3100B Ventilator

1
3100B Ventilator
2
3100B Ventilator

• Approved for sale outside the
• US in 1998 for patients
• weighing gt 35 kg failing CMV
• Approved September 24, 2001
• by the FDA for sale in the US

3
Pulmonary Injury Sequence

• There are two injury zones during mechanical
  ventilation
• Low Lung Volume Ventilation tears adhesive
  surfaces
• High Lung Volume Ventilation over-distends,
  resulting in Volutrauma
• The difficulty is finding the Safe Window

Froese AB, Crit Care Med 1997 25906
4
High Frequency Ventilation

• Advantages-
• Enables ventilation above the closing volume
  with lower alveolar pressure swings.
• Safe way of using Super PEEP.

5
Theory of Operation

• Controls for Oxygenation and Ventilation are
  mutually exclusive.
• Oxygenation is primarily controlled by the Mean
  Airway
  Pressure (Paw) and the FiO2.
• Ventilation is primarily determined by the stroke
  volume (Delta-P) and
  the frequency of the ventilator.

6
Large Patient Strategies

• When to consider HFOV use?
• As with all candidates, the earlier the better
• FiO2 gt60, PEEPgt10 with PaO2/FiO2 ratiolt200
• Relative contra-indications
• Obstructive lung disease
• Elevated ICP

7
Acute Respiratory Distress Syndrome
8
19 yo female - Pneumococcal pneumonia (Day 1)
FiO2 100, PEEP 20, PIP 60, SpO2 80
9
19 yo female - Pneumococcal pneumonia (Day 2)
FiO2 100 SpO2 - 78
10
19 yo female - Pneumococcal pneumonia (Day 3)
FiO2 100 and SpO2 70
11
What if physiologic goals cant be met using lung
protective strategies?
What if physiologic goals cant be met using lung
protective strategies?
12
Large Patient Strategies

• ARDS
• FiO2 matched
• Paw 5 cmH2O above CMV
• Power of 4.0 and then adjust for good CWF
• Bias flow gt20 lpm, higher if required to maintain
  Paw
• Frequency determined by patient size and
  compliance
• I-Time set to 33

13
Oxygenation Strategies

• ? Paw until you are able to ?FiO2 to 60 with a
  SaO2 of 90
• Avoid hyperinflation
• Optimize preload, myocardial function
• Ventilation Strategies
• CWF- adjust Power Setting to target PaCO2 to
  between 45-55 mmHg
• ? frequency by 1Hz increments if Amplitude is
  maximized
• Induce cuff leak
• allow permissive hypercarbia if indicated,
  keeping pHgt7.25

14
HFOV Strategy

• If CO2 retention persists, decreasing cuff
  pressure to allow gas to escape around the ET
  tube will move the fresh gas supply from the wye
  connector to the tip of the ET tube

15
Clinical Tips

• Failure Criteria
• Inability to decrease FiO2 by 10 within the
  first 24 hrs.
• Inability to improve ventilation or maintain
  ventilation (after optimizing both frequency and
  amplitude) with PaCO2 lt 80 with pH gt 7.25.
• A transcutaneous monitor is useful for trending
  CO2.

16
Clinical Assessment

• Suctioning
• Indicated by decreased or absence CWF, decrease
  in O2 saturation, or an increase in TcCO2.
• Remember that each time the patient is
  disconnected from HFOV, they will potentially
  de-recruit lung volume.
• Closed suction catheters may mitigate
• de-recruitment
• It may be necessary to temporarily ? Paw or
  perform recruitment maneuver

17
Derecruitment during Disconnect

• Minimize suction
• attempts
• Use closed suction systems
• Avoid unnecessary disconnects
• May require RM or ?FiO2 to return SaO2 to
  baseline

18
Clinical Assessment

• Chest Wiggle factor (CWF) must be evaluated upon
  initiation and followed closely after that.
• CWF absent or becomes diminished is a clinical
  sign that the airway or ET tube is obstructed.
• CWF present on one side only is an indication
  that the ET tube has slipped down a primary
  bronchus or a pneumothorax has occurred. Check
  the position of the ET tube or obtain a CXR.
• Reassess CWF following any position change.

