High Frequency Ventilation

Question 1

High Frequency Ventilation

Answer 1

-Positive pressure ventilation with rates in excess of 150 bpm and tidal volumes of approximately the anatomical dead space

Question 2

High Frequency Ventilation

characteristics

Answer 2

-Rate expressed in Hertz (HZ)

	-1 HZ= 60 bpm

-Amplitude (POwer, delta P) refers to the difference between Peak inspiratory pressure (PIP) and PEEP (Basically gives you the VT)

-all forms of HFV have common characteristics

	-RR> 150 bpm

	-VT= 1-3ml/kg

	-Noncompliant vent circuits

Question 3

-Forms of high frequency ventilation

Answer 3

-Types of HFV High frequency ventilation/ Acronym HFPPV. Expiation method Passive

	-High frequency jet ventilation / HFJV/Passive

	-High Frequency flow interrupter ventilation/ HIFFIV/ Passive

	-High frequency oscillator Ventilator/ HFOV/ Active

Question 4

High Frequency Ventilation

-Indications

-Early rescue

Answer 4

-Very low birth weight (VLBW) infants with RDS

		-Air leak Syndrome (PIE< pnemo, tracheoesophageal fistula or bronchopulmonary fistula)

Question 5

High Frequency Ventilation

-Indications

-Failure of conventional ventilation

Answer 5

-ARDS

		-Congenital diaphragmatic hypertension

		-Persistant pulmonary hypertension

		-Pnemonia

		-Pulmonary hemorrhage

		-Meconium aspiration syndrome

Question 6

Major advantage of HFV

Answer 6

-Reduces risk of ventilator induced lung injury when conventional vent settings are high

-Major advantage of HFV that provides adequate oxygenation and ventilation at

	-Lower PIUP and mean pressure than conventional modes of ventilation decrease barotrauma

	-Lower volumes than conventional modes of ventilation decreases volutrauma (deliveries Vt in small package)

Question 7

High Frequency Oscillator Ventilation

-Principles

Answer 7

-Most widely used high frequency HFOV

	-Active expiration piston driven for both inhalation and exhalation		

	-Uses conventional ETT

	-Alveoli stay open at all time

Question 8

High Frequency Oscillator Ventilation

-Intail settings for oscillation

Answer 8

-Usually 8-10 (480-600) (higher for smaller pt= 10-15 hz)

	-Alplitude (power) = adjust to chest wiggle… visual chest wiggle

	-I-time is usually set at 33%

	-MAP (Oscillator) = Direct = 8-10 or 2-4 above map on conventional mech ventilation

	-Flow 8-15 lpm= preterm, 10-12 lpm= term

Question 9

High Frequency Oscillator Ventilation

-Adjustment of controls

Answer 9

-To adjust for CO2

-Adjust amplitude

-Adjust HRZ (higher frequency= smaller volumes, less CO2 removal, lower frequency= larger volumes displacement and improved CO2 removal)

-Closer HRZ and amplitude- small volume

-To adjust PaO2

-Change FiO2

-MAP

-Center the Piston

Question 10

High Frequency Oscillator Ventilation

fixing oxygenation and ventilation issues

Answer 10

Poor Oxygenation

-Increase FiO2

-Increas MAP

Over Oxygenation

-Decrease FiO2

-Decrease MAP

Underventilation

-Increase Amplitude

-Decrease Frequency

Overventilation

-Decrease Amplitude

-Incread frequency

Question 11

High Frequency Oscillator Ventilation

-Heated humidification

Answer 11

if thick secretions, increase humidifier temp

Question 12

High Frequency Oscillator Ventilation

-Adequate ventilation

Answer 12

-Chest vibration, SPO2, ABG adequate

Question 13

High Frequency Oscillator Ventilation

-Wean

Answer 13

-FiO2 as tolerated to target SpO2/ PaO2

	-Wean MAP in 1-2 cmH2O increments

	-Wean Delta P in 2-4 cmH2) increments

Question 14

High Frequency Oscillator Ventilation

-Extubation

Answer 14

-MAP= 7-9 cmH2O

	-FiO2=< 30-40%

	-Amplitude < 20

	-Infant is noted to breathing comfortably

	-CXR is clear or near clear

Question 15

High Frequency Oscillator Ventilation

-Hazard

Answer 15

-Gas trapping

	-Hyperinflation (CXR, chest expiration/ lung volumes should be between 8-9 ribs)

	-Obstruction of airway with secretions

	-Hypotension

	-Necrotizing tracheobronchochtis

	-Difficult to assess ventilation via chest wall movement as the chest vibrates instead of raising and falling (wiggles) unable to assess breath sounds as well

Question 16

High Frequency Oscillator Ventilation

-Key Points (Suctioning)

Answer 16

-No suctioning during HFVO during the first 24 hours unless clinically necessary

	-In line suctioning only

	-Press stop button while quickie suctioning

	-Only alarm we set is min/max PAW alarm = usually above 2 and below 2

Question 17

High Frequency Jet Ventilation

Answer 17

-Uses a special ET tube or jet port adapter in conjunction with conventional ventilation (for PEEP and sigh breaths)

-Has Passive Exhalation

-Tiny jet pulses of fresh gas generate the VT