1. High Frequency Oscillatory Ventilation

• Who

Why

When

Where

What

How

? 2. Neonatal Uses of HFOV

Hyaline membrane disease

Persistent pulmonary hypertension

Pulmonary interstitial emphysema

(prevention and treatment)

Sepsis / Pneumonia

Congenital diaphragmatic hernia

Meconium aspiration syndrome

3. HFOV Adult Indications

ARDS

• PCIRV

• Paralysis

• High FiO 2

Air Leak Syndrome

ECMO Candidates

4. Oxygenation Index

OI =FiO 2x Paw

PaO 2

Predictor of mortality

High value = bad outcome

5.

MV wont cure cancer

HFOV wont help with:

COPD

IPF

Asthma

Sarcoidosis

HFOV Adult Patient Selection 6. HFOV - Why 7. HFOV Objectives

Support Lung

• Oxygenation

• CO 2Removal

Reduce Vent Induced Lung Injury

8. Carney, CCM 2005 9. CMV vs HFOV 10. HFOV- When

Timing is everything

ASAP

1-5 days of CMV

Not as a last resort

11. 53% 67% 31%37% 31% 30% 30 day mortality 5.1 5.7 7.2 2.7 4 # of days CV pre HFOV 49 33 28 24 12 29 OI 23 22 27 22 25 APACHE II 17 24 16 75 432 70 n Fort (1997) Mehta (2001) Anderson (2002) MOAT II (2002) ARDS Net (2000) Duke (2005) 12. 13. HFOV - Where?

ICU

Transport Limitation

14. HFOV - What? 15. HFOV

Where is the PEEP, tidal volume, graphics, and respiratory rate on this machine!?.

Anonymous Surgeon

16. HFOV Design

Magnet

Bias Flow

CPAP with a wiggle

Expiratory Resistance

ACTIVE EXHALATION

17. Ventilator Settings

Hertz = BPM

Power (Amplitude P)

Paw

FiO 2

Bias Flow

Inspiratory time %

18. CO 2Removal

Hertz

Amplitude ( P)

19. Primary control of CO 2is by the stroke volume produced by the Power Setting 20. CO 2Removal 21. . 22. HFOV Settings: Inspiratory Time %

33%= 1:2 I:E Ratio

• Default

50%= 1:1 I:E Ratio

• Caution

23. Oxygenation

Paw

FiO 2

What was that Oxygenation Index thing?

24. Oxygenation

The Paw is used to inflate the lung

Paw = Lung Volume

Paw =PaO 2

(usually)

Use blender to adjust FiO 2

25. HFOV Controls PaO 2 PaCO 2 26. Bias Flow CDP Control Balloon x 27. Pressure to Lung 28. HFOV Pressure Attenuation 29. 30. Mechanisms of Gas Exchange 31. HFOV - How Initial Settings

FiO 2=1.0

Hz= 5.0

Power setting =5

Paw =CMV + 5

Insp Time = 33%

Flow = 30

32. Clinical Observations

Chest Wiggle Factor

CXR T8-9

Pulse oximetery

TCO 2

ABG

33. Weaning

Wean FiO 2for Sats > 90%

When FiO 260%, wean Paw by 1

Return to CMV when:

• FiO 2< 40%

• Paw 15-20

• Amplitude < 40

34. HFOV: Conversion

• Pressure limited ventilation

• Delivered tidal volume ~6 ml/kg

• PEEP ~10 cm H 2 O

• Adjust for Paw same as HFOV

• FiO 2~40 - 50%

35. Signs of Failure

OI > 42 at 48 hrs HFOV

Unable to wean FiO 2> 10% within 24 hours

Unable to PaCO 215

FiO 2> 60%

PEEP>10

PIP >35

Paw>15

Respiratory acidosis

Inadequate alveolar ventilation

Pt. Values:

OI 21

FiO 270%

PEEP12

PIP 36

Paw24

pH7.09

PaCO 2 200

44. HFOV: Initiation

• Initial HFOV settings

• FiO 2 100%

• Paw 30

• Amplitude62

• Hz5.0

• It% 33%

• Bias flow30

Arterial blood gases

• pH7.26*7.09

• PaCO 2 114*200

• PaO 2184*80

• HCO 352

• BE22

• SaO 2 95.2

*ABG prior to HFOV

45. Management: Strategy

• HFOV settings

• FiO 2 80%

• Paw 30

• Amplitude62

• Hz 4.0

• It% 50%

• Bias flow30

Arterial blood gases

• pH7.35* 7.26

• PaCO 2 88* 114

• PaO 2104* 88

• HCO 349

• BE22

• SaO 2 96

* ABG prior to changes in parameters

46. Management: 24 hours

• HFOV settings

• FiO 2 60%

• Paw 26

• Amplitude62

• Hz 4.0

• It% 50%

• Bias flow30

Arterial blood gases

• pH7.44

• PaCO 2 74

• PaO 297

• HCO 350

• BE24

• SaO 2 95

47. HFOV Day 7

• HFOV settings

• FiO 2 50%

• Paw 16

• Amplitude50

• Hz 5.0

• It% 40%

• Bias flow40

Arterial blood gases

• pH7.41

• PaCO 2 66

• PaO 283

• HCO 343

• BE16

• SaO 2 95

48. 49. Why did HFOV succeed?

Low pressure swings allowed air leaks to seal

Paw recruited collapsed lung

50. Derdak AJRCCM 2002 51. HFOV Summary

CPAP

Small pressure swings

Lung protection

Lung support

Ultimate low Vt strategy

Start early

Be aggressive