19
Clinical Assessment

• Chest X-rays
• Obtain the first x-ray at the (4) hour mark to
  determine the lung volume at that time. Paw may
  need to be re-adjusted accordingly.
• Always obtain a CXR , if unsure as to whether the
  patient is hyper-inflated or has de-recruited the
  lung.

20
Clinical Assessment

• Auscultation
• Breath sounds-listen to the intensity or sound
  that the piston makes, it should be equal
  throughout.
• Heart Sounds - stop the piston, (the patient is
  now on CPAP) listen to the heart sounds quickly,
  and restart the piston.

21
Clinical Tips

• Weaning -
• Wean FiO2 for arterial saturation gt 90
• Once FiO2 is 60 or less, re-check chest x-ray
  and if appropriate inflation, begin decreasing
  the Paw in 1cmH2O increments
• Wean Delta-P in 5 cmH2O increments for PaCO2
• Once the optimal frequency is found, leave it
  alone

22
Aerosol Therapy

• Patients who are actively wheezing or have RAD
• administration via bagging- try to coordinate
  with suctioning
• IV terbutaline for patients who do not tolerate
  disconnects
• promising new nebulizer technology

23
Practical Considerations

• Humidification of bias flow accomplished with a
  traditional heated humidifier
• Longer, flexible circuit allows patient
  positioning to prevent skin breakdown
• Infection control issues

24
Managing Large Patients

• Most patients will require heavy sedation and
  occasional neuromuscular blockers to be
  maintained on the 3100B.

25
HFOV Management

• Guidelines for Transition to CMV
• Paw lt 24 cmH2O or stalled
• FiO2 lt 50 or stalled
• gt 4 days HFOV
• Return to CMV at similar Paw

26
3100B Rescue Trial

• Fort P, et al. High-frequency oscillatory
  ventilation for adult respiratory distress
  syndrome-a pilot study. Crit
  Care Med 1997 25937-947
• Seventeen patients failing inverse ratio
  ventilation recruited for
  rescue with HFOV (3100B)
• Predicted mortality gt 80 percent

27
3100B Rescue Trial
Fort P, Crit Care Med 1997 25937
28
3100B Rescue Trial
Fort P, Crit Care Med 1997 25937
29
Multicenter Oscillator ARDS Trial

• Prospective Randomized Controlled Trial of the
  SensorMedics 3100B HFOV for adults
  with ARDS
• Follow-up to MOAT Pilot Rescue Trial
• Early Entry, Non-Crossover Trial
• Ten Institutions, North American Study
• 
  Derdak, AJRCCM
  2002

30
Patient Demographics - Baseline
HFOV CV N 75 73 Age 48 (17) 51 (18) Kg 78 (25)
81 (26) Apache II 22 (6) 22 (9) Sepsis 47 47 Pn
eumonia 19 16 Trauma 21 18 Immune
Compromised 12
14 Airleak 16 19
NS
31
Ventilator Strategies - Goals

• Normalize lung volume
• Minimize peak ventilator pressures
• Physiological targets included
• Oxygen Saturation gt 88
• Delay weaning mPaw until FiO2 lt 50
• pH gt 7.15
• PaCO2 in the range of 40 70 mmHg

32
Primary Outcome Status at 30d
HFOV CMV N 75 73 Died 37 52 Alive
RS 41 22 Alive - no RS
21 26 P0.098 HFOV 61 on vent vs CMV
73 on vent
33
MOAT2 - Secondary Outcomes
HFOV(n75) CV(n73) ? Blood Pressure 0
3 Airleak 9
12 O2 Failure (OI gt42 after 48h) 5
8 pH lt 7.15 5
8 Mucus Plug 5 4 NS
34
MOAT2 Conclusions

• Based on a study of 148 patients, use of HFOV
  for the
  treatment of severe ARDS resulted in an
  absolute reduction in
  mortality by 15.
• This reduction trend in mortality is still
  recognizable at
  six months in this same population.
• There may also be benefits related to chronic
  lung change as reflected
  by the small but extended use
  of respiratory support in the
  conventional ventilation
  managed patients.

