The document discusses High Frequency Oscillatory Ventilation (HFOV), including its uses in neonatal and adult patients, how it works, and how to operate it. HFOV aims to support lung oxygenation and CO2 removal while reducing ventilator-induced lung injury. It works by using very small, high frequency breaths to gently inflate the lungs rather than large tidal volumes. The settings control pressure and flow to optimize gas exchange while protecting the lung tissue.

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 2 x Paw PaO 2 Predictor of mortality High value = bad outcome

5. MV won’t cure cancer HFOV won’t help with: COPD IPF Asthma Sarcoidosis HFOV Adult Patient Selection

6. HFOV - Why

7. HFOV Objectives Support Lung Oxygenation CO 2 Removal 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)

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 2 Removal Hertz Amplitude (  P)

19. Primary control of CO 2 is by the stroke volume produced by the Power Setting

20. CO 2 Removal

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

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 2 for Sat’s > 90% When FiO 2 60%, 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 2 <100 with pH 7.25

36. “ On Patient” Issues Inability to increase Paw Fluctuating Paw Changes in settings Inappropriate patient response

37. Inappropriate Patient Response Need for ETT suctioning Low lung volume Overdistended lung Marginal cardiovascular status

38. Tricks Prone positioning ETT Leak Bronchoscopy

39. HFOV Case Study Putting it all together

41. Day 16 CMV Pressure limited A/C FiO 2 70% Vt 296 VE 9.2 RR 32 PEEP 12 Paw 24 PIP 36 I:E 1:1 Arterial blood gases pH 7.09 PaCO 2 200 HCO 3 49 PaO 2 80 BE 26 SaO 2 91 A-a gradient 169.1 OI 21

42. “ Oh yeah, did I mention…?” 23 y/o female ARDS 3 CT Prone iNO ECMO candidate

43. HFOV: Indications Indication: OI > 15 FiO 2 > 60% PEEP > 10 PIP > 35 Paw > 15 Respiratory acidosis Inadequate alveolar ventilation Pt. Values: OI 21 FiO 2 70% PEEP 12 PIP 36 Paw 24 pH 7.09 PaCO 2 200

44. HFOV: Initiation Initial HFOV settings FiO 2 100% Paw 30 Amplitude 62 Hz 5.0 It% 33% Bias flow 30 Arterial blood gases pH 7.26 *7.09 PaCO 2 114 *200 PaO 2 184 *80 HCO 3 52 BE 22 SaO 2 95.2 *ABG prior to HFOV

45. Management: Strategy HFOV settings FiO 2 80% Paw 30 Amplitude 62 Hz 4.0 It% 50% Bias flow 30 Arterial blood gases pH 7.35 * 7.26 PaCO 2 88 * 114 PaO 2 104 * 88 HCO 3 49 BE 22 SaO 2 96 * ABG prior to changes in parameters

46. Management: 24 hours HFOV settings FiO 2 60% Paw 26 Amplitude 62 Hz 4.0 It% 50% Bias flow 30 Arterial blood gases pH 7.44 PaCO 2 74 PaO 2 97 HCO 3 50 BE 24 SaO 2 95

47. HFOV Day 7 HFOV settings FiO 2 50% Paw 16 Amplitude 50 Hz 5.0 It% 40% Bias flow 40 Arterial blood gases pH 7.41 PaCO 2 66 PaO 2 83 HCO 3 43 BE 16 SaO 2 95

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