Did APRV kill the OSCILLATEr Star? -...
Transcript of Did APRV kill the OSCILLATEr Star? -...
![Page 1: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/1.jpg)
Did APRV kill the OSCILLATErStar?
John Davies MA RRT FAARC FCCPDuke Health System
Durham, North Carolina, USA
![Page 2: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/2.jpg)
HFOV – Theoretical advantages
Atelectrauma Volutrauma
HFOV
![Page 3: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/3.jpg)
![Page 4: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/4.jpg)
HFOV – Oscar Trial
• Young, et al. NEJM 2013;368:806.
• 398 patients in 29 centers in Great Britain
• HFOV vs. local physician practice
• No difference in mortality
• 3 centers had experience with HFOV, 6 centers “limited” experience and 20 centers no previous experience with HFOV
![Page 5: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/5.jpg)
HFOV – Oscillate Trial
Ferguson, et al. NEJM 2013
• 548 pts, 39 centers, 5 countries
• HFOV vs. Low Vt, high PEEP strategy in ARDS
• In hospital mortality in the HFOV group was 47% vs. 35% in the control group
• Concerns:
• Used higher mean airway pressures
• 2/3 pts were on pressors
• Many centers had little or no experience with the oscillator
• 75 pts were not enrolled because investigators felt HFOV would be of benefit
![Page 6: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/6.jpg)
HFOV – Meta analysis
Meade, et al. AJRCCM 2017;196:727.
• Meta-analysis of 4 large studies
• Looked at the different subgroups of ARDS
• Concluded that:
• “HFOV increases mortality for most patients with ARDS but may improve survival among patients with severe hypoxemia on conventional mechanical ventilation”
![Page 7: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/7.jpg)
APRV
Airway pressure release ventilation (APRV) was first described and introduced to clinical practice over 20 years ago. It became commercially available in the mid-1990s
• It is a mode of mechanical ventilation that is based on the open lung concept
• Inverse ratio ventilation
• Phigh, Plow, Thigh, Tlow
![Page 8: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/8.jpg)
APRV
• Long periods of inspiratory stretch (CPAP)
• More time for recruitment
• Oxygenation
• Release periods (exhalation)
• CO2 elimination
• Use autoPEEP to maintain recruitment
Long inspiratory stretch period
Rapid flow reversals
Added end -inspiratory volume
![Page 9: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/9.jpg)
APRV – Theoretical advantages
• Most of the evidence comes from animal studies
• Cannot necessarily extrapolate these results to humans
• Kacmarek, et al. AJRCCM 2006; 173:882
![Page 10: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/10.jpg)
APRV – Theoretical advantages
• Improved oxygenation
• Long I times
• Lung protective
• Improved comfort
• Spontaneous breathing encouraged• Fewer releases than conventional ventilation
• Outcomes
• Is it effective as a rescue therapy?
![Page 11: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/11.jpg)
APRV – Improved oxygenation
• The main causes of hypoxemia in ARDS are shunting due to alveolar collapse and reduction in functional residual capacity
• A prolonged inspiratory time is presumed to increase alveolar recruitment because it allows time for slow lung units a non-homogenous lung fields to inflate
![Page 12: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/12.jpg)
APRV
![Page 13: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/13.jpg)
APRV – Cautions
• Tidal overinflation
• Driving pressure
• Using oxygenation as a surrogate endpoint
• Potential for unsafe Vt’s
• Increased comfort???
• Potential for unsafe transpulmonarypressure
• Meaningful outcomes?
![Page 14: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/14.jpg)
APRV – Tidal overinflation
• AutoPEEP is established
mainly in lung units with long
expiratory time constants
• Ranieri, et al. JAMA 1999;
282:54
• Long expiratory time constants
result from:
– Increased compliance
– Increased airway resistance
• In ARDS the lung units in
which peep is needed are the
ones with the shortest exp time
constants
![Page 15: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/15.jpg)
APRV – Driving pressure
Amato MB et al. N Engl J Med 2015;372:747-755.