35
MOAT - Comparison with ARDSnet
MOAT ARDSnet (6ml/kg) 30d mortality 37 31
P/F 114 138 Paw 22 17 PEEP
13 9 OI 24 12 Sepsis
47 27
ARDS NET, NEJM 2000
36
Changing Medical Practice

• Changing Medical Practice is the Most Difficult
  Task
• 6 ml/kg tidal volume ventilation for ARDS
• Reasons of Non-Compliance
• Reluctance to give up control to a protocol
• Patient comfort
• Acidosis
• Oxygenation
• Therefore
• Most patients with ARDS are not managed with LPV
• HFOV has the potential to remove most barriers
  to use of LPV

Rubenfeld GD et al ATS 2001
37
A Prospective Trial of HFOV in Adults with ARDS

• Patient Population
• 23 Adults 10F, 13M
• Age 48 15 yrs
• Weight 72 17 kg
• Apache II 21 7
• LIS 3.4 0.6
• Diagnosis
• Pneumonia/Sepsis 12
• Burn 5
• Bone Marrow Transplant 4
• Other 2
• 
  
• Mehta et al. CCM 20011360-1369

38
A Prospective Trial of HFOV in Adults with ARDS

• Patient Population
• Prior Vent Days 6.1 5.6 days
• PaO2/FiO2 (mm Hg) 100 41
• OI (FiO2 xPaw x 100/PaO2) 33 20
• Pressures during CMV
• PIP (cmH2O) 37 4
• Paw 24 3
• PEEP 13.8 2.4
• Mehta et al. CCM 20011360-1369

39
A Prospective Trial of HFOV in Adults with ARDS

• Outcomes
• Reason for HFOV withdrawal
• Successfully weaned 10
• Withdrawal of life support/death 11
• Technical problem 2
• ICU Survival 7/23 (30)
• Nonburn patients 7/17 (41)
• Burn patients 0/5
• Mehta et al. CCM 20011360-1369

40
A Prospective Trial of HFOV in Adults with ARDS

• Days of Prior Ventilation
• Non Survivors 7.8 5.8 days
• Survivors 1.6 1.2 days
• Mehta et al. CCM 20011360-1369

41
HFOV in Adults with ARDS

• 42 patients failing CMV
• Baseline P/F ratio 99(46) increased to
  191(121) after 24 hours without HFOV related
  adverse events.
• 30 day mortality was 43
• Subset analysis showed higher 30 day mortality
  in
  patients on CMVgt3 days(67)

M David et al ICM July,2003
42
Rescue Therapy with HFOV Dont wait too late
43
Adjunctive Therapies - iNO

• Post hoc analysis of 108 pediatric patients in a
  RCT with AHRF and iNO
• Comparisons
• HFOV plus iNO (n14)
• HFOV alone (n12)
• CMV plus iNO (n35)
• CMV alone (n38)
• Dobyns CCM 200230(11)2425

44
Conclusions

• P/F ratio greatest in the HFOV plus iNO group at
  4 and 12
  hours
• After 24 hours, both the HFOV plus iNO and HFOV
  alone resulted in greater
  P/F ratio improvement
• Speculation that enhanced lung recruitment by
  HFOV enhances the effects of iNO on gas
  exchange

45
Adjunctive Therapies - Proning

• Case report
• 56 yo man d/w drug overdose and aspiration
  failing CMV and iNO
• transitioned to HFOV plus iNO with improved
  ventilation
• proning (q 6-8h) initiated due to worsening
  oxygenation
• transitioned to CMV post 4 days, iNO weaned after
  9 days
• patient subsequently weaned and discharged
• Anesthesiology 200195(3)797

46
Unresolved Issues

• What is the best way to set Paw
• What are the best recruitment strategies
• How are hemodynamic parameters best assessed
• How are aerosols best delivered
• How to best predict responders
• Does HFOV result in less VILI than a conventional
  lung protective strategy

47
Take Home Messages

• Ventilation Strategies do affect patient outcomes
• Volume and pressure swings promote lung injury
  and mediator
  release.
• Identify patients at risk for developing VILI
  early- before the
  fibroproliferative stage
• Alternative therapies such as HFOV may offer
  lung
  protection that may improve outcomes for patients
  with ARDS