nebulizer placed closest to
the patient. See related link.

J. In the NICU the ET tube adapter will be placed on the circuit prior to starting up the oscillator.
*If the ET tube adapter is added after the patient is placed on the oscillator, compensate if
necessary for the added dead space by adjusting the Delta P.
K. Patient transport on the oscillator is not recommended due to poor electrical compliance.

IV. Procedure

A. Connect the oscillator to the UPS.
B. Add the external oxygen analyzer.
C. With green plug sealing circuit, set oscillator settings based on provider’s order or guideline.
See related link.
D. Connect the patient’s ETT to the oscillator circuit. Press and hold the reset button until
oscillation begins.
E. Assess patient’s chest wiggle and adjust ∆P to desired wiggle.
1. Less than10 kg = chest wiggle to umbilicus
2. Less than 35 kg = chest wiggle to groin
3. Greater than 35 kg = check wiggle to mid thigh
F. Fine tune all settings once the oscillator is on the patient. Small adjustments made one at a time
may have a large impact in patient response.
G. Suctioning daily and as needed with any acute rise in pCO2, decrease in chest wiggle or
1. Stop the piston when the suction catheter is inserted into the ETT, as active exhalation is
blocked. Distal air-trapping can occur as well as collapse of small airways.
2. If the patient desaturates with suction, perform a recruitment maneuver. Perform recruitment
maneuver after every suction. Discuss with the provider the amount of Pāw increase (normal
is between 2-10 cmH20 based on patient size) as well as the duration (normal is 20-40
seconds based on patient size). With the piston stopped, increase the Pāw and duration
(inspiratory hold) as ordered by provider.
3. Restart the piston by pressing and holding the reset button. There will be a delay before
the machine cycles.
4. Repeat recruitment maneuver until SpO2 returns to baseline.
5. Use open suction if secretions aren’t clearing.
H. Weaning the oscillator.
1. Decrease the FiO
to 60% before lowering Pāw.
2. Decrease the Pāw keeping oxygen saturations = 88%.
a. Pediatric: Decrease Pāw by 1-2cm H2O over several hours until Pāw <20 cmH2O.
b. Adult: Decrease Pāw by 5cm H2O-adult over several hours until Pāw <24 cmH2O.
3. Wean Delta P to less than 30 cmH
4. Consider conventional ventilation.

V. References

A. www.viasyshealthcare.com
B. AARC Clinical Practice guideline “Patient-Ventilator system checks”.
C. Technical Support Service 1-800-520-4368 and follow prompts to Respiratory Manual.

Approved by Director and Medical Director of Respiratory Care:
A copy of this Policy & Procedure is available in the Respiratory Care Office [E5/489].