![Page 16: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/16.jpg)
APRV – Oxygenation as a surrogate endpoint
• Many will cite an improvement in oxygenation as a positive outcome
• However, consider the ARDSnet 6 vs 12 ml/kg IBW
NEJM 2000;342:1301
![Page 17: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/17.jpg)
APRV – Potential for unsafe Vt’s
• Hirshberg, et al. CCM 2018;46:1946
• Randomized Feasibility Trial - 52 pts, 4 centers:
• Low Vt - APRV Protocol
• Traditional APRV
• Volume Control Ventilation Protocols
• The study was stopped early because of low enrollment and inability to consistently achieve Vt’s < 6.5 mL/kg in the low Vt – APRV arm
![Page 18: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/18.jpg)
APRV –Potential for unsafe Vt’s
• Conclusion:
• APRV resulted in release volumes often exceeding 12 mL/kg despite a protocol designed to target low tidal volume ventilation
• Current airway pressure release ventilation protocols are unable to achieve consistent and reproducible delivery of low tidal volume ventilation goals
![Page 19: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/19.jpg)
APRV – Increased comfort?
• Maxwell, et al. J Trauma 2010;69:501
• 163 pts APRV vs LOVT (6 ml/kg PBW)
• APRV resulted in:
• Increased sedation use
![Page 20: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/20.jpg)
APRV – Potential for unsafe transpulmonarypressure
Transpul Press35
high 25
Spont effort:- -10
![Page 21: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/21.jpg)
APRV – Outcomes
• Maxwell, et al. J Trauma 2010;69:501
• 63 pts APRV vs LOVT ( SIMV, 6 ml/kg PBW)
• APRV resulted in:
• Increase in vent days, ICU LOS and VAP
![Page 22: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/22.jpg)
APRV – Outcomes
• Zhou, et al. Intensive Care Med 2017; 43:1648
• 138 pts APRV vs LTV
• APRV group had more ventilator-free days
• “In the APRV group, respiratory therapists would titrate APRV settings and dosages of analgesics and sedatives to achieve the target level of spontaneous breathing level”
![Page 23: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/23.jpg)
APRV - Summary
Oxygenation
• Long I times may help with recruitment
• Potential for large Vts and high driving pressures
• Not an endpoint
Comfort
• Spontaneous breathing may have some benefits hemodynamically but may produce harmful increases in transpulmonary pressure
• Conflicting evidence
Outcomes
• None demonstrated as better to date
![Page 24: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/24.jpg)
APRV – Survey
• Miller, et al. Respir Care 2017;62:1264
• Survey of the use of APRV
• 60 centers responded
• Take away message from this survey is that there is limited consensus on how to use APRV
• Some of the responses also indicated that practitioners may not appreciate the potential for VILI with APRV
![Page 25: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/25.jpg)
APRV
• Considering the fact that APRV has been around since 1986 and the fact that there are NO meaningful outcome studies that show a benefit it would seem that there are no advantages to using this mode
![Page 26: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/26.jpg)
Prone Ventilation - Proseva Study
• Guerin, et alI. NEJM 2013;368:2159
• Multicenter, prospective, randomized, controlled trial, 466 patients with severe ARDS:
• Prone-positioning of 16 hours vs
• Supine position
• 28 day mortality:
• Prone – 16%
• Supine – 33%
![Page 27: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/27.jpg)
ECMO – CESAR Trial
• Peek, et al. Lancet 2009;374:1351
• UK-based multicenter trial 180 adults:
• Conventional management
• Referral to consideration for treatment by ECMO
• In the ECMO group only 68/90 (75%) pts actually required ECMO
ECMO group - 63% six month survivalConventional - 47% six month survival (p = 0.03)
![Page 28: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/28.jpg)
ECMO - Growth
![Page 29: Did APRV kill the OSCILLATEr Star? - vtasymposium.co.zavtasymposium.co.za/wp-content/uploads/2020/03/2-14... · Did APRV kill the OSCILLATEr Star? John Davies MA RRT FAARC FCCP Duke](https://reader034.fdocuments.in/reader034/viewer/2022050206/5f590b7d19b9436ab13e8193/html5/thumbnails/29.jpg)
Conclusion
• APRV did not kill the OSCILLATE Star
• It was more the technological advances of ECMO, ECMO availability and the positive mortality benefit of prone ventilation
• OSCILLATE trial did teach us that, in many cases, we were using HFOV on the wrong patients